Work Machine

By employing a thinner movable-side ground wire and a thicker fixed-side ground wire in the work machine, the size reduction of the movable portion is achieved without compromising conductor resistance, addressing the challenge of increased bending radius due to thicker cables.

JP7649794B2Active Publication Date: 2025-03-21FUJI CORP
View PDF 3 Cites 0 Cited by

Patent Information

Application Number
JP2022554980
Authority / Receiving Office
JP · JP
Patent Type
Patents
Current Assignee / Owner
Filing Date
2020-10-05
Publication Date
2025-03-21
Estimated Expiration
2040-10-05

AI Technical Summary

Technical Problem

The use of a long ground cable between the forearm and the robot main body base results in increased conductor resistance, which necessitates a thicker cable. This thicker cable, however, increases the bending radius and hinders the reduction in size of the movable portion of the work machine.

Method used

The implementation of a work machine design that includes a thinner movable-side ground wire connected between the connector and the drive source, while maintaining a thicker fixed-side ground wire connected between the ground terminal and the connector. This configuration reduces the diameter of the ground wire in the movable portion, thereby minimizing the size of the movable portion.

Benefits of technology

This design effectively reduces the size of the movable portion of the work machine by minimizing the diameter of the ground wire, while ensuring that the conductor resistance remains within acceptable limits.

✦ Generated by Eureka AI based on patent content.

Smart Images

  • Figure 0007649794000001
    Figure 0007649794000001
  • Figure 0007649794000002
    Figure 0007649794000002
  • Figure 0007649794000003
    Figure 0007649794000003
Patent Text Reader

Abstract

A work machine comprising: a fixed unit; a ground terminal installed on the fixed unit; a movable unit that moves relative to the fixed unit; a drive source provided in the movable unit; a connector disposed on the fixed unit; a fixed-side ground wire connecting the ground terminal and the connector; and a movable-side ground wire connecting the connector and the drive source, and having a diameter smaller than that of the fixed-side ground wire.
Need to check novelty before this filing date? Find Prior Art

Description

[Technical field]

[0001] The present disclosure relates to a work machine equipped with a ground wire. [Background technology]

[0002] Conventionally, various techniques have been proposed for the above-mentioned working machine. For example, the technique described in the following Patent Document 1 is a wiring structure for a camera cable connected to an analog camera attached to the wrist tip of a horizontal articulated robot or a vertical articulated robot, the camera cable including a coaxial cable for transmitting the analog video signal and a camera power cable, the camera cable being passed through at least the inside of the forearm of the robot, and further, the forearm being grounded by a means for making the forearm the same potential as a base member of the robot, thereby shielding the camera cable by the forearm.

[0003] According to the description of Patent Document 1 below, making the forearm and base member of a robot have the same potential can be easily achieved without adopting a complicated structure, since the forearm and base member are generally made of conductive materials. Since the forearm of the robot is connected to the robot body base via a plurality of joints (connecting link structure), it is sufficient to electrically connect each link constituting the connecting link structure up to the forearm with an earth cable. Alternatively, the forearm and the robot body base may be directly connected with an earth cable, etc. [Prior art documents] [Patent documents]

[0004] [Patent Document 1] Patent Application No. 2004-98174 Summary of the Invention [Problem to be solved by the invention]

[0005] However, when the forearm and the robot body base are directly connected by an earth cable, the earth cable becomes long, and therefore it is necessary to make the earth cable thicker in order to suppress the conductor resistance value of the earth cable. Increasing the diameter of the earth cable in this way increases the bending radius of the earth cable, which may be one of the factors preventing miniaturization.

[0006] The present disclosure has been made in consideration of the above-mentioned points, and has an objective of providing a work machine that makes it possible to reduce the size of the moving part by reducing the diameter of the earth wire of the drive part provided on the moving part. [Means for solving the problem]

[0007] This specification relates to a fixed part, a ground terminal installed on the fixed part, and In at least one of the X, Y, and Z directions A work machine including a movable part that moves, a drive source provided on the movable part, a connector provided on a fixed part, a fixed-side earth wire that connects a ground terminal and the connector, and a movable-side earth wire that connects the connector and the drive source and has a smaller diameter than the fixed-side earth wire, the work machine having a plurality of movable parts and drive sources, At least one of the X, Y and Z directions The present invention discloses a work machine in which a movable side earth wire is connected to something that moves in a certain direction. Effect of the Invention

[0008] According to the present disclosure, in a work machine, by reducing the diameter of the earth wire of the drive unit provided in the movable part, it is possible to reduce the size of the movable part, for example. [Brief description of the drawings]

[0009] [Figure 1] FIG. 2 is a perspective view showing a component mounter. [Diagram 2] FIG. 2 is a perspective view showing a working head moving device of the component mounter; [Diagram 3] FIG. 2 is a block diagram showing a ground system of the component mounter. [Figure 4] FIG. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0010] Hereinafter, a component mounter according to an embodiment of the present disclosure will be described in detail with reference to the drawings. Note that in each drawing, some basic configurations are omitted, and the dimensional ratios of the depicted parts are not necessarily accurate.

[0011] 1, the component mounter 10 of this embodiment is an apparatus for performing a mounting operation of components on a circuit board 12. The component mounter 10 includes an apparatus main body 20, a board transport and holding device 22, a component mounting device 24, a mark camera 26, a parts camera 28, a component supply device 30, a bulk component supply device 32, and a control unit (see FIG. 3) 34. Examples of the circuit board 12 include a circuit board, a three-dimensional structure board, etc., and examples of the circuit board include a printed wiring board, a printed circuit board, etc.

[0012] The device body 20 is composed of a frame section 40, a beam section 42 suspended on the frame section 40, and the like. The substrate conveying and holding device 22 is disposed in the center of the frame section 40 in the front-rear direction, and has a conveying device 50 and a clamping device 52. The conveying device 50 is a device for conveying the circuit substrate 12, and the clamping device 52 is a device for holding the circuit substrate 12. As a result, the substrate conveying and holding device 22 conveys the circuit substrate 12 and holds the circuit substrate 12 fixedly at a predetermined work position. In the following description, the conveying direction of the circuit substrate 12 is referred to as the X direction, the horizontal direction perpendicular to that direction is referred to as the Y direction, and the vertical direction is referred to as the Z direction. In other words, the width direction of the component mounter 10 is the X direction, and the front-rear direction is the Y direction.

[0013] The component mounting device 24 is disposed on the beam section 42 and has two work heads 60, 62 and a work head moving device 64. A suction nozzle (not shown) is provided on the lower end surface of each of the work heads 60, 62, and the component is sucked and held by the suction nozzle. The suction nozzle is rotated by a rotation device driven by a motor (not shown), and the orientation of the sucked and held component can be adjusted. In the following, the component being sucked and held by the suction nozzle is described as the component being held by the work heads 60, 62, and the description of the suction nozzle is omitted. The work head moving device 64 has an X-direction moving device 68, a Y-direction moving device 70, and a Z-direction moving device 72. The two work heads 60, 62 can be moved integrally to any position on the frame section 40 by the X-direction moving device 68 and the Y-direction moving device 70. In addition, each of the work heads 60, 62 is detachably attached to two Z-direction sliders (not shown), and the Z-direction moving device 72 moves each of the Z-direction sliders individually in the vertical direction. In other words, the work heads 60, 62 can be moved individually in the vertical direction by the Z-direction moving device 72.

[0014] Mark camera 26 is attached to one of the two Z-direction sliders (the one to which working head 60 is attached) while facing downward, and can move in the X-, Y-, and Z-directions together with working head 60. In this way, mark camera 26 images any position on frame section 40. Part camera 28 is disposed between base material conveying and holding device 22 and component supplying device 30 on frame section 40 while facing upward, as shown in FIG. In this way, part camera 28 images the components held by working heads 60, 62.

[0015] The component supply device 30 is disposed at the front end in the front-rear direction of the frame portion 40. The component supply device 30 has a tray-type component supply device 78 and a feeder-type component supply device (not shown). The tray-type component supply device 78 is a device that supplies components placed on a tray. The feeder-type component supply device is a device that supplies components by a tape feeder or a stick feeder (not shown).

[0016] In the component mounter 10, the control unit 34 performs the operation of mounting components on the circuit board 12 held by the board conveying and holding device 22. In the component mounter 10, it is possible to mount various components on the circuit board 12, but the following describes the case where a lead component (not shown) having leads is mounted on the circuit board 12.

[0017] Specifically, the circuit board 12 is transported to a work position, where it is fixedly held by the clamp device 52. Next, the mark camera 26 moves above the circuit board 12 and captures an image of the circuit board 12. Then, the control unit 34 calculates the position coordinates in the XY directions of an insertion hole (not shown) formed in the circuit board 12 based on the captured image data.

[0018] The component supply device 30 supplies a component at a predetermined supply position. Then, one of the work heads 60 and 62 moves above the component supply position and holds the component. The work heads 60 and 62 hold the component on the upper surface of the component body.

[0019] Next, the working heads 60, 62 holding the parts move above the part camera 28, and the parts held by the working heads 60, 62 are imaged by the part camera 28. Then, the control unit 34 calculates the position coordinates in the X and Y directions of the parts held by the working heads 60, 62 based on the image data.

[0020] Next, the working heads 60, 62 holding the components move above the circuit board 12 to correct any errors in the holding position of the circuit board 12, errors in the holding position of the components, etc. Then, the working heads 60, 62 release their hold on the components, whereby the components are mounted on the circuit board 12.

[0021] Next, the work head moving device 64 will be described with reference to Fig. 2. The work head moving device 64 shown in Fig. 2 is an example of an embodiment suitable for this disclosure among those that can be mounted on the component mounter 10 of this embodiment, but is an embodiment different from that shown in Fig. 1. In the following description, parts that are substantially the same as those in Fig. 1 will be assigned the same reference numerals. Note that the work head 62 and the Z-direction moving device 72 are omitted in Fig. 2.

[0022] 2, the work head moving device 64 is provided in the device body 20, and includes an X-direction moving device 68 and a Y-direction moving device 70. The X-direction moving device 68 includes an X-direction linear motor 100 and an X-direction wiring guide device 102. The Y-direction moving device 70 includes a Y-direction linear motor 110 and a Y-direction wiring guide device 112.

[0023] The Y-direction linear motor 110 includes a pair of Y-direction stators 114A, 114B and a pair of Y-direction movers 116A, 116B. Each Y-direction stator 114A, 114B is a linear arrangement of multiple permanent magnets, and extends along the Y direction at a predetermined interval in the X direction. As a result, each Y-direction stator 114A, 114B faces each other in the X direction. Each Y-direction mover 116A, 116B is a so-called slider, has an armature core around which a coil is wound, and moves while being magnetically levitated on each Y-direction stator 114A, 114B.

[0024] The Y-direction wiring guide device 112 is a Cableveyor (registered trademark). A tip 117 of the Y-direction wiring guide device 112 is fixed to the Y-direction mover 116A. In contrast, a base end 118 of the Y-direction wiring guide device 112 is fixed to the device body 20. This allows the bent portion of the Y-direction wiring guide device 112 to move in accordance with the movement of the Y-direction mover 116A.

[0025] The X-direction linear motor 100 includes an X-direction stator 104 and an X-direction mover 106. The X-direction stator 104 is a linear arrangement of multiple permanent magnets, and extends along the X-direction. Furthermore, both ends of the X-direction stator 104 are supported by Y-direction movers 116A and 116B of the Y-direction linear motor 110. The X-direction mover 106 is a so-called slider, has an armature core around which a coil is wound, and moves while being magnetically levitated on the X-direction stator 104. Furthermore, a working head 60 is attached to the X-direction mover 106.

[0026] The X-direction wiring guide device 102 is a Cableveyor (registered trademark). A tip 107 of the X-direction wiring guide device 102 is fixed to the X-direction mover 106. In contrast, a base end 108 of the X-direction wiring guide device 102 is fixed to the X-direction stator 104. This allows the bent portion of the X-direction wiring guide device 102 to move in accordance with the movement of the X-direction mover 106.

[0027] With this configuration, the Y-direction movers 116A and 116B of the Y-direction linear motor 110, the X-direction linear motor 100, the X-direction wiring guide device 102, and the working head 60 can move together along the Y direction as shown by the arrow AY. Furthermore, the X-direction mover 106 of the X-direction linear motor 100 and the working head 60 can move together along the X direction as shown by the arrow AX.

[0028] A plurality of wires connected to the X-direction mover 106 of the X-direction linear motor 100 and a plurality of wires connected to the working head 60 are retracted into the device body 20 from a retracted position P of the device body 20. The retracted position P is located adjacent to the base end 118 of the Y-direction wiring guide device 112 in the housing 21 of the device body 20. Furthermore, each wire retracted from the retracted position P passes through the base end 118 of the Y-direction wiring guide device 112, passes through the Y-direction wiring guide device 112 and the X-direction wiring guide device 102, and is connected to the X-direction mover 106 of the X-direction linear motor 100 and the working head 60.

[0029] Similarly, the multiple wires connected to the Y-direction mover 116A of the Y-direction linear motor 110 are drawn into the device body 20 from the retracted position P of the device body 20. Furthermore, each wire drawn from the retracted position P passes through the Y-direction wire guide device 112 via the base end 118 of the Y-direction wire guide device 112, and is connected to the Y-direction mover 116A of the Y-direction linear motor 110.

[0030] Of the pair of Y-direction movers 116A, 116B of the Y-direction linear motor 110, a plurality of wires connected to the Y-direction mover 116B are drawn into the device body 20 from a retracted position (not shown) different from the retracted position P of the device body 20. Furthermore, each wire drawn in this way is connected to the Y-direction mover 116B of the Y-direction linear motor 110 through a Y-direction wire guide device (not shown) different from the Y-direction wire guide device 112. However, the plurality of wires connected to the Y-direction mover 116B of the Y-direction linear motor 110 may be drawn into the device body 20 from the retracted position P of the device body 20 in the same manner as the plurality of wires connected to the Y-direction mover 116A of the Y-direction linear motor 110. In such a case, each wire drawn in from the retracted position P is connected to the Y-direction mover 116B of the Y-direction linear motor 110 via, for example, the Y-direction wire guide device 112 and the X-direction stator 104 of the X-direction linear motor 100.

[0031] Next, the earth system of the X-direction moving device 68 will be described. As shown in Fig. 3, an earth wire 140 is connected to the X-direction moving device 68 and a ground terminal 126. The earth wire 140 extends from the X-direction mover 106 of the X-direction linear motor 100. The ground terminal 126 is provided on a housing 124 of the servo amplifier 122. The housing 124 of the servo amplifier 122 is grounded. With this configuration, the X-direction linear motor 100 is so-called housing grounded.

[0032] The servo amplifier 122 performs operation control (e.g., feedback control) of the X-direction linear motor 100, and constitutes a part of the control unit 34 that controls the component mounter 10 of this embodiment. The servo amplifier 122 is provided in a fixed state at a predetermined position within the device body 20. In this manner, the ground terminal 126 is provided within the device body 20. Note that, although other servo amplifiers (e.g., a servo amplifier that controls the operation of the Y-direction linear motor 110, etc.) are not shown, they are provided in parallel with the servo amplifier 122 from the viewpoint of convenience during maintenance, etc.

[0033] The earth wire 140 includes a movable-side earth wire 142 and a fixed-side earth wire 144. The movable-side earth wire 142 is one of a plurality of wires connected to the X-direction mover 106 of the X-direction linear motor 100 described above. Therefore, the movable-side earth wire 142 is drawn into the device body 20 from the drawing position P of the device body 20, passes through the base end 118 of the Y-direction wiring guide device 112, passes through the Y-direction wiring guide device 112 and the X-direction wiring guide device 102, and is connected to the X-direction mover 106 of the X-direction linear motor 100. With this configuration, the movable-side earth wire 142 is guided while being supported by the Y-direction wiring guide device 112 and the X-direction wiring guide device 102. Therefore, the bent portion of the movable-side earth wire 142 moves following the movements of the Y-direction movers 116A and 116B of the Y-direction linear motor 110 and the X-direction mover 106 of the X-direction linear motor 100.

[0034] On the other hand, the fixed side earth wire 144 is connected to the ground terminal 126 of the housing 124 of the servo amplifier 122 and is drawn out to the outside of the housing 21 of the device main body 20. Therefore, unlike the movable side earth wire 142, the fixed side earth wire 144 does not move.

[0035] Furthermore, the movable side earth wire 142 and the fixed side earth wire 144 are connected to a connector 132. The connector 132 is a component for connecting earth wires together, and is provided on the outer surface of the housing 21 of the device body 20 in the vicinity of the retraction position P of the device body 20, and has a first terminal 134 and a second terminal 136. In the connector 132, the movable side earth wire 142 is connected to the first terminal 134, and the fixed side earth wire 144 is connected to the second terminal 136. With this configuration, the movable side earth wire 142 and the fixed side earth wire 144 are directly connected by the connector 132.

[0036] The movable-side earth wire 142 is made thinner than the fixed-side earth wire 144, thereby making the diameter of the bent portion of the movable-side earth wire 142 smaller. However, the earth wire 140 has a set allowable conductor resistance. Therefore, the thickness of the movable-side earth wire 142 is selected so that the sum of the conductor resistance value of the movable-side earth wire 142 and the conductor resistance value of the fixed-side earth wire 144 is smaller than the allowable conductor resistance value. In this case, if the fixed-side earth wire 144 has a larger diameter, the movable-side earth wire 142 can be made even thinner.

[0037] 4, the movable-side ground wire 142 is housed in a cable 150. In addition to the movable-side ground wire 142, the cable 150 includes three signal wires 152, 154, and 156, an inclusion 158, a shield 160, and a sheath 162. The signal wires 152, 154, and 156 are wirings connected to the X-direction mover 106 of the X-direction linear motor 100. In the cable 150, the movable-side ground wire 142 and the signal wires 152, 154, and 156 are covered by the shield 160 and the sheath 162 while being surrounded by the inclusion 158. The cable 150 may also include a power line.

[0038] The cable 150 is drawn into the device body 20 from the retraction position P of the device body 20, passes through the base end 118 of the Y-direction wiring guide device 112, and is passed through the Y-direction wiring guide device 112 and the X-direction wiring guide device 102. Furthermore, near the retraction position P of the device body 20, the movable side earth wire 142 extends from the cable 150 and is connected to the first terminal 134 of the connector 132.

[0039] With this configuration, the reduction in diameter of the movable ground wire 142 makes it possible to reduce the diameter of the bent portion of the cable 150, and in turn, to reduce the diameter of the bent portions of the Y-direction wiring guide device 112 and the X-direction wiring guide device 102. This allows the work head moving device 64 to be made more compact.

[0040] As described above in detail, the component mounter 10 of this embodiment makes it possible to reduce the size of the work head moving device 64 by reducing the diameter of the movable side earth wire 142 of the X-direction linear motor 100 provided in the work head moving device 64.

[0041] The signal lines 152, 154, and 156 are connected to the servo amplifier 122 by the cable 150 being drawn into the device main body 20. The fixed-side earth wire 144 is housed in the cable 150 together with the signal lines 152, 154, and 156. In the vicinity of the housing 124 of the servo amplifier 122, the fixed-side earth wire 144 extends from the cable 150 and is connected to the ground terminal 126. In contrast, in the vicinity of the lead-in position P of the device main body 20, the fixed-side earth wire 144 extends from the cable 150 and is connected to the second terminal 136 of the connector 132.

[0042] Incidentally, in this embodiment, the component mounter 10 is an example of a work machine. The device body 20 is an example of a fixed part. The work head moving device 64 (excluding the pair of Y-direction stators 114A, 114B) is an example of a movable part. The X-direction linear motor 100 is an example of a drive source. The X-direction wiring guide device 102 is an example of a driven member. The Y-direction linear motor 110 is an example of a drive source. The Y-direction wiring guide device 112 is an example of a driven member. The pair of Y-direction stators 114A, 114B are an example of a pair of stators. The pair of Y-direction movers 116A, 116B are an example of a pair of movers. The base end 118 is an example of a fixed end of a follower member. The servo amplifier 122 is an example of a control device. The housing 124 of the servo amplifier 122 is an example of a housing. Each signal line 152, 154, 156 of the X-direction linear motor 100 is an example of a signal line of a drive source.

[0043] The present disclosure is not limited to the above-described embodiment, and various modifications are possible without departing from the spirit of the present disclosure. For example, the ground terminal 126 is not limited to being provided inside the device main body 20, but may be provided in the device main body 20. In addition, the ground terminal 126 may be grounded without passing through the housing 124 of the servo amplifier 122.

[0044] Also, instead of the X-direction wiring guide device 102 and the Y-direction wiring guide device 112, a flexible flat cable including the movable side ground wire 142 may be used. In such a case, the cable 150 is not necessary. Incidentally, the flexible flat cable is an example of a driven member.

[0045] In addition, in this embodiment, the movable side ground wire 142 is described as being connected to the X-direction mover 106 of the X-direction linear motor 100, but it may be connected to the Y-direction mover 116A of the Y-direction linear motor 110, the Z-direction moving device 72, or each of the work heads 60, 62, etc. However, in the case of the Y-direction mover 116A of the Y-direction linear motor 110, the movable side ground wire 142 is drawn into the device body 20 from the drawing position P of the device body 20, passes through the base end 118 of the Y-direction wiring guide device 112, passes through the Y-direction wiring guide device 112, and is connected to the Y-direction mover 116A of the Y-direction linear motor 110.

[0046] Furthermore, in the X-direction linear motor 100, an armature core with a coil wound thereon may be provided in the X-direction stator 104, and multiple permanent magnets may be provided in the X-direction mover 106, as opposed to the above embodiment. In such a case, the mover-side earth wire 142 is drawn into the device body 20 from the retraction position P of the device body 20, passes through the base end 118 of the Y-direction wiring guide device 112, passes through the Y-direction wiring guide device 112, and is connected to the X-direction stator 104 of the X-direction linear motor 100.

[0047] Furthermore, in this embodiment, the work machine has been described as the component mounter 10, but it may also be an appearance inspection device, a printing device, a machine tool, or the like. [Explanation of symbols]

[0048] 10: component mounting machine, 20: device body, 64: work head moving device, 100: X-direction linear motor, 102: X-direction wiring guide device, 110: Y-direction linear motor, 112: Y-direction wiring guide device, 114A, 114B: pair of Y-direction stators, 116A, 116B: pair of Y-direction movers, 118: base end of Y-direction wiring guide device, 122: servo amplifier, 124: servo amplifier housing, 126: ground terminal, 132: connector, 142: movable side earth wire, 144: fixed side earth wire, 150: cable, 152: signal line of X-direction linear motor, 154: signal line of X-direction linear motor, 156: signal line of X-direction linear motor, P: retraction position

Claims

1. A fixed portion; A ground terminal installed on the fixed portion; a movable part that moves in at least one direction among an X direction, a Y direction, and a Z direction relative to the fixed part; A drive source provided to the movable part; A connector disposed on the fixed portion; a fixed-side earth wire connecting the ground terminal and the connector; A work machine including a movable-side earth wire that connects the connector and the drive source and has a smaller diameter than the fixed-side earth wire, A work machine having a plurality of the movable parts and the drive sources, and the movable side earth wire is connected to one of the plurality of movable parts that moves in at least one of the X direction, Y direction, and Z direction.

2. 2. The work machine according to claim 1, wherein the thickness of the movable side earth wire is set so that the sum of the conductor resistance value of the movable side earth wire and the conductor resistance value of the fixed side earth wire is smaller than the allowable value of the conductor resistance.

3. 3. The work machine according to claim 1, wherein the connector is disposed in the vicinity of a retraction position where the movable side earth wire is retracted into the movable part.

4. the movable portion includes a driven member that supports and guides the movable-side earth wire by moving a bent portion of the movable-side earth wire following the movement of the driving source, 4. The work machine according to claim 3, wherein the retracted position of the movable side earth wire is adjacent to a fixed end of the driven member.

5. The work machine according to any one of claims 1 to 4, further comprising a cable including a signal line of the drive source and a ground line of the movable side.

6. A control device fixed at a predetermined position within the fixed portion; a housing in which the control device is disposed, The work machine according to claim 1 , wherein the ground terminal is provided on the housing.

7. The drive source includes a pair of movers, 7. The work machine according to claim 1, wherein the pair of movers move on a pair of stators provided on the fixed portion while facing each other with a predetermined gap therebetween.

Citation Information

Patent Citations

  • Information processor

    JP1989088632A

  • Articulated clean robot

    JP1999138488A

  • Wiring structure of cable for camera and cable for force sensor in robot system

    JP2004098174A