CN1720769A

CN1720769A - Parts mounting device and method

Info

Publication number: CN1720769A
Application number: CN 200380104731
Authority: CN
Inventors: 奥田修; 城户一夫; 内田英树; 岩本羽生; 矢泽隆; 吉富和之
Original assignee: Matsushita Electric Industrial Co Ltd
Current assignee: Panasonic Holdings Corp
Priority date: 2002-12-02
Filing date: 2003-12-02
Publication date: 2006-01-11
Anticipated expiration: 2023-12-02
Also published as: JP2004186308A; CN100407888C

Abstract

The invention relates to a component mounting device and a method, comprising an X-Y robot (120) constructed so as to linearly change its shape along the directions of X- and Y-axis, a camera reference mark (160), and a controller (170). Since the X-Y robot linearly changes its shape only along the directions of X- and Y-axis without producing displacement such as curving even if acted on by heat due to continuous operation, electronic parts can be mounted at a determined or substantially determined position by photographing the camera reference mark by a substrate recognition camera (140) to find the amount of thermal extension or contraction of the X-Y robot, and correcting the parts mounted position on the basis of the amount of extension or contraction.

Description

Component mounting apparatus and method

Technical Field

The present invention relates to a component mounting method and apparatus for mounting a component on a substrate with high accuracy. More particularly, the present invention relates to a component mounting apparatus and a component mounting method performed by the component mounting apparatus, and more particularly, to a component mounting apparatus and method considering thermal expansion and contraction of an X-Y robot that moves in an axis direction of X, Y and performs component mounting.

Background

Since the accuracy of mounting electronic components on an electronic circuit board is further minimized, high accuracy has been demanded in recent years. To achieve this mounting accuracy, various solutions have previously been proposed. For example, a method is disclosed in which a substrate mark present on a circuit board carried into a component mounting apparatus is imaged by a substrate recognition camera, the misalignment of the circuit board is determined, an electronic component held on a nozzle of an X-Y robot which moves in an X, Y axis direction and performs component mounting is imaged by a component recognition camera, the misalignment of the electronic component is determined, and the electronic component is mounted on the circuit board by the X-Y robot by correcting the two misalignments of the substrate and the component. In addition to this method, there is also proposed a method of obtaining relative positions of the suction nozzle of the X-Y robot, the substrate recognition camera, and the component recognition camera to further improve mounting accuracy (see, for example, japanese unexamined patent application publication No. 8-242094).

There is also proposed a method of further improving the mounting accuracy in consideration of the amount of expansion and contraction of the X-Y robot due to a temperature change of the component mounting apparatus accompanying the operation of the component mounting apparatus having the X-Y robot. In this method, as shown in fig. 28, a reference mark 4 is photographed by a substrate recognition camera 3 provided on a head 2 of an X-Y robot 1, and a displacement of the X-Y robot 1 due to heat is determined based on the photographed information (see, for example, japanese unexamined patent application publication No. 6-126671).

As described above, various methods have been proposed for improving the component mounting accuracy, but the progress in minimization of the electronic component is remarkable, and the component mounting accuracy is becoming stricter. Therefore, the above method may not satisfy the mounting accuracy for the electronic components in recent years. Specifically, currently, chip components of, for example, 1.6 × 0.8mm are required to be mounted with an error range of, for example, ± 70 μm.

In addition, in order to improve the component mounting accuracy, it is necessary to determine the relative positional relationship between the suction nozzle of the X-Y robot and the component recognition camera, but as described above, it is not easy to determine the relative positional relationship because the X-Y robot expands and contracts due to heat. That is, in consideration of the amount of expansion and contraction of the X-Y robot 1 due to heat, as shown in fig. 28, the X-Y robot 1 and the X-Y robot 7 constituting the X-Y robot 1 are disposed in orthogonal relation to each other, and even when heat is applied, the X-Y robot 1 expands and contracts while maintaining the orthogonal state, and can cope with the expansion and contraction. That is, if the respective expansion and contraction of the X-axis robot 7 and the Y-axis robot 8 occur only in one direction, the expansion and contraction amounts are the same or substantially the same at the position where the reference mark 4 is imaged by the camera 3 provided in the head 2 to obtain the expansion and contraction amount of the X-Y robot 1 and at the position where the head 2 actually mounts the electronic component on the printed circuit board 6, or the displacement amount of the mounting position can be calculated from the expansion and contraction amount of the reference mark imaging position, and the expansion and contraction amount obtained by the imaging can be used as the actual expansion and contraction amount.

However, conventionally, even when the mounting position correction is performed in consideration of the above-described amount of expansion and contraction, it is not possible to improve the mounting accuracy to a desired degree. The reason for this is not completely clear, but in the conventional configuration, it is considered that the reason is that when heat acts, expansion and contraction of the X-Y robot 1 occur not only in the X-axis direction and the Y-axis direction but also in other directions. That is, as illustrated in fig. 29 and 30 by way of example or exaggeratedly, it is considered that the X-axis robot 7 and the Y-axis robot 8 are deformed by heat, such as expansion and contraction and bending, respectively. Therefore, in the case where the camera 3 provided in the head 2 captures the image of the reference mark 4 in order to obtain the above-described amount of expansion and contraction of the X-Y robot 1 and the case where the head 2 actually mounts the electronic component on the printed board 6, the amount of expansion and contraction obtained does not contribute to correction of the mounting position regardless of the amount of expansion and contraction of the X-Y robot 1 and the direction of displacement, and therefore, it is considered that the mounting accuracy cannot be improved.

By driving the XY robot, the component suction head is moved in the XY direction, and recognition of the suction nozzle of the head sucking the component and the camera sucking the component, mounting of the component on the substrate, and the like are performed. The distortion of the component mounting apparatus itself causes poor machining accuracy or poor assembly accuracy of the XY robot of the component mounting apparatus.

When the components cannot be mounted with high accuracy when mounted on the substrate due to the distortion of the XY robot due to such machining accuracy or the like, the displacement in the XY direction occurs due to the yaw (yaw in the direction orthogonal to the advancing direction of the head moving on the XY robot), pitch (linear deterioration in the head moving path), roll (pitch in the direction 90 degrees different from the yaw) or the like of the guide members of the XY robot.

Therefore, conventionally, component mounting has been performed with high accuracy by observing a reference mark of a reference substrate with a substrate recognition camera fixed to an XY robot while performing camera calibration, calculating a displacement amount between a target position where the reference mark is originally to be located and an actual position of the reference mark, adding the calculated displacement amount to each position as a mounting position offset value, and performing correction (see, for example, japanese unexamined patent publication No. 6-126671).

Here, the camera calibration of the substrate recognition camera means that, in order to detect the assembly error of the substrate recognition camera, the jig whose position coordinates are known in advance is recognized by the substrate recognition camera, and the assembly error of the substrate recognition camera is calculated based on the difference between the position coordinates calculated based on the recognition result and the position coordinates known in advance, and the position correction is performed. In addition, when the above-described camera calibration is performed, not only the position correction of the substrate recognition camera but also the position correction of the component recognition camera and the suction nozzle are performed at the same time.

However, in the above-described method of correcting the respective positions, for example, in the 1 st positioning and the subsequent 2 nd positioning of the reference substrate, there may be a positional displacement of the reference substrate of approximately 1mm, and since very high accuracy is required, the price of the reference substrate is very high, and from the viewpoint of preventing damage, since the reference substrate is stopped and positioned at most X-direction positions without using a substrate stopper, and there is a gap of less than 1mm in the Y-direction for conveyance in the substrate conveyor, there is no reproducibility in positioning the reference substrate in the substrate holding portion in the component mounting apparatus, and the mounting accuracy is lowered.

In this way, after the reference substrate is positioned at a plurality of positions, the reference mark of the reference substrate is recognized to determine the relative displacement between the positions of the robot, and when the robot is mounted, the displacement is reflected in the position data of the mounting substrate, thereby reducing the mounting accuracy.

On the other hand, in the case of a method of identifying and correcting a glass reference substrate in which a grid is arranged in a matrix, it is considered that the grid of the reference substrate is measured on the premise that the reference substrate is accurately positioned, and the measured data is used as a correction value as it is.

However, as described above, it is difficult to accurately hold the reference substrate on the substrate holding portion in the micrometer unit, and a specific positioning device for accurately holding the reference substrate on the substrate holding portion of the component mounting apparatus is necessary, so that when measured data is directly used as a correction value, the XY robot cannot be accurately corrected unless the reference substrate is accurately positioned with good reproducibility.

However, when the mounting accuracy is not ensured, there is a problem that the mounting accuracy cannot be ensured because the head movement deformation due to the skew of the XY robot varies with the change of the positioning position and cannot be sufficiently corrected only by the conventional camera calibration and mounting position offset value when considered in the entire component mounting area of the component mounting device.

Even when a reference substrate itself in which a plurality of reference marks are arranged in a grid at equal intervals is precisely manufactured, absolute parallelism between the XY robot and the reference substrate cannot be achieved, and absolute perpendicularity cannot be ensured by the XY robot itself, so that there is no reference, and the XY robot supporting a head of a substrate recognition camera that recognizes the reference substrate arranged in a component mounting region of a component mounting device is tilted, and therefore, a position obtained from the reference substrate cannot be used as a reference, and mounting accuracy cannot be improved (for example, robot accuracy is improved to about ± 2 micrometers, and overall accuracy as a mounter is improved to about ± 20 micrometers).

Disclosure of Invention

The present invention has been made to solve the above-described problems, and an object thereof is to provide a component mounting apparatus and a component mounting method performed by the component mounting apparatus, which further improve component mounting accuracy than before.

Another object of the present invention is to provide a component mounting method and apparatus that can solve the above-described problems and improve mounting accuracy by obtaining an optimum offset value corresponding to the size of a substrate.

In order to achieve the above object, the present invention is configured as follows.

That is, according to the first aspect of the present invention, there is provided a component mounting apparatus provided with an X-Y robot having a component holding member for holding an electronic component, the electronic component held by moving in X-axis direction and Y-axis direction orthogonal to each other is mounted on a component mounting position of a circuit board; a fixed substrate recognition camera, which is arranged on the X-Y robot and shoots the substrate mark of the circuit substrate; and a component recognition camera for photographing the electronic component held on the component holding member, wherein

A camera reference mark arranged close to the component recognition camera; and

and a control device for correcting the component mounting position based on the position information of the camera reference mark obtained by the substrate recognition camera shooting the camera reference mark.

According to the 2 nd aspect of the present invention, there is provided the component mounting apparatus described in the 1 st aspect, further comprising a stage for component mounting apparatus configured in an integral structure,

the X-Y robot includes two identical Y-axis robots arranged parallel to each other in the Y-axis direction, and one X-axis robot arranged in the X-axis direction orthogonal to the Y-axis robots, each of the Y-axis robots being directly formed on the component mounting apparatus stage, and having a Y-ball screw structure in which one end is a fixed end and the other end is a support end, and the X-Y robot is linearly thermally extended and contracted only in the Y-axis direction and is moved in the Y-axis direction, and the X-Y robot is linearly thermally extended and contracted in the X-axis direction and the Y-axis direction.

According to a 3 rd aspect of the present invention, there is provided the component mounting apparatus according to the 2 nd aspect, wherein the X-axis robot has an X-frame, and both ends thereof are fixed to the ball screw structures provided in the respective Y-axis robots; and an X-ball screw structure formed in the X-frame, having one end as a fixed end and the other end as a support end, and linearly thermally expanding and contracting only in the X-axis direction, and assembling a component mounting head equipped with the component holding member so as to move the component mounting head in the X-axis direction, wherein the X-Y robot having the X-axis robot linearly thermally expands and contracts in the X-axis direction and the Y-axis direction.

According to the 4 th aspect of the present invention, there is provided the component mounting apparatus according to the 3 rd aspect, wherein the X-frame has a support guide member, is attached to the X-frame in the X-axis direction, slidably supports the component mounting head in the X-axis direction, and is made of a different material from the X-frame; and a deformation preventing member which is fitted to the X-frame in the X-axis direction with respect to the support guide member while holding the X-frame therebetween, and which prevents deformation of the X-frame, and is made of the same material as the support guide member.

According to a 5 th aspect of the present invention, there is provided the component mounting apparatus according to the 4 th aspect, wherein the component mounting head includes a plurality of the component holding members, and a drive source for holding the component for moving the component holding member in a Z-axis direction orthogonal to the X-axis direction and the Y-axis direction is independently provided for each of the component holding members, so that heat generation of the drive source for holding the component is reduced.

According to the 6 th aspect of the present invention, there is provided the component mounting apparatus as defined in any one of the 1 st to 5 th aspects, wherein the camera reference mark is arranged at a height position in a Z-axis direction orthogonal to the X-axis direction and the Y-axis direction, the height position being the same as a height position of the circuit board when the board mark on the circuit board is picked up by the board recognition camera.

According to the 7 th aspect of the present invention, there is provided the component mounting apparatus according to any one of the 1 st to 6 th aspects, wherein a plurality of the component recognition cameras are provided, and the camera reference mark is also provided in proximity to each of the component recognition cameras.

According to an 8 th aspect of the present invention, there is provided the component mounting apparatus according to the 1 st aspect, wherein the X-Y robot linearly thermally contracts in the X-axis direction and the Y-axis direction while keeping a relative position between the component holding member and the substrate recognition camera in an immovable state.

According to the 9 th aspect of the present invention, there is provided the component mounting apparatus according to the 8 th aspect, further comprising a component mounting apparatus gantry (110) which is integrally formed by casting so as to cause the X-Y robot to generate the linear thermal expansion and contraction.

According to a 10 th aspect of the present invention, there is provided the component mounting apparatus as defined in the 9 th aspect, wherein the X-axis robot has an X-frame having both ends fixed to the ball screw structures provided in the respective Y-axis robots, the X-frame having a support guide member fitted to the X-frame in the X-axis direction; and a deformation preventing member which is fitted to the X-frame in the X-axis direction with respect to the support guide member while holding the X-frame therebetween, and prevents deformation of the X-frame caused by heat, wherein the X-axis robot immobilizes a relative position between the member holding member and the substrate recognition camera.

According to an 11 th aspect of the present invention, there is provided the component mounting apparatus according to the 10 th aspect, wherein the X-axis robot further includes an X-ball screw structure formed in the X-frame, having one end as a fixed end and the other end as a support end, linearly thermally expanding and contracting only in the X-axis direction, and a component mounting head provided with the component holding member is mounted so as to move the component mounting head in the X-axis direction, the component mounting head including a plurality of the component holding members, and a drive source for holding members for moving the component holding members in a Z-axis direction orthogonal to the X-axis direction and the Y-axis direction is provided independently for each of the component holding members, and the component mounting head sets a relative position between the component holding member and the substrate recognition camera to a stationary state.

Further, according to the 12 th aspect of the present invention, there is provided a component mounting method performed by a component mounting apparatus having a component holding member that holds an electronic component, which mounts the electronic component held by being moved in an X-axis direction and a Y-axis direction orthogonal to each other to a component mounting position on a circuit substrate, wherein,

a substrate recognition camera for photographing the substrate mark on the circuit substrate is used to photograph a camera reference mark which is arranged close to the component recognition camera for photographing the electronic component held on the component holding element,

comparing the position information of the camera reference mark obtained by the photographing with the preset reference position information to obtain a difference,

when the electronic component held in the component holding member is moved to the fixed component recognition camera and photographed, the difference is used for correcting the movement amount,

after the electronic component is imaged by the component recognition camera, the displacement amount of the circuit board obtained by imaging the board mark by the board recognition camera is corrected, and the electronic component is moved to the mounting position of the circuit board and mounted.

According to the 13 th aspect of the present invention, there is provided the component mounting method according to the 12 th aspect, wherein when the mounting production is interrupted, the imaging of the camera reference mark is performed before the mounting production is restarted.

According to a 14 th aspect of the present invention, there is provided the component mounting method according to the 12 th or 13 th aspect, wherein when the difference obtained by the photographing is equal to or larger than a set value, the operation of the component mounting apparatus is stopped.

According to the 15 th aspect of the present invention, there is provided the component mounting method according to any one of the 12 th to 14 th aspects, wherein a positional relationship between the component holding device and the board recognition camera, a positional relationship between the component holding device and the component recognition camera, and a positional relationship between the board recognition camera and the component recognition camera are measured in advance, and these measurement values are processed as a correction premise of the component mounting apparatus.

According to the 16 th aspect of the present invention, there is provided the component mounting method according to any one of the 12 th to 15 th aspects, wherein when a plurality of the component recognition cameras are provided and a plurality of camera reference marks are provided, when the difference obtained by imaging one of the plurality of camera reference marks is less than a set value, imaging of the other camera reference mark is omitted.

In order to achieve the above object, the present invention may be configured as follows.

A component mounting apparatus is provided with an X-Y robot having a component holding member for holding an electronic component, the electronic component held by movement in X-axis and Y-axis directions orthogonal to each other is mounted on a component mounting position of a circuit board; a substrate recognition camera which is arranged on the X-Y robot and shoots the substrate mark of the circuit substrate; and a component recognition camera that photographs the electronic component held on the component holding member, characterized in that:

the X-Y robot is configured such that the relative position between the component holding member and the substrate recognition camera is set to a stationary state and the component holding member is linearly heat-shrunk in the X-axis direction and the Y-axis direction,

providing a camera reference mark and a control device, wherein the camera reference mark is arranged close to the component recognition camera and used for determining the expansion and contraction of the X-Y robot caused by heat;

and a controller for obtaining an amount of thermal expansion and contraction of the X-Y robot based on a plurality of position information of the camera reference marks obtained by imaging the camera reference marks with the substrate recognition camera before and after the thermal expansion and contraction of the X-Y robot, and correcting the component mounting position based on the amount of thermal expansion and contraction.

The controller may be configured to correct the component mounting position based on the relative positions of the component holding element, the board recognition camera, and the component recognition camera, and the amount of expansion and contraction.

Further, a stage for a component mounting apparatus is provided, which is formed in an integral structure by casting to cause the X-Y robot to generate the linear thermal expansion and contraction,

the X-Y robot includes two Y-axis robots arranged parallel to each other in the Y-axis direction, and one X-axis robot arranged in the X-axis direction orthogonal to the Y-axis robots, each of the Y-axis robots being directly formed on the component mounting apparatus stage, and having a Y-ball screw structure in which one end is a fixed end and the other end is a support end, and the X-axis robot is linearly thermally extended and contracted only in the Y-axis direction and is moved in the Y-axis direction, and the X-Y robot is linearly thermally extended and contracted in the X-axis direction and the Y-axis direction.

Further, the X-axis robot may have an X-frame, and both ends of the X-axis robot may be fixed to the ball screw structures provided in the Y-axis robots; and an X-ball screw structure formed in the X-frame, having one end as a fixed end and the other end as a support end, and linearly thermally expanding and contracting only in the X-axis direction, and assembling a component mounting head equipped with the component holding member so as to move the component mounting head in the X-axis direction, wherein the X-Y robot having the X-axis robot linearly thermally expands and contracts in the X-axis direction and the Y-axis direction.

Further, the X-frame may be provided with a support guide member, which is attached to the X-frame in the X-axis direction and slidably supports the component mounting head in the X-axis direction; and a deformation preventing member (138) which is fitted to the X-frame in the X-axis direction with respect to the support guide member while holding the X-frame therebetween, and prevents the X-frame from being deformed by heat of the support guide member, wherein the X-axis robot having the X-frame immobilizes a relative position between the component holding member and the substrate recognition camera.

In addition, the component mounting head may include a plurality of the component holding members, and a drive source for holding the component holding members may be provided independently of each of the component holding members so as to move the component holding members in a Z-axis direction orthogonal to the X-axis direction and the Y-axis direction, and the component mounting head may be configured to set a relative position between the component holding member and the substrate recognition camera to a stationary state.

The camera reference mark may be arranged at the same height position in a Z-axis direction orthogonal to the X-axis direction and the Y-axis direction as the circuit board when the board recognition camera takes an image of the board mark on the circuit board.

Further, according to the 17 th aspect of the present invention, there is provided a component mounting method as set forth in claim 12 for mounting the electronic component on the component holding device held by the component holding head movable relative to the substrate holding device at the component mounting position of the component mounting circuit board held by the substrate holding device,

recognizing the position coordinates of the mounting area reference marks arranged at predetermined intervals of the reference substrate held by the substrate holding device in a state where the mounting area reference mark recognition reference substrate is held by the substrate holding device and positioned in the component mounting area, and obtaining the position coordinates of the recognized mounting area reference marks,

the difference between the NC coordinates and the position coordinates of the reference marks of the respective mounting areas is obtained as a correction value,

NC coordinates of position coordinates of at least two substrate reference position calculating marks of the component mounting circuit substrate are obtained,

extracting mounting area reference marks respectively close to the two substrate reference position calculating marks from the recognized mounting area reference marks,

coordinate-converting the position coordinates of the extracted mounting area reference marks so that the correction values of the extracted mounting area reference marks are zero or substantially zero, and obtaining offset values under the respective mounting area reference marks,

on the other hand, in a state where the component mounting circuit board is held by the board holding device in place of the mounting area reference mark recognition reference board and positioned in the component mounting area, the at least two board reference position calculation marks of the component mounting circuit board held by the board holding device are recognized, respectively, and position coordinates of the recognized two board reference position calculation marks are obtained, respectively,

correcting the NC coordinates of the two substrate reference position calculation marks based on the position coordinates of the two substrate reference position calculation marks,

when the component held by the component holding head is positioned above the component mounting device of the component mounting circuit board, the position coordinates of the component mounting position are corrected based on the offset value of the mounting area reference mark closest to the recognition camera provided in the component holding head, and then the component is mounted to the component mounting position based on the corrected position coordinates of the component mounting position.

Further, according to another aspect of the present invention, there is provided a component mounting method for mounting a component held by a component holding head movable relative to a substrate holding device at a component mounting position of a component mounting circuit board held by the substrate holding device, the component mounting method including:

According to the 18 th aspect of the present invention, there is provided the component mounting method as defined in the 17 th aspect, wherein the positional coordinates of the extracted mounting area reference marks are coordinate-converted so that the correction values of the extracted mounting area reference marks close to the two substrate reference position calculating marks are zero or substantially zero, and the offset values under the respective mounting area reference marks are obtained,

in this case, the extracted mounting area reference mark is rotated and moved in a curve connecting the extracted mounting area reference marks, and coordinate conversion is performed so that the correction value of the extracted mounting area reference mark close to each of the two substrate reference position calculation marks becomes zero or substantially zero, thereby coordinate-converting the position coordinates of the extracted mounting area reference mark and obtaining the offset value under each mounting area reference mark.

According to the 19 th aspect of the present invention, there is provided the component mounting method as defined in the 17 th or 18 th aspect, wherein the positional coordinates of the extracted mounting area reference marks are coordinate-converted so that the correction values of the extracted mounting area reference marks close to the two substrate reference position calculating marks are zero or substantially zero, and the offset values under the respective mounting area reference marks are obtained,

in this case, a correction value in at least one of an X direction of the substrate holder and a Y direction orthogonal to the X direction is calculated based on the extracted mounting area reference mark, a tilt of the reference substrate is calculated, position coordinates of the extracted mounting area reference mark are coordinate-converted so that the correction value of the extracted mounting area reference mark becomes zero or substantially zero, and an offset value under each mounting area reference mark is calculated.

According to the 20 th aspect of the present invention, there is provided a component mounting apparatus as set forth in claim 1, wherein the electronic component is mounted on the component holding member held by the component holding head movable by the X-Y robot relative to the substrate holding apparatus at the component mounting position of the component mounting circuit board held by the substrate holding apparatus,

the substrate recognition camera is provided in the component holding head supported by the X-Y robot, and recognizes position coordinates of mounting area reference marks arranged at predetermined intervals of the reference substrate held by the substrate holding device in a state where the reference substrate for mounting area reference mark recognition is held by the substrate holding device and positioned in a component mounting area,

on the other hand, the electronic component mounting apparatus further comprises a calculation unit for calculating position coordinates of the mounting area reference marks based on a recognition result of the mounting area reference marks recognized by the board recognition camera, and for calculating differences between the NC coordinates of the mounting area reference marks and the position coordinates, respectively, as correction values, extracting mounting area reference marks respectively adjacent to the two board reference position calculation marks from the recognized mounting area reference marks based on the NC coordinates of the position coordinates of the at least two board reference position calculation marks of the electronic component mounting circuit board, respectively, for coordinate-converting the position coordinates of the extracted mounting area reference marks so that the correction values of the extracted mounting area reference marks are zero or substantially zero, and for calculating offset values under the mounting area reference marks, in a state where the component-mounting circuit board is held by the board holding device in place of the mounting-area reference mark recognition reference board and positioned in the component mounting area, the at least two board reference position calculation marks of the component-mounting circuit board held by the board holding device are recognized, respectively, position coordinates of the recognized two board reference position calculation marks are obtained, respectively, and the NC coordinates of the two board reference position calculation marks are corrected, respectively, based on the obtained position coordinates of the two board reference position calculation marks,

the control device performs correction of the position coordinates of the component mounting position based on an offset value of the mounting area reference mark closest to the recognition camera provided in the component holding head while the component held in the component holding head is positioned above the component mounting device of the component mounting circuit board, and then mounts the component to the component mounting position based on the corrected position coordinates of the component mounting position.

According to a 21 st aspect of the present invention, there is provided the component mounting apparatus as defined in the 20 th aspect, the computing section coordinate-converts the position coordinates of the extracted mounting area reference marks so that the correction values of the extracted mounting area reference marks close to the two substrate reference position calculating marks are zero or substantially zero, and calculates the offset values under the respective mounting area reference marks, performing coordinate transformation by rotating and moving a curve connecting the extracted mounting area reference marks, so that the correction values of the extracted mounting area reference marks close to the two substrate reference position calculation marks are zero or substantially zero, thus, the position coordinates of the extracted mounting area reference mark are respectively subjected to coordinate transformation, and the offset value under each mounting area reference mark is obtained.

According to the 22 nd aspect of the present invention, there is provided the component mounting apparatus as defined in the 20 th or 21 st aspect, the computing section coordinate-converts the position coordinates of the extracted mounting area reference marks so that the correction values of the extracted mounting area reference marks close to the two substrate reference position calculating marks are zero or substantially zero, and calculates the offset values under the respective mounting area reference marks, calculating a correction value in at least one direction of an X direction of the substrate holder and a Y direction orthogonal to the X direction based on the extracted mounting area reference mark, and calculating the inclination of the reference substrate, performing coordinate transformation on the position coordinates of the extracted mounting region reference marks to make the correction value zero or substantially zero, and calculating the offset value under each mounting region reference mark.

According to the 23 rd aspect of the present invention, there is provided the component mounting apparatus as defined in any one of the 20 th to 22 th aspects, comprising an XY robot having two Y-axis robots disposed parallel to each other in a Y-axis direction and one X-axis robot, wherein the component holding head is movably supported in the X-axis direction while being movably disposed in the two Y-axis robots in an X-axis direction orthogonal to the Y-axis direction, and wherein the component holding head is movable in the XY-axis direction with respect to the substrate holding device by the two Y-axis robots and the one X-axis robot.

According to a 24 th aspect of the present invention, there is provided the component mounting apparatus according to the 23 th aspect, wherein the component holding head has a plurality of component suction nozzles which can suction and hold the components, respectively, and are arranged in the X-axis direction, and the board recognition camera is disposed on the component holding head such that an imaging center of the board recognition camera is positioned on the same axis as a straight line passing through centers of the plurality of component suction nozzles.

Drawings

These and other objects and features of the present invention will become apparent from the following description of the best mode contemplated for carrying out the invention in connection with the accompanying drawings. Wherein,

fig. 1 is a plan view of a component mounting apparatus as a 1 st embodiment of the present invention,

figure 2 is a front view of the component mounting apparatus shown in figure 1,

figure 3 is a right side view of the component mounting apparatus shown in figure 1,

figure 4 is a schematic diagram of a gantry and X-Y robot provided in the component mounting apparatus shown in figure 1,

FIG. 5 is a view showing a fixed end of a ball screw structure of the X-Y robot provided in the component mounting apparatus shown in FIG. 1,

FIG. 6 is a view showing a support end of a ball screw structure of an X-Y robot provided in the component mounting apparatus shown in FIG. 1,

fig. 7 is a view showing an X-frame portion of an X-axis robot provided in the component mounting apparatus shown in fig. 1,

fig. 8 is a front view of a component mounting head of an X-axis robot provided in the component mounting device shown in fig. 1,

fig. 9 is a front view of a component recognition camera and a camera reference mark part provided in the component mounting apparatus shown in fig. 1,

figure 10 is a plan view of the part recognition camera and camera fiducial mark portion of figure 9,

FIG. 11 is a block diagram showing the relationship between each constituent part of the component mounting apparatus shown in FIG. 1 and a control apparatus,

fig. 12 is a flowchart for explaining a component mounting method performed by the component mounting apparatus shown in fig. 1,

fig. 13 is a graph showing the relationship between the passage of time and the temperature of each part of the component mounting head provided in the component mounting device shown in fig. 1,

fig. 14 is a graph comparing the component mounting device shown in fig. 1 with a conventional component mounting device with respect to the misalignment of each component nozzle provided in the component mounting head with the passage of the running time,

FIG. 15 is a graph showing the amount of deformation of the X-axis robot of the component mounting apparatus shown in FIG. 1 due to a change in temperature,

FIG. 16 is a graph showing the amount of deformation of an X-axis robot in a conventional component mounting apparatus due to a change in temperature,

FIG. 17 is a graph showing the amount of positional displacement at each measurement point with the passage of operating time in the component mounting apparatus shown in FIG. 1,

FIG. 18 is a graph showing the amount of displacement at each of the measurement points shown in FIG. 17,

FIG. 19 is a view showing the measurement points shown in FIGS. 17, 18, 20 and 21,

FIG. 20 is a graph showing the amount of positional displacement at each measurement point with the passage of operating time in the conventional component mounting apparatus,

FIG. 21 is a graph showing the amount of displacement at each of the measurement points shown in FIG. 20,

FIG. 22 is a graph showing the displacement of the camera reference mark and the mounting position accuracy in the Y-axis direction according to the change in the atmospheric temperature and the variation in the mounting position accuracy in the component mounting apparatus shown in FIG. 1,

FIG. 23 is a graph showing the displacement of the camera reference mark and the mounting position accuracy in the X-axis direction according to the change in the atmospheric temperature and the variation in the mounting position accuracy in the component mounting apparatus shown in FIG. 1,

FIG. 24 is a plan view of a modification of the component mounting apparatus shown in FIG. 1,

FIG. 25 is a view showing a difference in mounting position from a predetermined position when component mounting is performed by the component mounting apparatus shown in FIG. 1,

FIG. 26 is a view showing a difference in mounting position from a predetermined position when component mounting is performed by a conventional component mounting apparatus,

FIG. 27 is a view showing a difference in mounting position from a predetermined position when component mounting is performed by a conventional component mounting apparatus,

figure 28 is an oblique view showing a conventional component mounting apparatus,

FIG. 29 is a view schematically showing a deformation of an X-Y robot due to the influence of heat in a conventional component mounting apparatus,

FIG. 30 is a view schematically showing a deformation of an X-Y robot due to the influence of heat in a conventional component mounting apparatus,

FIG. 31 is a plan view of a component mounting apparatus in which the component mounting method according to embodiment 2 of the present invention can be implemented,

figure 32 is a front view of the above-described component mounting apparatus shown in figure 31,

figure 33 is a right side view of the above-described component mounting apparatus shown in figure 31,

fig. 34 is a schematic view of a stage and an XY robot provided in the above-described component mounting apparatus shown in fig. 31,

fig. 35 is a front view of the component mounting head of the X-axis robot provided in the above-described component mounting apparatus shown in fig. 31,

FIG. 36 is a block diagram showing the relationship between each component of the above-described component mounting apparatus shown in FIG. 31 and a control apparatus,

FIG. 37 is an explanatory view showing a relationship between the distortion of the X-axis robot and the component mounting head for explaining the positional accuracy of the component mounting head which is greatly affected by the distortion of the XY robot,

FIG. 38 is an explanatory view showing a relationship between the distortion of the Y-axis robot and the component mounting head for explaining the positional accuracy of the component mounting head which is greatly affected by the distortion of the XY robot,

FIG. 39 is an explanatory view for explaining the offset value idea of the component mounting method according to embodiment 2 of the present invention,

FIG. 40 is a plan view showing a specific example of a glass substrate used in the component mounting method according to embodiment 2 of the present invention,

FIG. 41 is a flowchart showing steps for determining an offset value of the component mounting method according to embodiment 2 of the present invention,

FIG. 42 is a plan view showing a reference mark of a mounting region of a glass substrate used in the component mounting method according to embodiment 2 of the present invention,

FIG. 43 is an explanatory view for explaining a method of recognizing a reference mark in a mounting region of a glass substrate used in the component mounting method according to embodiment 2 of the present invention,

fig. 44 shows the component mounting method according to embodiment 2 of the present invention, in which the position is shifted from the center O of the field of view of the board recognition camera₁、O₂To identify the location of the fiducial marks of the mounting area,

FIG. 45 is an explanatory view showing a result of recognizing two reference position calculation marks for the substrate in the component mounting method according to embodiment 2 of the present invention,

FIG. 46 is a graph in which the vertical axis represents the amount of displacement, the horizontal axis represents the position in the X direction, the upper broken line graph represents Δ X, i.e., the displacement in the X direction, and the lower broken line graph represents Δ Y, i.e., the displacement in the Y direction,

FIG. 47 is an explanatory view showing a state where the reference mark position of the mounting region is displaced in the X direction and the Y direction from the center position of the rectangular field of view region as the original position,

FIG. 48 is a view showing a state in which the mounting positions are rearranged after the mounting area reference mark correction values near the two substrate reference position calculating marks of the relatively small-sized substrate to be mounted are zero or substantially zero by performing coordinate conversion by rotating and moving the curve,

FIG. 49 is a plan view showing two reference position calculating marks for the substrate to be mounted on the smaller substrate in FIG. 48,

FIG. 50 is a view showing a state where the mounting position is rearranged after the mounting area reference mark correction value in the vicinity of two substrate reference position calculation marks of a large-sized substrate to be mounted is zero or substantially zero by performing coordinate conversion by rotating and moving the curve,

FIG. 51 is a plan view showing two reference position calculating marks for the substrate to be mounted on the larger substrate in FIG. 50,

FIG. 52 is an explanatory view showing a reference mark of a mounting region on a glass substrate closest to a reference position calculating mark of a production substrate,

FIG. 53 is an explanatory view showing a state in which a region P surrounded by 4 dot mounting region reference marks is divided into one region when M rows of mounting region reference marks are arranged in the longitudinal direction of a substrate to be mounted and N columns of mounting region reference marks are arranged in the transverse direction,

fig. 54 is a flowchart of an operation of recognizing a reference mark of a mounting area in a more specific example of the component mounting method according to embodiment 2,

FIG. 55 is a flowchart of a variety selecting operation in a more specific example of the component mounting method according to embodiment 2,

fig. 56 is a flowchart of the mounting region reference mark recognition operation and the component mounting operation of a more specific example of the component mounting method according to embodiment 2 described above,

FIG. 57 is an explanatory view of a combination of positional coordinate data [1] of a mounting area reference mark measured at a normal position of a substrate and positional coordinate data [2] of a mounting area reference mark measured at a position shifted leftward by 350mm,

FIG. 58 is a graph showing the relationship between the X-direction position and the X-direction displacement amount of the substrate of FIG. 57 when the head is moved in the X-direction at a pitch of 10mm,

FIG. 59 is a graph showing the relationship between the Y-direction position and the Y-direction displacement amount of the substrate of FIG. 57 when the head is moved in the Y-direction at a pitch of 10mm,

FIG. 60 is a graph showing mounting accuracy when the offset value of embodiment 2 is not applied to a substrate having a size of 428mm × 250mm and a ceramic capacitor of a chip component having a size of 1.6mm × 0.8mm as 400 points is mounted on the substrate, and shows a mounting error amount in the Y direction on the vertical axis and a mounting error amount in the X direction on the horizontal axis,

FIG. 61 is a graph showing mounting accuracy when the offset value of embodiment 2 is applied to a substrate having a size of 428mm × 250mm and a ceramic capacitor of a chip component having a size of 1.6mm × 0.8mm as 400 points mounted on the substrate, and shows a mounting error amount in the Y direction on the vertical axis and a mounting error amount in the X direction on the horizontal axis,

FIG. 62 is a graph showing mounting accuracy when a plurality of QFPs are mounted on a substrate of 428mm × 250mm in size, but the offset values of embodiment 2 are not applied, and shows the amount of mounting misalignment in the Y direction on the vertical axis and the amount of mounting misalignment in the X direction on the horizontal axis,

FIG. 63 is a graph showing mounting accuracy when applying the offset values of embodiment 2 above to a substrate having a size of 428mm × 250mm when mounting a plurality of QFPs on the substrate, showing the amount of mounting misalignment in the Y direction on the vertical axis and the amount of mounting misalignment in the X direction on the horizontal axis,

FIG. 64 is an explanatory view showing the displacement amounts in the X direction and the Y direction from the center of the visual field of the substrate recognition camera to the reference mark of the mounting region,

FIG. 65 is a flowchart showing an operation in which an area offset value due to the motion deformation of the XY robot included in the inter-nozzle pitch and the substrate camera offset value is reflected on the inter-nozzle pitch and the substrate camera offset value as an application example of embodiment 2,

FIG. 66 is a flowchart showing a procedure of executing a component mounting operation by reflecting an area offset value on a measurement position of a pitch between suction nozzles,

FIGS. 67A, 67B, and 67C are views showing the positional relationship between the suction nozzle, the component recognition camera, and the substrate recognition camera during measurement,

fig. 68 is a diagram for explaining an offset value of the substrate camera and an inter-nozzle pitch.

Detailed Description

Hereinafter, a component mounting apparatus and a component mounting method performed by the component mounting apparatus, which are embodiments of the present invention, will be described in detail with reference to the accompanying drawings. In the drawings, the same components are denoted by the same reference numerals.

As shown in fig. 1 to 4, the component mounting apparatus 100 according to embodiment 1 includes, as basic components, a stage 110, an X-Y robot 120, a substrate recognition camera 140, a component recognition camera 150, a camera reference mark 160, a control device 170, a component supply device 180, and a substrate transport device 190.

The stage 110 is a base stage for installing the X-Y robot 120, the component recognition camera 150, the camera reference mark 160, the control device 170, the component supply device 180, and the substrate transfer device 190, and is composed of a base portion 111 having a rectangular parallelepiped shape and a Y-axis robot leg portion 112, and the base portion 111 and the Y-axis robot leg portion 112, that is, the stage 110, are molded in an integral structure by casting. The Y-axis robot leg portion 112 is provided along the X-axis direction 51 so as to protrude from the base portion 111 at both ends of the base portion 111, and extends along the Y-axis direction 52 orthogonal to the X-axis direction 51. A linear guide 123 and the like in a Y-axis robot 121 described later in detail constituting the X-Y robot 120 are provided in each Y-axis robot leg 112. The respective linear guides 123, which are guide support members of the nut portions 126 described below, are provided in the Y-axis robot leg portions 112 along the linear-guide provision surfaces 123a formed in the respective Y-axis robot leg portions 112 in the Y-axis direction 52, but since the respective Y-axis robot leg portions 112 and the base portion 111 are molded in an integral structure by casting as described above, the respective linear-guide provision surfaces 123a can be completed with very high accuracy by machining. Therefore, the parallelism between the two linear guide mounting surfaces 123a, that is, the parallelism between the two Y-axis robots 121 can be realized with an accuracy of about 0.02mm or less.

Further, the gantry constituting the conventional component mounting apparatus is manufactured by melting a section steel or the like, and a Y-axis robot different from the gantry manufactured is fixed to the gantry of the section steel by bolts. Therefore, it is difficult to improve the parallelism between the two Y-axis robots to such an extent that the component mounting accuracy is not affected, and the parallelism between the Y-axis robots in the conventional component mounting apparatus is considerably inferior to that of the Y-axis robot 121 of embodiment 1.

The X-Y robot 120 includes two Y-axis robots 121 provided in parallel with each other in the Y-axis direction 52 on the respective Y-axis robot legs 112, i.e., the gantry 110 formed in an integral structure by casting, and one X-axis robot 131 arranged in the X-axis direction 51 so as to be orthogonal to the Y-axis robot 121.

Each Y-axis robot 121 has the Y-ball screw structure 122 and the linear guide 123 described above. The Y-ball screw structure 122 is configured to extend and contract linearly only in the Y-axis direction 52 by heat while moving the X-axis robot 131 in the Y-axis direction 52, with one end 122a being a fixed end and the other end 122b being a support end. Specifically, as shown in fig. 5, a motor 124, which is fixed to the Y-axis robot leg 112 and serves as a drive source of a ball screw 125, is provided at the one end 122a of the Y-ball screw structure 122, and is coupled to the ball screw 125. As shown in fig. 6, the other end 122b is attached to the Y-axis robot leg 112 so as to be rotatable in the circumferential direction thereof and to support a ball screw 125 so as to be extendable and retractable in the axial direction, i.e., the Y-axis direction 52.

When the Y-axis robot 121 thus configured is continuously operated, the heat generating portions are the ball screw 125 and the motor 124, and the other end 122b allows the thermally induced expansion and contraction of the ball screw 125 in the Y-axis direction 52. Since the motor 124 is fixed to the stage 110 having an integral structure as described above, thermal expansion and contraction, which is expansion and contraction of the Y-axis robots 121 due to heat, is linear only in the Y-axis direction 52. Since the two Y-axis robots 121 operate in the same manner, the thermal expansion and contraction amounts of the respective Y-axis robots 121 in the Y-axis direction 52 are equal.

As shown in fig. 4, a nut portion 126 is attached to the ball screw 125 of each Y-axis robot 121, and the nut portion 126 is moved in the Y-axis direction 52 by the rotation of each ball screw 125. An X-axis robot 131 constituting the X-Y robot 120 is disposed between the nut portions 126 in the X-axis direction 51. As described above, since the Y-axis robots 121 expand and contract in the Y-axis direction 52 by the same amount, the X-axis robot 131 provided between the nut portions 126 can move in the Y-axis direction 52 in parallel with the X-axis.

Fig. 4 is a diagram schematically showing the structures of the stage 110 and the X-Y robot 120, and the structures of the component mounting apparatuses 100 shown in fig. 1 to 3 do not necessarily match each other, and the component mounting heads described later are not shown. In fig. 2 to 4, illustration of the component supply device 180 is omitted.

The X-axis robot 131 has an X-frame 132 and an X-ball screw configuration 133. As described above, the X-frame 132 has both ends fixed to the nut portions 126 of the ball screw structures 122 of the respective Y-axis robots 121 and extends in the X-axis direction 51. The X-ball screw structure 133 is formed in the X-frame 132, and has one end 133a as a fixed end and the other end 133b as a support end, and is configured to linearly expand and contract only in the X-axis direction 51 by heat, and the component mounting head 136 is assembled to move the component mounting head 136 in the X-axis direction 51.

The X-frame 132 is a member made of aluminum having a substantially square column shape shown in fig. 7, and both ends thereof are fixed to the nut portions 126 as described above. As shown in fig. 4, etc., a motor 135 as a driving source of a ball screw structure 134 fixed to the X-frame 132 is provided at the one end 133a of the X-ball screw structure 133 formed on the side surface of the X-frame 132, and is connected to the ball screw 134. As shown in fig. 6, the other end 133b is rotatably supported in the circumferential direction thereof and telescopically supports a ball screw 134 in the axial direction thereof, i.e., in the X-axis direction 51, and is attached to the X-frame 132. When the X-axis robot 131 is continuously operated, the heat generating portions are the ball screw 134 and the motor 135, and the other end 133b allows the thermally induced expansion and contraction of the ball screw 134 in the X-axis direction 51.

As shown in fig. 1, a nut 134a for mounting the component mounting head 136 is mounted on the ball screw 134, and the nut 134a, that is, the component mounting head 136 is moved in the X-axis direction 51 by the rotation of the ball screw 134.

The component mounting head 136 includes a component nozzle 1361 as an example of realizing a function of holding a component as a component holding element for holding the electronic component 62, and a board recognition camera 140 for capturing an image of a board mark 61a present on the circuit board 61 in order to confirm a displacement of the circuit board 61 loaded in the embodiment 1. As shown in fig. 8, the component suction nozzle 1361 includes 8 component suction nozzles 1361 arranged in a straight line in the X-axis direction 51 in embodiment 1. The electronic component 62 is a small component such as a chip component, a large component such as QFP, or the like. Thus, the component nozzle 1361 is also equipped with a nozzle of an optimal size and shape corresponding to various components to be sucked. As described above, the substrate recognition camera 140 is disposed such that the imaging center of the substrate recognition camera 140 is located on the same axis as a straight line passing through the centers of the respective nozzles 1361 arranged in the X-axis direction. Further, the component mounting head 136 is provided with a rotating motor 1363 for rotating the component nozzles 1361 in the axial direction thereof.

Since each component nozzle 1361 sucks the electronic component 62 from the component supply device 180 and mounts the sucked electronic component 62 on the circuit board 61, it is necessary to move in the axial direction of the component nozzle 1361, that is, the Z-axis direction 53. In embodiment 1, in the component mounting head 136, in order to move the component nozzle 1361, a moving motor 1362 serving as an example of a driving source for holding components is provided in the component nozzle 1361. Thus, compared with the conventional case where all of the plurality of component nozzles are driven by one large-output motor, a motor with a low output can be used, and the amount of heat generated from the motor can be suppressed. In one embodiment, the output of the moving motor 1362 is 20W, and heat is not substantially generated from the moving motor 1362. In addition, in the case where the large output motor having a large amount of heat generation is provided in the past, the conventional component mounting head generates a temperature gradient in accordance with the distance from the large output motor, and the distance between the suction nozzles of the respective components in the arrangement direction is different depending on the thermal expansion and contraction. In contrast, in embodiment 1, by providing the moving motor 1362 in each component nozzle 1361, heat generation from each moving motor 1362 is substantially absent, and even if heat generation is assumed, the component mounting head 136 does not generate a temperature gradient that affects the degree of component mounting accuracy. Thus, even if the component mounting head 136 is continuously run, the distances between the component nozzles 1361 in the X-axis direction 51 can be maintained in an equal or substantially equal state. The substantially equal state is a state that does not affect the component mounting accuracy.

In addition, as described above, since the component mounting head 136 does not generate a temperature gradient that affects the component mounting accuracy, the relative position of each component nozzle 1361 and the substrate recognition camera 140, that is, the distance between each component nozzle 1361 and the substrate recognition camera 140 can be set to be constant. Here, "stationary" means that the distance between each component nozzle 1361 and the board recognition camera 140 does not expand or contract due to heat to such an extent that the component mounting accuracy is not affected.

Fig. 13 shows the results of temperature measurement of each part of the component mounting head 136, which proves that no harmful temperature gradient is generated in the component mounting head 136. In fig. 13, the "1 st motor" is a motor arranged at the left end in the 8 moving motors 1362 shown in fig. 8, the "4 th motor" is a motor arranged at the 4 th position from the left end, and the "head frame" is a frame member forming the component mounting head 136. As can be seen from fig. 13, the temperature change of each part of the component mounting head 136 is suppressed within about 5 degrees regardless of the time elapsed from the start of the operation of the component mounting head 136. Thus, it is not considered that the component mounting head 136 has substantially no deformation affecting the component mounting accuracy as deformation caused by a temperature change.

Further, as described above, since the temperature change of the component mounting head 136 is smaller than before, it is known that the amount of the distance misalignment between the component nozzles 1361 positioned at the left and right ends of the component mounting head 136 is substantially constant regardless of the passage of time, and is within about 1 μm, as shown in fig. 14. In addition, the displacement within about 1 μm is not a displacement amount that affects the component mounting accuracy. On the other hand, since the conventional apparatus generates a large temperature gradient as described above, as shown in the figure, the amount of displacement of the distance between the nozzles increases with the passage of time (with the passage of a certain time).

As is clear from the measurement results in fig. 13 and 14, the distances between the respective component nozzles 1361 in the X-axis direction 51 can be maintained substantially equal to each other regardless of the elapsed operating time of the component mounting head 136, and the distances between the respective component nozzles 1361 and the board recognition camera 140 are not substantially expanded or contracted by heat.

Also, since the X-frame 132 is slidably supported in the X-axis direction 51 by the supporting member mounting head 136, as shown in fig. 2 and 7, a linear guide 137 made of iron of a different material from the X-frame 132 as two supporting guide members is fitted in parallel in the X-axis direction 51. Further, in the X-frame 132, a deformation preventing member 138 is fitted to hold the X-frame 132 and prevent the X-frame 132 from being deformed in the X-axis direction 51 with respect to the linear guides 137 in the X-frame 132, and the deformation preventing member 138 is made of iron of the same material as the linear guides 137.

Next, the reason why the structure of the X-frame 132, to which the linear guide 137 is fitted, and the deformation preventing member 138 are fitted by sandwiching is described. That is, as described above, when the X-axis robot 131 is continuously operated, the ball screw 134 and the motor 135 mainly generate heat, and the linear guides 137 also generate heat. This heat is also transferred to the X-frame 132. As shown in fig. 7, the X-frame 132 is superior in volume and the like as compared to the motor 135 and the linear guide 137, and is considered to be substantially free from thermally induced expansion and contraction and deformation in a manner that is as non-deformable as possible. However, since the X-frame 132 is made of aluminum and the linear guides 137 are made of iron as described above, it is considered that the X-frame 132 may be deformed such as bent due to the difference in thermal expansion coefficient between the two. Therefore, by fitting the above-described deformation preventing member 138 made of iron in exactly the same shape, size, and arrangement as the respective linear guides 137, the above-described deformation of the X-frame 132 can be cancelled out. Therefore, it is considered that the X-frame 132 does not expand and contract in the X-axis direction 51 due to heat and also does not deform such as bend, or the amount of expansion and deformation is a value to a negligible extent in terms of the component mounting operation.

With the above-described configuration of the X-axis robot 131, it can be seen that the only portion of the X-axis robot 131 that thermally expands and contracts is the ball screw 134, and the expansion and contraction direction thereof is linear only in the X-axis direction 51.

The effect of providing the deformation preventing member 138 will be described with reference to fig. 15 and 16. Fig. 15 shows the amount of deformation of the X-axis robot in the Y-axis direction 52 when the deformation preventing member is provided in the X-frame, and fig. 16 shows the amount of deformation when the deformation preventing member is not provided. Fig. 15 and 16 are graphs showing temperature changes of 20 ℃→ 40 ℃ → 20 ℃ applied to the X-axis robot, and the horizontal axis shows the distance from the reference point of the ball screw driving motor provided in the X-axis robot.

As is clear from the graphs in fig. 15 and 16, when the deformation preventing member is provided, the amount of deformation in the X-axis robot is suppressed to within ± 10 μm, and it is considered that substantially no deformation occurs. On the other hand, when the deformation preventing member is not provided, the deformation of 90 μm at the maximum is generated, and it is found that the component mounting accuracy is significantly affected.

As is clear from the experimental results, the X-axis robot 131 according to embodiment 1, in which the deformation preventing member 138 is attached to the X-frame 132, is considered to be not expanded and contracted in the X-axis direction 51 by heat and not deformed by bending or the like, or to have a value such that the amount of expansion and contraction is negligible in terms of the component mounting operation, as described above, and it is also known that the portion of the X-axis robot 131 expanded and contracted by heat is only the ball screw 134.

According to the structure of the gantry 110 and the X-Y robot 120 constituting the component mounting apparatus 100 according to embodiment 1 described above, even when heat is applied, the robot 121 constituting the X-Y robot 120 linearly thermally expands and contracts only in the Y-axis direction 52, and the ball screw 134 alone of the X-axis robot 131 linearly thermally expands and contracts only in the X-axis direction 51. Further, since the X-axis robot 131 is supported by the left and right Y-axis robots 121 and moves in the Y-axis direction 52, the amounts of heat generated by the Y-axis robots 121 are equal, and the amounts of thermal expansion and contraction of the Y-axis robots 121 in the Y-axis direction 51 are equal. Therefore, even when heat acts on the X-Y robot, the component mounting head 136 fitted to the ball screw 134 of the X-axis robot 131 is displaced only in the X-axis direction 51 and the Y-axis direction 52. Further, as described above, when heat is applied, expansion and contraction and deformation that hinder component mounting accuracy are not generated in the distance between the component nozzles 1361 in the component mounting head 136 and the distance between the component nozzles 1361 and the board recognition camera 140 provided in the component mounting head 136.

Therefore, even when heat acts on the X-Y robot 120, the X-Y robot 120 is not subjected to 3-dimensional displacement such as bending, which adversely affects component mounting accuracy, but is subjected to displacement only in the X-axis direction 51 and the Y-axis direction 52. This is also clear from the experimental data shown below.

That is, as shown in fig. 19, when 4 points, such as points a to D, arranged in the Y axis direction 52 of the circuit board 61 loaded into the component mounting apparatus and point E as the camera reference mark 160 are recognized by the board recognition camera mounted on the X axis robot of the X-Y robot, the change in the position of the points a to D in the Y axis direction 52 with the elapse of the operating time of the component mounting apparatus is measured. The points a to E are arranged at substantially equal intervals in the Y axis direction 52, and the X axis robot is moved from the front side to the rear side in the Y axis direction 52 by the Y axis robot, and the substrate recognition camera captures an image. Fig. 17 and 18 show the measurement results of the component mounting apparatus 100, and fig. 20 and 21 show the measurement results of the conventional component mounting apparatus. In addition, since the above-described point E does not exist in the conventional component mounting apparatus, the data of the point E is not found in fig. 20 and 21.

Fig. 17 shows the change in the amount of positional change of the points a to E in the Y-axis direction 52 with the elapse of the operating time of the component mounting apparatus 10. As is clear from fig. 17, the amount of change in position in the Y axis direction 52 at each of the points a to E increases with time, and after a predetermined time, the change in position saturates, and at any one time, the amount of change in position at the points a to E does not overlap and increases in the direction from a to E. Accordingly, it is understood that the X-Y robot 120 according to embodiment 1 expands only in the Y-axis direction 52 with the passage of time before a predetermined time, and the expansion is saturated after the passage of the predetermined time. Fig. 18 shows the amount of change in the position of the points a to E in the Y-axis direction 52 at each of the points a to c during the elapsed time shown in fig. 17. As is clear from fig. 18, for example, the amount of change in position at points a to E at time a changes substantially linearly, and this tendency is the same for times b and c. Accordingly, it is understood that the X-Y robot 120 expands in proportion to the distance along the Y-axis direction 52 regardless of the passage of time.

On the other hand, fig. 20 is a view corresponding to fig. 17, showing a case of the conventional component mounting apparatus. As is apparent from fig. 20, in the conventional component mounting apparatus, although the amount of change in position in the Y axis direction 52 at each of the points a-D becomes larger with the passage of time, the change in position is not saturated, and the amount of change in position at the point C, D is staggered. Fig. 21 shows the amount of change in the position of the points a to D in the Y-axis direction 52 at each of the times a to c during the elapsed time shown in fig. 20, but no linear change is observed at the times b and c. As is clear from fig. 20 and 21, the X-Y robot of the conventional component mounting apparatus not only expands in the Y-axis direction 52, but also has no linearity of displacement amount as time passes, that is, as temperature changes become larger.

Next, as shown in fig. 9 and 10, the component recognition camera 150 is a known system in which LEDs 151 as illumination light sources are arranged in the peripheral portion and an imaging camera 152 is arranged in the central portion, and images the electronic component 62 sucked and held by the component suction nozzle 1361 from below. In embodiment 1, as shown in fig. 1 and 2, the component recognition camera 150 is vertically provided on the base portion 111 of the stage 110.

Since the component recognition camera 150 uses the LED151 as a light source, the component recognition camera 150 generates less heat. In addition, since it is erected in the stage 110 formed in an integral structure by casting, the installation position of the component recognition camera 150 is not displaced by heat or is a negligible amount of displacement.

As shown in fig. 9 and 10, the camera reference mark 160 is arranged near the component recognition camera 150 and is a mark imaged by the substrate recognition camera 140 to determine thermal expansion and contraction of the X-Y robot 120 due to heat, that is, thermal expansion and contraction. Various forms of marks are conceivable, but as an example, as shown in fig. 10, a mark is formed by marking a circle in a square frame. The camera reference mark 160 is supported by a column 162 provided upright on the base portion 111 of the gantry 110 and is disposed at an imaging height position 161. The imaging height position 161 is a height position at which the distance between the substrate recognition camera 140 and the camera reference mark 160 in the Z-axis direction 53 is equal to the distance between the substrate recognition camera 140 and the substrate mark 61a in the Z-axis direction 53 when the substrate recognition camera 140 images the substrate mark 61a of the circuit substrate 61.

In this way, by disposing the camera substrate mark 160 at the imaging height position 161, the focal length of the substrate recognition camera 140 is equal when the substrate recognition camera 140 images the substrate mark 61a and when the camera reference mark 160 is imaged. Accordingly, the two captured images of the substrate mark 61a and the camera reference mark 160 have the same image quality, and a recognition error due to a difference in image quality can be eliminated.

Further, as shown in fig. 9, since the imaging height position 16 is a position protruding from the component recognition camera 150, the camera reference mark 160 is provided at a position not interfering with the imaging of the electronic component 62 by the component recognition camera 150.

The component supplying device 180 is a so-called cassette type component supplying device having a plurality of rollers around which a tape accommodating the electronic components 62 is wound in the component mounting device 100 of embodiment 1, and two sets are provided in each of the front side 100a and the rear side 100b of the component mounting device 100.

The substrate transport device 190 is a device for carrying in and out the circuit substrate 61 in the component mounting device 100, and is disposed substantially in the center of the component mounting device 100 in the X-axis direction 51 as shown in fig. 1 and the like.

As shown in fig. 11, the control device 170 is connected to the X-Y robot 120, the substrate recognition camera 140, the component recognition camera 150, the component supply device 180, and the substrate transfer device 190, which are the components, and controls the operations thereof to control the mounting operation of the electronic component 62 on the circuit board 61. The control device 170 includes a storage part 173 for storing a program required for the mounting operation and the like, and a function of the control device includes an expansion/contraction amount determination part 171 for obtaining the expansion/contraction amount of the X-Y robot 120 caused by heat based on the imaging information of the camera reference mark 160; and a base position specifying unit 172 for obtaining a relative positional relationship between the substrate recognition camera 140, the component recognition camera 150, and the component nozzle 1361 in advance. The operation of the control device 170 configured as described above will be described in detail.

Further, the operation of the component mounting apparatus 100 configured as described above, that is, the component mounting operation performed by the component mounting apparatus 100 will be described in detail with reference to fig. 12. In addition, since the operation of the circuit substrate conveying device 190 for conveying the circuit substrate 61 and the operation of the X-Y robot 120 including the component mounting head 140 from the suction of the component by the component supply device 180 to the mounting of the component on the circuit substrate 61 are substantially similar to those performed by the conventional component mounting device, these operations will be described briefly. Next, the determination operation of the amount of expansion and contraction of the X-Y robot 120 when heat is applied, which is performed using the camera reference mark 160, will be mainly described.

In steps 1 to 3 shown in fig. 12, various types of correction data are acquired as a preparation for continuously operating the component mounting apparatus 100.

That is, first, in step S1, the relative positional relationship between the component suction nozzle 1361, the substrate recognition camera 140, and the component recognition camera 150, that is, the misalignment between the center of the component suction nozzle 1361 and the center of the substrate recognition camera 140 in the X-axis direction 51 and the Y-axis direction 52, the misalignment between the center of the component suction nozzle 1361 and the center of the component recognition camera 150 in the X-axis direction 51 and the Y-axis direction 52, and the misalignment between the center of the substrate recognition camera 140 and the center of the component recognition camera 150 in the X-axis direction 51 and the Y-axis direction 52 are determined.

As described above, in the component mounting apparatus 100 according to embodiment 1, even if heat is applied, the component suction nozzle 1361 and the board recognition camera 140 are not displaced, the component recognition camera 150 is not displaced, or the component mounting accuracy is not negligible. Therefore, the misalignment measurement operation of step S1 may be performed once after the component mounting apparatus 100 is completed and before shipment, for example. Needless to say, the user of the component mounting device 100 may also perform, for example, before the start of daily operation or the like. The operation of step S1 is controlled by base position determining unit 172 of control device 170.

A specific method of determining the relative positional relationship between the component nozzle 1361, the substrate recognition camera 140, and the component recognition camera 150 will be briefly described.

That is, as shown in japanese patent application laid-open No. 8-242094, a nozzle center measuring jig is attached to the component nozzle 1361, and the nozzle center measuring jig is imaged by the component recognition camera 150 to obtain nozzle center measuring jig imaging information. Further, in order to be included in the imaging field of view of the component recognition camera 150, the camera center position measuring jig to which the imaging mark is added is attached to the component recognition camera 150, and the imaging mark is imaged by both the substrate recognition camera 140 and the component recognition camera 150 to obtain camera center measuring jig imaging information. Then, the relative positional relationship between the component nozzle 1361, the substrate recognition camera 140, and the component recognition camera 150 is determined based on the nozzle center measurement jig imaging information and the camera center measurement jig imaging information. By performing correction using the obtained relative positional relationship, the center of the component nozzle 1361 and the imaging center of the component recognition camera 150 are computationally matched, and the imaging center of the substrate recognition camera 140 can be arranged on a straight line passing through the center of the component nozzle 1361.

Further, as described above, the positional relationship between the component nozzle 1361 and the substrate recognition camera 140 in the obtained relative positional relationship is a displacement amount that is not changed or negligible by heat in the component mounting apparatus 100 according to embodiment 1, and as described in the description of the structure of the X-Y robot 120, the X-Y robot 120 is moved only in the Y-axis direction 52 and the X-axis direction 51 by heat, and does not generate deformation such as bending before. Therefore, after the component mounting apparatus 100 starts operating, in order to obtain the expansion and contraction of the X-Y robot 120 due to the thermal action, only the camera reference mark 160 may be imaged as described later, and the displacement amount obtained from the imaging result of the camera reference mark 160 may be regarded as the expansion and contraction amount of the X-Y robot 120. Accordingly, after the component mounting apparatus 100 starts operating, the amount of expansion and contraction of the X-Y robot 120 can be determined by the photographing operation of the camera reference mark 160. Thus, by correcting the mounting position in consideration of the amount of expansion and contraction, the electronic component 61 can be mounted at a predetermined mounting position with high accuracy.

In the following step 2, before the component mounting apparatus 100 starts a continuous mounting operation, for example, before a daily operation starts, the electronic component 62 is mounted on the circuit board 61 by a test, the mounting accuracy is measured, and the input mounting offset is set so that the central value of the difference of the mounting apparatus becomes a target value.

In the following step 3, for example, continuous aging is performed for about 1 hour, and after the component mounting apparatus 100 becomes a stable operation state, the camera reference mark 160 is photographed by the substrate recognition camera 140. The expansion/contraction amount determination unit 171 of the control device 170 determines the displacement between the center of the substrate recognition camera 140 and the center of the camera reference mark 160 in the X-axis direction 51 and the Y-axis direction 52, which are determined to be absolute positions in step 1, based on the camera reference mark imaging information. The expansion/contraction amount determination unit 171 stores the obtained misalignment information as an initial expansion/contraction amount of the reference position of the X-Y robot 120 before the start of the continuous operation.

The preparatory operation before the start of the continuous operation is completed by

steps

2 and 3. Thereafter, the continuous operation is performed through step 101-111.

The continuous movement of the component mounting device 100 is started by step 101. That is, after the circuit board 61 is carried in by the circuit board transport device 190 according to a mounting program such as NC data, the X-Y robot 120, the component mounting head 140, and the component supply device 180 are driven in step 103, and the electronic components 62 are sequentially mounted on the mounting positions of the circuit board 61. At this time, in step 102, the relative positional relationship between the component suction nozzle 1361, the substrate recognition camera 140, and the component recognition camera 150, which is obtained in step 1, is not limited to the amount of substrate displacement obtained by imaging the substrate mark 61a of the circuit substrate 61 with the substrate recognition camera 140 and the amount of part displacement obtained by imaging the electronic component 62 held by the component suction nozzle 1361 with the component recognition camera 150, and a correction amount with respect to the predetermined mounting position on the mounting program is obtained. The component displacement amount also includes a displacement angle of the electronic component 62 in the θ direction, which is an axial direction of the component nozzle 1361.

The component misalignment amount obtained by the imaging of the component recognition camera 150 is always the misalignment amount of the electronic component 62 with respect to the component suction nozzle 1361. That is, since the component nozzle 1361 holds the electronic component 62, the component recognition camera 150 can photograph the electronic component 62 but cannot photograph the component nozzle 1361 that is holding the electronic component 62. Thus, the component displacement amount obtained by the recognition operation of the component recognition camera 150 becomes the displacement amount of the electronic component 62 with respect to the component nozzle 1361 as described above. However, as described above, since the relative positional relationship between the component suction nozzle 1361 and the component recognition camera 150 is obtained by the operation of step 1, the amount of misalignment of the electronic component 62 with respect to the component suction nozzle 1361 may be known.

Further, the relative positional relationship between the board recognition camera 140 and the component recognition camera 150 is known by the operation of step 1, and as described above, in embodiment 1, a displacement amount that affects the component mounting accuracy does not occur between the component suction nozzle 1361 and the board recognition camera 140.

Accordingly, the misalignment information obtained by the substrate recognition camera 140 recognizing the camera reference mark 160 can be regarded as the misalignment information of the component recognition camera 150 and the component suction nozzle 1361 caused by the thermal expansion and contraction of the X-Y robot 120 in operation. That is, in order to determine the misalignment between the component recognition camera 150 and the component nozzle 1361 caused by the thermal expansion and contraction of the X-Y robot 120 during operation, the component mounting apparatus 100 may recognize the camera reference mark 160 by the board recognition camera 140.

As described above, in the component mounting apparatus 100 according to embodiment 1, since the camera reference mark 160 is recognized only for determining the misalignment between the component recognition camera 150 and the component suction nozzle 1361, it is not necessary to prepare the jig described in japanese patent application laid-open No. 8-242094 during the operation of the component mounting apparatus 100, and the operability can be improved compared to the conventional component mounting apparatus.

The amount of displacement between the component recognition camera 150 and the component nozzle 1361 obtained from the recognition operation of the camera reference mark 160 in this manner is used for the correction of the amount of displacement of the component obtained from the recognition operation of the component recognition camera 150 on the electronic component 62. That is, when the component displacement amount is obtained, the controller 170 uses the initial expansion/contraction amount of the X-Y robot 120 obtained in step 3 as a correction amount. That is, when the electronic component 62 held by the component nozzle 1361 is moved toward the component recognition camera 150, the initial expansion/contraction amount is corrected with respect to the predetermined movement amount in the mounting program, and the electronic component is moved. By performing this correction, the misalignment due to the thermal expansion and contraction can be eliminated, and the center of the component nozzle 1361 can be aligned with the center of the component recognition camera 150. Accordingly, when the component displacement amount obtained by the component recognition camera 150 and the board displacement amount are corrected, the electronic component 62 can be mounted at a predetermined mounting position on the mounting program. Accordingly, the operation controls the X-Y robot 120 and the component nozzle 1361 to perform component mounting so that the electronic component 62 is mounted at the predetermined mounting position in consideration of the correction (step 103).

As is apparent from the above description, in order not to cause an error due to the movement amount of the X-Y robot 120, it is preferable that the movement amount of the X-Y robot 120 for recognizing the camera reference mark 160 by the substrate recognition camera 140 and the movement amount of the X-Y robot 120 for recognizing the electronic component 62 held by the component nozzle 1361 by the component recognition camera 150 be as equal as possible. Thus, in embodiment 1, the component recognition camera 150 is disposed as close as possible to the camera reference mark 160.

As described above, when the component mounting operation is continued, it is determined whether, for example, 20 minutes, 40 minutes, or 60 minutes has elapsed since the component mounting apparatus 100 started to continuously operate in step 104. When these times have not elapsed, it is determined in step 105 whether or not the component mounting apparatus 100 is in a stopped state for, for example, 20 minutes after the start of continuous operation. When the predetermined time has elapsed in step 104 and the apparatus is stopped in step 105, it is considered that the X-Y robot 120 expands or contracts due to heating or cooling, and in step 106, the substrate recognition camera 140 again performs imaging of the camera reference mark 160. Then, the displacement between the center of the substrate recognition camera 140 and the center of the camera reference mark 160 in the X-axis direction 51 and the Y-axis direction 52 is determined again from the camera reference mark imaging information, and is set as a new expansion/contraction amount.

Next, in the following step 107, the expansion/contraction amount determination unit 171 compares the initial expansion/contraction amount obtained in the above step 3 with the new expansion/contraction amount obtained in the step 106. Then, when the difference value as the comparison result is equal to or larger than a set value, for example, 0.2mm or more of misalignment, a warning is issued as the occurrence of abnormal misalignment in step 109, and the execution apparatus is stopped. Further, as described above, since component mounting within an error range of, for example, ± 70 μm is currently required, occurrence of the above-described displacement of 0.2mm or more in the X-axis direction 51 or the Y-axis direction 52 due to heat is considered as occurrence of an abnormality.

On the other hand, if the difference value as the comparison result is less than the set value, it is considered that the new expansion/contraction amount is caused by expansion/contraction of the X-Y robot 120 due to heat generated during operation. Accordingly, step 108 updates the new expansion/contraction amount obtained this time as the initial expansion/contraction amount.

The reason why only the result of the substrate recognition camera 140 capturing the camera reference mark 160 is regarded as the amount of expansion and contraction of the X-Y robot 120 in the X-axis direction 51 or the Y-axis direction 52 due to heat is as described above.

In step 105, when the apparatus does not stop for the predetermined time, and after the updating operation of the new expansion/contraction amount is completed in step 108, the process proceeds to step 102 again.

Thereafter, in step 110, it is determined whether or not the component mounting is finished for all the set number of circuit boards 61, and when the component mounting is finished, the process moves to step 111, and the apparatus is stopped. On the other hand, if not yet finished, the process returns to step 102 again.

The component mounting action is performed as described above.

Next, the improvement of the component mounting accuracy of the component mounting apparatus 100 described above over the conventional one will be described with reference to experimental data.

In fig. 22 and 23, the component mounting apparatus 100 operates the X-Y robot 120 at an atmospheric temperature of 20 degrees, images the camera reference mark 160 with the substrate recognition camera 140, and performs the correction at step 102 and the correction at step 106. After that, the temperature of the atmosphere was decreased to 10 degrees, and then changed to 30 degrees in 5 degrees. Under such conditions, the amount of displacement of the camera reference mark 160 recognized by the board recognition camera 140 and the amount of displacement of the center value of the mounting accuracy are measured at each temperature. Fig. 22 shows the measurement results in the Y-axis direction 52, and fig. 23 shows the measurement results in the X-axis direction 51. As is clear from fig. 22 and 23, even when the atmospheric temperature changes, the displacement amount of the camera reference mark 160 and the displacement amount of the center value of the mounting accuracy substantially match each other in both the Y-axis direction 52 and the X-axis direction 51, and the expansion and contraction of the X-Y robot 120 due to heat occurs only in the Y-axis direction 52 and the X-axis direction 51.

As described above, according to component mounting apparatus 100 of embodiment 1, since the thermal expansion and contraction of X-Y robot 120 only occur in Y-axis direction 52 and X-axis direction 51, and no rotational misalignment to the periphery of the Z-axis occurs, camera reference mark 160 provided in proximity to component recognition camera 150 is sufficient as described above as one mark, and it is not necessary to arrange two camera reference marks for 1 component recognition camera and determine the rotational misalignment angle by recognizing the two camera reference marks.

In addition, differences in the component mounting positions with the passage of the operating time of the component mounting time are shown in fig. 25 to 27. The origin at the center of the curve indicates that the error between the predetermined mounting position and the actual mounting position is zero, and if the drawing is concentrated near the origin, this means that the difference is small. Fig. 26 shows a case of a conventional component mounting apparatus, in which the center of the difference range is shifted from the origin and the range is widened as the operating time passes. Accordingly, it is known that the conventional component mounting apparatus increases the amount of misalignment with the elapse of the operating time. Fig. 27 shows the above-described difference when the camera reference mark 160 is provided in the conventional component mounting apparatus and correction is performed based on the camera reference mark 160. In the case of fig. 27, the range of the difference is narrowed as compared with the case of fig. 26, but the center of the range of the difference is still deviated from the above-described origin. On the other hand, fig. 25 shows the case of the component mounting device 100 of embodiment 1, in which the center of the difference range is located near the above-described origin, and the difference range is not widened. As described above, as is apparent from fig. 25, the component mounting apparatus 100 according to embodiment 1 can perform component mounting with higher accuracy than before.

Next, a modification of the component mounting apparatus 100 will be described.

In the component mounting apparatus 100, only the component supply apparatus 180 of the tape cassette having the reel is provided, but a configuration of the component mounting apparatus 101 shown in fig. 24, for example, may be adopted. In fig. 24, the X-axis robot 131 is not shown for convenience of illustration. The component mounting apparatus 100 may also include a so-called tray type component supply unit 181 to supply large components and the like. In addition, in addition to the component recognition camera 150, a 2D component recognition camera 153 capable of two-dimensionally obtaining a captured image of the electronic component 61 held by the component nozzle 1361 and having a resolution higher than that of the component recognition camera 150 is provided; and a 3D part recognition camera 154 capable of obtaining a captured image of the electronic part 61 in 2 dimensions. In addition, since the component recognition camera 150 is disposed at the front side 100a and the 2D component recognition camera 153 and the 3D component recognition camera 154 are disposed at the rear side 100b, one more camera reference mark 160 is disposed near the 2D component recognition camera 153 and the 3D component recognition camera 154.

The electronic component 62 sucked from the

component supply devices

180 and 181 disposed on the rear side 100b may be imaged by the component recognition camera 150, and the electronic component 62 sucked from the component supply device 180 disposed on the front side 100a may be imaged by the 2D component recognition camera 153 and the 3D component recognition camera 154.

In addition, since the resolution of the 2D part recognition camera 153 is good, when necessary accuracy is obtained from the imaging result of the 2D part recognition camera 153, the imaging by the part recognition camera 150 can be omitted.

As described above, when the plurality of camera reference marks 160 are provided, the result of measuring the position of one camera reference mark 160 among the plurality of camera reference marks 160 is performed, and as a result of the determination performed in step 107, when the difference value is less than the set value, the position measurement of the other camera reference marks 160 may be omitted.

As described above in detail, according to the component mounting apparatus of the 1 st aspect and the component mounting method of the 2 nd aspect of the present invention, there is provided an X-Y robot having a structure that deforms linearly in the X-axis direction and the Y-axis direction when heat is applied and the relative position of the component holding member and the substrate recognition camera does not change; a camera fiducial marker; and a control device for recognizing the camera reference mark by the substrate recognition camera before and after the X-Y robot is deformed by heat, obtaining the expansion amount of the X-Y robot caused by heat, and correcting the component mounting position according to the expansion amount. As described above, since the X-Y robot is linearly deformed only in the X-axis direction and the Y-direction without generating displacement such as bending even if heat is applied by continuous operation, when the component mounting position is corrected based on the amount of expansion and contraction of the X-Y robot due to heat, which is obtained by photographing the reference mark of the camera, the component can be mounted with higher accuracy than before. As described above, according to the component mounting apparatus and method of the above-described 1 st and 2 nd aspects, component mounting accuracy can be improved as compared with the conventional one.

In addition to the relative positions of the component holding device, the board recognition camera, and the component recognition camera for imaging the electronic component held by the component holding device, the component can be mounted with higher accuracy by correcting the component mounting position.

Further, a Y-axis robot of an X-Y robot having a Y-ball screw structure which extends and contracts only in a Y-axis direction is formed on a stage formed in an integral structure by casting, so that the extension and contraction of the Y-axis robot during heat application can be set only in the Y-axis direction.

Further, by fitting an X-ball screw structure that expands and contracts only in the X-axis direction due to heat into an X-frame having both ends fixed to the Y-axis robot, the X-ball screw structure can be expanded and contracted in the X-axis direction when heat is applied.

In addition, by fitting the deformation preventing member to the above-described X-frame, the X-frame can be prevented from being deformed such as bent due to heat, and the X-Y robot can be facilitated to be linearly deformed only in the X-axis direction and the Y-axis direction.

In addition, since the driving source for moving the component holding member in the Z-axis direction is provided in each of the component holding members provided in the component mounting head, it is possible to prevent the occurrence of a temperature gradient in the component mounting head, to prevent the occurrence of a displacement in the distance between the component holding members, and to contribute to the improvement of the above-described component mounting accuracy.

Further, since the camera reference mark and the circuit board are at the same height, the focal length of the substrate recognition camera when the camera reference mark and the circuit board mark are picked up by the camera can be made equal, and the occurrence of an error due to the blurring of the picked-up image can be prevented.

By disposing the camera reference mark close to the component recognition camera, the movement amount of the X-Y robot between the operation of the component recognition camera for photographing the electronic component and the operation of the substrate recognition camera for photographing the camera reference mark can be reduced, and the increase of error accompanying the movement of the X-Y robot can be reduced.

The present invention is not limited to the above-described embodiments, and can be implemented in various other embodiments. For example, the following configuration is also possible.

As shown in fig. 31 to 34, the component mounting apparatus 100 capable of implementing the component mounting method according to embodiment 2 of the present invention includes a stage 110, an XY robot 120, a substrate recognition camera 140, a component recognition camera 150, and a control device 170, and may include a component supply device 180 and a substrate transport device 190.

The stage 110 is a base stage for installing the X-Y robot 120, the component recognition camera 150, the control device 170, the component supply device 180, and the substrate transfer device 190, and is composed of a rectangular parallelepiped base portion 111 and a Y-axis robot leg portion 112, and the base portion 111 and the Y-axis robot leg portion 112, that is, the stage 110, are molded in an integral structure by casting. The Y-axis robot leg portion 112 is provided along the X-axis direction 51 so as to protrude from the base portion 111 at both ends of the base portion 111, and extends along the Y-axis direction 52 orthogonal to the X-axis direction 51. A linear guide 123 and the like in a Y-axis robot 121 described later in detail constituting the X-Y robot 120 are provided in each Y-axis robot leg 112. The respective linear guides 123, which are guide support members of the nut portion 126 of fig. 34, are provided on the Y-axis robot leg portions 112 along the linear guide installation surfaces 123a formed in the respective Y-axis robot leg portions 112 in the Y-axis direction 52, but as described above, the respective Y-axis robot leg portions 112 and the base portion 111 are molded in an integral structure by casting.

The X-Y robot 120 includes two Y-axis robots 121 provided in parallel to each other in the Y-axis direction 52 on the respective Y-axis robot legs 112, i.e., the gantry 110 formed in an integral structure by casting, and one X-axis robot 131 arranged on the two Y-axis robots 121 in the X-axis direction 51 orthogonal to the Y-axis direction 52.

Each Y-axis robot 121 has the Y-ball screw structure 122 and the linear guide 123 described above. The Y-ball screw structure 122 is configured to extend and contract linearly only in the Y-axis direction 52 by heat while moving the X-axis robot 131 in the Y-axis direction 52, with one end 122a being a fixed end and the other end 122b being a support end. Specifically, as shown in fig. 31 and 34, a motor 124 as a driving source of a ball screw 125 fixed to the Y-axis robot leg 112 is provided at the one end 122a of the Y-ball screw structure 122, and is coupled to the ball screw 125. The other end 122b is rotatably supported in the circumferential direction thereof and telescopically supports a ball screw 125 in the axial direction thereof, i.e., the Y-axis direction 52, and is attached to the Y-axis robot leg 112.

When the Y-axis robot 121 thus configured is continuously operated, the heat generating portions are the ball screw 125 and the motor 124, and the other end 122b allows the thermally induced expansion and contraction of the ball screw 125 in the Y-axis direction 52. Since the motor 124 is fixed to the gantry 110 having an integral structure as described above, the thermal expansion and contraction of the Y-axis robots 121 due to heat, i.e., the thermal expansion and contraction, are linear only in the Y-axis direction 52. Since the two Y-axis robots 121 operate in the same manner, the thermal expansion and contraction amounts of the respective Y-axis robots 121 in the Y-axis direction 52 are equal.

As shown in fig. 34, a nut portion 126 is attached to the ball screw 125 of each Y-axis robot 121, and the nut portion 126 is moved in the Y-axis direction 52 by the rotation of each ball screw 125. An X-axis robot 131 constituting the X-Y robot 120 is disposed between the nut portions 126 in the X-axis direction 51. As described above, since the Y-axis robots 121 expand and contract in the Y-axis direction 52 by the same amount, the X-axis robot 131 provided between the nut portions 126 can move in the Y-axis direction 52 in parallel with the X-axis.

Fig. 34 schematically shows the structures of the gantry 110 and the X-Y robot 120, and the component mounting heads described later are not shown. In fig. 32 to 34, illustration of the component supply device 180 is omitted.

The X-axis robot 131 has an X-frame 132 and an X-ball screw configuration 133. As described above, the X-frame 132 has both ends fixed to the nut portions 126 of the ball screw structures 122 of the respective Y-axis robots 121 and extends in the X-axis direction 51. The X-ball screw structure 133 is formed in the X-frame 132, and has one end 133a as a fixed end and the other end 133b as a support end, and is configured to linearly expand and contract only in the X-axis direction 51 by heat, and a component mounting head 136 as an example of a component holding head is attached, and the component mounting head 136 is moved in the X-axis direction 51.

The X-frame 132 is a member made of aluminum having a substantially square column shape, and both ends thereof are fixed to the nut portions 126 as described above. As shown in fig. 34, a motor 135 as a driving source of a ball screw structure 134 fixed to the X-frame 132 is provided at the one end 133a of the X-ball screw structure 133 formed on the side surface of the X-frame 132, and is connected to the ball screw 134. The other end 133b rotatably supports a ball screw 134 in the circumferential direction and telescopically in the axial direction, i.e., the X-axis direction 51, and is attached to the X-frame 132. When the X-axis robot 131 is continuously operated, the heat generating portions are the ball screw 134 and the motor 135, and the other end 133b allows the thermally induced expansion and contraction of the ball screw 134 in the X-axis direction 51.

As shown in fig. 31, a nut 134a for mounting the component mounting head 136 is mounted on the ball screw 134, and the nut 134a, that is, the component mounting head 136 is moved in the X-axis direction 51 by the rotation of the ball screw 134.

The component mounting head 136 has a component nozzle 1361 as an example of realizing a function of holding a component as a component holding element for holding the electronic component 62; and a substrate recognition camera 140 for imaging the substrate reference position calculation marks 202-1 and 202-2 existing on the circuit substrate 61 in order to confirm the displacement of the circuit substrate 61 carried in and set up in embodiment 2, and also for imaging the mounting region reference marks 201 arranged at predetermined intervals on the mounting region reference mark recognition reference substrate 200 described later. As shown in fig. 35, in

embodiment

2, 8 component nozzles 1361 are provided in a straight line in the X-axis direction 51. The electronic component 62 is a small component such as a chip component, a large component such as QFP, or the like. Thus, the component nozzle 1361 is also equipped with a nozzle of an optimal size and shape corresponding to various components to be sucked. As described above, the substrate recognition camera 140 is disposed such that the imaging center of the substrate recognition camera 140 is located on the same axis as a straight line passing through the centers of the respective nozzles 1361 arranged in the X-axis direction. Further, the component mounting head 136 is provided with a rotating motor 1363 for rotating the component nozzles 1361 in the axial direction thereof.

Since the component suction nozzle 1361 sucks the electronic component 62 from the component supply device 180 and mounts the sucked electronic component 62 on the circuit board 61 which is an example of a circuit board for component mounting, it is necessary to move in the Z-axis direction 53 which is the axial direction of the component suction nozzle 1361. In embodiment 2, in the component mounting head 136, in order to move the component nozzle 1361 which is an example of the component holding component, a moving motor 1362 which is an example of a driving source for moving the component holding component is provided in the component nozzle 1361. Thus, compared with the conventional case where all of the plurality of component nozzles are driven by one large-output motor, a motor with a low output can be used, and the amount of heat generated from the motor can be suppressed. In one embodiment, the output of the moving motor 1362 is 20W, and heat is not substantially generated from the moving motor 1362. In addition, in the case where the large output motor having a large amount of heat generation is provided in the past, the conventional component mounting head generates a temperature gradient in accordance with the distance from the large output motor, and the distance between the suction nozzles of the respective components in the arrangement direction is different depending on the thermal expansion and contraction. In contrast, in embodiment 2, by providing the moving motor 1362 in each component nozzle 1361, heat generation from each moving motor 1362 is substantially absent, and even if heat generation is assumed, the component mounting head 136 does not generate a temperature gradient that affects the degree of component mounting accuracy. Thus, even if the component mounting head 136 is continuously run, the distances between the component nozzles 1361 in the X-axis direction 51 can be maintained in an equal or substantially equal state. The substantially equal state is a state that does not affect the component mounting accuracy.

The component supplying device 180 is a so-called cassette type component supplying device having a plurality of rollers around which a tape accommodating the electronic components 62 is wound in the component mounting device 100 of embodiment 2, and two sets are provided in each of the front side 100a and the rear side 100b of the component mounting device 100.

The substrate transport device 190 is a device for carrying in, sucking, holding, and carrying out the circuit substrate 61 with respect to the mounting position of the circuit substrate 61 in the component mounting area in the component mounting device 100, and is disposed in a substantially central portion of the component mounting device 100 along the X-axis direction 51 as shown in fig. 31 and the like. The substrate transport device 190 has a transport table 165 as an example of a substrate holding device at the mounting position, and can hold the circuit substrate 61 that can be carried in by suction, while releasing the suction holding and carrying out the circuit substrate 61.

As shown in fig. 36, the control device 170 is connected to the X-Y robot 120, the substrate recognition camera 140, the component recognition camera 150, the component supply device 180, and the substrate transfer device 190, which are the components, and controls the operations thereof to control the mounting operation of the electronic component 62 on the circuit board 61. The control device 170 includes a storage unit 173 for storing mounting information such as a program and mounting data required for the mounting operation (for example, data such as moving position coordinate data of each component mounting head 136 during the mounting operation, mounting position coordinate data of each component, relationship information between the moving position of each component mounting head 136 and the mounting position of each component, size of a mounting area reference mark recognition reference substrate or position coordinate data of a mounting area reference mark, position coordinate data of a mark to be mounted or position coordinate data of a substrate reference position calculation mark, data such as each component data and the size of a suction nozzle, component supply data of the component supply device 180), identification information of the substrate recognition camera 140, or a calculation result of the calculation unit 171, and includes a calculation unit 171 for performing various calculations based on the identification information of the substrate recognition camera 140 (for example, the substrate recognition camera 140 recognizes the mounting area reference mark 201A, 201B, information on the mounting area reference mark 201 recognized by the substrate recognition camera 140, information on the substrate reference position calculation marks 202-1 and 202-2 recognized by the substrate recognition camera 140, and the like) and calculates the parallel shift, the tilt, the amount of expansion and contraction, and the like, and calculates an error at each mounting position based on the recognition information and each mounting position data in the mounting information stored in the storage unit 173. The control device 170 executes the component mounting operation based on the data or information stored in the storage unit 173. The component mounting operation, particularly the correction operation, of the control device 170 configured as described above will be described in detail below.

The operation of the component mounting apparatus 100 configured as described above, that is, the component mounting operation performed by the component mounting apparatus 100 will be described in detail. In addition, since the operation of the circuit substrate conveying device 190 for conveying the circuit substrate 61 and the operation of the X-Y robot 120 including the component mounting head 136 from the suction of the component by the component supply device 180 to the mounting of the component on the circuit substrate 61 are substantially similar to those performed by the conventional component mounting device, these operations will be briefly described below.

That is, the component mounting head 136 is moved to the component supply device 180 by the XY robot 120. Next, one or more electronic components 62 are suction-held from the component supply device 180 by one or more nozzles 1361 of the component mounting head 136. Thereafter, the component mounting head 136 passes above the component recognition camera 150 by the XY robot 120, recognizes the posture or the like of the electronic component 62 sucked and held by the suction nozzle 1361 by the component recognition camera 150, and then, faces the mounting device of the circuit board 61. After the electronic component 62 sucked and held by one nozzle 1361 of the component mounting head 136 is positioned above the corresponding mounting device by the XY robot 120, the nozzle 1361 is lowered to mount the electronic component 62 at the mounting position. At this time, the mounting operation is executed by performing the mounting operation described above while rotating the nozzle 1361 around its axis or the like based on the result of the component posture recognition by the component recognition camera 150 and performing the position correction of the component mounting head 136 in consideration of the offset value described later. The series of mounting operations is executed for all the components 62 mounted on the substrate 61.

The component mounting method of embodiment 2 is characterized by the position correcting operation of the component mounting head 136 in the above-described mounting operation in consideration of the offset value, and is described in detail below with reference to fig. 41.

That is, the component mounting method of embodiment 2 recognizes the mounting area reference marks 201 arranged at predetermined intervals on the glass substrate 200 as an example of the mounting area reference mark recognition reference substrate, obtains the position coordinates of each of the recognized mounting area reference marks (coordinates consisting of an X-coordinate value in the X direction and a Y-coordinate value in the Y direction orthogonal to the X direction in the plane of the glass substrate 200 for indicating the position of the mounting area reference mark), obtains the difference between the NC coordinates (numerical position coordinates of the mounting area reference mark predetermined in design) of each of the mounting area reference marks and the position coordinates, obtains the NC coordinates of the position coordinates of at least two substrate reference position calculation marks of the component mounting circuit substrate as correction values, and from the recognized mounting area reference marks, the position coordinates of the extracted mounting area reference marks are coordinate-converted so that the correction values of the extracted mounting area reference marks are zero or substantially zero, and the offset values under the respective mounting area reference marks are obtained. Then, in a state where the component mounting circuit board is held by the board holding device in place of the mounting area reference mark recognition reference board and positioned in the component mounting area, the at least two board reference position calculation marks of the component mounting circuit board held by the board holding device are recognized, respectively, position coordinates of the recognized two board reference position calculation marks are obtained, respectively, the NC coordinates of the two board reference position calculation marks are corrected, respectively, based on the obtained position coordinates of the two board reference position calculation marks, respectively, and, when the mounting position correction, the mark recognition correction, the mounting position deviation measurement operation, or any of these operations is located at each of the movement positions of the component mounting head 136, the offset value of the mounting area on the recognition camera closest to the component holding head is based on the offset value of the mounting area on the recognition camera provided in the component holding head, the position coordinate correction of the above-described movement position is performed, thereby performing mounting with high accuracy.

Here, the offset value is a value for correcting the position coordinates of the mounting area reference mark obtained by coordinate-converting the position coordinates of the extracted mounting area reference mark so that the correction value of the mounting area reference mark extracted as the mounting area reference mark of the two substrate reference position calculation marks respectively adjacent to the component mounting circuit board becomes zero or substantially zero, as will be described later.

The correction value is a difference between each NC coordinate of the mounting area reference mark arranged at predetermined intervals on the reference substrate and the recognized position coordinate.

First, an exemplary offset value calculation method will be described.

The positioning accuracy of the component mounting head 136 is greatly affected by the deformation of the XY robot 120 (see fig. 37 and 38), and a positioning error occurs. For example, fig. 37 is a diagram showing a relationship between the deformation of the X-axis robot and the component mounting head 136, and fig. 38 is a diagram showing a relationship between the deformation of the Y-axis robot and the component mounting head 136. This positioning error varies with the position at which the component mounting head 136 moves, and affects the mounting accuracy. Therefore, as shown in fig. 39, as a numerical value for correction for removing an error such as positioning of the XY robot 120 occurring when the XY robot 120 moves the head 136 to an arbitrary NC coordinate position, an offset value of the mounting area reference mark position closest to the NC coordinate position (in other words, an offset value for correction of an area where the NC coordinate position exists) is used. That is, in the maximum component mounting area (area including the substrate to be produced, for example, a substrate having an XL size of 510mm × 460mm and a substrate having an M size of 330mm × 250mm), an offset value used as a correction value for correcting an error such as positioning is obtained using the reference substrate for recognition of the reference mark of the mounting area.

Specifically, first, in step S1 of fig. 41, the glass substrate 200, which is an example of a reference substrate for identifying a reference mark in the mounting region, is held on the conveyance table 165, which is an example of a substrate holding device, and is positioned in the component mounting region.

Next, in step S2 of fig. 41, the substrate recognition camera 140 of the component mounting head 136 recognizes the position coordinates of all the mounting region reference marks 201 arranged at predetermined intervals on the glass substrate 200 held on the conveying table 165. Here, more specific identification of the mounting region reference mark for measuring the correction value is performed as follows. In the measurement of the correction value, as an example of the reference substrate for identifying the reference mark in the mounting region of the measurement substrate, the correction value is calculated by the following equation in terms of the XL size: for the glass substrate 200 of 510mm × 460mm (M size: 330mm × 250mm), a dedicated glass substrate (hereinafter referred to as a glass substrate) is used in which mounting region reference marks (circles having a diameter of 1mm)201 are formed in a grid shape (lattice shape) by printing or the like. That is, as an example of the glass substrate 200, as shown in fig. 40, a glass substrate having an XL size of 510mm × 460mm was used, and the Y direction: 44 rows, X direction: 49 columns of substrates with circular mounting area reference marks (1 mm in diameter) 201. Thus, the number of mounting area reference marks used for measurement was 2156 points. On a glass plate having an M size of 410mm × 240mm, circular mounting area reference marks (diameter of 1mm)201 were arranged at a pitch of 10mm in the Y direction: 22 rows, X direction: the mounting area reference marks 201 of the 39 columns are used for measurement. Thus, the number of mounting area reference marks used for measurement was 858 points.

In principle, the size of the mounting region reference mark recognition reference substrate may be any size as long as it is equal to or larger than the maximum component mounting region of the component mounting apparatus, but as described later, when it is smaller than the maximum component mounting region, it may be virtually equal to or larger than the maximum component mounting region by using a synthesis method. When the interval between the mounting region reference marks is made narrow, the accuracy is improved, but the data acquisition time becomes long and the data storage amount becomes large. Therefore, it is economically sufficient to make the guide member of the ball screw structure of the XY robot 1/4-1/5 degrees. As a specific example, the mounting region reference mark pitch is set to 10mm with respect to 40mm of the guide.

Next, in step S3 of fig. 41, the position coordinates of each of the mounting region reference marks 201 thus recognized are obtained by the arithmetic unit 171 based on the recognition result, and stored in the storage unit 173. That is, as shown in fig. 43, for example, in order to reduce the misalignment, the entire mounting area reference marks 201 are moved parallel to the substrate conveying direction of the substrate conveying device 190 from the left end mounting area reference mark 201 on the lowermost row by the substrate recognition camera 140 of the head 136 to the right end mounting area reference mark 201 on the same row, all the mounting area reference marks 201 on the row are sequentially recognized, and the position coordinates are obtained by the arithmetic unit 171 based on the recognition result and stored in the storage unit 173. Next, after the oblique left-hand reverse movement, the substrate recognition camera 140 of the head 136 is moved from the left-end mounting region reference mark 201 of the upper row of the lowermost row to the right-end mounting region reference mark 201 of the same row, and all the mounting region reference marks 201 of the row are sequentially recognized, and based on the recognition result, the position coordinates are obtained by the arithmetic unit 171 and stored in the storage unit 173. After the substrate recognition camera 140 of the head 136 is moved in the oblique left-right direction, the substrate recognition camera is moved from the left end mounting area reference mark 201 of the two upper rows of the lowermost row to the right end mounting area reference mark 201 of the same row, all the mounting area reference marks 201 of the row are sequentially recognized, and the position coordinates are obtained by the arithmetic unit 171 based on the recognition results and stored in the storage unit 173. In this order, all the mounting area reference marks 201 in all the rows are recognized, and the position coordinates are obtained by the calculation unit 171 based on the recognition results and stored in the storage unit 173. The lower side of the glass substrate 200 in fig. 43 corresponds to the front side of the component mounting apparatus, i.e., the front side of the operator.

In order to improve the recognition accuracy of each mounting region reference mark 201, the recognition process of each mounting region reference mark 201 may be repeatedly performed a plurality of times. At this time, the average value of the position coordinates obtained by the recognition result of the magnitude of the number of times is calculated by the calculating unit 171 and stored in the storage unit 173 as the position coordinates of each mounting area reference mark 201. The number of times can be arbitrarily changed from the operation screen of the component mounting apparatus.

In this way, the position coordinates of all the mounting region reference marks 201 are stored in the storage unit 173.

Next, in step S4 of fig. 41, the difference between the NC coordinates and the position coordinates of each of the mounting area reference marks 201 is obtained by the arithmetic unit 171 and stored as a correction value in the storage unit 173. The correction value is a value for correcting a holding misalignment of the glass substrate 200, a recognition misalignment, a positioning error with the XY robot, and the like when the glass substrate 200 is suction-held by the conveyance table 165.

Next, in step S5 of fig. 41, the NC coordinates of the position coordinates of at least two substrate reference position calculation marks 202-1 and 202-2 of the component mounting circuit substrate 61 are acquired by the arithmetic unit 171.

Then, in step S6 of fig. 41, the mounting region reference marks 201 of the two substrate reference position calculation marks 202-1 and 202-2 respectively adjacent to the component mounting circuit substrate 61 are extracted from the recognized mounting region reference marks 201 of the glass substrate 200 by the arithmetic unit 171 based on the NC coordinates of the position coordinates of the two substrate reference position calculation marks 202-1 and 202-2, respectively. Specifically, in fig. 42, while the head 136 is moved by the XY robot 120, the substrate recognition camera 140 recognizes the mounting area reference marks 201A and 201B at two points located on, for example, upper right and lower left diagonal corners on the glass substrate 200, which are respectively close to the two substrate reference position calculation marks 202-1 and 202-2. That is, it is difficult to hold the glass substrate 200 on the conveyance table 165 completely parallel to the substrate conveyance direction of the substrate conveyance device 190, and a misalignment occurs. In order to correct the misalignment when the glass substrate is held, first, mounting area reference marks 201 at the lower left corner and the upper right corner of the glass substrate 200 are recognized as mounting area reference marks 201A and 201B.

Next, in step S7 of fig. 41, the position coordinates of the extracted mounting area reference marks 201A and 201B are subjected to coordinate transformation (coordinate transformation in consideration of the parallel misalignment, the inclination, and the expansion/contraction ratio) so that the correction values of the extracted mounting area reference marks 201A and 201B become zero or substantially zero, and the offset values under the respective mounting area reference marks 201A and 201B are obtained. That is, the calculation unit 171 obtains the parallel displacement and inclination of the glass substrate 200 from the position coordinates of the recognition results of the two point mounting region reference marks 201A and 201B obtained in step S3 of fig. 41. The method of determining the parallel misalignment and the tilt is described below. Parallel misalignment refers to misalignment in the X-direction and/or Y-direction. The inclination refers to a rotational misalignment caused by rotation in the X direction and the Y direction, which is a direction perpendicular thereto, when the substrate stopper stops the substrate at the mounting position of the transfer table 165. In this case, since the normal mark correction for substrate reference position calculation requires consideration of the substrate expansion and contraction due to heat, the expansion and contraction rate is also determined, but when the glass substrate 200 is set as a reference without consideration of the substrate expansion and contraction due to heat, the expansion and contraction rate of the glass substrate 200 is set to 1. Here, the expansion/contraction ratio is a ratio of expansion/contraction due to heat to the substrate itself.

Next, the calculation unit 171 performs coordinate transformation by curvilinearly rotating and moving the mounting area reference marks 201A and 201B connecting the two points based on the obtained correction values (parallel offset and inclination) so that the correction values of the mounting area reference marks 201A and 201B at the two points become zero (in other words, coincide with the data of the NC coordinates of the mounting area reference marks 201A and 201B at the two points) or substantially zero (for example, within a range of ± 5 μm), obtains offset values of the position coordinates of all the mounting area reference marks 201, and stores the offset values in the storage unit 173. As a result, the offset value of each region corresponding to the size of the mounting region reference mark recognition reference substrate [ a rectangular region in which the reference substrate is divided per unit area based on the mounting region reference mark (for example, surrounded by the mounting region reference mark of 4 points) ] can be determined, the offset value of each region is used as a value for correcting the movement position of the component mounting head existing in each region, and the offset value is used for correcting the position of the component mounting head in each mounting region reference mark recognition reference substrate during a recognition operation of each mounting region reference mark of the mounting region reference mark recognition reference substrate and during a component mounting operation of the corresponding mounting substrate, whereby improvement of mounting accuracy can be achieved.

Errors in positioning and the like inherent to the XY robot 120 can be grasped as relative changes between the respective mounting positions by the offset values obtained in steps S1 to S7 in fig. 41 in the above-described steps. The offset value thus obtained can be used as a correction value for correcting position coordinates at the time of the mounting area reference mark recognition operation, the component mounting operation, and the mounting offset value measurement operation, or at the time of calculating the head positioning position of each of these operations, and can absorb a displacement factor due to the operation deformation of the XY robot, thereby improving the mounting accuracy.

Here, the reason why the correction based on the positional deviation of the mounting area reference mark recognition reference substrate is added to the positional coordinates of all the mounting area reference marks 201 is that the positional error of the XY robot 120 is included in the mounting area reference mark recognition when the correction value is measured. In the first place, errors are included in the positioning operations of all the XY robots 120, and even if the glass substrate 200 can be manufactured with desired high accuracy, the mounting position of the component mounting apparatus cannot be accurately determined, and there is no absolute reference, so that it is impossible to accurately measure the positioning errors of the XY robots 120.

Here, the reference will indicate that the position is at the center O of the field of view away from the substrate recognition camera 140₁、O₂When the recognition results of the mounting area reference marks 201A and 201B at the time of mounting area reference mark recognition are set in fig. 44 in which the mounting area reference marks 201A and 201B are recognized at the positions of (1), a positional coordinate deviation (Δ X) obtained from the recognition result of the mounting area reference mark 201A at the 1 st point is obtained₁、ΔY₁) Mounting area according to point 2Positional coordinate displacement (Δ X) obtained as a result of recognition of the domain reference mark 201B₂、ΔY₂) The positional coordinate obtained from the mounting region reference mark recognition result is displaced.

As the displacement component included in the positional coordinate displacement obtained from each recognition result, it is originally preferable that only the amount of parallel displacement is obtained when the glass substrate 200 is held on the conveyance table 165, but actually, the attenuation of the recognition process and the positioning error of the XY robot 120 are included. Therefore, the positional coordinate displacement obtained from the recognition result of the mounting region reference marks 201A and 201B becomes the positional coordinate displacement

(positional coordinate displacement of recognition result) (positional displacement of substrate holding) + (positional displacement of recognition) + (XY robot positioning error),

the substrate parallel displacement amount of each mounting

region reference mark

201A, 201B is (X)_pcb1，Y_pcb1)、(X_pcb2，Y_pcb2) The recognition error of the mounting region reference marks 201A and 201B is (X)_rec1，Y_rec1)、(X_rec2，Y_rec2) The amount of positioning error of the XY robot 120 under the mounting area reference marks 201A, 201B is set to (X)_e1，Y_e1)、(X_e2，Y_e2) Then, the position coordinate deviation (Delta X) obtained from the recognition result is calculated₁、ΔY₁)、(ΔX₂、ΔY₂) Become into

[ formula 1]

ΔX₁＝X_pcb1+X_rec1+X_e1

ΔY₁＝Y_pcb1+Y_rec1+Y_e1

ΔX₂＝X_pcb2+X_rec2+X_e2

ΔY₂＝Y_pcb2+Y_rec2+Y_e2

That is, using the above recognition result, the position coordinates of the mounting area reference mark obtained by correcting the position coordinates of each mounting area reference mark 201 by the amount of positional coordinate displacement of the glass substrate 200 do not actually constitute the coordinates where the mounting area reference mark 201 exists. This is because the positional coordinates of the corrected mounting region reference mark include a displacement amount due to a positioning error of the XY robot 120.

An error (X) in recognition of the mounting region reference marks 201A, 201B is assumed_rec1，Y_rec1)、(X_rec2，Y_rec2) When the mounting area reference mark 201 is zero, the NC coordinate of the mounting area reference mark 201 is (X)_mnc，Y_mnc) The NC coordinates of the mounting area reference marks 201A and 201B are (X)_nc1，Y_nc1)、(X_nc2，Y_nc2) Position coordinates (X) of the mounting region reference mark obtained after correction_m，Y_m) Is composed of

[ formula 2]

X_m＝(X_mnc-X_nc1)cosΔθ-(Y_mnc-Y_nc1)sinΔθ+ΔX₁

＝(X_mnc-X_nc1)cosΔθ-(Y_mnc-Y_nc1)sinΔθ+X_pcb1+

X_e1 ···[1]

[ formula 3]

Y_m＝(X_mnc-X_nc1)sinΔθ+(Y_mnc-Y_nc1)cosθ+ΔY₁

＝(X_mnc-X_nc1)sinΔθ+(Y_mnc-Y_nc1)cosθ+Y_pcb1+Y_e1

···[2]

In contrast, when the actual mounting region reference mark 201 is assumed to exist at the position coordinate (X)_t，Y_t) When is, is

[ formula 4]

X_t＝(X_mnc-X_nc1)cosΔθ-(Y_mnc-Y_nc1)sinΔθ+X_pcb1

···[1]′

Y_t＝(X_mnc-X_nc1)sinΔθ+(Y_mnc-Y_nc1)cosθ+Y_pcb1

···[2]′

Here, the NC coordinates of the original corrected result must match the position coordinates of the actual mounting region reference mark ([1], [2 ]'). However, when the above formulas are compared, the results become

[ formula 5]

X_m-X_t＝X_e1≠0

Y_m-Y_t＝Y_e1≠0

The corrected NC coordinates do not match the actual position coordinates of the mounting area reference marks. The head 136 cannot be positioned on the position coordinates of the actual mounting area reference mark, and the positional coordinate displacement obtained from the recognition result obtained here becomes a correction value including a positioning error, and cannot be used for position correction.

As described above, the XY robot operation of the component mounting apparatus always includes a positioning error, and even if the correction value is measured with the glass substrate 200 as a reference, it does not constitute a true value and there is no absolute reference.

Therefore, in order to make the error zero as much as possible (in other words, to make the position coordinate data of the mounting area reference mark 201 match the data of the NC coordinates), the following process is performed on the obtained correction value.

In the actual component mounting operation of the component mounting apparatus, in order to correct the holding misalignment of the production substrate (to-be-mounted substrate) under the transfer table 165, the component mounting apparatus recognizes the reference marks of all the mounting regions as described above, and corrects each mounting position using the result. The results of the recognition of the two substrate reference position calculation marks 202-1 and 202-2 at this time are shown in FIG. 45. Here, the positional coordinate displacement obtained from the recognition results of the two substrate reference position calculation marks 202-1 and 202-2 includes a positioning error at the positions of the two substrate reference position calculation marks 202-1 and 202-2 in addition to the holding displacement.

When the component 62 is actually mounted on the mounting position 205 where the substrate 61 is to be mounted, the parallel misalignment, the inclination, and the expansion and contraction rate are obtained from the result of recognition of the substrate reference position calculating mark, and the mounting positions 205 are corrected and used. Specifically, all the mounting positions 205 are rearranged so that the displacement amount (holding displacement + positioning error) at the positions of the mounting region reference marks close to the two substrate reference position calculation marks 202-1 and 202-2 becomes zero (in other words, the position coordinate data of the two substrate reference position calculation marks 202-1 and 202-2 is matched with the NC coordinate data).

Specifically, as shown in fig. 46, the position of the mounting area reference mark as the correction value initial data is not zero because it is shifted in the X direction and the Y direction from the original position (the center position of the rectangular field of view area in fig. 47) as shown in fig. 47. In fig. 46, the vertical axis represents the amount of displacement, the horizontal axis represents the position in the X direction, the upper curve represents Δ X, i.e., the displacement in the X direction, and the lower curve represents Δ Y, i.e., the displacement in the Y direction.

Therefore, as shown in fig. 48 and 49, the correction values of the mounting region reference marks 201a and 201b in the vicinity of the two substrate reference position calculation marks 202-1 and 202-2 of the relatively small substrate 61S to be mounted are zero or substantially zero (for example, within a range of ± 5 μm) by performing coordinate conversion by rotating and moving the curve connecting the two mounting region reference marks 201a and 201b, and all the mounting positions are rearranged. In the graph of fig. 48, the mounting region reference marks 202-1 and 202-2 (on the diagonal line) are plotted on the same graph, but the data itself is measured at a constant Y coordinate and 10mm intervals in the X coordinate. Accordingly, the data shown as [202-2] on the graph is the data of the mounting region reference mark in which the Y coordinate data of the mounting region reference mark 202-1 is set to be the same and the X coordinate data is the same as the mounting region reference mark 202-2. This is also true in fig. 50.

Further, as shown in fig. 50 and 51, the correction values of the mounting area reference marks 201 in the vicinity of the two substrate reference position calculation marks 202-1 and 202-2 of the large-sized mounting substrate 61L are zero or substantially zero (for example, within a range of ± 5 μm) by performing coordinate conversion by rotating and moving the curve, and all the mounting positions are rearranged. Thus, the actual usage data of the correction value greatly differs depending on the mounting substrate.

Since there is no absolute reference in the process of determining the XY robot positioning error, the XY robot positioning error amount of each measured region coincides with the substrate to be mounted 61 at the time of production only with the positions of the two substrate reference position calculation marks 202-1 and 202-2 of the substrate to be mounted 61. Therefore, the correction values of the fiducial marks of the mounting region at the positions of the two substrate reference position calculating marks 202-1 and 202-2 close to the production substrate 61 are used to perform coordinate transformation so that the correction values at the two points are zero or substantially zero (for example, within a range of ± 5 μm), and then the alignment is performed. In this case, as in the case of the correction processing of the two reference substrate position calculating marks 202-1 and 202-2, the parallel misalignment, the inclination, and the expansion and contraction rate are determined, and all the mounting positions 205 are rearranged based on the results.

In fig. 52, the XY robot positioning error amounts of the mounting area reference marks 201a and 201b on the glass substrate 200 based on the substrate reference positions closest to the production substrate 61 are calculated by the markers 201-1 and 202-2, and the XY robot positioning error amounts of all the mounting area reference mark positions are coordinate-converted (coordinate-converted after considering the parallel misalignment, the inclination, and the expansion and contraction ratio) by the calculation unit 171 and stored in the storage unit 173.

The coordinate conversion is performed at the time of selecting a substrate type, and the offset values obtained by the conversion are added to the respective moving positions as correction values by the control device 170 at the time of each of the mark recognition operation, the component mounting operation, and the mounting offset measurement operation. By using the offset value in this manner, an error inherent to the robot can be grasped as a relative displacement between the positions.

Next, steps S8 to S12 in fig. 41 are steps for correcting the position, inclination, and shrinkage of the component mounting circuit board 61 during mounting. That is, the following steps are performed to correct the position, inclination, and shrinkage of the component mounting circuit board 61 at the time of mounting.

Specifically, in step S8 of fig. 41, the component-mounting circuit board 61 is held on the conveyance table 165 and positioned in the component mounting area.

Next, in step S9 of fig. 41, the at least two substrate reference position calculation marks 202-1 and 202-2 on the component mounting circuit substrate 61 held on the conveyance table 165 are recognized, respectively, and the position coordinates of the two recognized substrate reference position calculation marks 202-1 and 202-2 are obtained, respectively.

Then, in step S10 of fig. 41, the NC coordinates of the two substrate reference position calculation marks 202-1 and 202-2 are corrected based on the position coordinates of the two substrate reference position calculation marks 202-1 and 202-2 obtained. That is, the NC coordinates of the two substrate reference position calculation marks 202-1 and 202-2 are corrected to the position coordinates of the two substrate reference position calculation marks 202-1 and 202-2 based on the difference between the position coordinates of the two substrate reference position calculation marks 202-1 and 202-2 and the NC coordinates of the two substrate reference position calculation marks 202-1 and 202-2.

Next, in step S11 of fig. 41, when the component 62 held by the component holding head 136 is positioned above the component mounting position 205 of the component-mounting circuit board 61, the component mounting position 205 is corrected based on the offset value closest to the mounting region reference mark 201 (in other words, the offset value of the region including the mounting region reference mark 201 closest to the substrate recognition camera 140) of the substrate recognition camera 140 serving as an example of the recognition camera provided in the component holding head 136. Specifically, a nozzle (for example, a left end nozzle in fig. 35) 1361 constituting a reference among the plurality of nozzles 1361 of the head 136 is positioned on an NC coordinate of each mounting area reference mark 201 on the glass substrate 200 as an example of a reference substrate for mounting area reference mark recognition, an offset value of the mounting area reference mark 201 closest to the camera 140 is read from the storage unit 173 by the substrate recognition camera 140 fixed to the head 136, and the component mounting position 205 is corrected based on the offset value.

Next, in step S12 of fig. 41, the component 62 is mounted at the corrected component mounting position 205.

In the above description, the offset value is used in step S11, but the offset value may be added to the NC coordinate data of the substrate reference position calculating mark in step S9, and the substrate recognition camera may be moved to determine the position from the center of the field of view of the substrate recognition camera.

The above is an outline of the measurement of the correction value for obtaining the area offset value and the mounting position correction operation based on the measurement result.

Next, a more specific example of the component mounting method of embodiment 2 will be described with reference to fig. 54 to 56.

(1) First, for example, before the component mounting apparatus is shipped from a component mounting apparatus manufacturing plant to a user, the mounting region reference mark recognition operation is performed. After the transfer to the user, the following mounting region reference mark recognition operation is similarly performed in the case of overhaul or the like.

That is, as shown in fig. 54, in step S13A of fig. 54, the operator is prompted to select a mounting area reference mark recognition reference substrate type program for determining a correction value for each area offset value through the operation screen of the component mounting apparatus. The type and size of the glass substrate 200, which is an example of the mounting area reference mark recognition reference substrate, and the NC coordinate data of each position of the mounting area reference mark 201 on the glass substrate 200 are associated with the mounting area reference mark recognition reference substrate type program, and the glass substrate 200 is specified by selecting the substrate type, and the NC coordinate data of each position of the mounting area reference mark 201 on the glass substrate 200 is transmitted from the storage unit 173 to the control device 170.

As a more specific example, in the case of a 410mm × 240mm glass substrate, when 858 mounting region reference marks of 22 rows in the longitudinal direction × 39 columns in the transverse direction are arranged at intervals of 100mm in the longitudinal direction and the transverse direction, the coordinates of the 1 st mounting region reference mark are (10, 10), the coordinates of the 2 nd mounting region reference mark are (20, 10),...... and the coordinates of the 880 nd mounting region reference mark are (390, 220). In addition, as another specific example, in the case of a glass substrate of 510mm × 460mm, when 2156 mounting region reference marks of 44 rows in the vertical direction × 49 columns in the horizontal direction are arranged at intervals of 100mm in the vertical direction and the horizontal direction, the coordinates of the 1 st mounting region reference mark are (10, 10), the coordinates of the 2 nd mounting region reference mark are (20, 10),... and.. the coordinates of the 2156 th mounting region reference mark are (490, 440). These are examples of the data of the NC coordinates.

Subsequently, while or after the data of the NC coordinates is transmitted from the storage unit 173 to the control device 170, as step S13B in fig. 54, the glass substrate 200 in which the mounting region reference marks 201 are arranged in a grid pattern at equal intervals as shown in fig. 40 is positioned in the component mounting region by the transport stage 165 of the substrate transport device 190 (see step S1 in fig. 41).

After the glass substrate 200 is positioned in the component mounting area, as step S13C in fig. 54, the XY robot 120 is driven based on the NC coordinate data of each position of the mounting area reference mark 201 transmitted from the storage unit 173, the head 136 is moved, the substrate recognition camera 140 is moved to each position of the mounting area reference mark 201, all the mounting area reference marks 201 on the glass substrate 200 are recognized (see step S2 in fig. 41), and the positional coordinates obtained based on each recognition result of all the mounting area reference marks 201 are shifted (Δ X, Δ Y) or the positional coordinates including the shifted position (X + Δ X, Y + Δ Y) are stored in the storage unit 173 (see step S3 in fig. 41). In this case, the position coordinates of each mounting area reference mark 201 may be recognized and processed a plurality of times, and the position coordinates of each mounting area reference mark 201 may be acquired with higher accuracy.

The positions of the respective mounting region reference marks 201 are stored and managed in the storage part 173 as the respective moving positions of the component mounting head 136. Therefore, the control device 170 determines which area of the offset value is to be reflected by the positioning position of the component mounting head 136 based on the mounting area reference mark recognition operation, the component mounting operation, and the mounting offset value measurement operation (particularly, the mounting offset value measurement operation at the time of mounting the chip component or the QFP component) in the component mounting production, or any of these operations. Specifically, for example, an area surrounded by the 4-point mounting area reference marks 201 is assigned as one area, a position offset value of any one of the 4-point mounting area reference marks 201 is used as an area offset value for the mounting position of the component 62 mounted in the area, and the offset value is added to the position coordinates of the mounting position as an area offset value in the area to perform correction.

In the glass substrate of 410mm × 240mm of the above specific example, the positional coordinate displacement (-0.132, -0.051) or the positional coordinates (10-0.132, 10-0.051) including the displacement, which is obtained from the recognition result of the reference mark of the mounting region 1, is stored in the storage unit 173. Further, the positional coordinate displacement (-0.132, -0.051) or the positional coordinate (20-0.132, 10-0.051) including the displacement, which is obtained from the recognition result of the 2 nd mounting region reference mark, is stored in the storage unit 173. Further, the positional coordinate displacement (-0.139, -0.050) obtained from the recognition result of the 3 rd mounting region reference mark or the positional coordinate (20-0.139, 20-0.050) including the displacement is stored in the storage unit 173. Further, the positional coordinate displacement (-0.139, -0.049) obtained from the recognition result of the 4 th mounting region reference mark or the positional coordinate (10-0.139, 20-0.050) including the displacement is stored in the storage unit 173. The positional coordinate offset (-0.132, -0.051) of the fiducial mark of the 1 st mounting region is used as the region offset value. In another example, the positional coordinate displacement (-0.132, -0.051) or the positional coordinate (210-0.132, 93-0.051) including the displacement, which is obtained from the recognition result of the 51 st mounting region reference mark, is stored in the storage unit 173. Further, the positional coordinate displacement (-0.130, -0.067) obtained from the recognition result of the 52 th mounting region reference mark or the positional coordinate (220-0.130, 93-0.067) including the displacement is stored in the storage unit 173. Further, the positional coordinate displacement (-0.139, -0.050) obtained from the recognition result of the 53 th mounting region reference mark or the positional coordinate (220-0.139, 103-0.050) including the displacement is stored in the storage unit 173. Further, the positional coordinate displacement (-0.139, -0.049) obtained from the recognition result of the 54 th mounting region reference mark or the positional coordinate (210-0.139, 103-0.050) including the displacement is stored in the storage unit 173. The positional coordinate offset (-0.132, -0.051) of the 51 st mounting region reference mark is adopted as the region offset value. The same is done for the other mounting area fiducial markers.

(2) Next, production substrate variety selection is performed.

First, as shown in fig. 55, in step S21, the substrate type selection program is transferred from the storage unit 173 to the control device 170, and the operator is prompted to select the substrate type of the substrate 61 to be produced (mounted) through the operation screen of the component mounting device. When the operator selects a substrate type, the controller 170 reads NC coordinate data of the selected substrate size and the position coordinates of the mounting area reference mark 201 from the storage unit 173.

Next, in step S22, the control device 170 extracts the position coordinates of the two substrate reference position calculation marks 202-1 and 202-2 of the substrate 61 of the selected substrate type from the NC coordinate data read out from the selected substrate type.

In the above-described specific example of the glass substrate of 410mm × 240mm, (15, 18) and (215, 111) are extracted as the position coordinates of the substrate reference position calculation marks 202-1, 202-2.

Next, in step S23, the mounting region reference marks 201 on the glass substrate 200 closest to the positions of the two substrate reference position calculation marks 202-1 and 202-2 are extracted one by the calculation of the calculation unit 171 based on the data stored in the storage unit 173. For example, in fig. 52, the 1 st mounting region reference mark 201a on the lower left is extracted using the 1 st substrate reference position calculating mark 202-1, and the 2 nd mounting region reference mark 201b on the lower left is extracted using the 2 nd substrate reference position calculating mark 202-2.

In the glass substrate of 410mm × 240mm of the above specific example, the coordinate positions (10, 10) of the lower left 1 st mounting region reference mark 201a are extracted using the position coordinates (15, 18) of the 1 st substrate reference position calculating mark 202-1, and the position coordinates (210, 110) of the lower left 2 nd mounting region reference mark 201b are extracted using the position coordinates (215, 111) of the 2 nd substrate reference position calculating mark 202-2.

Next, in step S24, the average displacement, inclination, and expansion/contraction ratio are determined by the calculation of the calculation unit 171 based on the recognition results of the extracted two points of the 1 st mounting region reference mark 201a and the 52 nd mounting region reference mark 201 b.

Specifically, regarding the parallel misalignment, the 1 st mounting region reference mark 201a of the 1 st mounting region reference mark 201a and the 52 nd mounting region reference mark 201b at the two points described above is considered as a reference.

Thus, the offset value of the 1 st mounting area reference mark 201a is set to (Δ X)_a、ΔY_a) Then the amount of parallelism error (Δ X)_ab、ΔY_ab) Can be described by the following formula.

[ formula 6]

ΔX_ab＝ΔX_a

ΔY_ab＝ΔY_a

In the case of the glass substrate of 410mm × 240mm of the above specific example, if the region offset value of the 1 st mounting region reference mark 201a is (-0.132, -0.051), the parallel shift amount is (-0.132, -0.050) according to the above formula 6.

On the other hand, the inclination of the glass substrate 200 is an angle formed by a straight line connecting NC coordinates of the 1 st mounting region reference mark 201a and the 52 nd mounting region reference mark 201b and a straight line connecting coordinates obtained by adding respective offset values to the NC coordinates of the 1 st mounting region reference mark 201a and the 52 nd mounting region reference mark 201 b.

If the NC coordinates of the 1 st mounting area reference mark 201a and the 52 nd mounting area reference mark 201b are (X)_a、Y_a)、(X_b、Y_b) The offset values of the 1 st mounting area reference mark 201a and the 52 nd mounting area reference mark 201b are (Δ X)_a、ΔY_a) And (Δ X)_b、ΔY_b) The inclination Δ θ of the 1 st and 52 th mounting area reference marks 201a and 201b_abCan be described by the following formula.

[ formula 7]

Δθ_ab＝tan^-1{(Y_b-Y_a)/(X_b-X_a)}-tan^-1[{(Y_b

+ΔY_b)-(Y_a+ΔY_a)}/{(X_b+ΔX_b)-(X_a+ΔX_a)}]

In the above-described specific example of the glass substrate 410mm × 240mm, assuming that the NC coordinates of the 1 st mounting region reference mark 201a and the 52 nd mounting region reference mark 201b are (10, 10), (210, 110), the offset values of the 1 st mounting region reference mark 201a and the 52 nd mounting region reference mark 201b are respectively (10, 10), (210, 110)(-0.132, -0.051) and (-0.130, -0.067), the tilt Δ θ of the 1 st mounting area fiducial marker 201a and the 52 nd mounting area fiducial marker 201b_abBy the following formula 7

[ formula 8]

Δθ_ab＝tan^-1{(110-10)/(210-10)}-tan^-1[{(110-0.067)-(10-0.051)}/{(210-0.130)-(10-0.132)}]

＝-0.004125°

When the expansion/contraction ratio E of the glass substrate 200 is based on the glass substrate 200, the expansion/contraction ratio of the glass substrate 200 is 1.

Next, in step S25, the position coordinates of the positions of the mounting region reference marks 201 stored in step S3 of fig. 41 and corresponding to the entire region where the substrate 61 is to be mounted are calculated and corrected by the calculation unit 171 using the parallel misalignment and inclination (and the expansion/contraction ratio), and the position coordinates of the mounting region reference marks 201 after correction are stored in the storage unit 173. Specifically, the correction value of each mounting area reference mark 201 is corrected in consideration of the parallel displacement, inclination, and expansion/contraction ratio of the 1 st mounting area reference mark 201a and the 52 nd mounting area reference mark 201b, and then stored in the storage unit 173 as an offset value. Here, the parallel offset is (Δ X)_ab、ΔY_ab) Let the inclination be Δ θ_abLet the expansion/contraction ratio be E, and let the NC coordinates of the 1 st mounting region reference mark 201a be (X)_a、Y_a) The NC coordinate of the arbitrary mounting area reference mark 201 to be corrected is (X)_nc、Y_nc) The offset value is set to (Δ X)_R、ΔY_R) The corrected offset value (Δ X) of each mounting region reference mark 201_off、ΔY_off) Can be described by the following formula.

[ formula 9]

X_off＝E{((X_nc+ΔX_R)-X_a)}cosΔθ_ab-((Y_nc+ΔY_R)-Y_a)sinΔθ_ab}-(X_nc-X_a)+ΔX_ab

Y_off＝E{((X_nc+ΔX_R)-X_a)}sinΔθ_ab+((Y_nc+ΔY_R)-Y_a)cosΔθ_ab}-(Y_nc-Y_a)+ΔY_ab

In the case of the above-described 410mm × 240mm glass substrate of the above-described specific example, when the above-described parallel misalignment is (-0.132, -0.050), the tilt is set to Δ θ_abWhen the expansion and contraction rate is set to be E1.000026, the NC coordinate of the 1 st mounting region reference mark 201a is set to be (10, 10), and the offset value is set to be (-0.132, -0.050) at 0.004125 ℃, the corrected offset value (Δ X) of the 1 st mounting region reference mark 201_off、ΔY_off) Becomes (0, 0). Similarly, assuming that the NC coordinates of the mounting region reference mark 201 of 15 rows and 8 columns to be corrected are (150, 80) and the offset values are (-0.132, -0.060), the corrected offset value (Δ X) of the mounting region reference mark 201 is set to be the corrected offset value (Δ X)_off、ΔY_off) Becomes (-0.001, -0.015).

(3) Next, mounting area fiducial mark recognition and component mounting actions are performed.

First, as shown in fig. 56, in step S31, the control device 170 reads out the moving position to which the head 136 should move from the mounting data in the storage unit 173 in order to execute the mounting region reference mark recognition operation, the component mounting operation, or the mounting offset value measurement operation, and obtains the recognition position or the mounting position.

At this time, for example, during a component mounting operation, when the head 136 is moved by the XY robot 120 and the component 62 sucked and held by one of the nozzles 1361 of the head 136 is located at the mounting position of one of the components 62 of the substrate 61 after correction at one of the moving positions and becomes a mounting preparation state, the mounting region reference mark 201 of the head 136 which is closest to the center of the field of view of the substrate recognition camera 140 at this time is regarded as the mounting region reference mark 201 with respect to the component 62.

Similarly, in the mounting area reference mark recognition operation, the head 136 is moved by the XY robot 120, and when a certain nozzle 1361 of the head 136 is located at a position of a certain mounting area reference mark 201 after correction of the mounting area reference mark recognition reference substrate 200 at a certain moving position, the mounting area reference mark 201 closest to the center of the field of view of the substrate recognition camera 140 of the head 136 at that time is regarded as the mounting area reference mark 201 with respect to the certain mounting area reference mark 201.

Similarly, in the mounting offset value measuring operation, when the head 136 is moved by the XY robot 120 and at a certain moving position, when a certain nozzle 1361 of the head 136 is located at the position of a certain substrate reference position calculating mark 202-1 or 202-2 after correction of the mounting area reference mark recognition reference substrate 200, the mounting area reference mark 201 of the head 136 which is closest to the center of the field of view of the substrate recognition camera 140 at that time is considered as the mounting area reference mark 201 with respect to the substrate reference position calculating mark 202-1 or 202-2.

Next, in step S32, the offset value of the area corresponding to the movement position of the head 36 in step S31 is added to the position coordinates of the movement position of the head 136 by the arithmetic unit 171. Specifically, as shown in fig. 53, when there are M rows in the longitudinal direction of the substrate 61 to be mounted and N columns of mounting area reference marks 201 in the lateral direction (therefore, there are M × N mounting area reference marks 201 in total), a region (region indicated by P in fig. 53) surrounded by the 4-point mounting area reference marks 201 is assigned as one region. The correction is performed by using an offset value of the position of any of the 4-point mounting area reference marks 201, for example, the lower left mounting area reference mark 201c, as an area offset value with respect to the position coordinates of the mounting position of the component 62 mounted in the area (or the position coordinates of the individual mark constituting the mounting position target), and adding the offset value as an area offset value to the position coordinates of the mounting position (or the position coordinates of the individual mark constituting the mounting position target).

Then, by moving the head 136 to the corrected position coordinates, high-precision positioning can be ensured, and a high-precision mounting area reference mark recognition operation, a component mounting operation, or a mounting offset value measurement operation can be performed. In particular, in the component mounting operation, the area offset value can be used as a numerical value for correcting an individual mark corresponding to an individual component of an IC component (BGA component or the like) which requires high mounting accuracy (for example, the XY robot positioning accuracy is about ± 2 μm, and the overall accuracy as a mounting apparatus is about ± 20 μm).

In step S3 of fig. 41, when the position coordinates (position coordinates) of the recognized mounting region reference mark 201 are stored in the storage unit 173, the following correction may be added. That is, as shown in fig. 42, the position coordinates of the mounting area reference marks 201 are recognized at two points, i.e., the lower left and upper right, of the glass substrate 200, the parallel displacement and inclination of the glass substrate 200 with respect to the conveying table 165 are determined, and the calculation unit 171 calculates and calculates the recognized positions of all the mounting area reference marks 201 measured, taking into account the correction values.

Regarding the parallel displacement of the glass substrate 200, the mounting region reference mark 201A at two points of the mounting region reference marks 201A and 201B is considered as a reference. When the mounting region reference marks 201A and 201B are recognized, the center of the substrate recognition camera 140 is moved to the position of the mounting region reference mark 201 in the NC coordinates, and therefore the parallel displacement amounts (Δ X and Δ Y) become a displacement of the position coordinates (displacement amount from the center of the recognition field of view of the substrate recognition camera 140) obtained from the recognition result at the time of the mounting region reference mark recognition.

Thus, the positional coordinate displacement obtained from the recognition result of the mounting region reference mark 201A is (Δ X)_A、ΔY_A) (see FIG. 64), the amount of parallelism deviation (. DELTA.X) of the glass substrate 200_g、ΔY_g) Can be described by the following formula.

[ formula 10]

ΔX_g＝ΔX_A

ΔY_g＝ΔY_A

Further, the position coordinate system is transformed into an NC coordinate system.

The inclination of the glass substrate 200 is an angle Δ θ formed by a straight line connecting the mounting region reference mark 201A and the mounting region reference mark 201B on the NC coordinates and a straight line connecting the recognized mounting region reference mark 201A 'and the recognized mounting region reference mark 201B'.

That is, if the NC coordinates of the mounting area reference marks 201A and 201B are (X)_A、Y_A)、(X_B、Y_B) The positional coordinate displacement (displacement from the center of the field of view) obtained from the recognition result when recognizing the mounting region reference marks 201A and 201B is assumed to be (Δ X)_A、ΔY_A)、(ΔX_B、ΔY_B) Then the substrate is tilted by delta theta_gCan be described by the following formula.

[ formula 11]

Δθ_g＝tan^-1{(Y_B-Y_A)/(X_B-X_A)}-tan^-1[{(Y_B+(-ΔY_B))-(Y_A+(-ΔY_A))}/{(X_B+ΔX_B)-(X_A+ΔX_A)}]

＝tan^-1{(Y_B-Y_A)/(X_B-X_A)}-tan^-1[{(Y_B-ΔY_B)-(Y_A-ΔY_A)}/{(X_B+ΔX_B)-(X_A+ΔX_A)}]

Thus, the position coordinates of the recognized mounting region reference marks 201 are calculated by the calculation unit 171 in consideration of the parallel displacement and inclination of the glass substrate 200. Here, the parallel offset is (Δ X)_g、ΔY_g) An inclination of Δ θ_gThe NC coordinate of the mounting area reference mark 201A is (X)_A、Y_A) The NC coordinate of the mounting area reference mark N at an arbitrary position on the glass substrate 200 is (X)_N、Y_N) Mounting the recognition position (X) of the area reference mark N at an arbitrary position_RN、Y_RN) Is composed of

[ formula 12]

X_RN＝(X_n-X_A)cosθ-(Y_m-Y_A)sinθ+ΔX_g

Y_RN＝(X_n-X_A)sinθ+(Y_m-Y_A)cosθ+ΔY_g

Therefore, in step S3 of fig. 41, the recognition position of the mounting region reference mark N thus obtained may be stored in the storage unit 173 as the position coordinate (position coordinate) of the recognized mounting region reference mark 201.

According to the above-described embodiment 2, the mounting area reference marks 201 arranged at predetermined intervals on the glass substrate 200 as an example of the reference substrate for identifying the mounting area reference marks are identified, and the offset value for each area corresponding to the substrate size is determined as the area offset value based on the identification result, and the area offset value corresponding to each moving position of the component mounting head 136 is reflected as the correction value in the mounting position correction, the mark identification correction, and the mounting position offset value measurement operation or any of these operations, so that the misalignment factor due to the movement deformation of the XY robot is absorbed, and the optimum offset value corresponding to the substrate size is obtained, thereby performing the mounting with high accuracy.

In addition, when the mounting area reference mark is recognized, the offset value of the corresponding area of each moving position of the component mounting head 136 is reflected as a correction value, thereby absorbing the displacement factor caused by the motion deformation of the XY robot and obtaining the optimum offset value corresponding to the substrate size, thereby performing mounting with high accuracy.

The present invention is not limited to embodiment 2 described above, and may be implemented in various other modes.

For example, the two 1 st and 52 th mounting area reference marks 201A, 201B, 202-1, 202-2 may be any two different points other than the different positions of the mounting area reference mark recognition reference substrate or any diagonal of the mounting substrate to be mounted, or the different positions in any direction along the XY direction, in other words, the same point.

When the mounting region reference mark recognition reference substrate 200 is smaller than the mounting substrate 61, the mounting region reference mark recognition reference substrate 200 is positioned at either end of the component mounting region of the mounting substrate 61, and the position coordinates of the mounting region reference mark 201 are recognized and acquired, then the mounting region reference mark recognition reference substrate 200 is moved to either end of the component mounting region of the mounting substrate 61, the position coordinates of the mounting region reference mark 201 are recognized and acquired again, and the common portions are overlapped, and then the data is processed so that the position coordinates of the mounting region reference mark 201 are recognized and acquired in one large virtual mounting region reference mark recognition reference substrate 200. For example, as shown in fig. 57, the positional coordinate data [1] of the mounting area reference mark 201 measured at the normal position of the substrate and the positional coordinate data [2] of the mounting area reference mark 201 measured at the position shifted to the left by 350mm are combined. Only rotation and movement correction are performed so that the common portions of the data [1] and the data [2] coincide with each other. When the expansion/contraction ratio is added, the common portions do not match, and therefore the expansion/contraction ratio is not added.

(examples)

An example of the change in the amount of displacement and the change in the component mounting accuracy between the case where the offset value of each area in embodiment 2 is not applied and the case where the offset value is applied is shown.

The offset value of each region was measured using the reference mark 201 of the mounting region of the substrate of 428mm × 250mm shown in fig. 57.

In fig. 57, since the center of the field of view of the substrate recognition camera 140 is located 60mm from the center of the right-end nozzle 1361 in the X direction (i.e., the right direction in fig. 57) as the arrangement configuration of the head 136 during the recognition operation of the mounting region reference mark 201, the substrate recognition camera 140 needs to move 720.5mm (XL: substrate width 510mm +60mm + distance between both-end nozzles 150.5mm) in the X direction (i.e., the right direction in fig. 57) from the position of the substrate stopper which abuts the left end of the substrate 61 and positions the substrate 61 at the mounting position of the transfer table 165 in order to position all the nozzles 1361 from the left-end nozzle 1361 to the right-end nozzle 1361 over the entire region on the substrate 61.

However, when the mounting region reference mark recognition reference substrate used for recognizing the mounting region reference mark 201 is located only within a range of 410mm from the substrate stopper position in the X direction, the mounting region reference mark recognition reference substrate is displaced in the X direction, and the mounting region reference mark 201 is recognized again, whereby the entire region (0mm to 720.5mm) of the substrate 61 can be covered.

The graphs shown in fig. 58 and 59 plot output data of positional coordinate displacement obtained from the recognition result when the respective area offset values are used. The two curves in fig. 58 show the relationship between the X-direction position and the X-direction displacement amount when the head 136 is moved at a pitch of 10mm in the X direction, and the curve [1] is before the offset value of each area is used and the curve [2] is after the offset value of each area is used. The two curves in fig. 59 show the relationship between the Y-direction position and the Y-direction displacement amount when the head 136 is moved at a pitch of 10mm in the Y-direction, where the curve [1] is before the offset value of each area is used and the curve [2] is after the offset value of each area is used.

In the curve [1] before the offset value of each region in fig. 58 is used, the maximum error of 20 μm occurs at a position shifted by 220mm from the substrate stopper in the X direction before the offset value of each region is used, and an upward convex shape is formed. Instead, the corrected curve [2] varies substantially around zero.

As is clear from the graph of fig. 59, the graph [1] before the offset value of each area is used changes slightly obliquely in the Y direction, but the graph [2] after the offset value of each area is used changes almost in the vicinity of zero as in the X direction.

The curve [2] after using the offset values for the respective regions in fig. 58 and 59 is within ± 5 μm in both the X-direction and the Y-direction.

Next, with respect to the change in component mounting accuracy, fig. 60 shows mounting accuracy when the offset values of the respective regions of embodiment 2 are not used when a ceramic capacitor of a chip component of 1.6mm × 0.8mm as 400 dots is mounted on a substrate of 428mm × 250mm size, and fig. 61 shows mounting accuracy when the offset values of the respective regions of embodiment 2 are used. Fig. 62 shows mounting accuracy when the respective area offset values of embodiment 2 are not applied when a plurality of QFPs are mounted on a substrate, and fig. 63 shows mounting accuracy when the respective area offset values of embodiment 2 are applied. The dimension values in the figures are in mm scale.

As shown in fig. 61 and 63, the above results show that the mounting accuracy in the X direction and the Y direction tends to be improved. That is, it is found that the offset amount between the corrected device position data and the actual mounting position data is smaller in value than the case where the offset values of the respective areas according to embodiment 2 are not applied.

In addition, as an example of a specific numerical value, the correction value is about 10 to 30 micrometers. As an example of a small substrate, when coordinates are converted on a 428mm × 250mm substrate, the expansion/contraction ratio is 1.000025. As an example of a large substrate, when coordinates are converted on a 600mm × 250mm substrate, the expansion/contraction ratio is 1.00005. In addition, a small substrate of 100X 100mm or the like is also effective.

The present invention is applicable to mounting of electronic components, for example, small components such as square chip capacitors, square chip resistors, and transistors, or ICs to be mounted on fine chips such as QFPs and BGAs.

Instead of measuring the reference substrate for recognition of the mounting area reference mark by a camera, the displacement position of the substrate machine part may be measured by a laser length measuring device (in this case, the reference substrate for recognition of the mounting area reference mark is not necessary).

In addition to the correction based on the offset value, the accuracy can be further improved by reflecting the area offset value of the measurement position of the 'substrate camera offset value' and the 'inter-suction nozzle pitch' at the time of the camera correction to the mark recognition operation (substrate mark recognition, individual mark recognition corresponding to an IC component or the like, pattern mark recognition displayed on each substrate of the multi-chamfered substrate, group mark recognition displayed for each component group, difference mark recognition indicating defective display), the 'substrate camera offset value' and the 'inter-suction nozzle pitch' used for calculating the head movement position at each operation of the component mounting operation, the mounting offset value measurement operation, and the mounting area reference mark recognition.

In the above-described camera correction, the offset value of the substrate camera 140 and the inter-nozzle pitch (the distance between the nozzles of the plurality of nozzles) are obtained, but in the process of the obtaining, the correction value for correcting the deformation of the XY robot for each area is not reflected. Therefore, in the mark recognition, the component mounting operation, and/or the mounting offset value measurement operation, the offset value of the board camera 140 used in calculating the head movement position and the inter-nozzle pitch are reflected, and thus high-precision mounting can be performed. The offset value and inter-nozzle spacing of the substrate camera 140 is provided by the distance from the 1 st nozzle 1361-1. Therefore, in the mark recognition, component mounting operation, or mounting offset value measurement operation, when the offset value of the board camera 140 used in calculating the head movement position and the inter-nozzle pitch are reflected, the difference between the board camera offset value or the area offset value at the inter-nozzle pitch measurement and the area offset value at the position measurement of the 1 st nozzle 1361-1 is reflected at each operation.

Next, the relative relationship between the suction nozzle, the component recognition camera 150, and the substrate recognition camera during measurement will be described with reference to fig. 67A to 67C.

As shown in FIG. 67A, when the position of the 1 st nozzle (serving as a reference nozzle) 1361-1 is measured, the 1 st nozzle 1361-1 is positioned on the component recognition camera 150, and the position of the 1 st nozzle 1361-1 is measured. The position value of the 1 st nozzle 1361-1 obtained in this state measurement is set as an area offset value (X1, Y1).

Next, as shown in FIG. 67B, when the inter-nozzle distances of the nth nozzle 1361 to n are measured, the nth nozzle 1361 to n is positioned on the parts recognition camera 150, and the position of the nth nozzle 1361 to n is measured. The position values of the nth nozzle 1361 to n obtained in this state measurement are set as zone offset values (Xn, Yn). In the case of the head shown in fig. 67A to 67C, since the number of nozzles is 8 in total, 8 are measured in order from n being 2, and the area offset value of each 1 st nozzle 1361-1 is set.

Next, as shown in fig. 67C, when the substrate camera 140 is measured, the substrate camera 140 is positioned on the component recognition camera 150, and the position of the substrate camera 140 is measured. The position value of the substrate camera 140 obtained in this state measurement is set as the area offset value (Xp, Yp).

As shown in FIG. 68, the offset value of the substrate camera and the inter-nozzle spacing are provided by the distance from the 1 st nozzle 1361-1. Therefore, when reflecting the area offset value, the difference between the substrate camera offset value, the area offset value at the time of inter-nozzle pitch measurement, and the area offset value at the time of position measurement of the 1 st nozzle 1361-1 is reflected at the time of each operation.

For example, when the area offset value at the time of measuring the position of the 1 st nozzle 1361-1 at the time of camera calibration is (X1, Y1), the area offset value at the time of measuring the inter-nozzle pitch of the n-th nozzle 1361-n at the time of camera calibration is (Xn, Yn), and the area offset value at the time of measuring the substrate camera offset value at the time of camera calibration is (Xp, Yp), the area offset values reflected in the 'substrate camera offset value' at the time of the above-described operations become (Xp-X1, Yp-Y1), as described with reference to fig. 68. In addition, in the component mounting operation, the area offset value of the 'inter-nozzle pitch' reflected on the n-th nozzle 1361-n is (Xn-X1, Yn-Y1).

As shown in the flowchart of fig. 65, in the mounting area reference mark recognition operation, an area offset value corresponding to the position measurement position of the 1 st nozzle 1361-1 in the camera calibration is obtained in step S51.

Then, in step S52, an area offset value corresponding to the substrate camera offset value measurement position at the time of camera calibration is obtained.

Next, in step S53, when the area offset value is reflected in the board camera offset value, the movement position of the head 136 is determined, and in step S22 (fig. 45), the area offset value corresponding to the movement position of the head 136 is determined. Then, in step S23 (fig. 45), an area offset value corresponding to the position where the 1 st nozzle (the nozzle constituting the inter-nozzle pitch and the substrate camera offset value reference position) 1361-1 is located on the recognition camera is obtained, and in step S24 (fig. 45), an area offset value corresponding to the position where the substrate camera 140 is located on the recognition camera is obtained. In step S25, in the mounting region reference mark recognition operation, the region offset value obtained in step S22 is reflected, and in step S54, the difference between the region offset value obtained in step S23 and the region offset value obtained in step S24 (the region offset value obtained in step S24 — the region offset value obtained in step S23) is reflected. Specifically, in step S54, the difference between the area offset values obtained in step S52 and step S53 (the area offset value in step S53 — the area offset value in step S52) is added to the substrate camera offset value. Next, in step S55, the substrate mark recognition movement position is obtained using the substrate camera offset value in step S54. Next, in step S56, an area offset value corresponding to the movement position determined in step S55 is determined. Next, in step S57, the area offset value corresponding to the movement position determined in step S56 is added. Next, in step S58, the board camera is moved to the movement position determined in step S57.

With this configuration, the inter-nozzle pitch and the area offset value based on the XY robot motion distortion included in the board camera offset value can be reflected, and mounting with high accuracy can be performed.

Fig. 66 is a flowchart showing a procedure of performing a component mounting operation after reflecting an area offset value to a measurement position of the inter-nozzle pitch.

First, as described above, the area offset values of the 1 st nozzle and the nth nozzle at the time of camera calibration are obtained in steps S62 and S63. That is, in step S62, an area offset value of an area corresponding to the position measurement position of the 1 st nozzle at the time of camera calibration is obtained. Next, in step S63, an area offset value of an area corresponding to the distance between the nth suction nozzles at the time of camera calibration from the measurement position is obtained.

Next, in step S64, the difference between the zone offset values obtained in steps S62 and S63 (zone offset value in step S63 — zone offset value in step S62) is added to the nth inter-nozzle pitch.

Next, in step S65, the component mounting position is determined using the inter-nozzle pitch in step S64.

Next, in step S66, an area offset value corresponding to the movement position determined in step S65 is determined.

Next, in step S67, the area offset value of the area corresponding to the movement position determined in step S66 is added.

Next, in step S68, the nozzle is moved to the movement position determined in step S67.

In addition, by appropriately combining any of the above-described various embodiments, the effects each has can be achieved.

The component mounting method and apparatus of the present invention can be used to recognize the mounting area reference marks 201 arranged at every predetermined interval on the glass substrate 200, determine the offset value corresponding to each area of the substrate size as a correction value based on the recognition result, and reflect the corresponding offset value of each moving position of the component mounting head 136 as a correction value at the time of mounting position correction, mark recognition correction or mounting position offset value measurement, thereby improving the mounting accuracy.

According to the present invention, in a state where a reference substrate for mounting area reference mark recognition is held by the substrate holding device and positioned in a component mounting area, the position coordinates of mounting area reference marks arranged every predetermined interval on the reference substrate held by the substrate holding device are recognized, the position coordinates of the recognized respective mounting area reference marks are obtained, the difference between the NC coordinates of the respective mounting area reference marks and the position coordinates is obtained as a correction value, the NC coordinates of the position coordinates of at least two substrate reference position calculating marks of the circuit substrate for component mounting are obtained, the mounting areas adjacent to the two substrate reference position calculating marks are extracted from the recognized mounting area reference marks, and the position coordinates of the extracted mounting area reference marks are coordinate-converted, the correction values of the extracted mounting area reference marks are set to zero or substantially zero, and the offset values under the respective mounting area reference marks are obtained. Then, in a state where the component mounting circuit board is held by the board holding device in place of the mounting area reference mark recognition reference board and positioned in the component mounting area, the at least two board reference position calculation marks of the component mounting circuit board held by the board holding device are recognized, respectively, position coordinates of the recognized two board reference position calculation marks are obtained, respectively, the NC coordinates of the two board reference position calculation marks are corrected, respectively, based on the obtained position coordinates of the two board reference position calculation marks, and when the component held by the component holding head is positioned above the component mounting position of the component mounting circuit board, an offset value of the mounting area reference mark on the recognition camera provided in the component holding head is based on an offset value of the component mounting area reference mark closest to the recognition camera provided in the component holding head, after the position coordinates of the component mounting position are corrected, the component is mounted on the component mounting position based on the corrected position coordinates of the component mounting position. As a result, mounting area reference marks arranged at predetermined intervals on the mounting area reference mark recognition reference substrate are recognized, and a correction value of position coordinates for each area corresponding to the substrate size is determined as an offset value based on the recognition result, and the offset value corresponding to each moving position of the component mounting head is used in the mounting position correction, the mark recognition correction, and the mounting position offset value measurement operation or any of these operations, whereby the displacement factor due to the motion deformation of the XY robot is absorbed, the optimum offset value corresponding to the substrate size is obtained, and high-precision mounting (for example, mounting under the positioning precision condition of the level of ± 0.005mm in mounting) is performed.

In addition, when the mounting area reference mark is identified, the offset value corresponding to each moving position of the component mounting head is reflected as a correction value, so that the displacement factor caused by the motion deformation of the XY robot is absorbed, and the optimal offset value corresponding to the substrate size is obtained, thereby performing mounting with higher precision.

While the present invention has been fully described in connection with the preferred embodiments with reference to the accompanying drawings, various modifications and alterations will become apparent to those skilled in the art. It is to be understood that such changes or modifications are also encompassed within the scope of the present invention as set forth in the appended claims.

Claims

1. A component mounting apparatus is provided with an X-Y robot (120) having a component holding member (1361) for holding an electronic component (62) and mounting the electronic component held by moving in an X-axis direction (51) and a Y-axis direction (52) orthogonal to each other on a component mounting position of a circuit board (61), a fixed substrate recognition camera (140) and a component recognition camera (150) provided on the X-Y robot; a fixed substrate recognition camera (140) for shooting the substrate mark of the circuit substrate; a component recognition camera (150) for imaging the electronic component held by the component holding element, the component recognition camera comprising:

a camera reference mark (160) disposed proximate to the component recognition camera; and

and a control device (170) for correcting the component mounting position based on the position information of the camera reference mark obtained by the substrate recognition camera shooting the camera reference mark.

2. The component mounting apparatus according to claim 1, wherein:

a rack (110) for a component mounting device is also provided, wherein the rack is constructed in an integrated structure,

the X-Y robot comprises two identical Y-axis robots (121) arranged parallel to each other in the Y-axis direction and one X-axis robot (131) arranged in the X-axis direction orthogonal to the Y-axis robots, each Y-axis robot is directly formed on the component mounting apparatus stage, and has a Y-ball screw structure (122), the Y-ball screw structure (122) has one end (122a) as a fixed end and the other end (122b) as a support end, linearly thermally expands and contracts only in the Y-axis direction, and moves the X-axis robot in the Y-axis direction, and the X-Y robot linearly thermally expands and contracts in the X-axis direction and the Y-axis direction.

3. The component mounting apparatus according to claim 2,

the X-axis robot comprises:

an X-frame (132) having both ends fixed to the ball screw structures provided in the Y-axis robots; and

an X-ball screw structure (133) formed in the X-frame, having one end (133a) as a fixed end and the other end (133b) as a support end, and configured to be thermally extended and contracted linearly only in the X-axis direction, and to which a component mounting head (136) having the component holding member is attached and which is moved in the X-axis direction,

the X-Y robot having the X-axis robot is thermally extended and contracted linearly in the X-axis direction and the Y-axis direction.

4. The component mounting apparatus according to claim 3,

the X-frame has:

a support guide member (131) which is attached to the X-frame in the X-axis direction, slidably supports the component mounting head in the X-axis direction, and is made of a material different from the X-frame;

and a deformation preventing member (138) which is arranged opposite to the support and guide member and is fitted to the X-frame along the X-axis direction so as to prevent the X-frame from deforming, and which is made of the same material as the support and guide member.

5. The component mounting apparatus according to claim 4, wherein:

the component mounting head has a plurality of component holding components, and a drive source for holding components (1362) for moving the component holding components in a Z-axis direction (53) orthogonal to the X-axis direction and the Y-axis direction is provided independently for each component holding component, thereby reducing heat generation of the drive source for holding components.

6. A component mounting apparatus in accordance with any one of claims 1-5, wherein:

the camera reference mark is arranged at the same height position of the circuit substrate when the substrate recognition camera shoots the substrate mark in the circuit substrate in a Z-axis direction (53) which is orthogonal to the X-axis direction and the Y-axis direction.

7. A component mounting apparatus in accordance with any one of claims 1-5, wherein:

a plurality of the component recognition cameras are provided, and the camera reference mark is also provided in proximity to each component recognition camera.

8. The component mounting apparatus according to claim 1, wherein:

the X-Y robot is configured to linearly thermally contract in the X-axis direction and the Y-axis direction while keeping a relative position between the component holding member and the substrate recognition camera in a stationary state.

9. The component mounting apparatus according to claim 8, wherein:

and a rack (110) for a component mounting device, wherein the rack for the component mounting device is integrally formed by casting, and the X-Y robot generates the linear thermal expansion and contraction.

10. The component mounting apparatus according to claim 9, wherein:

the X-axis robot has an X-frame (132) having both ends fixed to the ball screw structures provided in the Y-axis robots, the X-frame having a support guide member (131) attached to the X-frame in the X-axis direction and a deformation preventing member (138) that holds the X-frame, is attached to the X-frame in the X-axis direction so as to oppose the support guide member, and prevents the X-frame from being deformed by heat, and the X-axis robot immobilizes the relative positions of the member holding member and the substrate recognition camera.

11. The component mounting apparatus according to claim 10, wherein:

the X-axis robot further comprises an X-ball screw structure (133), wherein the X-ball screw structure (133) is formed in the X-frame, one end (133a) is a fixed end, the other end (133b) is a support end, the X-ball screw structure is linearly thermally extended and contracted only in the X-axis direction, and a component mounting head (136) with the component holding component is mounted to move the component mounting head in the X-axis direction,

the component mounting head has a plurality of the component holding components, and a drive source (1362) for holding components for moving the component holding components in a Z-axis direction orthogonal to the X-axis direction and the Y-axis direction is independently provided on each of the component holding components, and the component mounting head sets the relative positions of the component holding components and the board recognition camera to a stationary state.

12. A component mounting method performed by a component mounting apparatus having a component holding member (1361) that holds an electronic component (62), mounts the electronic component held by moving in an X-axis direction (51) and a Y-axis direction (52) orthogonal to each other onto a component mounting position of a circuit substrate (61),

a substrate recognition camera (140) for photographing the substrate mark on the circuit substrate photographs a camera reference mark (160) arranged close to a component recognition camera (150) for photographing the electronic component held on the component holding member,

when the electronic component held on the component holding element is moved to a fixed component recognition camera (150) and photographed, the difference is used for correcting the moving amount,

13. The component mounting method according to claim 12, wherein:

when the mounting production is interrupted, the above-described photographing of the camera reference mark is performed just before the mounting production is started again.

14. The component mounting method according to claim 12 or 13, wherein:

and stopping the operation of the component mounting apparatus when the difference obtained by the photographing is equal to or greater than a set value.

15. A component mounting method according to any one of claims 12 to 13, wherein:

the positional relationship between the component holding device and the substrate recognition camera, the positional relationship between the component holding device and the component recognition camera, and the positional relationship between the substrate recognition camera and the component recognition camera are measured in advance, and these measurement values are processed as a correction premise of the component mounting apparatus.

16. A component mounting method according to any one of claims 12 to 13, wherein:

when a plurality of component recognition cameras are provided and a plurality of camera reference marks are provided, when the difference obtained by imaging one of the plurality of camera reference marks is less than a set value, imaging of the other camera reference marks is omitted.

17. A component mounting method according to claim 12, wherein the electronic component (62) held by the component holding member (1361) of the component holding head (136) movable relative to the substrate holding device is mounted at a component mounting position of the component-mounting circuit board (61) held by the substrate holding device (165),

recognizing the position coordinates of mounting area reference marks (201) arranged at predetermined intervals on the reference substrate held by the substrate holding device in a state where the mounting area reference mark recognition reference substrate (200) is held by the substrate holding device and positioned in the component mounting area, and determining the position coordinates of the recognized mounting area reference marks,

NC coordinates of position coordinates of at least two substrate reference position calculation marks (201A, 201B) of the component mounting circuit substrate are acquired,

and correcting the NC coordinates of the two substrate reference position calculation marks based on the position coordinates of the two substrate reference position calculation marks, respectively, and when the component held by the component holding head is positioned above each component mounting device of the circuit substrate, performing position coordinate correction of the component mounting position based on an offset value of the mounting area reference mark closest to a recognition camera provided in the component holding head, and then mounting the component on the component mounting position based on the position coordinates of the corrected component mounting position.

18. The component mounting method according to claim 17, wherein:

coordinate-converting the position coordinates of the extracted mounting area reference marks so that the correction values of the extracted mounting area reference marks close to the two substrate reference position calculating marks are zero or substantially zero, and determining offset values under the respective mounting area reference marks,

19. The component mounting method according to claim 17 or 18, wherein:

20. A component mounting apparatus according to claim 1, wherein said electronic component (62) is mounted on said component holding member (1361) of said component holding head (136) movable relative to said substrate holding apparatus by said X-Y robot, at a component mounting position of said component mounting circuit board (61) held on said substrate holding apparatus (165),

the substrate recognition camera (140) is arranged on the component holding head supported on the X-Y robot, and recognizes the position coordinates of the mounting area reference marks (201) arranged at every predetermined interval of the reference substrate held on the substrate holding device in the state that the reference substrate (200) for mounting area reference mark recognition is held on the substrate holding device and positioned in the component mounting area,

on the other hand, a calculation unit (171) is further provided for calculating the position coordinates of the mounting area reference marks from the recognition results of the mounting area reference marks recognized by the board recognition camera, and for calculating the difference between the NC coordinates of the mounting area reference marks and the position coordinates, as a correction value, and for extracting mounting area reference marks respectively close to the two board reference position calculation marks from the recognized mounting area reference marks based on the NC coordinates of the position coordinates of the at least two board reference position calculation marks of the component mounting circuit board, and for converting the position coordinates of the extracted mounting area reference marks into coordinates such that the correction value of the extracted mounting area reference marks is zero or substantially zero, and for calculating the offset value under each mounting area, at least two substrate reference position calculation marks for respectively identifying the component mounting circuit board held by the substrate holding device in a state where the component mounting circuit board is held by the substrate holding device in place of the mounting area reference mark identification reference board and positioned in the component mounting area, position coordinates of the two identified substrate reference position calculation marks are respectively obtained, and the NC coordinates of the two substrate reference position calculation marks are respectively corrected based on the obtained position coordinates of the two substrate reference position calculation marks,

the control device (170) performs correction of the position coordinates of the component mounting position based on an offset value of the mounting area reference mark closest to the recognition camera provided in the component holding head when the component held in the component holding head is positioned above the component mounting device of the component mounting circuit board, and then mounts the component to the component mounting position based on the corrected position coordinates of the component mounting position.

21. The component mounting apparatus according to claim 20, wherein:

the computing section coordinate-converts the position coordinates of the extracted mounting area reference marks to zero or substantially zero correction values of the extracted mounting area reference marks close to the two substrate reference position calculating marks, respectively, and obtains offset values under the respective mounting area reference marks.

22. A component mounting apparatus according to claim 20 or 21, wherein:

the computing section coordinate-converts the position coordinates of the extracted mounting area reference marks to zero or substantially zero correction values of the extracted mounting area reference marks adjacent to the two substrate reference position calculating marks, respectively, and obtains offset values under the respective mounting area reference marks.

23. A component mounting apparatus in accordance with any one of claims 20-21 wherein:

an XY robot (120) is provided, which has two Y-axis robots (121) arranged parallel to each other in a Y-axis direction (52), and an X-axis robot (131) that is arranged on the two Y-axis robots so as to be movable in an X-axis direction (51) orthogonal to the Y-axis direction, and that supports the component holding head (136) so as to be movable in the X-axis direction,

the two Y-axis robots and the one X-axis robot can move the component holding head in the XY-axis direction with respect to the substrate holding device.

24. The component mounting apparatus according to claim 23, wherein:

the component holding head (136) has a plurality of component nozzles (1361) which can respectively hold the components by suction and are arranged in the X-axis direction, and the substrate recognition camera is arranged on the component holding head (136) so that the imaging center of the substrate recognition camera (140) is positioned on the same axis as a straight line passing through the centers of the plurality of component nozzles.