Motor control device, mounting head, and control method for motor control device

Abstract

To provide a motor control device, a mounting head, and a control method for the motor control device that can perform appropriate control when a contact member moved by a stepping motor is brought into contact with a stopper.SOLUTION: A motor control device includes: a stepping motor, a contact member that moves in accordance with the rotation of the stepping motor; a stopper that comes into contact with the contact member to restrict the movement of the contact member; a driver circuit that drives the stepping motor to rotate on the basis of a pulse signal; and a control device that outputs a pulse signal of a first pulse frequency to the driver circuit to control the driver circuit when the contact member is in a non-contact state where it is not in contact with the stopper, and outputs a pulse signal of a second pulse frequency, which is a frequency different from the first pulse frequency, to the driver circuit to control the driver circuit when the contact member is in contact with the stopper.SELECTED DRAWING: Figure 10

Description

[Technical Field]

[0001] The present disclosure relates to rotation control of a stepping motor. [Background technology]

[0002] Various devices using a stepping motor as a drive source have been proposed. Patent Document 1 below describes a motor control device that uses a stepping motor to drive a valve of a refrigeration cycle device used in vehicle air conditioning. The motor control device executes an initialization process in which a shaft driven by the stepping motor hits the end of the shaft's movable range to update the origin position. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] Japanese Patent Application Publication No. 2019-221021 Summary of the Invention [Problem to be solved by the invention]

[0004] As in the above-mentioned Patent Document 1, when a member moved by a stepping motor is brought into contact with a stopper that restricts the movement to update the origin position, the vibration mode of the member changes when the moving member comes into contact with the stopper, which may result in the amplification of the vibration of the member.

[0005] The present disclosure has been made in consideration of such circumstances, and aims to provide a motor control device, a mounting head, and a control method for a motor control device that can perform appropriate control when a contact member moved by a stepping motor is brought into contact with a stopper. [Means for solving the problem]

[0006] This specification discloses a motor control device including a stepping motor, a contact member that moves in accordance with the rotation of the stepping motor, a stopper that comes into contact with the contact member and restricts the movement of the contact member, a driver circuit that drives the stepping motor to rotate based on a pulse signal, and a control device that outputs a pulse signal of a first pulse frequency to the driver circuit to control the driver circuit when the contact member is in a non-contact state where it is not in contact with the stopper, and outputs a pulse signal of a second pulse frequency that is different from the first pulse frequency to the driver circuit to control the driver circuit when the contact member is in contact with the stopper.

[0007] Furthermore, the contents disclosed in this specification are not limited to implementation as a motor control device, but are also extremely useful when implemented as a mounting head equipped with a motor control device and a control method for controlling a motor control device. [Effects of the Invention]

[0008] When the contact member comes into contact with the stopper, the vibration mode changes, and therefore the appropriate pulse frequency differs between the contact state and the non-contact state. According to the present disclosure, in the non-contact state, a pulse signal of a first pulse frequency is used to control the driver circuit, and in the contact state, a pulse signal of a second pulse frequency different from the first pulse frequency is used to control the driver circuit. As a result, appropriate control can be performed by using the first pulse frequency that matches the vibration mode in the non-contact state and the second pulse frequency that matches the vibration mode in the contact state. [Brief explanation of the drawings]

[0009] [Figure 1] 1 is a perspective view showing a portion of an electronic circuit component mounting line equipped with a plurality of mounting modules according to the present embodiment; [Figure 2] FIG. 2 is a perspective view showing a rotary type mounting head and a mounting head moving device of the mounting module. [Figure 3] FIG. [Figure 4] FIG. 3 is a perspective view showing a portion of the mounting head near a component mounting position. [Figure 5] FIG. 4 is a perspective view showing a portion of the mounting head near a component receiving position. [Figure 6] FIG. 2 is a side cross-sectional view schematically showing the mounting head. [Figure 7] FIG. 2 is a block diagram conceptually showing a control device of the mounting module. [Figure 8] FIG. 10 is a perspective view showing a return device provided at the output portion of the stepping motor. [Figure 9] FIG. 2 is a diagram showing the configuration of a module control computer, a mounting head control device, and a stepping motor control device. [Figure 10] FIG. 5 is a schematic diagram for explaining an origin return operation. [Figure 11] 6 is a graph showing the displacement of vibration generated in the detection member before and after the contact member comes into contact with the first stopper. [Figure 12] 6 is a graph for explaining the timing of switching the first pulse frequency. DETAILED DESCRIPTION OF THE INVENTION

[0010] An embodiment for implementing a motor control device according to the present disclosure will be described below with reference to the drawings. FIG. 1 shows a perspective view of a mounting module 10 equipped with a motor control device according to this embodiment. In the example shown in FIG. 1, two mounting modules 10 are arranged adjacent to each other in a row on a single base 12 to form a mounting line. For example, the configuration described in Japanese Patent Application Laid-Open No. 2004-104075 can be adopted as the mounting module 10. Therefore, in the following description, portions of the mounting module 10 that can adopt the configuration described in the above publication will be omitted as appropriate. In the following description, electronic circuit components will be abbreviated as components.

[0011] Each of the two mounting modules 10 includes a module body 18, a circuit board transport device 20, a circuit board holding device 22, a component supply device 24, a rotary mounting head (hereinafter simply referred to as the mounting head) 26, a mounting head moving device 28, a reference mark imaging device 30 (see FIG. 2), a component imaging device 32, and a module control device 34 (see FIG. 7). The circuit board transport device 20 includes, for example, two board conveyors 40, 42, and transports circuit boards (hereinafter simply referred to as boards) 44 in a direction parallel to the line-up of the two mounting modules 10 and horizontal to the installation surface of the mounting module 10. The circuit boards are, for example, printed wiring boards or printed circuit boards. A circuit board holding device 22 is provided on each of the two board conveyors 40, 42. Each of the two circuit board holding devices 22 has a support member (not shown) that supports the board 44 from below and clamp members that clamp both side edges of the board 44 that are parallel to the conveyance direction, and holds the board 44 in an orientation where the component mounting surface on which components are mounted is horizontal. In the following explanation, as shown in Figures 1 and 2, the conveyance direction of the board 44 is referred to as the X-axis direction, and the direction that is parallel to the component mounting surface of the board 44 held by the circuit board holding device 22 and perpendicular to the X-axis direction is referred to as the Y-axis direction. The component supply device 24 has a plurality of tape feeders 50 that are detachable from the front end of a base 52 of the mounting module 10 in the Y-axis direction and supply components.

[0012] As shown in FIG. 2, the mounting head moving device 28 includes an X-axis moving device 60 and a Y-axis moving device 62. The Y-axis moving device 62 is provided on the upper part of the module main body 18 and includes a linear motor 64 and a Y-axis slide 66. The linear motor 64 is provided across the component supply position of the component supply device 24 and the two circuit board holding devices 22 in the Y-axis direction, and moves the Y-axis slide 66 to any position in the Y-axis direction. The X-axis moving device 60 is attached to the Y-axis slide 66 and includes two X-axis slides 70 and 72 and an X-axis slide moving device 74. The X-axis slide moving device 74 moves each of the X-axis slides 70 and 72 in the X-axis direction. Note that FIG. 2 only illustrates the X-axis slide moving device 74, which moves the X-axis slide 72. The X-axis slides 70 and 72 are movable in the X-axis direction relative to the Y-axis slide 66 by being driven by the X-axis slide moving device 74, and are also movable relative to each other in the X-axis direction.

[0013] The two X-axis slide moving devices 74 each have, for example, an electric motor 76 and a feed screw mechanism 78 including a screw shaft and a nut, and move the X-axis slides 70, 72 to any position in the X-axis direction. For example, the X-axis slide 70 is movable in the X-axis direction on the Y-axis slide 66, and the X-axis slide 72 is movable in the X-axis direction on the X-axis slide 70. The electric motor 76 is, for example, a servo motor with an encoder. The feed screw mechanism is, for example, a ball screw mechanism. The mounting head 26 is detachable from the X-axis slide 72 and moves in the X-axis and Y-axis directions in conjunction with the movement of the X-axis slide 72, moving to any position within a movement range spanning the component supply position of the component supply device 24 and the two circuit board holding devices 22. The fiducial mark imaging device 30 is mounted on the X-axis slide 72 and moves together with the mounting head 26 to capture an image of a fiducial mark (not shown) provided on the board 44. 1 is provided at a position between the circuit board transport device 20 and the component supply device 24 on the base 52, and captures images of the components held by the mounting head 26 from below.

[0014] Next, we will explain the mounting head 26. For example, the configurations described in International Publication No. WO2014 / 136231, Japanese Patent Application Laid-Open No. 2013-69798, and International Publication No. WO2014 / 045377 can be used for the mounting head 26. Therefore, in the following explanation, when describing the rotary-type mounting head 26, explanations of parts that can adopt the configurations described in the above publications will be omitted as appropriate.

[0015] As shown in FIG. 3, the mounting head 26 is equipped with a plurality of suction nozzles 90. These suction nozzles 90 are held by a rotor 92. The rotor 92 is equipped with a shaft 94 and a nozzle holder 96, as shown schematically in FIG. 6. Both ends of the shaft 94 are supported by a head body 98 via bearings 100 and 102, and the shaft 94 is rotatably supported with its axis vertical. The rotor 92 is rotated by a rotor rotation device 104 around the vertical axis in both forward and reverse directions by any angle. The rotor rotation device 104 is driven by an electric motor 106 (see FIG. 3) provided in the head body 98, and the rotation of the electric motor 106 is transmitted to the rotor 92 via gears 108 and 110.

[0016] The nozzle holding portion 96 has a larger diameter than the shaft portion 94 and is provided with a plurality of (twelve in this embodiment) nozzle holders 120, allowing the rotor 92 to hold up to twelve suction nozzles 90. The twelve nozzle holders 120 are arranged on the outer periphery of the nozzle holding portion 96, on a circumference centered on the rotational axis of the rotor 92. The twelve nozzle holders 120 are respectively arranged at twelve positions on the circumference, at equal angular intervals (30-degree intervals), and are held in an orientation such that their axial directions are parallel to the rotational axis of the rotor 92, and are held so that they can advance and retreat in the axial direction (so that they can move up and down in the vertical direction in this embodiment). Furthermore, each of the twelve nozzle holders 120 is fitted to the rotor 92 so as to be rotatable about its own axis, and holds a suction nozzle 90.

[0017] The rotor 92 is rotated intermittently, for example, at angular intervals equal to the angular intervals at which the nozzle holders 120 are disposed. As a result, the twelve suction nozzles 90 revolve around the rotation axis of the rotor 92 and sequentially stop at each of the twelve rotation positions set at equal angular intervals. As shown in FIG. 3, the nozzle holder 120 is biased upward by a compression coil spring 122, and a roller 124 provided on the upper part thereof functions as a cam follower and moves along a cam surface 128 of a cam 126 fixed to the head main body 98. As a result, the suction nozzles 90 move up and down while revolving around the rotation axis of the rotor 92. The vertical distance between the suction nozzles 90 and the circuit board 44 held by the circuit board holding device 22 varies depending on the rotation position (stop position). For example, the pivot position with the shortest vertical distance is the component mounting position where components are mounted on board 44, and the pivot position with the longest vertical distance, which is 180 degrees away from the component mounting position, is the component imaging position. A component receiving position where components are received from bulk feeder 200 is set between the component mounting position and the component imaging position. The removal of components from tape feeder 50 by suction nozzle 90 and the placement of components removed from tape feeder 50 and the bulk feeder onto board 44 are both performed at the component mounting position, which is also the position where components are received from tape feeder 50. Note that the compression coil spring 122, roller 124, and cam 126 are not shown in FIG. 6.

[0018] 3, the head main body 98 is provided with a nozzle rotation drive device 140. The nozzle rotation drive device 140 drives an electric motor 142 to rotate the nozzle holder 120 about its axis, thereby rotating the suction nozzles 90. As shown in FIG. 6, the rotation of the electric motor 142 is transmitted to gears 144 attached to each of the twelve nozzle holders 120 via gears 146, 147, and 148, causing all twelve suction nozzles 90 to rotate simultaneously.

[0019] As shown in FIGS. 3 and 5, nozzle lifting devices 150, 152 are provided at portions of the head main body 98 corresponding to the component mounting position and the component receiving position, respectively. As shown in FIG. 3, the nozzle lifting device 150 at the component mounting position includes a lifting member 154, a feed screw mechanism 156, and an electric motor 158. The feed screw mechanism 156 has a feed screw 160 and a nut 162. The lifting member 154 is fixed to the nut 162, and as shown in FIG. 4, a roller 164 is attached to the rotor 92 side of the lifting member 154 so as to be rotatable about an axis perpendicular to the rotation axis of the rotor 92. When the feed screw 160 is rotated by the electric motor 158, the lifting member 154 is moved to any position in the vertical direction while being guided by a guide rod 166 (see FIG. 3).

[0020] As the lifting member 154 descends, the roller 164 abuts against the upper surface of a plate-shaped engaged portion 168 (see FIG. 4) provided on the nozzle holder 120, pressing the nozzle holder 120 down against the biasing force of the compression coil spring 122 and lowering the suction nozzle 90. When the lifting member 154 ascends, the nozzle holder 120 is allowed to rise by the biasing force of the compression coil spring 122, and the suction nozzle 90 rises. The nozzle lifting device 152 at the component receiving position is configured similarly to the nozzle lifting device 150, and as shown in FIG. 5, includes a lifting member 172, a feed screw mechanism 178 including a feed screw 174 and a nut 176, and an electric motor 180 (see FIG. 3). A roller (not shown) that engages with the engaged portion 168 is rotatably attached to the lifting member 172.

[0021] 3, a component imaging device 190 is provided at the component imaging position. A camera 192 of the component imaging device 190 captures an image of a component picked up from the tape feeder 50 or bulk feeder 200 by the suction nozzle 90 via a reflecting device (not shown).

[0022] As shown in Figure 5, a bulk feeder 200 is provided at a portion of the head main body 98 corresponding to the component receiving position, and the bulk feeder 200 moves together with the suction nozzle 90 and other components by the placement head moving device 28. Components are stored in a component case 210 of the bulk feeder 200 in a bulk pile. The bulk feeder 200 aligns the components stored in the component case 210 in a single line and supplies them. Note that the placement head 26 may not be configured to include the bulk feeder 200.

[0023] As shown in FIG. 4, the nozzle holding portion 96 of the rotor 92 is provided with a control valve device 280 corresponding to each of the twelve nozzle holders 120, which controls the supply of positive pressure and negative pressure to the suction nozzle 90. In this embodiment, the control valve device 280 is configured as a spool valve, and its valve spool 282 is fitted in a spool hole 284 formed in the nozzle holding portion 96 so as to be movable in a direction parallel to the rotational axis of the rotor 92, as shown schematically in FIG. 6. A small-diameter switching valve 285 of the valve spool 282 communicates with the suction nozzle 90 via a passage 286 formed in the nozzle holding portion 96 and a passage 288 formed in the nozzle holder 120. The states of the valve spool 282 shown in FIG. 6 are a positive pressure source connectable state in which the suction nozzle 90 is connectable to a positive pressure source 290 via the switching valve 285, and a negative pressure source connectable state in which the suction nozzle 90 is blocked from communication with a negative pressure source 292. When the valve spool 282 is lowered, the control valve device 280 changes from the positive pressure source communication enabled state and negative pressure source communication disabled state shown in Figure 6 to a positive pressure source communication disabled state in which the suction nozzle 90 is blocked from communication with the positive pressure source 290 and a negative pressure source communication enabled state in which the suction nozzle 90 is connectable to the negative pressure source 292 via the switching valve 285. When the valve spool 282 is raised, the control valve device 280 changes back to the opposite state. The control valve device 280 constitutes a negative pressure control valve and a positive pressure control valve, and in this embodiment, the negative pressure control valve and the positive pressure control valve are integrally configured. The negative pressure control valve and the positive pressure control valve may be provided separately.

[0024] As shown in FIG. 6 , a central hole 300 is formed within the rotor 92, with its axis as its centerline. One end of the central hole 300 opens to the upper surface of the shaft portion 94, and the other end is a bottomed hole that extends to the interior of the nozzle holder 96, with a support shaft 302 concentrically disposed within. The upper end of the support shaft 302 is fixed to the head body 98, and bearings 304, 306 are provided between the upper and lower ends and the rotor 92, so that the support shaft 302 does not rotate despite the rotation of the rotor 92. The diameter of the support shaft 302 is smaller than the diameter of the central hole 300. A communication control unit 310 having a diameter that can be fitted into the central hole 300 for relative rotation is integrally provided at the lower end of the support shaft 302, adjacent to the upper side of the portion where the bearing 306 is provided. As a result, an annular passage 312 is formed above the communication control unit 310 within the central bore 300, and a communication chamber 314 is formed below the communication control unit 310, between the support shaft 302 and the bottom surface of the central bore 300. The passage 312 is connected to the positive pressure source 290 via a port 320 formed in the shaft portion 94, an annular passage 322 provided in the head main body 98, a passage 324 connected to the passage 322, etc. The communication chamber 314 is also connected to the negative pressure source 292 via a passage 330 formed in the shaft portion 94 and a passage 332 formed in the head main body 98.

[0025] A plurality of (twelve in this embodiment) first radial passages 350 extending radially from the central hole 300 are formed in a portion of the nozzle holder 96 corresponding to the communication control section 310. Each of the twelve first radial passages 350 is perpendicular to each of the twelve spool holes 284 and extends at equal angular intervals to twelve positions corresponding to each of the twelve suction nozzles 90. Each of the twelve first radial passages 350 is connected to the suction nozzle 90 via a selector valve 285 and passages 286 and 288 when a control valve device 280 provided for the corresponding suction nozzle 90 is set to a positive pressure source connectable state.

[0026] Additionally, a plurality of second radial passages 352 (twelve in this embodiment) are formed within the nozzle holder 96, extending radially from the communication chamber 314. Each of the twelve second radial passages 352 is formed below the first radial passages 350, intersects each of the twelve spool holes 284 at right angles, and extends from the center of the rotor 92 to positions corresponding to each of the twelve suction nozzles 90 at equal angular intervals. Each of the twelve second radial passages 352 is connected to the negative pressure source 292 via the communication chamber 314 regardless of the rotational position of the rotor 92. Each of the twelve second radial passages 352 is connected to the suction nozzle 90 via a selector valve 285 and passages 286 and 288 when a control valve device 280 provided for the corresponding suction nozzle 90 is set to a negative pressure source connectable state.

[0027] A notch 360 that opens onto the outer circumferential surface of communication control unit 310 is formed in a portion of the outer periphery of communication control unit 310 corresponding to the portion where first radial passages 350 are formed. Notch 360 is in communication with passage 312 via passage 362 formed in the portion of communication control unit 310 that defines notch 360. By rotating the rotor 92 relative to the communication control unit 310 fixed to the head main body 98, the twelve first radial passages 350 rotate relative to the notches 360. Of the twelve first radial passages 350, the first radial passages 350 arranged at positions corresponding to the notches 360 communicate with the notches 360. As shown in International Publication WO 2014 / 136231, for example, the notches 360 are formed as notches having an arch-shaped cross section defined by a chord corresponding to a central angle of 120° of the rotor 92 and the circumference when viewed in the axial direction. Furthermore, the notches 360 are positioned so that the center of the notch 360 aligns with the opening of the rotor center side of one of the first radial passages 350 corresponding to the suction nozzle 90 arranged at the component mounting position. In this case, the first radial passages 350 on either side of the first radial passage 350 at the component placement position are also fully open via the notches 360. Furthermore, the openings of the first radial passages 350 on either side of the first radial passages 350 are partially closed by the communication control unit 310. Therefore, the air flow through the first radial passages 350 is changed depending on the rotational position relative to the notches 360. The shape of the notches 360 described above is merely an example. For example, the notches 360 may be configured to fully open only the first radial passages 350 corresponding to the suction nozzles 90 at the component placement position. Furthermore, the portion of the communication control unit 310 without the notches functions as a blocking unit 396 that blocks the first radial passages 350. For example, the first radial passage 350 corresponding to the suction nozzle 90 at the component receiving position is fully closed.

[0028] Valve switching devices 370, 372 are provided at portions of the head body 98 corresponding to the component mounting position and the component receiving position, respectively. As shown in FIG. 4, the valve switching device 370 provided at the component mounting position includes a switching member 374 and a switching member drive device 376. The switching member drive device 376 is driven by a stepping motor 378 (see FIG. 7), and rotates the switching member 374 in both forward and reverse directions about an axis perpendicular to the rotational axis of the rotor 92. This causes two engaging portions 380, 382 formed by rollers of the switching member 374 to selectively engage with a plate-shaped engaged portion 384 of the valve spool 282, thereby lowering or raising the valve spool 282 relative to the nozzle holder 96. The switching member 374 and other components will be described in detail below.

[0029] As shown in FIG. 5, the valve switching device 372 provided at the component receiving position includes a switching member 390 and a switching member drive device 392. The switching member drive device 392 includes, for example, an air cylinder 394 (see FIG. 7) and raises and lowers the switching member 390. A roller (not shown) is rotatably attached to the switching member 390 around an axis perpendicular to the rotation axis of the rotor 92 to form an engaging portion. The roller engages with the upper surface of the engaged portion 384 and presses down the valve spool 282. As a result, at the component receiving position, the valve spool 282 switches the switching valve 285 from a state in which a positive pressure source is connectable to a state in which a negative pressure source is connectable, thereby supplying components from the bulk feeder 200 to the suction nozzle 90. The drive source of the switching member drive device 392 is not limited to the air cylinder 394, but may be another fluid pressure cylinder such as a hydraulic cylinder. The drive source of the switching member drive device 392 may also be a motor such as a stepping motor. Therefore, the origin return operation of the valve switching device 370, which will be described later, may be performed by the valve switching device 372 at the part receiving position.

[0030] As shown in FIG. 7, the head main body 98 is provided with a mounting head control device 400. The mounting head control device 400 is mainly composed of a mounting head control computer 402. The mounting head control device 400 is connected to a module control computer 404, which is the main component of the module control device 34. The mounting head control device 400 controls the electric motor 106, which is a servo motor with an encoder. In FIG. 7, only the encoder 406 of the electric motor 106 is shown. The mounting head control device 400 also controls the stepping motor 378 and the air cylinder 394. A sensor 507 of a return device 501 (see FIG. 8), which will be described later, is also connected to the mounting head control device 400.

[0031] The module control device 34 also controls the drive sources of the various devices constituting the placement module 10, such as the linear motor 64, via a drive circuit 420. The input / output interface of the module control computer 404 is connected to an image processing computer 430 that processes data obtained by imaging with the fiducial mark imaging device 30 and the component imaging device 32, encoders 432 (one of which is shown in FIG. 7 as a representative) provided on the electric motors 76 and the like of the X-axis slide moving device 74, the placement head control computer 402, and the like. The image data captured by the component imaging device 190 of the placement head 26 is sent to the image processing computer 430 for processing, and the necessary data is sent to the placement head control computer 402. The RAM of the module control computer 404 also stores various programs and data for placing components on the board 44.

[0032] In the placement module 10 configured as described above, one mode of component placement on a board 44 is for the suction nozzles 90 to pick up components from the bulk feeder 200 or tape feeder 50 and place them on one board 44. The 12 suction nozzles 90 are sequentially rotated to their component receiving positions by the rotation of the rotor 92, receive components from the bulk feeder 200 or the like, are imaged by the component imaging device 190 at their component imaging positions, and are then rotated to their component placement positions to place the components on the board 44. During placement, any errors in the component holding position by the suction nozzles 90 and in the position of the component placement location on the board 44 obtained by imaging the reference marks are corrected. While the placement head 26 is moved relative to the circuit board holding device 22, the rotation of the rotor 92 sequentially moves the 12 suction nozzles 90 to their respective rotation positions, where component reception, imaging, and placement are carried out simultaneously.

[0033] When a suction nozzle 90 that has picked up a component is rotated to the component-mounting position, the control valve device 280 corresponding to that suction nozzle 90 is set to a negative pressure source communication state, and negative pressure is supplied to the suction nozzle 90. For example, the first radial passages 350 at the rotation position two positions before the component-mounting position in the rotor rotation direction are set to a half-open state by the notch 360, and communication with the positive pressure source 290 begins. However, because the control valve device 280 corresponding to this first radial passage 350 is set to a negative pressure source communication state, positive pressure is not supplied to the suction nozzle 90, and the suction nozzle 90 remains holding the component. At the rotation position one position before the component-mounting position, the first radial passages 350 change from a half-open state to a fully open state, but because the first radial passages 350 are set to a negative pressure source communication state, positive pressure is not supplied to the suction nozzle 90.

[0034] As shown in FIG. 4 , the engaging portion 168 of the nozzle holder 120 is long in the direction of rotation of the suction nozzle 90. Before the suction nozzle 90 reaches the component placement position, the lifting member 154 of the nozzle lifting device 150 is lowered to engage with the engaging portion 168, lowering the suction nozzle 90 in parallel with its rotation. The lifting member 154 engages the engaging portion 168 at the roller 164, allowing the suction nozzle 90 to rotate as the roller 164 rotates. The valve switching device 370, under the control of the placement head control device 400, operates in parallel with the descent of the suction nozzle 90, pushing up the valve spool 282 with the switching member 374 and switching the control valve device 280 from a state in which negative pressure can be communicated to a state in which positive pressure can be communicated. This disconnects the suction nozzle 90 from the negative pressure source 292 and connects it to the positive pressure source 290. The supply of positive pressure releases the component, allowing it to be placed on the board 44.

[0035] The engaged portion 384 of the valve spool 282 is formed in a plate shape with a predetermined width in the direction of rotation of the valve spool 282. The valve switching device 370 drives the stepping motor 378 under the control of the placement head control device 400 to raise the switching member 374 and engage the engaging portion 382, ​​which is a roller, with the engaged portion 384 of the valve spool 282. The valve spool 282 is pushed up while rotating together with the suction nozzle 90 due to engagement and rotation with the engaging portion 382. After the component is placed, the suction nozzle 90 is raised and rotated. The valve switching device 370 drives the stepping motor 378 to switch the control valve device 280 using the switching member 374, and then returns the switching member 374 to a position where the control valve device 280 will be switched to correspond to the next suction nozzle 90 that will arrive at the component placement position. In this manner, the valve switching device 370 drives the stepping motor 378 to move the switching member 374, thereby switching the engaged portion 384 (switching valve 285). The above-described operation of the valve switching device 370 is merely an example. For example, if the control valve device 280 is configured to release a component by depressing the engaged portion 384, the valve switching device 370 may lower the switching member 374 at the component mounting position and cause the engaging portion 380 to depress the engaged portion 384. Furthermore, the switching of the engaged portion 384 by the valve switching device 372 at the component receiving position is performed in the same manner as the valve switching device 370, and therefore a description thereof will be omitted. In this manner, the placement module 10 receives and places components in parallel, and the control valve device 280 is switched in parallel with the descent of the suction nozzle 90, thereby achieving high placement efficiency.

[0036] (Regarding origin return operation) Next, the origin return operation will be described. Fig. 8 shows a perspective view of a return device 501 provided at the output portion of the stepping motor 378. The stepping motor 378 has a main body attached to a metal plate 513 shown in Fig. 8, and is fixed to the mounting head 26 via the metal plate 513. The output shaft 378A of the stepping motor 378 is a cylindrical metal member, and protrudes from a through-hole 513A formed in the metal plate 513 toward the front side in Fig. 8.

[0037] Here, for example, the mounting head control device 400 causes the stepping motor 378 of the valve switching device 370 to perform a return-to-origin operation when the mounting head 26 is started. The return-to-origin operation is an operation in which, after the stepping motor 378 is started, the switching member 374 (engagement portions 380, 382) is aligned with the origin position, which serves as a reference for the operation of raising or lowering the valve spool 282. FIG. 8 shows a state in which the switching member 374 is located at the origin position (hereinafter referred to as the origin-returned state). For example, the mounting head control device 400 initiates the return-to-origin operation based on an instruction from the module control computer 404 after the mounting module 10 is powered on, power is supplied to the mounting head 26, and the mounting head 26 is started. Alternatively, for example, the mounting head control device 400 initiates the return-to-origin operation based on an instruction from the module control computer 404 after the mounting head 26 is replaced, a new mounting head 26 is attached to the X-axis slide 72, and the mounting head 26 is started.

[0038] The mounting head 26 is configured to be detachable from the X-axis slide 72. Therefore, the rotational position of the output shaft 378A of the stepping motor 378 may change during storage or transportation of the mounting head 26. Alternatively, even if the mounting head 26 remains attached to the X-axis slide 72, if the mounting module 10 is powered off and no power is supplied to the stepping motor 378, the rotational position of the output shaft 378A may change if some vibration or other condition occurs in the mounting head 26. If the rotational position of the output shaft 378A changes, the origin position when the valve switching device 370 starts the switching operation of the valve spool 282 shifts. As a result, the valve spool 282 may not switch properly, or the stepping motor 378 may lose synchronization. Therefore, the mounting head control device 400 executes a return-to-origin operation before starting the switching of the valve spool 282.

[0039] As shown in FIGS. 4 and 8 , a switching member 374 is attached to the tip of the output shaft 378A. The switching member 374 is attached to the output shaft 378A via a holding member 375. The holding member 375 is a metal member, and the switching member 374 is attached to a tip portion of the output shaft 378A in the axial direction with a bolt 377. The base end portion of the holding member 375 is attached to a bracket 503 of a return device 501 (described later). The switching member 374 is a plate-like member that has a predetermined thickness in the axial direction of the output shaft 378A, extends in a direction perpendicular to the output shaft 378A, and is substantially rectangular in axial view. The axial direction of the output shaft 378A is perpendicular to the plane of the switching member 374. The switching member 374 is provided at a position close to the output shaft 378A and rotates in the rotational direction of the output shaft 378A as the output shaft 378A rotates. The engaging portions 380, 382 are rollers provided at both ends of the switching member 374 in the longitudinal direction and rotatably mounted relative to the switching member 374. The engaging portions 380, 382 are attached to the outer surface of the switching member 374 in the axial direction of the output shaft 378A. For example, in the home position return state, the switching member 374 is aligned in the up-down direction. The engaging portion 380 is positioned diagonally above and to the right of the output shaft 378A in FIG. 8, and the engaging portion 382 is positioned diagonally below and to the right of the output shaft 378A. The engaging portions 380, 382 rotate together with the switching member 374, moving the engaged portion 384 and the valve spool 282 at the component mounting position.

[0040] The return device 501 is a device for performing a return-to-origin operation and includes a bracket 503, a detected member 505, a sensor 507, a contact member 509, a first stopper 510, and a second stopper 511. The bracket 503 is a portion that protrudes from the through-hole 513A of the output shaft 378A and is attached to the base end side of the switching member 374. The bracket 503 is made up of, for example, multiple metal members, and the multiple metal members are fixed by bolts 503A with the output shaft 378A sandwiched between the multiple metal members. The bracket 503 rotates integrally with the output shaft 378A. The detected member 505 is a rectangular thin metal plate and is attached to the bracket 503. The detected member 505 extends radially outward from the bracket 503, i.e., in a direction perpendicular to the axial direction of the output shaft 378A. Similar to the switching member 374, the detected member 505 and the contact member 509 rotate in accordance with the rotation of the output shaft 378A. Therefore, the switching member 374, the detected member 505, and the contact member 509 each have their own origin position, and in the origin return state, each member is located at its origin position. In the following description, the origin positions of these members will be collectively referred to as the origin position.

[0041] The sensor 507 is a device for detecting the detected member 505 when the detected member 505 is located at the origin position in the rotation direction, and is electrically connected to the mounting head control device 400. The sensor 507 is, for example, a proximity sensor, and outputs a low-level signal to the mounting head control device 400 when the detected member 505 is not located at the origin position, and outputs a high-level signal to the mounting head control device 400 when the detected member 505 is located at the origin position. Note that the sensor 507 is not limited to a proximity sensor, and may be another type of sensor, such as an optical sensor. Furthermore, the sensor 507 is not limited to a non-contact sensor, and may be a contact sensor, such as a relay switch that turns on / off by coming into contact with the rotating detected member 505.

[0042] 8, in the origin return state, when the output shaft 378A is viewed from the tip end, the detected member 505 is disposed in parallel with the switching member 374, extends downward from the output shaft 378A (towards 6 o'clock), and is disposed in the detection area of ​​the sensor 507. By performing the origin return operation, the mounting head control device 400 can determine whether the rotational position of the output shaft 378A has been aligned with the position shown in FIG. 8 based on whether the detected member 505 has been detected by the sensor 507.

[0043] Contact member 509 is a rectangular, thin metal plate with a tapered tip, and is attached to bracket 503. Like detected member 505, contact member 509 extends radially outward from bracket 503 and rotates with the rotation of output shaft 378A. Contact member 509 extends outward in the axial direction from a position behind switching member 374. In the origin return state, contact member 509 extends in a direction perpendicular to detected member 505 and is disposed along the 3 o'clock direction when output shaft 378A is viewed from the tip side.

[0044] The first and second stoppers 510 and 511 come into contact with the contact member 509, which moves in the rotational direction, and restrict the movement of the contact member 509. Each of the first and second stoppers 510 and 511 is, for example, a cylindrical metal member attached to a metal plate 513 and extending in a direction parallel to the output shaft 378A (toward the front side in FIG. 8). In the configuration shown in FIG. 8, the first stopper 510 is disposed at approximately 4 o'clock when viewed from the tip end side of the output shaft 378A, and the second stopper 511 is disposed at approximately 1 o'clock. In other words, the rotation range of the contact member 509 is limited to the range between the first and second stoppers 510 and 511. Furthermore, the output shaft 378A and the detection target member 505 rotate together with the contact member 509, and therefore rotate within the same rotation range.

[0045] The above-described configuration of the returning device 501 is an example. For example, the returning device 501 may not include the detected member 505. In this case, the sensor 507 may be disposed in a position where it can detect the rotational position of the contact member 509. The positions of the contact member 509 and the detected member 505 may be interchanged. The switching member 374 may be attached to the contact member 509. The output shaft 378A may be a rectangular prism. The returning device 501 may not include the second stopper 511.

[0046] FIG. 9 shows the control configuration of the module control computer 404, the mounting head control device 400, and the stepping motor 378. As shown in FIG. 9, the mounting head control device 400 includes a driver circuit 407 in addition to a mounting head control computer 402. The stepping motor 378 is, for example, a two-phase excitation stepping motor having windings corresponding to the A-phase and B-phase layers on the stator. The driver circuit 407 is connected to the windings of the stepping motor 378 and changes the current flowing through the windings based on a pulse signal PS input from the mounting head control computer 402. The mounting head control computer 402 controls the stepping motor 378 via the driver circuit 407 by changing the supply or non-supply of the pulse signal PS, the number of pulses, the pulse frequency, etc. The mounting head control computer 402 can control the rotation angle, rotation speed, rotation direction, etc. of the stepping motor 378 by changing the pulse signal PS. Note that the stepping motor 378 is not limited to a two-phase excitation motor, and may be a motor with other numbers of phases, such as three phases. The stepping motor 378 may be of various types such as PM, HB, or VR types.

[0047] FIG. 10 schematically illustrates the state of the return device 501 during the origin return operation. Note that FIG. 10 does not illustrate the second stopper 511. The state of step (hereinafter simply referred to as S) 11 in FIG. 10 illustrates the state before the origin return operation begins. In the following explanation, the rotational positions of the output shaft 378A, the contact member 509, and the detected member 505 before the origin return operation begins are referred to as the initial positions. Furthermore, the output shaft 378A, the contact member 509, and the detected member 505 rotate integrally. Therefore, to avoid complication of explanation, the following explanation will mainly focus on the rotational position of the contact member 509, and will omit explanations of the rotational positions of the other members as appropriate. The initial position indicated by the solid line in S11 indicates the rotational positions of the contact member 509 and the detected member 505 in the origin return state. For example, when the mounting head control device 400 has finished controlling all stepping motors 378, such as for mounting operations, it returns the contact member 509 to the origin position. Therefore, unless the rotational position is shifted due to some influence, the initial position will be the origin position. However, as described above, the rotational positions of the contact member 509 and the detected member 505 may be shifted due to vibration or the like while the power is off. As shown by the dashed lines in S11, the initial positions are the rotational positions of the contact member 509A and the detected member 505A shifted clockwise from the origin position, and the rotational positions of the contact member 509B and the detected member 505B shifted counterclockwise.

[0048] For example, when the placement head 26 is attached to the X-axis slide 72 and power is supplied to start the placement head control device 400, the placement head control device 400 begins communication with the module control computer 404. When the module control computer 404 detects through communication with the placement head control device 400 that the placement head 26 has been connected, it instructs the placement head control device 400 to begin a return-to-origin operation. When the placement head control device 400 receives the start instruction from the module control computer 404, it rotates the contact member 509 clockwise as shown in S13.

[0049] FIG. 11 shows the displacement of vibration generated in the detected member 505 before and after the contact member 509 comes into contact with the first stopper 510. The vertical axis represents the vibration generated in the detected member 505; for example, displacement is measured by directing a laser from a laser displacement meter at the side of the detected member 505 during a return-to-origin operation. The vertical axis also represents the clockwise direction toward the first stopper 510 as the negative direction and the counterclockwise direction toward the second stopper 511 as the positive direction. The contact member 509 is fixed to the output shaft 378A by the same bracket 503 as the detected member 505. Therefore, the contact member 509 generates vibration similar to that of the detected member 505. The horizontal axis in FIG. 11 represents elapsed time.

[0050] In S13, the mounting head control device 400 rotates the contact member 509 in the clockwise direction (negative direction) by a first pulse number n1 at a predetermined first pulse frequency f1. The first pulse frequency f1 is, for example, 55 Hz (pps). The first pulse number n1 is, for example, 52 pulses. This first pulse number n1 is the number of pulses required to rotate the contact member 509 at the first pulse frequency f1 from the origin position to the position where it contacts the first stopper 510. In other words, the first pulse number n1 is the number of pulses required to move the contact member 509 from the initial position to the first stopper 510 when there is no deviation from the initial position and the initial position is the origin position. The first pulse number n1 is also the number of pulses required for the contact member 509 to go from a non-contact state where it is not in contact with the first stopper 510 to a contact state where it is in contact with the first stopper 510.

[0051] After executing S13, the mounting head control device 400 changes the pulse frequency from the first pulse frequency f1 to the second pulse frequency f2 and rotates the contact member 509 clockwise by the second pulse number n2 at the second pulse frequency f2 (S15). The second pulse frequency f2 is, for example, 65 Hz. The second pulse number n2 is, for example, several pulses or a dozen or so pulses. This second pulse number n2 is the number of pulses that rotates the contact member 509 toward the first stopper 510 when the contact member 509 is in contact with the first stopper 510. Therefore, if there is no deviation from the initial position, the contact member 509 rotates by the first pulse number n1 at the first pulse frequency f1 and contacts the first stopper 510, and then contacts (collides with) the first stopper 510 by the second pulse number n2 at the second pulse frequency f2. In other words, the first pulse number n1 is set so that the frequency switches from the first pulse frequency f1 to the second pulse frequency f2 before and after the contact member 509 comes into contact with the first stopper 510 if there is no deviation from the initial position.

[0052] In the origin return operation, as shown in S17 and subsequent steps described below, the contact member 509 is placed at the origin position based on the position where the contact member 509 abuts the first stopper 510. For this reason, in S13, it is preferable to bring the contact member 509 into contact with the first stopper 510. However, as shown by contact member 509B in S11, the initial position may be a position displaced counterclockwise from the origin position. For this reason, the second pulse number n2 is preferably a pulse number sufficient to reliably bring the contact member 509 into contact with the first stopper 510 when the contact member 509 does not reach the first stopper 510 even after rotating by the first pulse number n1. In other words, as shown by contact member 509B, it is preferable to set the second pulse number n2 to the number of pulses required to move the contact member 509 at the second pulse frequency f2 by the amount of deviation that may result in counterclockwise deviation from the origin position. For example, the second pulse number n2 is the number of pulses required to rotate at the second pulse frequency f2 from the origin position to the second stopper 511. As a result, the number of pulses required to rotate by the maximum amount of physical deviation that may occur is set as the second pulse number n2, and the contact member 509 can be reliably brought into contact with the first stopper 510.

[0053] The above-described set values ​​for the first number of pulses n1 and the second number of pulses n2 are merely examples. For example, the second number of pulses n2 may be set to the result of a positional deviation test. For example, vibration or the like may be applied to the mounting head 26 to measure the maximum or average amount of deviation from the origin position in the counterclockwise direction, and the second number of pulses n2 may be set to the number of pulses required to rotate the mounting head 26 by the measured amount of deviation at the second pulse frequency f2. Similarly, as shown in S11, the average amount of deviation from the origin position in the clockwise direction may be measured, and the first number of pulses n1 may be set to the number of pulses required to move the mounting head 26 from a position approaching the first stopper 510 by the measured amount of deviation to the first stopper 510 at the first pulse frequency f1. In this case, the second number of pulses n2 may be increased by the amount that the first number of pulses n1 is decreased. Furthermore, if the mounting head 26 performs the origin return operation multiple times after powering on, the number of pulses may be changed for each execution, such as the first or second execution.

[0054] Here, the mounting module 10 performs high-speed mounting, for example, at tens of thousands or hundreds of thousands of CPH (chips per hour), and switches the switching valve 285 every tens of milliseconds. However, if the origin return operation is performed at such a high speed, the reaction force when the contact member 509 collides with the first stopper 510 may become large, causing the contact member 509 to bounce back in the counterclockwise direction, which may result in loss of synchronization. For this reason, it is preferable to operate the contact member 509 in the origin return operation at a speed that is significantly slower than the rotational speed during the mounting operation.

[0055] On the other hand, if the switching period of the pulse signal PS is lengthened in order to slow the rotational speed of the contact member 509, a phenomenon occurs in which vibrations generated in the contact member 509 become larger. When large vibrations are generated in the contact member 509, depending on the switching timing of the pulse signal PS, a phenomenon may occur in which the contact member 509 swings significantly in the direction opposite to the desired direction of movement (clockwise or counterclockwise), or the contact member 509 rotates excessively in the direction of movement. The desired direction of movement here refers to the rotational direction in which the contact member 509 is desired to move based on the pulse signal PS from the mounting head control device 400. In this embodiment, the first and second pulse frequencies f1 and f2 are set so as to prevent such abnormal movement from occurring.

[0056] Specifically, FIG. 12 shows the timing of switching the first pulse frequency f1. The vertical axis, like FIG. 11, indicates the vibration generated in the detection target member 505 (contact member 509). The horizontal axis indicates elapsed time. The upper part of the graph in FIG. 12 shows the currents applied to the A-phase and B-phase windings of the stepping motor 378. At time T0 shown in FIG. 12, the A-phase and B-phase currents are not switched, and rotation is stopped. Next, starting at time T1, a pulse signal PS of the first pulse frequency f1 is output from the mounting head control computer 402 to the driver circuit 407, causing the contact member 509 (output shaft 378A) to rotate clockwise (negative displacement direction). The currents for each phase are switched at times T2, T3, T4, and T5. As shown in FIG. 12, vibration occurs in the contact member 509 relative to the target position during movement in the negative direction.

[0057] The first pulse frequency f1 is preset to a frequency that matches the vibration direction of the vibration (natural vibration) generated in the contact member 509. For example, the first pulse frequency f1 is set to a frequency at which the pulse switches when the contact member 509 vibrates in the direction opposite to the desired direction of travel of the contact member 509 in response to the rotation of the stepping motor 378. For example, as shown at time T2, the A-phase and B-phase currents (excitation phases) switch, i.e., the pulse switches, when the contact member 509 vibrates in the positive direction, which is opposite to the negative direction of travel. Similarly, at other times T3, T4, and T5, the pulse switches when the contact member 509 vibrates in the positive direction. By using the first pulse frequency f1 that switches at such timings, the vibration in the direction opposite to the direction of travel can be suppressed by the pulse switching. As shown in FIG. 12, from time T2 to time T5, the positive vibration (amplitude) that occurred immediately before those times is reduced by the pulse switching. By slowing down the rotation speed, vibrations occurring in the contact member 509 can be suppressed.

[0058] Note that the first pulse frequency f1 is not limited to the frequency that switches at the timing described above. For example, the first pulse frequency f1 may be a frequency at which the pulse switches (the current switches) at the timing when the vibration direction changes from the desired forward direction of the contact member 509 to the opposite direction in response to the rotation of the stepping motor 378. Specifically, in the example shown in FIG. 12, the frequency at which the pulse switches at the peak where the vibration wave indicated by the solid line switches from the negative direction to the positive direction (from downward to upward) may be adopted as the first pulse frequency f1. In this case, as in the above case, the vibration in the opposite direction can be suppressed by switching the pulse.

[0059] Furthermore, the manner of vibration generated in the contact member 509 changes between the contact state of S15 in which the contact member 509 is in contact with (collides with) the first stopper 510 and the non-contact state of S13. For this reason, if the contact member 509 is operated at the first pulse frequency f1 even in the contact state, the vibration of the contact member 509 and the rebound from the first stopper 510 will increase, which may cause loss of synchronization. Therefore, in this embodiment, different pulse frequencies are set for the contact state and the non-contact state, and appropriate pulse frequencies (rotational speeds) are set for each vibration state.

[0060] Specifically, the second pulse frequency f1 is set to a frequency that matches the vibration direction of the vibration generated in the contact member 509, and a frequency is set at which the pulse is switched (the excitation phase of the current is switched) at the timing when the contact member 509 is vibrating in the desired direction of movement. The vibration generated in the contact member 509 here refers to, for example, the vibration generated in the contact member 509 in a contact state where the contact member 509 is colliding with the first stopper 510. As a result, by switching the pulse while the contact member 509 is vibrating toward the first stopper 510, it is possible to suppress the reaction generated in the contact member 509 due to the collision with the first stopper 510 and to suppress the amplification of the vibration of the contact member 509 in the direction away from the first stopper 510. As a result, it is possible to suppress the occurrence of step-out, and to position the contact member 509 with respect to the first stopper 510.

[0061] The second pulse frequency f2 is not limited to the frequency that switches at the timing described above. For example, the second pulse frequency f2 may be a frequency at which the pulse switches (the current switches) at the timing when the vibration direction changes from the opposite direction to the desired traveling direction of the contact member 509 to the traveling direction in response to the rotation of the stepping motor 378. Specifically, the frequency at which the pulse switches at the peak where the vibration wave generated in the contact member 509 switches from the positive direction to the negative direction may be adopted as the second pulse frequency f2. In this case, as in the above case, the reaction of the collision can be suppressed and the vibration can be suppressed by switching the pulse.

[0062] As described above, in this embodiment, the second pulse frequency f2 is a higher frequency (65 Hz) than the first pulse frequency f1 (55 Hz). By setting frequencies in this relationship, it is possible to set pulse frequencies suitable for both the contact state and the non-contact state. Note that the natural frequency generated in the contact member 509 changes depending on the configuration of the return device 501 and the stepping motor 378. For this reason, the second pulse frequency f2 may be set to a frequency lower than the first pulse frequency f1 depending on the vibration mode generated in the contact member 509.

[0063] In S13, the mounting head control device 400 controls the driver circuit 407 by a first pulse count n1 using a pulse signal PS with a first pulse frequency f1, and then starts S15. The first pulse count n1 is the number of pulses required to move the contact member 509 from a preset origin position to a position where it contacts the first stopper 510 at the first pulse frequency f1. By setting the first pulse count n1 and the second pulse count n2 assuming a state where the initial position is the origin position, i.e., a state where no misalignment occurs, the pulse frequency can be switched in accordance with the transition from the non-contact state to the contact state when no misalignment occurs. Even if the initial position of the contact member 509 is misaligned, a certain amount of time can be secured to move the contact member 509 toward the first stopper 510 using the second pulse frequency f2, which can suppress vibration, and the contact member 509 can be positioned at the first stopper 510. As a result, the origin return can be performed appropriately.

[0064] The return device 501 may also include a sensor that detects contact between the first stopper 510 and the contact member 509. The sensor may be an optical sensor that detects when the contact member 509 has moved to a position where it contacts the first stopper 510, or a sensor that detects the impact of a collision that occurs on the first stopper 510. The mounting head control device 400 may then switch from the first pulse frequency f1 to the second pulse frequency f2 at the timing when the sensor detects contact. In this case, it is not necessary to set the first pulse number n1.

[0065] Furthermore, in this embodiment, contact member 509 is attached to output shaft 378A of stepping motor 378 and rotates together with output shaft 378A. First stopper 510 is a member that restricts movement of contact member 509 in the rotational direction. In a configuration in which contact member 509 is directly attached to output shaft 378A, there is a high possibility that vibrations generated in contact member 509 will increase due to a slower rotational speed. Therefore, in this direct attachment configuration, switching the pulse frequency between the contact state and the non-contact state described above is extremely effective in suppressing vibrations.

[0066] The contact member 509 does not have to be directly attached to the output shaft 378A. For example, a rack gear may be provided on the contact member 509, and a gear attached to the output shaft 378A may move the rack gear to slide the contact member 509 up and down. Alternatively, the output shaft 378A and the contact member 509 may be connected by a ball screw mechanism, and the contact member 509 may slide up and down in response to the rotation of the output shaft 378A. In this case, first and second stoppers 510 and 511 may be provided at positions that restrict the sliding movement of the contact member 509. Even in such an indirect connection, vibrations may be transmitted from the output shaft 378A to the contact member 509, causing it to vibrate. Therefore, even in this configuration, switching the pulse frequency depending on the contact state or non-contact state is effective. Furthermore, the movement direction of the contact member 509 in the present disclosure is not limited to the rotational direction, and it may also be a sliding direction.

[0067] As shown in FIGS. 10 and 11 , in S15, the mounting head control device 400 rotates the contact member 509 by the second pulse number n2 at the second pulse frequency f2, and then stops the rotation of the contact member 509 for a predetermined wait time. For example, the mounting head control device 400 stops the output of the pulse signal PS and stops the driver circuit 407 from switching the current (excitation phase). This wait time is the time required to suppress vibration of the contact member 509 before changing the rotation direction, and is the time required from the time the pulse switching is stopped until the vibration generated in the contact member 509 becomes extremely small or disappears. The wait time is, for example, 100 ms. By stopping the rotation of the stepping motor 378, the contact member 509 maintains its rotational position and vibration is suppressed. As a result, the contact member 509 is positioned at a position where it contacts the first stopper 510 in the clockwise direction.

[0068] Next, the mounting head control device 400 changes the pulse signal PS to reverse the rotation direction of the stepping motor 378 (counterclockwise), and rotates the contact member 509 by a predetermined third pulse number n3 at the first pulse frequency f1 (S17). Next, similar to after executing S15, the mounting head control device 400 executes S17 to rotate the contact member 509 in the counterclockwise direction at the first pulse frequency f1 by the third pulse number n3, and then stops the rotation of the contact member 509 for a predetermined wait time (e.g., 100 ms). This makes it possible to suppress vibration of the contact member 509 before changing the rotation direction.

[0069] The mounting head control device 400 then changes the pulse signal PS to change the rotation direction of the stepping motor 378 to the reverse direction (clockwise), and rotates the contact member 509 by a predetermined fourth pulse number n4 at the first pulse frequency f1 (S19). This allows the detection target member 505 to return to a position where it can be detected by the sensor 507, i.e., to the origin position. The mounting head control device 400 can appropriately switch the valve spool 282 based on the origin position.

[0070] Therefore, the third number of pulses n3 and the fourth number of pulses n4 are the numbers of pulses required to rotate the contact member 509 from the position where it is positioned by the first stopper 510 to the origin position. Specifically, for example, the third number of pulses n3 is 25 pulses, and the fourth number of pulses n4 is 7 pulses. In this case, the origin position is the position where the contact member 509 is rotated counterclockwise by 25 pulses from the first stopper 510 and then rotated clockwise by 7 pulses. In this way, the mounting head 26 of this embodiment can suppress vibration of the contact member 509 and properly perform origin return by switching the pulse frequency.

[0071] As described above, the mounting head control device 400 first controls the driver circuit 407 with the pulse signal PS of the first pulse frequency f1 to move the contact member 509 toward the first stopper 510 (S13). Next, in S15, the mounting head control device 400 controls the driver circuit 407 with the second pulse frequency f2 to move the contact member 509 toward the first stopper 510 (S15). Next, the mounting head control device 400 switches the rotation direction, moves the contact member 509 counterclockwise away from the first stopper 510, and moves the contact member 509 by the third pulse number n3 with the pulse signal PS of the first pulse frequency f1 (S17). Then, the mounting head control device 400 switches the rotation direction, rotates the contact member 509 clockwise, and rotates it by the fourth pulse number n4 at the first pulse frequency f1, returning it to the origin (S19). As a result, by setting an appropriate number of pulses as the difference between the third number of pulses n3 and the fourth number of pulses n4, the contact member 509 can be returned to the origin simply by rotating it by a predetermined number of pulses from a state in which it is positioned on the first stopper 510.

[0072] In the control of the origin return operation described above, in S17, the contact member 509 is rotated counterclockwise past the origin position, and then in S19, the contact member 509 is rotated clockwise to align with the origin position. Here, even if the contact member 509 is rotated counterclockwise by (n3-n4) pulses (18 pulses) in S15, the contact member 509 can still be aligned with the origin position, eliminating S19. However, eliminating S19 could, for example, cause the engaged portion 384 of the valve spool 282 to become attached to the slowly moving engaging portion 380 and be pulled upward, resulting in the engagement being positioned at the origin position. Therefore, in S17, the contact member 509 is rotated once past the origin position, and then the contact member 509 is rotated clockwise to return to the origin position. This prevents the occurrence of problems between the engaging portion 380 and the engaged portion 384, etc., as described above. In addition, the mounting head control device 400 may rotate the contact member 509 counterclockwise by the number of pulses (n3-n4) in S17 to align the contact member 509 with the origin position. In this case, S19 may not be executed.

[0073] Furthermore, after executing S19, the mounting head control device 400 determines whether the sensor 507 can detect the detection target member 505. For example, if the detection signal from the sensor 507 after executing S19 is at a high level, the mounting head control device 400 notifies the module control computer 404 that the return-to-origin operation has been completed successfully. The module control computer 404 can then begin the mounting operation. On the other hand, if the detection signal from the sensor 507 is at a low level, the mounting head control device 400 notifies the module control computer 404 of an error. This allows the module control computer 404 to take appropriate action, such as having the mounting head control device 400 perform the return-to-origin operation again or displaying an error on a display device or the like of the mounting module 10.

[0074] The relationship between the contents of the present disclosure and the terminology used in the above embodiments is as follows: The mounting head 26 is an example of a motor control device of the present disclosure. The mounting head control device 400 is an example of a control device. The first stopper 510 is an example of a stopper. S13 is an example of first rotation control, or contact control. S15 is an example of second rotation control. S17 is an example of third rotation control, or separation control. S19 is an example of fourth rotation control, or adjustment control. The first pulse count n1 is an example of a first control pulse count. The second pulse count n2 is an example of a second control pulse count. The third pulse count n3 is an example of a third control pulse count. The fourth pulse count n4 is an example of a fourth control pulse count.

[0075] The above-described embodiment provides the following effects. In one aspect of this embodiment, the mounting head control device 400 controls the driver circuit 407 with a pulse signal PS having different pulse frequencies (first pulse frequency f1 and second pulse frequency f2) for the non-contact state and the contact state. By using the first pulse frequency f1 that matches the vibration mode in the non-contact state and the second pulse frequency f2 that matches the vibration mode in the contact state, it is possible to suppress the occurrence of step-out and perform appropriate control.

[0076] The present invention is not limited to the above-described embodiment, but can be embodied in various forms with various modifications and improvements based on the knowledge of those skilled in the art. For example, in the above embodiment, the mounting head 26 is used as the motor control device of the present disclosure, but this is not limited thereto. The motor control device of the present disclosure can be any of a variety of devices that use a stepping motor and a contact member to quickly switch between target components and bring the contact member into contact with a stopper to perform a return-to-origin operation. For example, the motor control device can be a device that moves a shutter at high speed, a device that moves a component between two positions, or a device that repeatedly presses a component onto a board. Furthermore, the relationship between the first pulse frequency f1, the second pulse frequency f2, the first pulse number n1, and the second pulse number n2 can be changed as appropriate depending on the structure of the motor control device employed. Therefore, the second pulse frequency f2 may be a frequency lower than the first pulse frequency f1. The second pulse number n2 may be a pulse number greater than the first pulse number n1. Furthermore, after executing S19, the mounting head control device 400 may notify the module control computer 404 of the content of the signal without judging the detection signal of the sensor 507. Furthermore, the mounting head 26 may be configured to have only one suction nozzle 90.

[0077] The contents of the present disclosure are not limited to the dependent relationships set forth in the claims. For example, this specification also discloses the technical idea of ​​changing "the motor control device according to claim 1 or claim 2" in claim 4 to "the motor control device according to any one of claims 1 to 3." For example, this specification also discloses the technical idea of ​​changing "the motor control device according to claim 1 or claim 2" in claim 5 to "the motor control device according to any one of claims 1 to 4." For example, this specification also discloses the technical idea of ​​changing "the motor control device according to claim 1 or claim 2" in claim 6 to "the motor control device according to any one of claims 1 to 5." For example, this specification also discloses the technical idea of ​​changing "the motor control device according to claim 6" to "the motor control device according to claim 6 or claim 7" in claim 8. [Explanation of symbols]

[0078] 26 mounting head (motor control device), 90 suction nozzle, 285 switching valve, 374 switching member, 378 stepping motor, 378A output shaft, 400 mounting head control device (control device), 407 driver circuit, 505 detected member, 507 sensor, 509 contact member, 510 first stopper (stopper), f1 first pulse frequency, f2 second pulse frequency, PS pulse signal, n1 first pulse number (first control pulse number), n2 second pulse number (second control pulse number), n3 third pulse number (third control pulse number), n4 fourth pulse number (fourth control pulse number).

Claims

1. A stepping motor; a contact member that moves in response to rotation of the stepping motor; a stopper that comes into contact with the contact member and restricts movement of the contact member; a driver circuit that drives the stepping motor to rotate based on a pulse signal; a control device that outputs the pulse signal of a first pulse frequency to the driver circuit to control the driver circuit when the contact member is not in contact with the stopper, and outputs the pulse signal of a second pulse frequency, which is different from the first pulse frequency, to the driver circuit to control the driver circuit when the contact member is in contact with the stopper; A motor control device comprising:

2. The first pulse frequency is 2. The motor control device according to claim 1, wherein a frequency is set in accordance with the vibration direction of the vibration generated in the contact member in a non-contact state, and the frequency is set so that pulses switch at one of the following times: when the contact member vibrates in a direction opposite to a direction in which it is desired to move the contact member in response to rotation of the stepping motor; or when the vibration direction changes from the direction in which it is desired to move the contact member in response to rotation of the stepping motor to a direction opposite to that in which it is desired to move the contact member.

3. The second pulse frequency is 3. The motor control device according to claim 1, wherein a frequency is set in accordance with the vibration direction of the vibration generated in the contact member in a contact state, and the frequency is set so that pulses switch at one of the following times: when the contact member is vibrating in a direction in which it is desired to move the contact member in response to rotation of the stepping motor; or when the vibration direction changes from a direction opposite to the direction in which it is desired to move the contact member in response to rotation of the stepping motor toward the direction in which it is desired to move the contact member.

4. The second pulse frequency is 3. The motor control device according to claim 1, wherein the frequency is higher than the first pulse frequency.

5. The contact member is A stepper motor is attached to the output shaft of the stepper motor and rotates together with the output shaft. The stopper is The motor control device according to claim 1 or 2, wherein movement of the contact member in the rotational direction is restricted.

6. The control device a first rotation control that controls the driver circuit with the pulse signal of the first pulse frequency to move the contact member toward the stopper; a second rotation control that controls the driver circuit with the pulse signal of the second pulse frequency after the first rotation control is executed and the contact member comes into contact with the stopper, thereby moving the contact member toward the stopper; a third rotation control that switches the rotation direction of the stepping motor after executing the second rotation control, moves the contact member in a direction away from the stopper, and controls the driver circuit by a predetermined third control pulse number using the pulse signal of the first pulse frequency to move the contact member; a fourth rotation control that switches the rotation direction of the stepping motor after executing the third rotation control, moves the contact member in a direction approaching the stopper, and controls the driver circuit by a predetermined fourth control pulse number using the pulse signal of the first pulse frequency to move the contact member, thereby aligning the rotation position of the stepping motor with a predetermined rotation position; The motor control device according to claim 1 or 2, wherein the motor control device executes the above.

7. a detection target member attached to an output shaft of the stepping motor and rotating together with the output shaft; a sensor that detects the detection member when the detection member is located at a predetermined rotational position in the rotation direction; Furthermore, The control device The motor control device according to claim 6 , further comprising: a determination as to whether or not the detection target member can be detected by the sensor after the fourth rotation control is executed.

8. The control device In the first rotation control, the driver circuit is controlled by the pulse signal of the first pulse frequency for a predetermined number of first control pulses, and then the second rotation control is started; The first control pulse number is 7. The motor control device according to claim 6, wherein the first pulse frequency is the number of pulses required to move the contact member from a preset origin position to a position where the contact member contacts the stopper.

9. A stepping motor; a contact member that moves in response to rotation of the stepping motor; a stopper that comes into contact with the contact member and restricts movement of the contact member; a driver circuit that drives the stepping motor to rotate based on a pulse signal; a control device that outputs the pulse signal of a first pulse frequency to the driver circuit to control the driver circuit when the contact member is not in contact with the stopper, and outputs the pulse signal of a second pulse frequency, which is different from the first pulse frequency, to the driver circuit to control the driver circuit when the contact member is in contact with the stopper; Equipped with The control device contact control for moving the contact member toward the stopper; a separation control in which, after the contact control is executed and the contact member comes into contact with the stopper, a rotation direction of the stepping motor is switched to move the contact member in a direction away from the stopper, and the driver circuit is controlled by a predetermined number of pulses to move the contact member; an adjustment control for switching the rotation direction of the stepping motor after executing the separation control, controlling the driver circuit to move the contact member in a direction approaching the stopper, and aligning the rotation position of the stepping motor with a predetermined rotation position; A motor control device that performs the above.

10. The motor control device according to claim 1 or 2; a suction nozzle that sucks a component when a negative pressure is supplied thereto, and that releases the suction of the component and places the component on a board when the supply of negative pressure is stopped; a switching valve for switching whether or not negative pressure is supplied to the suction nozzle; a switching member that moves in response to rotation of the stepping motor of the motor control device and switches the switching valve; A mounting head comprising:

11. A stepping motor; a contact member that moves in response to rotation of the stepping motor; a stopper that comes into contact with the contact member and restricts movement of the contact member; a driver circuit that drives the stepping motor to rotate based on a pulse signal; A control method for a motor control device comprising: a first control step of outputting the pulse signal of a first pulse frequency to the driver circuit to control the driver circuit in a non-contact state in which the contact member is not in contact with the stopper; a second control step of outputting the pulse signal having a second pulse frequency, which is different from the first pulse frequency, to the driver circuit to control the driver circuit in a contact state in which the contact member is in contact with the stopper; A control method for a motor control device, comprising:

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