JP5013816B2 - Surface mount equipment - Google Patents

Description

  The present invention relates to a surface mounting apparatus, and more particularly to a surface mounting apparatus suitable for application when speeding up a mounting operation from component adsorption to mounting on a substrate.

  In a conventional surface mounting apparatus, a plurality of suction nozzles that can be moved up and down independently by a Z-axis driving unit are mounted on a mounting head that can be moved by an XY-axis driving unit, and the mounting head moves in the XY directions. At the start, all the suction nozzles are raised to a height that does not come into contact with obstacles such as parts mounted on the board or planned maximum height, or camera units on the surface mount device. By lowering the target or mounting target suction nozzle, the suction or mounting of the component is performed while controlling so that the tip of the nozzle (or suction component) does not come into contact with the component already mounted on the substrate.

  Similarly, as a technique for preventing contact with an obstacle, Patent Document 1 stores the position and height of an obstacle between the component supply device and the circuit board, and synchronizes with the passage of the obstacle. Thus, a method has been proposed in which the nozzle moving time is reduced by lowering the nozzle.

JP 2004-303029 A

  However, depending on the technique proposed in Patent Document 1, a large amount of data is required to store all the positions and heights of obstacles, and the machine may be modified or a new unit may be attached. In such a case, since it is necessary to newly register the position and height of the unit or the like, there is a problem that the addition and change cannot be flexibly handled.

  The present invention has been made to solve the above-described conventional problems, and realizes high-speed component mounting operation without storing all the planar positions and heights of obstacles such as components on the board. It is an object of the present invention to provide a surface mount device capable of performing the above.

The present invention provides an XY-axis driving unit that moves a mounting head in a plane direction, a plurality of suction nozzles that are mounted on the mounting head and can be moved up and down by a Z-axis driving unit, and a plurality of components that supply parts to a suction area A surface mounting apparatus that includes a feeder, moves the mounting head above the suction area, sucks a component by a target suction nozzle, and then moves the mounting head onto the substrate to mount the suction component In the above, the height of the suction nozzle when the mounting head is moved by the XY axis driving means is the first height that does not contact the feeder, and the first height that does not contact the obstacle between the suction area and the substrate and on the substrate. When the height is set to 2 and the parts are successively picked up sequentially by a plurality of suction nozzles, all the suction nozzles are held at the second height and the mounting head is moved above the suction area. When all the suction nozzles to be suctioned are lowered to the first height and the target suction nozzle is lowered from the first height to suck and raise the parts, the suction parts are moved to the first height. Control means for controlling the mounting head to move to the next suction position when it is determined that the mounting head is exceeded, and the mounting head includes the presence / absence of components sucked by the plurality of suction nozzles, respectively. As the component presence / absence detection sensor to be detected, a pressure sensor that detects the presence / absence of a suction component based on the differential pressure before and after the suction of each component for each suction nozzle, and a projection that is opposed to the position where the nozzle tip can be raised for each suction nozzle When an optical sensor that detects the presence / absence of an adsorbing part is installed by an optical part and a light receiving part, and the control means adsorbs the part with a small-diameter nozzle that cannot detect the presence / absence of the part by the pressure sensor In order to actually detect, the suction nozzle is raised to the installation position of the optical sensor, and when the parts are sucked by other suction nozzles, the presence of the parts is confirmed by the pressure sensor at the time of suction. Thereafter, the problem is solved by performing control to raise the suction nozzle to the second height .

In the present invention, for the small-diameter nozzle, the control means counts suction errors generated for each feeder based on the detection result of the optical sensor, and continues the parts from the feeder whose error occurrence rate exceeds the reference value. At the time of suction, after the presence of the suction component is confirmed by the optical sensor, the mounting head may be controlled to move the suction nozzle to the next suction position.

  Depending on the purpose of the XY movement operation of the mounting head by the XY-axis driving means when mounting a component on a substrate with a surface mount device, “suction position → suction position”, “suction position → mounting position”, “mounting position → There are four types of movement patterns, “Mounting position” and “Mounting position → Suction position”. In the case of movement patterns including the mounting position, nozzles are mounted on the mounted components so that the mounting head can pass over the substrate It is necessary to raise the suction nozzle by the Z-axis drive means to a height at which (or the suction part) does not contact.

  However, when the mounting head is moved from the suction position to the suction position in the XY direction, the mounting head does not pass over the substrate, so the mounting head is simply raised by the Z-axis drive means to a height at which it does not contact the feeder. It has been found that XY movement can be performed.

  The present invention has been made on the basis of the above knowledge. According to the present invention, the mounting head on which a plurality of suction nozzles are mounted is moved by XY movement of “suction position → suction position” by the XY axis driving means. When performing continuous suction that picks up parts sequentially by each nozzle, the work efficiency of continuous suction operation can be improved by setting the height of the suction nozzle in the Z-axis direction so that it does not contact the feeder. It is possible to realize a high-speed mounting operation for mounting the substrate on the substrate.

  Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings.

  FIG. 1 is a plan view showing an outline of a surface mounting apparatus applied to the first embodiment of the present invention.

  In the surface mounting apparatus 1, the printed circuit board 3 is transported by the substrate transport apparatus 2 and can be positioned at the illustrated position. Further, in this surface mounting apparatus 1, a plurality of rows of tape feeders 4 are arranged at the upper and lower positions in the figure, and the components to be supplied to these feeders 4 are the mounting head 5, the X-axis linear motor 7, the left and right Y An XY-axis driving means comprising an axis linear motor 6 is moved and positioned in the X and Y directions, and is adsorbed by the adsorbing nozzle 8 mounted thereon, and then the mounting head 5 is moved onto the printed circuit board 3. It is supposed to be mounted on.

  In FIG. 2, the outline | summary of the mounting head 5 employ | adopted as this embodiment is expanded and shown. In this mounting head 5, a plurality of (four in this example) suction nozzles 8 arranged in the X direction can be moved up and down by Z axis driving means (not explicitly shown) that are independently driven. The parts can be sucked by a vacuum device (not shown).

  In addition, in the plurality of suction nozzles 8 mounted on the mounting head 5, two types of component presence / absence detection sensors, a pressure sensor and an optical sensor, are installed to detect the presence / absence of the component sucked for each suction nozzle. Has been.

  As shown in FIG. 2, the pressure sensor 9 is provided at the tip of a vacuum tube 9 </ b> A that is connected to each suction nozzle and supplies negative pressure to the tip. The optical sensor 10 is a laser sensor that is a combination of a laser light projecting unit 10A and a light receiving unit 10B that are disposed to face the mounting head 5 with the suction nozzles 8 therebetween.

  Detection of the suction component by the pressure sensor 9 is performed in a short time immediately after suction because of the differential pressure before and after the suction, but in the case of the optical sensor 10, the suction nozzle is sucked by the feeder 4 by the Z-axis driving means. It is necessary to raise from the height to the sensor height L where the light projecting / receiving portions 10A and 10B on the head are. Therefore, since the inner diameter of the nozzle is usually small, it is detected by the optical sensor 10 for the small diameter nozzle that cannot detect the presence or absence of the suction component by the differential pressure before and after suction, and by the pressure sensor 9 for the other suction nozzles 8. Yes.

  In FIG. 3, the outline | summary of the control system with which the surface mounting apparatus of this embodiment is provided is shown.

  The control system includes a CPU 20 that executes various calculations for controlling the component mounting operation. The CPU 20 includes an I / O control unit 21, a laser sensor control board 22, an axis control board 23, an image processing board 24, and the like. Are connected to each other by a bus, and are connected to a monitor 25 for displaying calculation results and an HDD (Hard Disk Drive) 26 for storing control programs, control data, and the like.

  The I / O control unit 21 is connected to an actuator 27 such as a vacuum sensor (pressure type sensor) 9 or a vacuum solenoid valve. The laser sensor control board 22 has a laser sensor 10 and an axis control board. A servo amplifier 28 for driving a servomotor 29 constituting each linear motor (axis driving means) such as the XYZ axes is connected to 23, and a CCD camera 30 is connected to the image processing board 24.

  In the present embodiment, this control system gives an image of the height of the suction nozzle 8 when the mounting head 5 is moved in the XY direction together with the suction height (component height) Z0 and the optical sensor height L in FIG. As shown, the first height Z1 that does not contact the feeder Z1 and the second height that does not contact obstacles such as parts between the suction area and the substrate and on the substrate (passing the substrate) (Possible height) Z2 is set.

  When the components are continuously sucked by the plurality of suction nozzles 8, the suction head 8 is positioned at the tip of the feeder 4 on the substrate side with all the suction nozzles 8 held at the second height. After moving upward 4A, all of the suction nozzles 8 that are scheduled to be sucked are lowered to the first height Z1.

  Thereafter, the target suction nozzle 8 is raised. At this time, when it is determined that the suction component exceeds the first height Z1, control is performed to move the mounting head 5 to the next suction position. Yes. Note that the position of each axis direction of XYZ is determined by the output of an encoder (not shown) incorporated in each corresponding driving means.

  Next, the operation of this embodiment will be described with reference to the flowchart of FIG. 5 by taking an example of an adsorption cycle in which continuous adsorption is performed by the plurality of adsorption nozzles.

  First, the mounting head 5 is moved by the XY linear motors 6 and 7 from the last mounting point on the substrate 3 of the component sucked in the previous suction cycle to the first suction point of the feeder that first picks up the component in the next suction cycle. (Steps 1 and 2). During this movement, the height of the Z-axis of all the suction nozzles 8 is at a substrate-passable height (second height) Z2 above the maximum component height on the substrate 3.

  After the operation of moving the mounting head 5 to the first suction point by the XY linear motors 6 and 7 is completed (“Yes” in step 2), the Z-axis height of the target nozzle to be first suctioned is the height Z2 that can pass through the substrate. The suction nozzle is lowered to the suction height Z0. At this time, the nozzles that are scheduled to be picked up in the current suction cycle are searched, and the suction movable height that does not contact all the planned nozzles with the feeder 4 (first height). E) Lower to Z1 simultaneously (step 3).

  Next, the target nozzle 8 coinciding with the suction position in the suction area 4A is lowered to the suction height (component height) Z0 (step 4), and the component suction by vacuum is performed (step 5).

  After the component suction, the target nozzle 8 that has been lowered to the suction height is raised (hereinafter, this movement is also referred to as a suction rise). It is determined whether or not the vacuum check can be performed (step 6).

  Regardless of the determination in step 6, the target nozzle 8 immediately starts to rise. However, the target coordinate in the Z-axis direction for raising the target nozzle 8 at that time differs depending on the determination result, and when the vacuum check is possible, the target coordinate is detected immediately, and therefore rises toward the substrate passing height Z2. Start (step 7). On the other hand, when the vacuum check is impossible, the optical sensor 10 needs to actually detect it, and therefore, the rising is started toward the component presence / absence detection height (optical sensor height) L (step 8).

  After the target nozzle 8 starts to rise, the next component suction is performed because the planned nozzle still remains, that is, when the next XY movement position is the suction position (“Yes” in step 9), the mounting head 5 Does not pass over the substrate 3, when it is detected that the lower surface of the part to which the Z-axis coordinate is sucked has passed the suction movement height Z 1 (“Yes” in step 10), the XY-axis linear motor 6, 7, even if the target nozzle 8 is moving upward toward the target coordinate in the Z-axis direction, the mounting head 5 is moved to the next suction position in Step 1. In the second suction operation, since the target nozzle 8 has already been lowered to the suction movable height Z1, the nozzle 8 can be lowered to the suction height Z0 in a time earlier than the first. The same operation can be repeated for the third and subsequent times.

  In this way, when the last suction rise order is reached in the current suction cycle (“No” in step 9), the next movement coordinate in the XY directions becomes the mounting point. Accordingly, since the mounting head 5 passes over the substrate 3, it waits for the movement by the Z-axis linear motor to reach the target coordinates only in this case (“Yes” in step 11). Thereafter, the XY axis linear motors 6 and 7 are activated to move the mounting head 5 onto the substrate 3 and shift to the mounting operation.

  According to the present embodiment described in detail above, the height of the nozzle when moving the mounting head 5 in the XY direction is limited to the movement in the suction area 4A (first height that does not contact the feeder) Z1, and XY It is possible to reduce the vertical movement time of the suction nozzle by the Z-axis linear motor during suction by setting two types of height Z2 that can move in the entire direction (second height that does not contact the maximum height part) Z2 it can. As a result, it is possible to improve the efficiency of the continuous suction operation, and thus improve the efficiency of the entire mounting operation.

  Next, a second embodiment according to the present invention will be described.

  The continuous adsorption operation according to the first embodiment shown in FIG. 5 has the following drawbacks.

  Even if it is determined in step 6 that the target nozzle 8 cannot be vacuum-checked, if the next is component suction, the mounting head 5 is moved XY when the nozzle 8 exceeds the suction movable height Z1 ( Steps 8, 9, 10, 1).

  In this way, for small-diameter nozzles that cannot be vacuum checked, the next XY movement is made without checking for the presence or absence of parts. Reaches the height L of the optical sensor 10, and when it is confirmed that there is no part, it is necessary to re-suck the same part.

  For this reason, when it is desired to perform a suction retry operation, the movement of returning the mounting head 5 by the XY-axis linear motors 6 and 7 enters the original suction position. Therefore, when the adsorption condition is poor and the retry operation occurs frequently, the mounting efficiency may be lowered. Such deterioration of the adsorption condition is mostly caused by parts and feeders.

Therefore, in the present embodiment, as a countermeasure, the retry rate (error occurrence rate) is monitored for each feeder, and only the feeder with a high retry rate does not move the mounting head 5 immediately after suction, but moves the optical sensor when the suction rises. After confirming the presence / absence of the component at the height L, a mechanism is provided for changing the sequence so that the XY movement is started.

  FIG. 6 shows a flowchart for monitoring the retry rate.

  First, the CPU (control means) 20 sets a specified count (for example, 100 times) as the reference number of times for determination, and clears the counters for the suction count and the retry count (step 21). Next, every time the adsorption is executed, the adsorption count is incremented by 1 (steps 26 and 27). If the adsorption fails, the retry count is incremented by 1 (steps 24 and 25). The adsorption operation is repeated until the adsorption count exceeds the specified count (step). 26).

  If the specified count is exceeded, the retry count in the specified adsorption count is calculated by dividing the total number of retries by the total count up to that point (step 27). (“Yes” at step 28), the presence / absence of components is confirmed by the optical sensor 10 and then the XY movement of the mounting head 5 is started, and the “component presence / absence confirmation mode” described below is set (step 29). This mode is continued until the adsorption condition is improved.

  If not exceeded (“No” in step 28), the “part presence / absence skip mode” for performing the process according to the flowchart of FIG. 5 according to the first embodiment for skipping the part confirmation is set (step 30).

  FIG. 7 shows an operation sequence of the “part presence / absence confirmation mode” set in step 29.

  In this flowchart, steps 31 to 38 are the same as steps 1 to 8 in FIG.

  In the present embodiment, the suction sequence after steps 37 and 38 has a feature of “part presence / absence check mode”.

  Specifically, after the target nozzle starts to rise in the Z-axis direction in steps 37 and 38, the mounting head 5 does not move in the XY direction, and the target nozzle 8 that can be vacuum checked passes through the substrate. In the case of the target nozzle 8 with the possible height Z2 that cannot be vacuum-checked, the optical sensor height L is waited for the completion of movement (rise) in the Z direction to each target coordinate (step 39).

  When reaching the target height of the target nozzle 8 is completed, if the vacuum check is possible, check with the pressure sensor 9 just in case (steps 40 and 41). If the vacuum check is impossible, the optical sensor 10 actually The presence or absence of parts is confirmed (steps 40 and 42).

If the presence of a component is confirmed (“Yes” in step 43), if there is a next component, the mounting head 5 is moved to the suction position. If there is no component, a suction retry for the same component is performed. Perform (“NO” in step 43). This suction retry operation corresponds to performing the processing after step 34 for lowering the target nozzle 8 as it is because the mounting head 5 is not moved XY.

  According to the present embodiment described in detail above, the retry rate is monitored, and the adsorption ascending sequence is switched according to the adsorption condition, whereby the optimum adsorption sequence is automatically selected for each feeder, and the drawbacks of the first embodiment can be compensated. it can.

1 is a schematic plan view showing the appearance of a surface mount device according to a first embodiment of the present invention. The front view which shows the outline | summary of the mounting head with which the said surface mounting apparatus is equipped The block diagram which shows the outline | summary of the control system with which the said surface mounting apparatus is equipped Diagram showing an image of target coordinates in the Z direction for moving the suction nozzle up and down The flowchart which shows the sequence of the continuous adsorption | suction operation | movement by 1st Embodiment. Flow chart showing retry rate monitoring sequence The flowchart which shows the operation | movement sequence in the components presence confirmation mode by 2nd Embodiment.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 ... Surface mount apparatus 2 ... Board | substrate conveyance apparatus 3 ... Printed circuit board 4 ... Feeder 4A ... Suction area 5 ... Mount head 6 ... Y-axis linear motor (drive means)
7 ... X-axis linear motor (drive means)
8 ... Adsorption nozzle 9 ... Vacuum sensor 10 ... Optical sensor (laser sensor)
20 ... CPU
21 ... I / O control unit 22 ... Laser sensor control board 23 ... Axis control board 24 ... Image processing board

Claims (2)

XY axis driving means for moving the mounting head in the plane direction, a plurality of suction nozzles mounted on the mounting head and movable up and down by the Z axis driving means, and a plurality of feeders for supplying parts to the suction area And
In the surface mounting apparatus that moves the mounting head above the suction area, sucks the component by the target suction nozzle, and then moves the mounting head onto the substrate to mount the suction component.
The height of the suction nozzle when the mounting head is moved by the XY axis driving means is a first height that does not contact the feeder, and a second height that does not contact the obstacle between the suction area and the substrate and on the substrate. Set
When sequentially sucking parts with a plurality of suction nozzles, after holding all the suction nozzles at the second height and moving the mounting head above the suction area,
When lowering all the suction nozzles to be suctioned to the first height and lowering the target suction nozzle from the first height to suck and raise the parts,
Control means for performing control to move the mounting head to the next suction position when it is determined that the suction component has exceeded the first height ;
In the mounting head, as a component presence / absence detection sensor for detecting the presence / absence of a component sucked by the plurality of suction nozzles,
A suction sensor that detects the presence or absence of a suction component based on the differential pressure before and after the suction of each component for each suction nozzle, and a light projecting unit and a light receiving unit that are arranged opposite each other at a position where the nozzle tip can be raised for each suction nozzle And an optical sensor that detects the presence or absence of
When the control means sucks a component with a small-diameter nozzle that cannot detect the presence or absence of the component by the pressure sensor, control is performed to raise the suction nozzle to the installation position of the optical sensor for actual detection. When a component is sucked by another suction nozzle, the surface is controlled to raise the suction nozzle to the second height after the presence of the component is confirmed by the pressure sensor at the time of suction. Mounting device. For the small-diameter nozzle, the control means counts the suction error generated for each feeder from the detection result of the optical sensor, and when the parts are continuously sucked from the feeder whose error occurrence rate exceeds the reference value. 2. The surface mounting apparatus according to claim 1, wherein after the presence of the suction component is confirmed by the optical sensor, the mounting head is controlled to move the suction nozzle to the next suction position.

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