JP7649794B2 - Work Machine - Google Patents

Description

This disclosure relates to a work machine equipped with an earth wire.

Various technologies have been proposed in the past for the above-mentioned working machine. For example, the technology 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 the base member of the robot, thereby shielding the camera cable by the forearm.

According to the description in Patent Document 1 below, making the forearm and base member of a robot have the same potential can be easily achieved without adopting a complex 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 multiple joints (connecting link structure), each link that makes up the connecting link structure leading to the forearm can be electrically connected with an earth cable. Alternatively, the forearm and the robot body base can be directly connected with an earth cable, etc.

Patent Application No. 2004-98174

However, when connecting the forearm and the robot body base directly with an earth cable, the earth cable becomes long, and in order to suppress the conductor resistance value of the earth cable, it is necessary to make the earth cable thicker. 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 that hinder miniaturization.

The present disclosure has been made in consideration of the above-mentioned points, and aims to provide a work machine that can reduce the size of the moving part by reducing the diameter of the earth wire of the drive unit provided in the moving part.

This specification discloses a work machine including a fixed part, a ground terminal installed on the fixed part, a movable part that moves in at least one of the X-, Y-, and Z-directions relative to the fixed part, a drive source provided on the movable part, a connector disposed on the fixed part, a fixed-side earth wire connecting the 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, wherein the work machine has a plurality of movable parts and 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-, Y-, and Z-directions .

According to the present disclosure, the working machine can, for example, reduce the size of the moving part by reducing the diameter of the earth wire of the drive unit provided in the moving part.

FIG. 2 is a perspective view showing a component mounter. FIG. 2 is a perspective view showing a working head moving device of the component mounter; FIG. 2 is a block diagram showing a ground system of the component mounter. FIG.

Below, 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 of the basic configuration is omitted, and the dimensional ratios of the various parts depicted are not necessarily accurate.

As shown in FIG. 1, the component mounter 10 of this embodiment is a device for performing component mounting work on a circuit board 12. The component mounter 10 includes a device main body 20, a substrate 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 substrate 12 include a circuit board and a substrate with a three-dimensional structure, and examples of the circuit substrate include a printed wiring board and a printed circuit board.

The device body 20 is composed of a frame section 40 and a beam section 42 suspended on the frame section 40. The substrate transport and holding device 22 is disposed in the center of the frame section 40 in the front-rear direction, and has a transport device 50 and a clamp device 52. The transport device 50 is a device that transports the circuit substrate 12, and the clamp device 52 is a device that holds the circuit substrate 12. As a result, the substrate transport and holding device 22 transports the circuit substrate 12 and holds the circuit substrate 12 fixedly at a predetermined work position. In the following description, the transport 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.

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. The lower end surface of each work head 60, 62 is provided with a suction nozzle (not shown), which is used to suction and hold the component. The suction nozzle is rotated by a rotating device driven by a motor (not shown), and the orientation of the component that is suctioned and held can be adjusted. In the following, the fact that the component is suctioned 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 also 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 removably attached to two Z-direction sliders (not shown), and the Z-direction movement 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 movement device 72.

The mark camera 26 is attached to one of the two Z-direction sliders (the one to which the work head 60 is attached) while facing downward, and can move in the X-, Y-, and Z-directions together with the work head 60. This allows the mark camera 26 to capture an image of any position on the frame section 40. As shown in FIG. 1, the part camera 28 is disposed between the base material conveying and holding device 22 and the part supplying device 30 on the frame section 40 while facing upward. This allows the part camera 28 to capture an image of the parts held by the work heads 60, 62.

The component supply device 30 is disposed at the front end of the frame portion 40 in the front-rear direction. 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 using a tape feeder or stick feeder (not shown).

In the component mounter 10, the control unit 34 mounts components onto the circuit board 12 held by the substrate transport and holding device 22. The component mounter 10 is capable of mounting various components onto the circuit board 12, but the following describes the case where a lead component (not shown) having leads is mounted onto the circuit board 12.

Specifically, the circuit board 12 is transported to the work position and fixedly held at that position 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. The control unit 34 then calculates the position coordinates in the XY directions of the insertion hole (not shown) formed in the circuit board 12 based on the captured image data.

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

Next, the work heads 60, 62 holding the parts move above the parts camera 28, and the parts held by the work heads 60, 62 are imaged by the parts camera 28. The control unit 34 then calculates the position coordinates in the XY directions of the parts held by the work heads 60, 62 based on the image data.

Then, the work 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 and the components. The work heads 60, 62 then release their hold on the components, and the components are attached to the circuit board 12.

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 of 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, etc., are omitted in FIG. 2.

As shown in FIG. 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.

The Y-direction linear motor 110 is equipped with 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, which extend 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, which has an armature core wound with a coil, and moves while being magnetically levitated on each Y-direction stator 114A, 114B.

The Y-direction wiring guide device 112 is a Cableveyor (registered trademark). The tip 117 of the Y-direction wiring guide device 112 is fixed to the Y-direction mover 116A. In contrast, the 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.

The X-direction linear motor 100 is equipped with 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 the 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 wound with a coil, and moves while being magnetically levitated on the X-direction stator 104. Furthermore, a work head 60 is attached to the X-direction mover 106.

The X-direction wiring guide device 102 is a Cableveyor (registered trademark). The tip 107 of the X-direction wiring guide device 102 is fixed to the X-direction mover 106. In contrast, the 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.

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 work 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 work head 60 can move together along the X direction as shown by the arrow AX.

The multiple wires connected to the X-direction mover 106 of the X-direction linear motor 100 and the multiple wires connected to the work head 60 are retracted into the device body 20 from the retraction position P of the device body 20. The retraction 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 retraction 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 work head 60.

The multiple wirings connected to the Y-direction mover 116A of the Y-direction linear motor 110 are similarly retracted into the device body 20 from the retraction position P of the device body 20. Furthermore, each wiring retracted from the retraction 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 is connected to the Y-direction mover 116A of the Y-direction linear motor 110.

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

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 the 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.

The servo amplifier 122 controls the operation of the X-direction linear motor 100 (e.g., feedback control), and constitutes part of the control unit 34 that controls the component mounter 10 of this embodiment. The servo amplifier 122 is provided in a fixed position within the device body 20. In this way, 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 together with the servo amplifier 122 from the viewpoint of convenience during maintenance, etc.

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 the multiple 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 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 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 part of the movable side earth wire 142 moves following the movement of each Y-direction mover 116A, 116B of the Y-direction linear motor 110 and the X-direction mover 106 of the X-direction linear motor 100.

In contrast, the fixed side earth wire 144 is connected to the ground terminal 126 of the housing 124 of the servo amplifier 122 and is pulled 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.

Furthermore, the movable side earth wire 142 and the fixed side earth wire 144 are connected to the 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 near 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.

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 is made thicker, the movable side earth wire 142 can be made even thinner.

The movable side earth wire 142 is housed in a cable 150 as shown in FIG. 4. In addition to the movable side earth wire 142, the cable 150 includes three signal wires 152, 154, 156, an inclusion 158, a shield 160, and a sheath 162. Each of the signal wires 152, 154, 156 is a wiring connected to the X-direction mover 106 of the X-direction linear motor 100. In the cable 150, the movable side earth wire 142 and each of the signal wires 152, 154, 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.

The cable 150 is pulled 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.

With this configuration, the diameter of the movable ground wire 142 can be reduced, which in turn makes it possible to reduce the diameter of the bent portion of the cable 150, and thus the diameter of the bent portion 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 smaller.

As described in detail above, the component mounter 10 of this embodiment can 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.

The signal lines 152, 154, and 156 are connected to the servo amplifier 122 by the cable 150 being pulled into the device main body 20. The fixed side earth wire 144 is also 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 pull-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.

Incidentally, in this embodiment, the component mounting machine 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 dependent 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 of the signal lines 152, 154, and 156 of the X-direction linear motor 100 is an example of a signal line of a drive source.

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 any terminal 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.

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

In addition, in this embodiment, the movable side earth 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 work head 60, 62, etc. However, in the case of the Y-direction mover 116A of the Y-direction linear motor 110, the movable 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 Y-direction mover 116A of the Y-direction linear motor 110.

In addition, in the X-direction linear motor 100, as opposed to the above embodiment, an armature core with a coil wound thereon may be provided on the X-direction stator 104, and multiple permanent magnets may be provided on the X-direction mover 106. 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.

In addition, in this embodiment, the work machine is described as a component mounter 10, but it may also be an appearance inspection device, a printing device, a machine tool, or the like.

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 (7)

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 . The work machine according to claim 1, wherein the thickness of the movable earth wire is set so that the sum of the conductor resistance value of the movable earth wire and the conductor resistance value of the fixed earth wire is smaller than the allowable value of the conductor resistance. The work machine according to claim 1 or 2, wherein the connector is disposed near a retraction position where the movable side earth wire is retracted into the movable part. 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,
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. The work machine according to any one of claims 1 to 4, comprising a cable including a signal line of the drive source and a ground wire on the movable side. 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. 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.

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