JP2003234598A - Component-mounting method and component-mounting equipment - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a component-mounting method and component-mounting equipment which can mount a component accurately at a prescribed mounting position on a substrate, when an XY robot transferring the component travels in not an ideally rectilinear locus but, e.g. in a meandering locus, and enable mounting ultra micro-components with sufficient positional accuracy. <P>SOLUTION: A plurality of correction marks 63 are arranged rectilinearly along the moving axis direction of a moving means. A transferring head is moved in a moving axis (x) direction by the driving of the moving means. An image-recognizing part recognizes each of the correction marks 63 and obtains an amount Δs<SB>y</SB>of deviation of the correction mark positions from a straight line. On the basis of the amount Δs<SB>y</SB>of deviation obtained, the mounting position of the component which is recorded in a mounting program is corrected. <P>COPYRIGHT: (C)2003,JPO

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a component mounting method and a component mounting apparatus for mounting a component at a predetermined position on a board, and more particularly to a technique for minimizing mounting position displacement of the component.

[0002]

2. Description of the Related Art In recent years, in the field of electronic component mounting, a technique for mounting electronic components on a circuit board with high precision and at high speed is required in combination with miniaturization of electronic components and high density of mounting intervals. . Therefore, in the component mounting apparatus, by accurately processing the image data obtained by imaging the electronic component sucked and held by the suction nozzle of the transfer head, the suction posture of the electronic component to the suction head is accurately measured. Detecting, and also accurately detecting the fixed position shift etc. of the circuit board placed on the rail for board transfer, and based on these detection results, the mounting position of the electronic component is corrected and mounted. Position correction technology is generally widely adopted.

Specifically, as shown in FIG. 14, by driving each belt conveyor 83 incorporated in each of a pair of conveyor rails 81, a circuit whose both ends are supported on the conveyor surface of the belt conveyor 83. The substrate 1 is transported and stopped at a predetermined position. While fixing the circuit board 1 at this stop position, a suction nozzle 85 for sucking and holding electronic components is provided, and X
The component mounting process is performed by moving the transfer head 87 configured to be movable by the Y robot on the circuit board 1.
At this time, the fixed circuit board 1 is provided with board marks 67a and 67b for position detection on diagonal lines, and these board marks 67a and 67b are integrated with the transfer head 87 prior to the component mounting process. Recognition camera 8 provided
The image is picked up and recognized by 9 to detect the mark position. The deviation amount from the normal stop position of the circuit board 1 is calculated from the detected mark position, and the deviation amount is reflected in the component mounting position data to perform the mounting process.

According to such a mounting position correction process,
Depending on the amount of displacement of the suction position of the electronic component from the center of the suction nozzle 85 and the amount of displacement of the fixed position of the circuit board 1 on the side of the transport rail 81, the component mounting position is set to a preset regular position. By correcting the data, the required mounting position accuracy can be obtained.

[0005]

However, even if the above-described mounting position correction processing is performed, it may not be possible to eliminate the occurrence of the component mounting position deviation. That is, each axis of the XY robot that moves the transfer head 87 is connected to the transport rail 81.
When the parallelism and the verticality with respect to the XY robot are deviated, or when the movement path of each axis of the XY robot is not a linear motion but meanders, the XY robot and the transfer rail 81
Even if the deviations of the two are corrected based on the deviation amount of one representative point, the deviation amounts of the other points are different, and therefore the positional deviations of the both are not corrected as a whole. Therefore, in the above case, the circuit board 1 on the side of the transport rail 81
Since the electronic components held on the transfer head 87 side cannot be coordinated with each other for coordinate management, the electronic components cannot be accurately mounted at a predetermined position on the circuit board 1.

For example, as shown in FIG. 15, in comparison with an ideal straight line locus L _{a on which} the X-axis of an XY robot should originally move, a meandering locus L _b swings in the y direction as shown in FIG. Considering the cases that occur, the linear locus L _a and the meandering locus L _b
, And x are in agreement at the position of x _a corresponding to one of the substrate marks 67a, there is no problem for this position of x _a , but x _b corresponding to the other substrate mark 67b.
At the position of, the meandering locus L _b deviates from the linear locus La by δ in the y direction. Therefore, when the board mark 67b is recognized, it is determined that the board mark 67b is present at a position shifted by δ, and the correction amount of the board fixing position set by the board mark 67a and the board mark 67b becomes
The correction amount is different from the actual one. When components are mounted on the basis of this correction amount, a mounting position deviation naturally occurs.

[0007] Among the deviation from a straight line path L _a of the XY robot, for due to the deviation of parallelism, perpendicularity of the axis, or to improve the assembling accuracy of the XY robot to the component mounting apparatus, the appropriate Although it can be corrected to some extent by the calibration process, in particular, the deviation such that the moving path draws a meandering locus L _b is caused by a minute dimensional error of each constituent member of the XY robot, a slight assembly error or the like. , Are generated as a result of superposition of each factor. This shift amount is generally a small amount, but in the recent high-density mounting of extremely small size chip parts, for example, 0603 chip parts, this small amount of fluctuation cannot be ignored.

The present invention has been made in view of such a situation, and even if the XY robot for transferring parts does not follow an ideal linear trajectory but operates, for example, a meandering trajectory. Provided are a component mounting method and a component mounting apparatus capable of accurately mounting a component at a predetermined mounting position on a board, and therefore, it is possible to mount a component of extremely small size with sufficient positional accuracy. With the goal.

[0009]

In order to achieve the above object, a component mounting method according to a first aspect of the present invention is provided with a component holding portion for detachably holding a component and an image recognition portion having an image pickup camera. And a moving means for moving the transfer head with respect to a substrate, which is arranged facing the transfer head and is a mounting destination of the held component, and records the mounting position of the component. A component mounting method for moving the transfer head in parallel to the substrate surface according to the implemented mounting program to mount the component held by the component holder at a predetermined position on the substrate, the moving means comprising: While a plurality of correction marks are linearly arranged along the moving axis direction of the, the transfer head is moved in the moving axis direction by the driving of the moving means and the correction marks are respectively set by the image recognition unit. Identify, and determine the amount of deviation from the straight line of the correction mark position, and correcting the mounting position of the component which is recorded on the mounting program based on the obtained amount of deviation.

In this component mounting method, when the mounting means is driven by driving the moving means which operates in a coordinate system different from the coordinate system in which the position of the board is managed, a meandering locus is generated in the movement movement of the axis by the moving means. Even if it occurs, by measuring this meandering trajectory in advance and performing feedback correction to the mounting position data of the mounting program, it becomes possible to stably mount the component at an accurate position where the positional deviation due to the meandering motion is corrected. As a result, it is possible to stably carry out the mounting operation with a narrow pitch even for an extremely small component such as a 0603 chip component with sufficient positional accuracy.

According to a second aspect of the present invention, there is provided a component mounting method, wherein the moving means has two moving axes which are orthogonal to each other, and the correction marks arranged along the respective moving axis directions are respectively recognized, and the component is mounted. The mounting position of is corrected with respect to each of the moving axis directions.

In this component mounting method, even if the moving means moves on a two-dimensional plane having two orthogonal moving axes, the parallelism, the verticality, and the meandering movement are corrected with respect to the respective axes. As a result, the mounting can be performed with high accuracy even at an arbitrary position on the plane.

According to a third aspect of the present invention, there is provided a component mounting method, wherein the recognized discrete correction mark positions are interpolated to generate continuous position data, and the component mounting positions are based on the continuous position data. Is corrected.

In this component mounting method, the discrete correction marks are recognized and the movement path of the moving means is obtained as continuous position data, so that the required number of correction marks can be maintained while maintaining the required position accuracy. Therefore, the correction process can be simplified.

According to a fourth aspect of the present invention, in the component mounting method, the correction of the mounting position is added to the displacement amount obtained by the correction mark, and the displacement amount of the substrate from the regular position for mounting the substrate, It is characterized in that at least one of the deviation amounts of the component from the regular component holding position of the component holding portion is adjusted.

In this component mounting method, in addition to the shift amount of the axial movement obtained from the correction mark, at least one of the positional shift of the substrate and the shift from the holding position of the component is corrected to correct the component mounting. The total amount of deviation that occurs is collectively corrected, and high-precision component mounting becomes possible.

According to another aspect of the component mounting apparatus of the present invention, there is provided a transfer head on which a component holding unit for holding the component detachably and an image recognition unit having an image pickup camera are mounted, and the transfer head is disposed so as to face the transfer head. A moving unit that moves the transfer head with respect to a substrate on which the held component is mounted,
A component mounting apparatus that mounts a component at a predetermined position on a board according to a mounting program in which the mounting position is recorded, and is provided along a moving axis direction of the moving means at or near a board fixing portion that fixes the board. A plurality of correction marks and the moving means are driven to move the transfer head in the movement axis direction, the image recognition unit recognizes each of the correction marks, and the correction mark positions from the straight line are detected. A controller is provided, which calculates a shift amount and corrects the mounting position of the component recorded in the mounting program based on the obtained shift amount.

In this component mounting apparatus, when the moving means operating in a coordinate system different from the coordinate system in which the position of the board is managed is driven to perform the mounting operation, a meandering locus is generated in the movement movement of the axis by the moving means. Even if it occurs, the controller can measure this meandering trajectory in advance and perform feedback correction to the mounting position data of the mounting program, so that the component can be stably mounted at an accurate position in which the positional deviation due to the meandering motion is corrected. It will be possible. As a result, it is possible to stably carry out the mounting operation with a narrow pitch even for an extremely small component such as a 0603 chip component with sufficient positional accuracy.

According to a sixth aspect of the component mounting apparatus, the moving means has two moving axes which are orthogonal to each other, and the control section obtains the deviation amount with respect to each moving axis to correct the mounting position. It is characterized by doing.

In this component mounting apparatus, even if the moving means moves on a two-dimensional plane having two orthogonal moving axes, the parallelism, the verticality, and the meandering motion are corrected with respect to the respective axes. As a result, the mounting can be performed with high accuracy even at an arbitrary position on the plane.

[0021]

BEST MODE FOR CARRYING OUT THE INVENTION Preferred embodiments of a component mounting method and a component mounting apparatus according to the present invention will be described in detail below with reference to the drawings. FIG. 1 is a schematic overall perspective view of a component mounting apparatus according to an embodiment of the present invention, FIG. 2 is a partially enlarged perspective view of the configuration of a mounting head of the component mounting apparatus, and FIG. 3 is a main part of the component mounting apparatus. The block block diagram which shows is shown. At the center of the upper surface of the base 11 of the component mounting apparatus 100 in the depth direction, the loader unit 13 for loading the circuit board 1 along the x direction.
The unloader section 15 for unloading the circuit board 1 along the x direction is provided at the center in the depth direction opposite to the loader section 13. The loader unit 13 and the unloader unit 15 each have a pair of guide rails 17 for carrying the substrate.

The loader unit 13 and the unloader unit 15
On the upper surface of the base 11 between the and XY, the XY serving as a board fixing section that receives the circuit board 1 loaded from the loader section 13 and unloads the circuit board 1 to the unloader section 15 and is movable in the XY directions. A table 21 is provided. The XY table 21 has a pair of support rails 19, and the circuit board 1 is fixed between the support rails 19.

At both ends of the upper surface of the base 11 in the x direction, Y
The axis robots 23 and 24 are provided along the y-direction, respectively, and the X-axis robot 25 spans the Y-axis robots 23 and 24.
Are suspended horizontally in the y direction. X
The axis robot 25 is provided with a transfer head 27 so as to move and position in the xy direction within the mounting work area. The X-axis robot 25 and the Y-axis robots 23 and 24 constitute an XY robot 29 as a moving unit that moves in the x-direction and the y-direction by a driving mechanism such as a combination of a ball screw and a nut and a driving belt. . The transfer head 27 is provided with a plurality of replaceable suction nozzles 31 as suction means for sucking and holding components, and also for picking up and recognizing board marks, NG board marks, and the like on the circuit board 1. A board recognition camera 33 as an image recognition unit is also provided.

A plurality of parts cassettes 35, which are component supply devices for sequentially supplying components mounted on the circuit board 1 to predetermined component supply positions, are attached to and detached from the upper end of the base 11 in the y direction. Component supply section 37 that can be mounted
Is provided. Although not shown, the component supply unit 37 is mainly a large component (for example, BGA: Ba).
ll Grid Allay and QFP: Quad Flat Package ICs, connectors, etc.) are also provided to supply parts trays. Further, the component supply unit 37 in the component mounting work area
A nozzle station 39 for accommodating a plurality of types of suction nozzles 31 and for replacing the suction nozzles 31 as needed is provided in the vicinity of. Further, in the vicinity of the component supply unit 37, a component recognition device 41 for recognizing the suction posture and the like of the component by picking up an image of the component sucked by the suction nozzle 31 of the transfer head 27 with a recognition camera is provided.

As shown in FIG. 2, a plurality of mounting heads 43 to which the suction nozzles 31 are attached (4 in the illustrated example).
Individual mounting heads 43a, 43b, 43c, 43d: component holding means) are connected side by side to form a multiple head. Each mounting head 43a, 43b, 43c, 4
3d has the same structure, and has a suction nozzle 31 and an actuator 45 for causing the suction nozzle 31 to move up and down.
And a motor 4 for causing the suction nozzle 31 to perform θ rotation.
7, a timing belt 49, and a pulley 51. The suction nozzle 31 of each mounting head is replaceable,
The other suction nozzles are previously housed in the nozzle station 39 on the base 11 of the component mounting apparatus 100. The suction nozzle 31 is, for example, an S size nozzle that sucks a minute chip component of about 1.0 × 0.5 mm, a 18 mm square QFP.
There is an M size nozzle or the like for adsorbing, and is selected and used according to the type of electronic component to be mounted.

Further, inside the component mounting apparatus 100, a control section 53 for identifying and controlling each parts cassette 35 and the like.
(See FIG. 3), a display means 55 such as a monitor and a warning lamp such as a liquid crystal panel and a CRT, and an input means 57 such as a touch panel and a keyboard are provided on the front surface of the component mounting apparatus 100. Also, the input means 57
There may be a bar code reading device for inputting the parts information of the parts cassette 35. The control unit 53 is connected to the XY table 21, the XY robot 29, the transfer head 27, the component recognition device 41, and the like, and the storage unit 59, and controls these devices.

The storage unit 59 stores a mounting program such as which components are mounted in what positions in what order, and which component supply unit 37 (parts cassette 35) at which position.
Etc.), array information such as array information, array information of the arrayed components, nozzle program such as which nozzle is to be located in which nozzle station 39, nozzle information disposed in the nozzle station 39, shape of each component, A parts library of parts information related to height, etc., a supply library of parts tray information related to the shape and height of each parts tray, board information related to the shape of each board, etc., as well as shapes of suction nozzles and rails for carrying each board. Information such as the substrate transfer position is stored.

Next, the operation of the component mounting apparatus 100 having the above configuration will be described. When the circuit board 12 carried in from the loader unit 13 having the guide rail 17 shown in FIG. 1 is conveyed to a predetermined mounting operation position 61, the transfer head 27 is moved in the XY plane by the XY robot 29, and the parts are moved. Cassette 3
A desired electronic component is sucked by the suction nozzle 31 of the mounting head 43 from the component supply unit 37 such as 5 based on the mounting program, and is moved onto the recognition camera of the component recognition device 41. The component recognition device 41 recognizes the suction posture of the electronic component based on the picked-up image and the component library data, and performs a correction operation according to the suction posture. As this correction operation,
The displacement amount in the X direction and the Y direction is given to the XY robot 29 as an offset, and the displacement amount of the rotation component is performed by rotating the suction nozzle 31 by the motor 47. After that, the electronic component sucked at a predetermined position on the circuit board 1 is mounted.

Each mounting head 43a, 43b, 43
The suction nozzles 3c, 43d, ... When sucking an electronic component from the parts cassette 35 or the like by the suction nozzle 31 and mounting the electronic component at a predetermined position on the circuit board 1.
1 is moved down from the XY plane in the vertical direction (Z direction).
In addition, the mounting operation is performed by exchanging the suction nozzle 31 mounted on the mounting head 43 with an appropriate one from the nozzle station 39 according to the type of electronic component. By repeating the suction of the electronic component and the mounting operation on the circuit board 1, the mounting of the electronic component on the circuit board 1 is completed. The circuit board 1 on which the mounting is completed is carried out from the mounting operation position 61 to the unloader section 15, while a new circuit board is carried into the loader section 13, and the above-described operation is repeated.

By the way, the component mounting apparatus 100 having the above configuration
Then, as conceptually showing the coordinate system of the apparatus in FIG. 4, a reference coordinate system (xy coordinate system) which is a moving plane of the XY table 21 on the base 11, and a transfer head 27 by the XY robot 29. And a robot coordinate system (XY coordinate system) that is a moving plane of the robot. Since the mounting position data of the component of the mounting program is data for controlling the XY robot 29, it is the XY robot coordinate system, and the actual mounting position of the component mounted according to this mounting program is expressed in the reference coordinate system. become. If these two coordinate systems have accurate parallelism and perpendicularity, accurate coordinate management can be performed between them, but both axes may be displaced from each other,
If the movement of the shaft itself has a meandering component, accurate position control cannot be performed.

Therefore, the component mounting apparatus 100 according to the present invention.
In the above, in the XY table 21 of the reference coordinate system, a plurality of correction marks are provided on a straight line parallel to the axis of the reference coordinate system in the moving axis direction of the XY robot 29, and these correction marks are provided before the mounting operation of the robot. XY driven by coordinate system
The robot 29 takes an image while moving the transfer head 27 to detect the mark position, thereby detecting the deviation from the straight line, that is, the deviation amount of the axes of both coordinate systems, and detecting the deviation amount. The deviation of the coordinate system is corrected by feeding back to the component mounting position data.

A specific example of performing feedback correction between the reference coordinate system and the robot coordinate system will be described below.
FIG. 5 shows an XY provided with correction marks according to the present embodiment.
It is a top view which shows a table. The circuit board 1 is fixed by suspending its both ends on a conveyor belt 65 provided on a pair of support rails 19 of the XY table 21. On one of the support rails 19 of the XY table 21,
The correction marks 63 are provided at a predetermined fixed interval L over the entire rail length.
Is provided. The correction marks 63 are arranged on a straight line with high accuracy, and have a contrast so that the marks can be easily recognized by the image data obtained by imaging so that the correction marks 63 can be easily separated from the support rail 19 serving as an image background. It is set by using an appropriate means such as a fine shape so that the center position of the mark (or the position of the characteristic point) can be easily detected with high accuracy. Here, as an example, a mark in which a black dot is drawn at the center of a white circle is used, and the mark position is detected by obtaining the position of the black dot in the white background.

The arrangement interval L of the correction marks 63 is appropriately set to an interval at which the time required to detect the correction marks and the required correction accuracy intersect with each other. At the time of detection, the mark detection time may be shortened by detecting while thinning out a predetermined number. The support rail 19 provided with the correction mark 63 is preferably a fixed support rail that does not move regardless of the substrate size, rather than a support rail that moves in the y direction depending on the substrate size. Also,
It may be provided on an existing fixing member near the support rail 19.

Now, a procedure for mounting a component by correcting the deviation between the reference coordinate system and the robot coordinate system by using the XY table provided with the correction marks will be described. FIG. 6 is a flowchart illustrating a procedure of mounting the component while correcting the component mounting position by detecting the correction mark according to the present embodiment.

The following is a sequential description based on this flowchart. First, the XY table 21 receives the circuit board 1 from the loader unit 13 of the component mounting apparatus 100, and fixes the circuit board 1 at a predetermined mounting operation position 61. In this state,
The XY robot 29 is operated to recognize the board mark of the circuit board 1 by the board recognition camera 33 mounted on the transfer head 27 (step 1, hereinafter abbreviated as S1).
Then, the recognition data of the recognized board mark is transferred to the control unit 53.
(S2).

FIG. 7 shows the correction amount by the substrate mark.
It is a figure. The circuit board 1 is fixed by shifting from the ideal position.
If it is turned on, the actual position of the circuit board 1 is in the x, y directions and
It has a shift component in the rolling direction. This shift component is
By capturing the positions of the marks 67 and 67 and detecting the position of each mark
Geometrically determined. That is, the detected board mark position
Equivalent to the coordinates of the midpoint of the connecting line segment (black circle in the figure) and this midpoint
The coordinates of the midpoint (white circle in the figure) at the ideal circuit board position
By calculating the_km, Δy_kmWanted
Rotation component θ_kmIs also required. These deviations Δ
x_km, Δy_km, And rotation component θ_kmOf the circuit board 1
The shift component can be quantitatively derived over the entire surface. That is, times
Amount of deviation in the x and y directions due to the rotation component of the road substrate 1.
R_x(X_i, Y_i, Θ_km), R_y(X_i, Y_i, Θ_km)
Then, the deviation correction amount Δx of the circuit board 1 _ki, Δy_kiIs
It is obtained by the equation (1).

Δx _ki = R _x (x _i , y _i , θ _km ) + Δx _km Δy _ki = R _y (x _i , y _i , θ _km ) + Δy _km (1) In the control unit 53, the coordinates x _i , y The relationship between the deviation correction amounts Δx _ki and Δy _ki of the circuit board 1 according to the above equation (1) with respect to _i is set. Here, the above i represents the number of component data of the mounting program and is an integer from 1 to N.

Next, in order to recognize the correction mark 63 on the support rail 19 of the XY table 21 shown in FIG.
Only the X-axis robot 25 of the XY robot 29 is operated to move the transfer head 27 in the x direction, and the substrate recognition camera 33 mounted on the transfer head 27 sequentially corrects the correction marks 63.
Image. As a result, each correction mark is recognized to obtain the mark position (S3), and the y coordinate value (and the x coordinate value, if necessary) of each recognized correction mark is transmitted to the control unit 53 as recognition data (S4). This recognition operation is corrected by the correction mark 6
It is repeated for the number n of 3 (S5).

Here, since the correction marks 63 are provided discretely, as shown in FIG. 8 showing a state of interpolation processing of each correction mark position, continuous coordinate data is made to correspond to an arbitrary mounting position. It is preferable to obtain. An interpolation method using a spline function or the like can be preferably used for the interpolation processing. The reason why the correction marks 63 are provided at predetermined constant intervals as described above is also to reduce the calculation amount of this interpolation processing.

By this interpolation processing, the control section 53 sets the interpolation curve y = S (x) obtained from the positions x _mj and y _mj (j = 1 to n) of the respective correction marks.

Next, the transfer head 27 is mounted on the component mounting apparatus 10.
It moves to the component supply unit 37 of 0 and sucks a predetermined electronic component to the suction nozzle 31 of the mounting head 43 (S6). Then, the transfer head 27 moves onto the component recognition device 41 in a state where the electronic component is sucked and held, and images the electronic component sucked by the suction nozzle 31. From this imaged image, the presence or absence of a suction error of the electronic component and the suction posture (suction position shift, rotation component, etc.) with respect to the suction nozzle 31 are recognized (S7). The component recognition data obtained at this time is transmitted to the control unit 53 (S8).

FIG. 9 is an explanatory view showing the shift amount of the component sucked by the suction nozzle. As shown in FIG. 9A, when the electronic component 3 is sucked by the suction nozzle 31, the shift amounts Δx _sp and Δy _sp between the suction nozzle center and the component center and the rotation component θ _n are obtained, and further, FIG. As shown in (b), when the rotational component is corrected by driving the motor 47 (see FIG. 2) (corrected to θ _n = 0), the deviation amounts Δx _s and Δy with respect to the electronic components in the x direction and the y direction. Calculate _s by calculation.

Next, the board mark recognition data obtained above,
Using the correction mark recognition data and the component recognition data, the mounting position of the electronic component specified by the mounting program on the circuit board 1 is calculated (S9). That is, the mounting position data of a total of N electronic components specified in the mounting program is x
_pi, When a y _pi (i is an integer of up to 1 to N), a mounting position in the robot coordinate system of the corrected can be expressed by equation (2).

X _i = x _pi + Δx _ki + Δx _si + x _ofs Y _i = y _pi + Δy _ki + S (y _pi ) + Δy _si + y _ofs (2)

Here, x _ofs and y _ofs are _stored in the XY table 21 as offset values between the origin of the robot coordinate system (X, Y) mechanically set and the origin of the reference coordinate system (x, y). It is the sum of the offset values of the fixed origin position of the circuit board 1 and the origin of the reference coordinate system (x, y). As a result, the mounting position of the electronic component expressed in the reference coordinate system is uniquely expressed in the robot coordinate system.
Then, the electronic component sucked and held by the suction nozzle 31 of the transfer head 27 is moved to a predetermined mounting position by driving the XY robot 29 (S10), and the electronic component is placed on the circuit board 1.
It is mounted on top (S11). The above-described operations from S6 are repeated until the final step of the mounting program to mount electronic components (S12). As a result, the electronic component can be accurately aligned and mounted on the circuit board 1.

FIG. 10 shows the component mounting with the above correction.
It is explanatory drawing which shows notionally how to perform. XY robot now
The X-axis robot 25 of the unit 29 has a reference coordinate system (x, y)
When it has a characteristic that it moves meandering with respect to the coordinate axes of
Think The transfer head 27 is moved to the x-axis by the X-axis robot 25.
When moved in the x direction above, the transfer head 27 moves to L _rx
The trajectory of the meandering curve shown by is drawn. This meandering characteristic
Moves the transfer head 27 to the XY table by the X-axis robot 25.
Support rail on the side where the correction mark 63 of the bull 21 is provided
19 and move each image of the correction mark 63
And recognize each mark and connect each mark position by interpolation.
And with L_sxIs required as. This meandering characteristic is the X-axis robot
The Y-axis robots 23 and 24 are
This characteristic does not change even if you move to the y-coordinate position.
Yes. That is, the meandering locus L_rxIs the meandering locus L_sxSame amplitude as
The locus has a phase.

For example, the meandering locus L _{rx at} the position of x _c
Indicates that a deviation amount of Δs _y is generated in the y direction, and the electronic component mounted at the position x _c (marked by ◇ in the figure) is the position corrected by this deviation amount of Δs _y (marked by ◆ in the figure). ) Is set to the mounting target position, the electronic components are consequently mounted on the circuit board 1 at correct positions. In this example, only the correction of the positional deviation due to the meandering characteristic of the X-axis robot 25 is referred, but as described above, the positional deviation is also corrected by the board mark recognition data and the component recognition data. And

According to the present embodiment, when the mounting operation is performed by driving the members in a coordinate system (robot coordinate system) different from the coordinate system (reference coordinate system) in which the position of the circuit board 1 is managed, Even if the parallelism and perpendicularity of both coordinate systems do not exactly match, this is corrected and the circuit board 1 of the electronic component is corrected.
It is possible to maintain the mounting position on the board with high accuracy. Even if a meandering locus occurs in the movement of the axis, the meandering locus is measured in advance and fed back to the mounting coordinate data, so that the component is stably mounted at the correct position with the positional deviation due to the meandering motion corrected. It becomes possible to do. As a result, it is possible to stably carry out the mounting operation with a narrow pitch even for an extremely small component such as a 0603 chip component with sufficient positional accuracy.

Next, a second embodiment of the component mounting method and component mounting apparatus according to the present invention will be described. FIG. 11 is a plan view showing an XY table provided with correction marks according to the present embodiment. Here, members having the same functions as those of the configuration of the first embodiment described above are given the same reference numerals, and the description thereof will be omitted. In this embodiment, in addition to providing the correction mark 63 on the support rail of the XY table 21 along the x direction, a plurality of correction marks 64 are also provided in the y direction. In the following description, the correction mark 63 will be described as a y-direction correction mark, and the correction mark 64 will be described as an x-direction correction mark.

The y-direction correction mark 63 is the XY table 21.
The x-direction correction mark 64 is provided on the upper surface of the straight member 69 provided below or above the circuit board 1 so as not to interfere with the conveyance of the circuit board 1, although it is provided on the support rail 19 of FIG. A plurality of them are provided at regular intervals H. The arrangement direction of the x-direction correction marks 64 of the straight member 69 is set at a high accuracy with respect to the arrangement direction of the y-direction correction marks 63.

Alternatively, the straight member 69 provided with the x-direction correction mark 64 may not be permanently provided at the illustrated position, but may be movable such that it is retracted when the circuit board 1 is unloaded. Further, the straight member 69 has the x-direction correction mark 64
It may be omitted by providing it on an existing member that extends substantially along the y direction.

Next, the mounting operation of the electronic component of this embodiment will be described with reference to the flowchart shown in FIG. The recognition of the board mark and the y-direction correction mark in S21 to S25 is the same as that in the flowchart shown in FIG. When the recognition of the y-direction correction mark 63 is completed, the operation of recognizing the x-direction correction mark 64 is subsequently performed (S26). Here, in order to recognize the x-direction correction mark 64 on the straight member 69 shown in FIG. 11, only the Y-axis robots 23 and 24 of the XY robot 29 are operated and the transfer head 27 is moved in the y-direction to transfer. The board recognition camera 33 mounted on the mounting head 27 sequentially captures the x-direction correction marks. Thus, each correction mark is recognized to obtain the mark position (S26), and the x coordinate value of each recognized correction mark is transmitted to the control unit 53 as recognition data (S27). This recognition operation is repeated for the number m of x-direction correction marks 64 (S28).

Here, since the x-direction correction marks 64 are also provided discretely, like the y-direction correction marks 63,
It is preferable to obtain continuous coordinate data in order to correspond to an arbitrary mounting position. By this interpolation processing, the control unit 53
Then, the position x _mj , y _mj (j = 1 to 1) of each x-direction correction mark
The interpolation curve x = S (y) obtained from m) is set.

Next, in S29, the transfer head 27 is moved to the component supply section 37 of the component mounting apparatus 100, and the above S6-
Similar to S8, the suction nozzle 31 of the mounting head 43 sucks a predetermined electronic component. Then, using the board mark recognition data, the correction mark recognition data, and the component recognition data thus obtained, the mounting position of the electronic component specified in the mounting program on the circuit board 1 is calculated (S32). That is, assuming that the mounting position data of a total of N electronic components specified in the mounting program are x _pi and y _pi (i is an integer from 1 to N), the mounting positions in the robot coordinate system after correction are It can be expressed by equation (3).

X _i = x _pi + Δx _ki + S (x _pi ) + Δx _si + x _ofs Y _i = y _pi + Δy _ki + S (y _pi ) + Δy _si + y _ofs (3)

As a result, the mounting position of the electronic component expressed in the reference coordinate system is expressed in the robot coordinate system. Then, the electronic component sucked and held by the suction nozzle 31 of the transfer head 27 is moved to a predetermined mounting position by driving the XY robot 29 (S33), and the electronic component is mounted on the circuit board 1 (S34). The above operation from S29 is repeated until the final step of the mounting program,
Electronic components are mounted (S35). As a result, the X-axis robot 25 and the Y-axis robot 23 of the XY robot 29,
24 can be corrected, that is, the positional deviation due to the meandering motion in the x direction and the y direction can be corrected, and the electronic component can be more accurately aligned and mounted on the circuit board 1.

FIG. 13 is an explanatory view conceptually showing how the components are mounted with the above correction. Now, the X-axis robot 25 of the XY robot 29 and the Y-axis robots 23, 2
Consider a case in which both 4 have the characteristic of operating in a meandering manner with respect to the coordinate axes x and y of the reference coordinate system. X-axis robot 2
5, the moving locus of the transfer head 27 on the x-axis becomes a meandering curve indicated by L _rx in the figure, and the Y-axis robot 23,
The locus of movement of the transfer head on the y-axis by 24 is L in the figure.
It becomes the meandering curve shown by _ry . In the meandering locus L _ry , the transfer head 27 is moved by the Y-axis robots 23 and 24 along the straight member 69 provided with the x-direction correction mark 64, and the x-direction correction mark 64 is imaged and recognized. It is obtained from the meandering locus L _sy in which each mark position is connected by interpolation processing. Here again, the meandering loci L _rx and L _sx and the meandering loci L _ry and L _sy have the same amplitude and phase, respectively.

For example, the meandering loci L _rx and L _{ry at} the position of (x _d , y _d ) have deviation amounts of Δs _{x in} the x direction and Δs _{y in} the y direction, and (x _d , y _d The electronic component to be mounted at the position () in the figure (marked with ◇ in the figure) is set to the mounting target position by setting the position (marked with ◆ in the figure) in which the deviation amount of Δs _x and Δs _y is corrected, As a result, electronic components are mounted in the correct positions. Although only the correction of the positional deviation due to the meandering characteristic of the X-axis robot 29 is referred to in this example, the positional deviation is also corrected by the board mark recognition data and the component recognition data as described above. And

In the component mounting method according to the present invention described above, in addition to performing the recognition operation of the x-direction and y-direction correction marks for each mounting operation, for example, standing of the component mounting apparatus 100 is performed. It can be done only once when raising, or can be done every predetermined maintenance period to minimize the delay of mounting time due to the correction mark recognition operation,
It may be carried out periodically every predetermined number of mountings, every number of mounting boards, or every predetermined mounting time, or may be carried out at an arbitrary timing by the operation of the operator.

Further, the meandering characteristics of the x-direction and y-direction correction marks can be finely measured by narrowing the arrangement interval, and the accuracy of the component mounting position can be made higher. Further, each correction mark is not only provided as a sealing material on a flat surface but also a mark formed of a concave portion or a convex portion formed on a member, a narrow groove extending in one direction, a member edge portion, etc. The feature points of may be regarded as marks. Further, as a method of detecting the amount of deviation, in addition to the detection of the mark position, a reflection mirror is provided on the transfer head 27, and a spot-shaped laser beam is emitted from the base 11 or the like of the component mounting apparatus 100 to the reflection mirror. A light detection method may be used in which the reflected light is detected with high accuracy to detect the positional deviation of the transfer head 27 at each destination, and other electrical detection that detects the deviation based on a change in capacitance or the like. As a method,
A mechanical detection method may be used in which the deviation is measured by a mechanical gauge or the like.

[0061]

According to the component mounting method and component mounting apparatus of the present invention, a plurality of correction marks are linearly arranged along the moving axis direction of the moving means, while the transfer head is driven by driving the moving means. Move in the direction of the moving axis, recognize each correction mark by the image recognition unit, find the deviation amount of these correction mark positions from the straight line, and mount the components recorded in the mounting program based on the obtained deviation amount. When the mounting means is driven by driving the moving means that operates in a coordinate system different from the coordinate system in which the position of the board is managed by correcting the position, and a meandering locus occurs in the moving movement of the axis by the moving means. However, since the meandering locus is measured in advance and is feedback-corrected to the mounting position data of the mounting program, the component is stably mounted at an accurate position in which the displacement due to the meandering motion is corrected. Theft is possible.

[Brief description of drawings]

FIG. 1 is a schematic overall perspective view of a component mounting apparatus according to an embodiment of the present invention.

FIG. 2 is a partially enlarged perspective view of the configuration of the mounting head of the component mounting apparatus.

FIG. 3 is a block configuration diagram showing a main part of the component mounting apparatus.

FIG. 4 is an explanatory diagram conceptually showing the coordinate system of the component mounting apparatus.

FIG. 5 is a plan view showing an XY table provided with correction marks in the first embodiment.

FIG. 6 is a flowchart illustrating a procedure of mounting a component while correcting the component mounting position by detecting a correction mark according to the first embodiment.

FIG. 7 is an explanatory diagram showing a correction amount based on a substrate mark.

FIG. 8 is an explanatory diagram showing a state of interpolation processing of each correction mark position.

FIG. 9 is an explanatory diagram showing a shift amount of a component sucked by a suction nozzle.

FIG. 10 is an explanatory diagram conceptually showing how a component is mounted by performing the correction according to the first embodiment.

FIG. 11 is a plan view showing an XY table provided with correction marks according to the second embodiment.

FIG. 12 is a flowchart illustrating a procedure of mounting a component while correcting the component mounting position by detecting a correction mark according to the second embodiment.

FIG. 13 is an explanatory diagram conceptually showing how components are mounted by performing the correction according to the second embodiment.

FIG. 14 is an explanatory diagram of a conventional method for detecting a fixed position of a circuit board.

FIG. 15 is an explanatory diagram showing an ideal straight line trajectory along which the X axis of a conventional XY robot should originally move and a meandering trajectory.

[Explanation of reference numerals] 1 circuit board 3 electronic component 11 base 12 circuit board 19 support rail 21 XY table 23, 24 Y-axis robot 25 X-axis robot 27 transfer head 29 XY robot 31 suction nozzle 33 substrate recognition camera 41 component recognition Devices 43a, 43b, 43c, 43d Mounting head 45 Actuator 47 Motor 49 Timing belt 51 Pulley 53 Control section 55 Display means 57 Input means 59 Storage section 61 Mounting operation position 63 Correction mark (y-direction correction mark) 64 Correction mark ( x direction correction mark) 67, 67a, 67b Substrate mark 69 Straight member 100 Component mounting device H interval L interval L _rx , L _ry , L _sx , L _sy meandering locus

   ─────────────────────────────────────────────────── ─── Continued front page    F-term (reference) 5E313 AA02 AA23 CC03 CC04 EE02                       EE03 EE24 EE33 FF24 FF28                       FF31 FF32

Claims (6)

[Claims] 1. A transfer head on which a component holding unit for detachably holding a component and an image recognition unit having an image pickup camera are mounted, and a mounting destination of the held component which is arranged facing the transfer head. A moving means for moving the transfer head with respect to the substrate, and moving the transfer head parallel to the substrate surface in accordance with a mounting program in which the mounting position of the component is recorded. A component mounting method for mounting a component held by a holder at a predetermined position on a substrate, wherein a plurality of correction marks are linearly arranged along a moving axis direction of the moving unit, The transfer head is moved in the movement axis direction by driving, the correction marks are respectively recognized by the image recognizing unit, the deviation amount of these correction mark positions from the straight line is obtained, and based on the obtained deviation amount. Component mounting method characterized by correcting the mounting position of the component which is recorded on the mounting program are. 2. The moving means has two moving axes which are orthogonal to each other, and recognizes the correction marks arranged along the respective moving axis directions to determine the mounting position of the component. The correction is performed with respect to the direction.
Part mounting method described. 3. A continuous position data is generated by interpolating the recognized discrete correction mark position, and the mounting position of the component is corrected based on the continuous position data. The component mounting method according to claim 1 or 2. 4. The correction of the mounting position, in addition to the shift amount obtained by the correction mark, the shift amount of the substrate from the regular position on which the substrate is placed, the regular component holding of the component holder. 4. The method according to claim 1, wherein at least one of the deviation amounts of the parts from the position is adjusted.
The component mounting method according to claim 1. 5. A transfer head on which a component holding unit for detachably holding the component and an image recognition unit having an image pickup camera are mounted, and a mounting destination of the held component which is arranged facing the transfer head. And a moving unit that moves the transfer head with respect to the substrate, and mounts the component at a predetermined position on the substrate according to a mounting program in which the mounting position is recorded, and fixes the substrate. A plurality of correction marks provided on the substrate fixing part or in the vicinity thereof along the moving axis direction of the moving means, and driving the moving means to move the transfer head in the moving axis direction. Recognizing each of the correction marks, obtaining the deviation amount of these correction mark positions from the straight line, and the mounting position of the component recorded in the mounting program based on the obtained deviation amount. Component mounting apparatus characterized by comprising a control unit for correcting for. 6. The moving means has two moving axes which are orthogonal to each other, and the control section obtains the deviation amount for each moving axis and corrects the mounting position. 5. The component mounting apparatus according to item 5.