JP2024036731A - Component placement device and control method in the component placement device - Google Patents

Abstract

[Problem] To provide a component mounting device and a control method for the component mounting device that can improve the mounting accuracy of components by reducing the tension remaining in the belt that transmits the rotation of the motor shaft to the nozzle shaft. [Solution] The device includes a nozzle shaft 21 extending in the vertical direction, a nozzle 22 attached to the lower end of the nozzle shaft 21, a motor 33, a belt 54 that is stretched between a motor shaft 33J, which is the rotating shaft of the motor 33, and the nozzle shaft 21 and transmits the rotation of the motor shaft 33J to the nozzle shaft 21, and a control device that controls the rotation of the motor shaft 33J. The control device rotates the motor shaft 33J in one direction to rotate the nozzle shaft 21, and then rotates the motor shaft in a return direction opposite to the one direction so that the tension remaining in the belt 54 is reduced. [Selected Figure] Figure 4

Description

TECHNICAL FIELD The present invention relates to a component mounting device that attaches components to a substrate by adsorbing components to a nozzle attached to the lower end of a nozzle shaft extending in the vertical direction, and a control method in the component mounting device.

2. Description of the Related Art Conventionally, a component mounting apparatus is known in which a mounting head picks up a component and mounts it on a board. The mounting head included in the component mounting device includes a nozzle at the lower end of a nozzle shaft extending in the vertical direction, and picks up the component by adsorbing it to the nozzle. The nozzle shaft is rotatable around the vertical axis because the components must be mounted at a predetermined mounting angle with respect to the board. The nozzle shaft is connected to the rotating shaft of the motor (motor shaft) via a belt, and by transmitting the rotation of the motor shaft to the nozzle shaft via the belt, the nozzle can be rotated (e.g. , Patent Document 1 below).

Patent No. 4608772

However, as mentioned above, the belt that transmits the rotation of the motor shaft to the nozzle shaft is often made of an elastic material such as rubber, and frictional resistance etc. acts between the nozzle shaft and its supporting part, causing the nozzle to move. When the rotation of the shaft is prevented, the belt stretches and tension remains there. If tension remains in the belt, not only will the control of the rotational position of the nozzle shaft become inaccurate, but also the nozzle shaft will be pulled by the belt and rotate slightly after positioning, resulting in a decrease in the accuracy of parts placement. There was a risk.

SUMMARY OF THE INVENTION Therefore, an object of the present invention is to provide a component mounting device and a control method for the component mounting device, which can reduce the tension remaining in the belt that transmits the rotation of the motor shaft to the nozzle shaft and improve the precision of component mounting. shall be.

The component mounting device of the present invention includes a nozzle shaft extending in the vertical direction, a nozzle attached to the lower end of the nozzle shaft, a motor, and a component mounting device mounted between the motor shaft, which is a rotation axis of the motor, and the nozzle shaft. The component mounting device includes a belt that is passed around and transmits the rotation of the motor shaft to the nozzle shaft, and a control section that controls the rotation of the motor shaft, and that attaches the component to the board by adsorbing the component to the nozzle. After rotating the motor shaft in one direction to rotate the nozzle shaft, the control unit rotates the motor shaft in the opposite direction to the first direction so that tension remaining in the belt is reduced. Rotate in the return direction.

A control method for a component mounting apparatus of the present invention includes a nozzle shaft extending in the vertical direction, a nozzle attached to the lower end of the nozzle shaft, a motor, a motor shaft that is a rotation axis of the motor, and the nozzle shaft. A control method for a component mounting apparatus for attaching a component to a board by adsorbing the component to the nozzle, the belt being stretched between the belts and transmitting the rotation of the motor shaft to the nozzle shaft. After rotating the nozzle shaft in one direction, the motor shaft is rotated in a return direction opposite to the first direction so that the tension remaining in the belt is reduced.

According to the present invention, it is possible to reduce the tension remaining in the belt that transmits the rotation of the motor shaft to the nozzle shaft, thereby improving the mounting accuracy of parts.

A perspective view of a component mounting device according to an embodiment of the present invention A plan view of a component mounting device according to an embodiment of the present invention A partially transparent perspective view of a mounting head included in a component mounting device according to an embodiment of the present invention A cross-sectional perspective view of a part of a mounting head included in a component mounting device according to an embodiment of the present invention A simplified plan view showing the arrangement of a motor and a rotation transmission mechanism included in a mounting head of a component mounting device according to an embodiment of the present invention. A block diagram showing a control system of a component mounting device according to an embodiment of the present invention A simplified plan view of a motor and a rotation transmission mechanism included in a mounting head of a component mounting device according to an embodiment of the present invention. A simplified plan view of a motor and a rotation transmission mechanism included in a mounting head of a component mounting device according to an embodiment of the present invention. (a) Graph showing an example of a time change in the rotational speed of the motor shaft of the component mounting device according to an embodiment of the present invention; (b) Graph showing an example of a time change in the nozzle shaft rotational speed corresponding to the amount of motor shaft rotation A diagram showing a state in which it is checked whether the nozzle shaft is located at the target rotational position when the motor shaft is rotated in anticipation of the amount of return rotation in the component mounting device according to an embodiment of the present invention. A diagram showing a state in which it is checked whether the nozzle shaft is located at the target rotational position when the motor shaft is rotated in anticipation of the amount of return rotation in the component mounting device according to an embodiment of the present invention.

Embodiments of the present invention will be described below with reference to the drawings. 1 and 2 show a component mounting apparatus 1 in an embodiment of the present invention. The component mounting device 1 is a device that mounts a component BH on a board KB sent from the upstream side and carries it out to the downstream side. Here, for convenience of explanation, the transport direction of the board KB in the component mounting apparatus 1 is assumed to be the X direction, the horizontal direction orthogonal to the X direction is assumed to be the Y direction, and the vertical direction is assumed to be the Z direction.

1 and 2, the component mounting apparatus 1 includes a base 11, a conveyor 12, a tape feeder 13, a mounting head 14, a head moving mechanism 15, and a component camera 16. The conveyor 12 is provided on the base 11, supports both ends of the substrate KB from below, and conveys it in the X-axis direction.

The tape feeders 13 are attached to both ends of the base 11 in the Y direction in parallel in the X direction. Each tape feeder 13 pulls out a carrier tape (both not shown) from a reel, conveys it, and supplies the component BH to a component supply port 13K provided at the end on the conveyor 12 side. Note that the tape feeder 13 is an example of a component supply device, but there are other component supply devices such as a tape feeder that supplies taped radial components and axial components, and a tray feeder that supplies components stored in a tray. Available for use.

As shown in FIG. 3, the mounting head 14 includes a plurality (four in this case) of nozzle shafts 21 extending downward. A nozzle 22 for sucking the component BH is attached to the lower end of each nozzle shaft 21. The mounting head 14 can generate suction force to hold the component BH at the lower end of the nozzle 22 by supplying vacuum pressure into a vacuum supply path formed inside the nozzle shaft 21 .

In FIG. 1, the head moving mechanism 15 includes a fixed beam 15a provided on the base 11 and extending in the Y direction, and a movable beam 15b having one end supported by the fixed beam 15a and extending in the X direction. A mounting head 14 is supported on the movable beam 15b. The fixed beam 15a is equipped with a mechanism for moving the movable beam 15b in the Y direction, and the movable beam 15b is equipped with a mechanism for moving the mounting head 14 in the X direction. The head moving mechanism 15 moves the mounting head 14 in a horizontal plane (XY plane) by moving the movable beam 15b in the Y direction and moving the mounting head 14 in the X direction.

In FIGS. 1 and 2, the component cameras 16 are provided at two locations on the base 11, sandwiching the conveyor 12 in the Y direction. Each component camera 16 has its imaging field of view facing upward.

In FIG. 3, the mounting head 14 includes a base portion 31 that holds the four nozzle shafts 21 in a posture extending in the Z direction, and four elevating portions 32 arranged above the base portion 31. Each elevating section 32 is composed of a cylinder or a motor, and individually raises and lowers the four nozzle shafts 21 relative to the base section 31.

3 and 4, a motor 33 and a rotation transmission mechanism 34 are provided within the base portion 31. As shown in FIG. The motor 33 has a rotating shaft (motor shaft 33J) facing downward, and a drive pulley 51 is attached to the lower end of the motor shaft 33J.

The rotation transmission mechanism 34 is a mechanism that transmits the rotation of the motor shaft 33J to the four nozzle shafts 21, and includes a plurality of (here, four) driven pulleys 52 attached to each of the four nozzle shafts 21, and a plurality of (here, four) driven pulleys 52 attached to each of the four nozzle shafts 21. It consists of three idle pulleys 53 and a belt 54. The driving pulley 51, the four driven pulleys 52, and the three idle pulleys 53 are each toothed pulleys and are located at the same height (in the horizontal plane). The belt 54 is a belt (timing belt) having teeth that engage with the teeth of each of the drive pulley 51, four driven pulleys 52, and three idle pulleys 53, and is made of an elastic body such as rubber.

4 and 5, the belt 54 includes a drive pulley 51, a first driven pulley 52 (first driven pulley 52a), a first idle pulley 53 (first idle pulley 53a), and a second idle pulley 53 (first idle pulley 53a). driven pulley 52 (second driven pulley 52b), third driven pulley 52 (third driven pulley 52c), second idle pulley 53 (second idle pulley 53b), fourth driven pulley It is looped around the pulley 52 (fourth driven pulley 52d) and the third idle pulley 53 (third idle pulley 53c) in this order.

With the rotation transmission mechanism 34 having such a configuration, when the motor shaft 33J rotates, the four driven pulleys 52 and the three idle pulleys 53 rotate in the same direction as the rotation direction of the motor shaft 33J via the belt 54. The motor shaft 33J can be rotated in either forward or reverse directions, and by changing the rotation direction of the motor shaft 33J, the rotation directions of the four nozzle shafts 21 can be switched.

The four driven pulleys 52 have the same diameter, and the four driven pulleys 52 rotate by the same amount of rotation through the belt 54. Therefore, when the motor shaft 33J rotates with the component BH being attracted to the nozzle 22, the four nozzle shafts 21 (therefore, the four nozzles 22) rotate in the same direction and by the same amount of rotation, and the component BH is attracted to the nozzle 22. Part BH rotates in the same direction with the same amount of rotation.

Each nozzle shaft 21 and the corresponding driven pulley 52 are connected by spline fitting. Therefore, the elevating section 32 can move the nozzle shaft 21 (driven pulley 52) up and down without changing the rotational position of the nozzle shaft 21 (driven pulley 52).

FIG. 6 shows a control system of the component mounting apparatus 1. A control device 60 provided in the component mounting apparatus 1 controls each operation of the conveyor 12, tape feeder 13, mounting head 14, head moving mechanism 15, and component camera 16, as shown in FIG.

The control device 60 controls the operation of the transport conveyor 12 to transport the board KB and position it to the work position, and controls the operation of the tape feeder 13 to supply the component BH to the component supply port 13K of the tape feeder 13. let The control device 60 also controls the operation of the lifting section 32 to raise and lower the nozzle shaft 21 (that is, the nozzle 22), and operates the motor 33 through the motor driver 33D (FIG. 6). The control device 60 also controls the supply of vacuum pressure into each nozzle shaft 21, thereby generating a vacuum adsorption force to pick up the component BH at the lower end of the nozzle 22.

In FIG. 6, a control device 60 controls the imaging operation of the component camera 16 through a camera control image recognition unit 61. The camera control image recognition unit 61 acquires an image captured by the component camera 16 and performs image recognition based on the image.

As described above, when the motor shaft 33J rotates, the rotation is transmitted to the nozzle shaft 21 via the belt 54, and the nozzle shaft 21 rotates. Therefore, the nozzle shaft rotation amount Θ can be controlled by the motor shaft rotation amount Φ, but since the belt 54 is made of an elastic body, there is frictional resistance between the nozzle shaft 21 and the driven pulley 52 and their supporting parts. If the rotation of the nozzle shaft 21 is hindered due to the rotation of the nozzle shaft 21, the belt 54 is stretched and tension is generated, which not only makes the positioning control of the rotational position of the nozzle shaft 21 inaccurate, but also causes the rotation of the nozzle shaft 21 after positioning. is pulled by the belt 54 and rotates, and as a result, there is a risk that the mounting accuracy of the component BH will be reduced.

When the shaft rotation amount Θ is controlled by the motor shaft rotation amount Φ, if the belt 54 stretches, the shaft rotation amount Θ cannot be rotated by the rotation of the motor shaft 33J (when the belt 54 does not stretch). The amount of rotation will be smaller than the amount of rotation possible. Therefore, in the component mounting apparatus 1 (control method in the component mounting apparatus 1) according to the present embodiment, if the motor shaft 33J is originally (when no elongation occurs in the belt 54), the shaft rotation amount Θ is the target rotation amount Θm. After the motor shaft is rotated to the rotation amount Φ2 (= Φ1 + ΔΦ), which is the additional rotation amount ΔΦ in anticipation of the elongation of the belt 54 added to the motor shaft rotation amount Φ1 that should reach , the tension generated in the belt 54 (Fig. 7). The motor shaft 33J is returned to the opposite direction (return direction) and rotated by the amount of rotation Φd so that the rotation amount is reduced (FIG. 8). Note that even if the amount of reduction in the tension remaining in the belt 54 is small, there is an effect, so the return rotation amount Φd may be constant regardless of the motor shaft rotation amount Φ.

FIG. 9(a) shows the time change in the rotational speed of the motor shaft 33J when the motor shaft 33J is rotated as described above, and FIG. 9(b) shows the nozzle shaft 21 corresponding to FIG. 9(a). shows the change in rotational speed over time. As can be seen from FIGS. 9(a) and (b), after rotating the motor shaft 33J in one direction (the positive (+) direction of the vertical axis in FIG. 9(a)), When the nozzle shaft 21 is rotated in the return direction (the negative (-) direction of the vertical axis in FIG. 9(a)), the nozzle shaft 21 rotates in one direction (as shown in FIG. 9(b)) as the motor shaft 33J rotates in one direction. However, even if the motor shaft 33J subsequently rotates in the return direction, the motor shaft 33J rotates in the opposite direction (in the negative (-) direction of the vertical axis in FIG. 9(b)). ) direction). This is because when the motor shaft 33J is rotated in the return direction, the elongation of the belt 54 that has occurred up to that point is only reduced.

It is necessary to confirm in advance whether or not the shaft rotation amount Θ actually reaches the target rotation amount Θm by rotating the motor shaft 33J to the rotation amount Φ2 (=Φ1+ΔΦ). FIG. 10 shows how the confirmation is being carried out. While confirming the state in which the motor shaft 33J has rotated to the rotation amount Φ2=(Φ1+ΔΦ) based on the output of the motor driver 33D, the nozzle 22 is checked using the component camera 16. The rotational position is confirmed and the data acquisition unit 63 acquires the required data. At this time, it is preferable that the nozzle 22 has a pattern so that its rotational position (rotation angle) can be seen when viewed from below.

11 differs only in that the encoder 21E detects the shaft rotation amount Θ detected through the component camera 16 in FIG. 10, and the data acquisition unit 63 acquires data on the shaft rotation amount Θ detected by the encoder 21E. It is. The procedure for checking whether the shaft rotation amount Θ has reached the target rotation amount Θm when the motor shaft 33J is rotated to the motor shaft rotation amount Φ2 (=Φ1+ΔΦ) in anticipation of the return rotation amount Φd is shown in FIG. 10 above. The same is true for .

When the component mounting apparatus 1 configured as described above executes the work of mounting the component BH onto the board KB (component mounting work), the control device 60 first operates the conveyor 12 to load the component BH onto the board KB from the upstream process side. The sent board KB is received, carried in, and positioned at a predetermined work position. Once the substrate KB is positioned at a predetermined working position, the head moving mechanism 15 and the mounting head 14 work together to repeat mounting turns.

In one mounting turn, the mounting head 14 holds (adsorbs) the component BH supplied by the tape feeder 13 with the nozzle 22, and moves above the board KB along a path that causes the component camera 16 to image (recognize) the component BH. Therefore, it is located above the substrate KB. Then, by lowering the nozzle shaft 21 above the target mounting position on the board KB, the component BH held by the nozzle 22 is mounted on the board KB.

At this time, the control device 60 determines, for each component BH, that the rotation amount (shaft rotation amount Θ) of the nozzle shaft 21 to which the nozzle 22 holding the component BH is attached is a target rotation corresponding to the mounting angle of the component BH. After rotating the nozzle shaft 21 in the above-described manner (control method in the component mounting apparatus 1) so that the amount Θm is achieved, only the nozzle shaft 21 is lowered by the lifting section 32, and the component BH is mounted on the board KB. When a series of operations consisting of the rotation and lowering of the nozzle shafts 21 are sequentially performed for the four nozzle shafts 21, one mounting turn is completed.

The control device 60 repeats the mounting turns according to such a procedure, and when all the components BH to be mounted are mounted on the board KB, the control device 60 operates the conveyor 12 to transfer the board KB to the downstream process of the component mounting device 1. Carry it out to the side. This completes the component mounting work for each board KB.

As explained above, in the component mounting apparatus 1 (control method in the component mounting apparatus) according to the present embodiment, the rotation of the motor shaft 33J is controlled so that the rotation amount of the nozzle shaft 21 (shaft rotation amount Θ) is set to the target rotation amount. Θm, the tension remaining in the belt 54 is reduced after the motor shaft 33J is rotated in one direction to rotate the nozzle shaft 21 until the shaft rotation amount Θ matches the target rotation amount Θm. The motor shaft 33J is rotated in the return direction opposite to the first direction so as to rotate the motor shaft 33J in the return direction opposite to the first direction. For this reason, the correspondence between the rotation amount of the motor shaft 33J as the input shaft (motor shaft rotation amount Φ) and the rotation amount of the nozzle shaft 21 as the output shaft (shaft rotation amount Θ) is maintained in a normal state without deviation. At the same time, it is possible to prevent the nozzle shaft 21 from rotating due to the tension remaining in the belt 54, so that the part BH picked up by the nozzle 22 can be positioned at the correct mounting angle, and then the part BH can be removed. It becomes possible to mount the component BH on the board KB, and the mounting accuracy of the component BH can be improved.

Although the embodiments of the present invention have been described so far, the present invention is not limited to the above-described embodiments, and various modifications and the like are possible. For example, in the above-described embodiment, the number of nozzle shafts 21 (and therefore the number of nozzles 22) included in the mounting head 14 was four, but this is just an example, and the number is not limited.

Furthermore, in the above-described embodiment, the explanation was given on the assumption that all of the plurality of nozzle shafts 21 included in the mounting head 14 rotate by the same amount of rotation (shaft rotation amount Θ) in accordance with the rotation of the motor shaft 33J. However, each of the plurality of nozzle shafts 21 does not necessarily rotate by the same amount of rotation in accordance with the rotation of the motor shaft 33J. Therefore, the relationship between the motor shaft rotation amount Φ and the shaft rotation amount Θ is grasped (data is taken) for each nozzle shaft 21, and the shaft rotation amount Θ is controlled by the motor shaft rotation amount Φ for each nozzle shaft 21 individually. It is preferable that the

Provided are a component mounting device and a control method for the component mounting device that can reduce tension remaining in a belt that transmits rotation of a motor shaft to a nozzle shaft and improve component mounting accuracy.

1 Component mounting device 21 Nozzle shaft 22 Nozzle 33 Motor 33J Motor shaft 34 Rotation transmission mechanism 54 Belt 60 Control device (control unit)
Φ Motor shaft rotation amount ΔΦ Additional rotation amount Φd Return rotation amount Θ Shaft rotation amount Θm Target rotation amount BH Parts KB Board

Claims (2)

A nozzle shaft extending in the vertical direction, a nozzle attached to the lower end of the nozzle shaft, a motor, and a motor shaft that is spanned between the motor shaft that is the rotation axis of the motor and the nozzle shaft to rotate the motor shaft. A component mounting device for attaching a component to a board by adsorbing the component to the nozzle, the component mounting device comprising: a belt for transmitting a component to the nozzle shaft; and a control section for controlling rotation of the motor shaft;
After rotating the motor shaft in one direction to rotate the nozzle shaft, the control unit rotates the motor shaft in a direction opposite to the first direction so that tension remaining in the belt is reduced. A component mounting device that rotates in different directions. A nozzle shaft extending in the vertical direction, a nozzle attached to the lower end of the nozzle shaft, a motor, and a motor shaft that is spanned between the motor shaft that is the rotation axis of the motor and the nozzle shaft to rotate the motor shaft. A control method in a component mounting device for attaching a component to a substrate by adsorbing the component to the nozzle, the control method comprising: a belt for transmitting a component to the nozzle shaft;
After rotating the motor shaft in one direction to rotate the nozzle shaft, rotating the motor shaft in a return direction opposite to the first direction so that tension remaining in the belt is reduced. A control method for a component placement device.

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