Brake system

Abstract

To enable stable braking of a robot arm and a mobile device at the time of emergency stop.SOLUTION: A brake system 100 includes: a robot arm 20 having a link 31 and a first motor 33 that drives the link 31; a conveyance device 3 having a shuttle bar 113 and a second motor 121 that drives the shuttle bar 113; and control devices 4, 5 for controlling the first motor 33 and the second motor 121. The control devices 4, 5 cause a dynamic brake to act in cooperation with the first motor 33 and the second motor 121 at the time of emergency stop.SELECTED DRAWING: Figure 1

Description

[Technical field]

[0001] The technology disclosed herein relates to braking systems. [Background technology]

[0002] Conventionally, braking systems that brake a motor in a robot arm driven by the motor have been known. For example, the braking system disclosed in Patent Document 1 applies dynamic braking to the motor under predetermined conditions. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] JP 2020-162193 A Summary of the Invention [Problem to be solved by the invention]

[0004] Incidentally, the robot arm may be used together with a moving device such as a transport device for transporting a workpiece. In this case, it is desirable to stably brake the robot arm and the moving device so that they do not interfere with each other in the event of an emergency stop.

[0005] The technology disclosed herein has been made in consideration of the above points, and its purpose is to stably brake the robot arm and the moving device during an emergency stop. [Means for solving the problem]

[0006] The braking system disclosed herein includes a robot arm having a link and a robot motor that drives the link, a moving device having a moving body and a moving body motor that drives the moving body, and a control device that controls the robot motor and the moving body motor, and in the event of an emergency stop, the control device applies dynamic brakes to the robot motor and the moving body motor in coordination. Effect of the Invention

[0007] According to the braking system, the robot arm and the moving device can be stably braked in the event of an emergency stop. [Brief description of the drawings]

[0008] [Figure 1] FIG. 1 is a schematic diagram showing a braking system according to an embodiment. [Diagram 2] FIG. 2 is a schematic diagram showing a robot. [Diagram 3] FIG. 3 is a schematic perspective view showing the conveying device. [Figure 4] FIG. 4 is a block diagram showing the configuration of the first control device. [Diagram 5] FIG. 5 is a circuit diagram showing a converter circuit, a regenerative circuit, and an inverter circuit of the first control device. [Figure 6] FIG. 6 is a block diagram showing the functions of the processor of the first control device. [Figure 7] FIG. 7 is a block diagram showing the configuration of the second control device. [Figure 8] FIG. 8 is a circuit diagram showing a converter circuit, a regenerative circuit, and an inverter circuit of the second control device. [Figure 9] FIG. 9 is a block diagram showing the functions of the processor of the second control device. [Figure 10] FIG. 10 is a schematic time chart showing the control of the transport device by the second control device during normal operation. [Figure 11] FIG. 11 is a schematic time chart showing the control of the transport device by the second control device at the time of an emergency stop. [Figure 12] FIG. 12 is a block diagram showing a configuration of a control device for a braking system according to the first modification. [Figure 13] FIG. 13 is a circuit diagram showing a converter circuit, a regenerative circuit, a first inverter circuit, and a second inverter circuit of the control device. [Figure 14]FIG. 14 is a block diagram showing the functions of the processor of the control device. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0009] An exemplary embodiment will be described in detail below with reference to the drawings. FIG. 1 is a schematic diagram showing a braking system 100 according to an embodiment. The braking system 100 includes a robot arm 20 of a robot 2, a transport device 3, a first control device 4, and a second control device 5. The braking system 100 brakes the robot arm 20 of the robot 2 and the transport device 3. The transport device 3 is an example of a "moving device". The first control device 4 is an example of a "robot control device". The second control device 5 is an example of a "moving body control device".

[0010] The transport device 3 transports the workpiece W. More specifically, the transport device 3 is loaded with the workpiece W in a first area Z1 on the left side of Fig. 1, and transports the workpiece W from the first area Z1 to a second area Z2 on the right side of Fig. 1. In this example, the workpiece W is a vehicle body.

[0011] In this example, the robot 2 is an industrial robot. More specifically, the robot 2 is a welding robot that welds the workpiece W. The robot 2 is placed in the second area Z2, and welds the workpiece W transported to the second area Z2. That is, the robot 2 and the transport device 3 work together.

[0012] The first control device 4 controls the operation of the robot arm 20. The second control device 5 controls the operation of the transport device 3. The first control device 4 and the second control device 5 cooperatively control the robot arm 20 and the transport device 3. Cooperative control means synchronizing the control of the robot arm 20 by the first control device 4 and the control of the transport device 3 by the second control device 5. This allows the operation of the robot arm 20 and the operation of the transport device 3 to be synchronized.

[0013] (Robot 2 Configuration) 2 is a schematic diagram showing the robot 2. The robot 2 includes a base 11 and a robot arm 20 supported by the base 11. The base 11 is fixed to an installation target such as a floor. The base 11 is made of, for example, metal. The base 11 is, for example, substantially box-shaped.

[0014] The robot arm 20 is connected to the base 11. The robot arm 20 in this example is a vertical articulated type. The robot arm 20 has an arm body 30 connected to the base 11 and an end effector 35 connected to the arm body 30.

[0015] The arm body 30 has a plurality of links 31 and joints 32 that rotatably connect the links 31 to one another. In this example, the arm body 30 has five links 31a to 31e and six joints 32a to 32f. When the five links 31a to 31e are not distinguished from one another, they are simply referred to as "links 31." When the six joints 32a to 32f are not distinguished from one another, they are simply referred to as "joints 32."

[0016] The multiple links 31 are connected in series. Specifically, the five links 31a to 31e are connected in order from the end of the arm body 30 on the base 11 side to the end of the arm body 30 opposite the base 11. Each link 31 is made of, for example, metal. Specifically, each link 31 is an aluminum casting.

[0017] A joint 32 is provided for every two adjacent links 31. Specifically, the six joints 32a to 32f are provided in order from the end of the arm body 30 on the base 11 side to the end of the arm body 30 opposite the base 11. The joint 32a connects the base 11 and the link 31a. The joint 32b connects the link 31a and the link 31b. The joint 32c connects the link 31b and the link 31c. The joint 32d connects the link 31c and the link 31d. The joint 32e connects the link 31d and the link 31e. The joint 32f connects the link 31e and the end effector 35.

[0018] Each of the joints 32 includes a first motor 33. The first motor 33 is an example of a "robot motor." Specifically, the arm body 30 has six first motors 33a to 33f. The six joints 32a to 32f include the first motors 33a to 33f. The first motors 33a to 33f are designated by the same alphabet as the corresponding joints 32a to 32f. When the six first motors 33a to 33f are not to be distinguished from each other, they are simply referred to as "first motors 33." In FIG. 2, the first motor 33 is shown at a position away from the casing of the joint 32 for convenience, but the first motor 33 is provided inside the casing or attached to the casing.

[0019] The first motor 33 is, for example, a servo motor. An encoder 36 (see FIG. 4) that detects the rotational position of the first motor 33 is attached to each first motor 33. An electromagnetic brake 37 (see FIG. 4) that brakes the first motor 33 is attached to each first motor 33. In this example, the electromagnetic brake 37 is a non-excitation operating type electromagnetic brake. The electromagnetic brake 37 has a coil and is configured to brake the first motor 33 (i.e., apply the brake) when the coil is in a non-excitation state, and not brake the first motor 33 (i.e., do not apply the brake) when the coil is in an excited state.

[0020] The first motor 33 rotates the link 31 or the end effector 35. Specifically, the first motor 33a rotates the link 31a around an axis extending vertically relative to the base 11. The first motor 33b rotates the link 31b around an axis extending horizontally relative to the link 31a. The first motor 33c rotates the link 31c around an axis extending horizontally relative to the link 31b. The first motor 33d rotates the link 31d around an axis extending in the extension direction of the link 31c relative to the link 31c. The first motor 33e rotates the link 31e around an axis extending in a direction perpendicular to the extension direction of the link 31d relative to the link 31d. The first motor 33f rotates the end effector 35 around an axis extending in the extension direction of the link 31e relative to the link 31e.

[0021] The end effector 35 is a welding gun that welds the workpiece W. More specifically, the end effector 35 is a welding device that performs arc welding.

[0022] The first control device 4 controls the robot arm 20. Specifically, the first control device 4 controls the arm body 30 and the end effector 35. The first control device 4 operates the arm body 30 by controlling each of the first motors 33. The first control device 4 executes welding of the workpiece W by the end effector 35.

[0023] (Configuration of conveying device 3) 3 is a schematic perspective view showing the transport device 3. The transport device 3 includes a base 111, a plurality of guides 112 provided on the base 111, two shuttle bars 113 movably supported by the plurality of guides 112, a plurality of stands 114 provided on the two shuttle bars 113, a plurality of stoppers 115 provided on the base 111, and a drive unit 120 that drives the two shuttle bars 113. The shuttle bar 113 is an example of a "moving body".

[0024] The base 111 is fixed to an installation target such as a floor. The base 111 is made of, for example, metal. The base 111 has a long rectangular shape in a plan view. The longitudinal direction of the base 111 coincides with the transport direction of the workpiece W. The direction perpendicular to the longitudinal direction of the base 111 is defined as the width direction of the base 111.

[0025] The multiple guides 112 are arranged along the longitudinal direction of the base 111 at both ends in the width direction of the base 111. Specifically, the conveying device 3 has 20 guides 112. Ten guides 112 are provided at one end in the width direction of the base 111, and the remaining ten guides 112 are provided at the other end in the width direction of the base 111. The guides 112 have a main body portion including a groove that opens upward, and multiple rollers provided in the groove of the main body portion. The main body portion of the guide 112 is made of, for example, metal. The rollers of the guide 112 are made of, for example, resin.

[0026] The two shuttle bars 113 include shuttle bar 113a arranged at one end of the base 111 in the width direction, and shuttle bar 113b arranged at the other end of the base 111 in the width direction. One shuttle bar 113a is supported by multiple guides 112 provided at one end of the base 111 in the width direction. The other shuttle bar 113b is supported by multiple guides 112 provided at the other end of the base 111 in the width direction. When there is no need to distinguish between the two shuttle bars 113a, 113b, they will be simply referred to as "shuttle bars 113."

[0027] The shuttle bar 113 is inserted into a groove of the guide 112 and guided by the rollers of the guide 112. In other words, the shuttle bar 113 is supported by the guide 112 so as to be movable along the longitudinal direction of the base 111. The shuttle bar 113 has a rack gear 116 on its lower part. The rack gear 116 has a gear surface on its lower surface. A driving force is transmitted to the rack gear 116 from the driving unit 120. The shuttle bar 113 is made of, for example, metal.

[0028] The multiple stands 114 are provided on the two shuttle bars 113. Specifically, the transport device 3 has four stands 114. Two stands 114 are provided on the upper surface of one shuttle bar 113a, and the remaining two stands 114 are provided on the upper surface of the other shuttle bar 113b. The stands 114 support the workpiece W. The stands 114 are made of, for example, metal.

[0029] The multiple stoppers 115 are arranged at both ends of the base 111 in the width direction and at both ends of the base 111 in the longitudinal direction. Specifically, the conveying device 3 has four stoppers 115. Each stopper 115 is provided at both ends of the base 111 in the width direction and at both ends of the base 111 in the longitudinal direction. The stoppers 115 abut against a part of the shuttle bar 113 to prevent the shuttle bar 113 from moving outward in the longitudinal direction from both ends of the base 111 in the longitudinal direction. The stoppers 115 are made of, for example, metal.

[0030] The drive unit 120 has a plurality of second motors 121, a shaft 122 connected to the output shaft of each second motor 121 and transmitting the driving force of each second motor 121, and a pinion gear 123 attached to the tip of each shaft 122 and receiving the driving force of each second motor 121. The second motor 121 is an example of a "moving body motor".

[0031] Specifically, the drive unit 120 has two second motors 121a and 121b. One second motor 121a drives one shuttle bar 113a. The other second motor 121a drives one shuttle bar 113a. When there is no need to distinguish between the two second motors 121a and 121b, they are simply referred to as "second motors 121."

[0032] One of the second motors 121a rotates a pinion gear 123 via a shaft 122. The pinion gear 123 meshes with a rack gear 116 of one of the shuttle bars 113a and transmits the rotational force of the pinion gear 123 to the rack gear 116. This causes the shuttle bar 113a to move along the longitudinal direction of the base 111.

[0033] The other second motor 121b rotates and drives a pinion gear 123 via a shaft 122. The pinion gear 123 meshes with a rack gear 116 of the other shuttle bar 113b and transmits the rotational force of the pinion gear 123 to the rack gear 116. This causes the shuttle bar 113b to move along the longitudinal direction of the base 111.

[0034] The second motor 121 is, for example, a servo motor. An encoder 136 (see FIG. 7) that detects the rotational position of the second motor 121 is attached to each second motor 121. An electromagnetic brake 137 (see FIG. 7) that brakes the second motor 121 is attached to each second motor 121. In this example, the electromagnetic brake 137 is a non-excitation operating type electromagnetic brake. The electromagnetic brake 137 has a coil and is configured to brake the second motor 121 (i.e., apply the brake) when the coil is in a non-excitation state, and not brake the second motor 121 (i.e., do not apply the brake) when the coil is in an excited state.

[0035] The second control device 5 controls the transport device 3. Specifically, the second control device 5 controls the drive unit 120. In more detail, the second control device 5 controls the second motor 121 to operate the shuttle bar 113.

[0036] (Configuration of first control device 4) 4 is a block diagram showing the configuration of the first control device 4. The first control device 4 has a processor 41 that performs overall control of the robot arm 20, a storage device 42 that stores various programs and various data, and a memory 43. The first control device 4 further has a converter circuit 51, an emergency stop button 52, a communication module 53, a regeneration circuit 55, and a plurality of inverter circuits 56.

[0037] The storage unit 42 stores various programs and various data executed by the processor 41. The storage unit 42 is formed of a non-volatile memory, a hard disk drive (HDD), a solid state drive (SSD), etc. The memory 43 temporarily stores data, etc. For example, the memory 43 is formed of a volatile memory.

[0038] The processor 41 performs various types of arithmetic processing. Specifically, the processor 41 realizes various functions by reading a program from the storage device 42 into the memory 43 and expanding the program. For example, the processor 41 is formed of a processor such as a CPU (Central Processing Unit). The processor 41 may also be formed of an MCU (Micro Controller Unit), an MPU (Micro Processor Unit), an FPGA (Field Programmable Gate Array), a PLC (Programmable Logic Controller), a system LSI, or the like.

[0039] The processor 41 is connected to a converter circuit 51, an emergency stop button 52, and a communication module 53. The end effector 35 is also connected to the processor 41. Although not shown for convenience, the processor 41 is also connected to a regeneration circuit 55 and an inverter circuit 56.

[0040] A regenerative circuit 55 and a plurality of inverter circuits 56 are connected to the converter circuit 51. Each inverter circuit 56 is connected to a first motor 33. Specifically, one regenerative circuit 55 and six inverter circuits 56 are connected to the converter circuit 51. The converter circuit 51 converts AC power supplied from a power source into DC power. The regenerative circuit 55 consumes regenerative energy generated in the first motor 33. The inverter circuit 56 converts DC power into AC power and outputs the AC power to the first motor 33. An encoder 36 and an electromagnetic brake 37 are attached to the first motor 33a. Although not shown, the other first motors 33b to 33f are also attached with an encoder 36 and an electromagnetic brake 37.

[0041] The emergency stop button 52 outputs an emergency stop signal when pressed by a user in the event of an emergency stop. The communication module 53 has a hub, a communication cable, etc., and connects the first control device 4 to the second control device 5 so that they can communicate with each other.

[0042] FIG. 5 is a circuit diagram showing the converter circuit 51, the regenerative circuit 55, and the inverter circuit 56 of the first control device 4.

[0043] All the inverter circuits 56 are connected in parallel to the converter circuit 51. A capacitor 54 is connected between the converter circuit 51 and the inverter circuit 56. The capacitor 54 is connected in parallel to the converter circuit 51 and the inverter circuit 56. The regeneration circuit 55 is connected in parallel to the converter circuit 51 and the inverter circuit 56 between the converter circuit 51 and the inverter circuit 56, more specifically, between the capacitor 54 and the inverter circuit 56.

[0044] In this example, the converter circuit 51 converts AC power supplied from a three-phase AC power supply into DC power. The inverter circuit 56 is configured as a three-phase inverter. The first motor 33 is configured as a three-phase AC motor.

[0045] The converter circuit 51 includes, for example, a bridge diode. The converter circuit 51 is controlled by the processor 41. Specifically, the on / off of the converter circuit 51 is controlled by the processor 41. As a result, the supply or cut-off of power from the converter circuit 51 to the inverter circuit 56 is switched.

[0046] The inverter circuit 56 has six transistors 57a to 57f as arms. In this example, the transistors 57a to 57f are IGBTs (Insulated Gate Bipolar Transistors). Here, each switching element (i.e., the six transistors 57a to 57f) of the inverter circuit 56 is called an arm, and a pair of upper and lower arms in FIG. 5 is called a phase. In this example, the transistors 57a and 57d belong to the U phase, the transistors 57b and 57e belong to the V phase, and the transistors 57c and 57f belong to the W phase. The inverter circuit 56 is configured as a three-phase inverter, and thus has six arms and three phases.

[0047] The inverter circuit 56 further includes free wheel diodes 58a to 58f connected in parallel to the six transistors 57a to 57f, respectively. The free wheel diodes 58a to 58f are each arranged such that the cathode has a higher potential than the anode.

[0048] Each switching element of the inverter circuit 56 is controlled by the processor 41. Specifically, the on / off of each switching element of the inverter circuit 56 is controlled by the processor 41. As a result, the desired three-phase (U-phase, V-phase, and W-phase) power is supplied to the first motor 33. That is, the rotation speed of the first motor 33 is controlled by the inverter circuit 56.

[0049] For example, when the first motor 33 is decelerated under the control of the inverter circuit 56, the capacitor 54 can store the voltage that rises in the inverter circuit 56 as energy.

[0050] The regenerative circuit 55 has a first regenerative resistor 61, a switch 62, and a switch controller 63. The first regenerative resistor 61 is connected in parallel to the converter circuit 51 and the inverter circuit 56 between the converter circuit 51 and the inverter circuit 56, more specifically, between the capacitor 54 and the inverter circuit 56. The switch 62 is connected in series to the first regenerative resistor 61.

[0051] The first regenerative resistor 61 consumes regenerative energy generated in the first motor 33 due to the rotation of the first motor 33. The first regenerative resistor 61 is an example of a "robot regenerative resistor."

[0052] The switch 62 is configured to be switchable between a connection state in which the first regenerative resistor 61 is connected to the first motor 33 and a non-connection state in which the first regenerative resistor 61 is disconnected from the first motor 33. In this example, the switch 62 is an IGBT (Insulated Gate Bipolar Transistor).

[0053] The switch controller 63 switches the switch 62 to a connected state during an emergency stop. The switch controller 63 is controlled by the processor 41. When the switch 62 is in a connected state, the first regenerative resistor 61 is connected to the first motor 33, and the first regenerative resistor 61 consumes the regenerative energy of the first motor 33. In this manner, the regenerative circuit 55 is used to apply dynamic braking to the first motor 33 during an emergency stop. Furthermore, when the switch 62 is in a connected state, the first regenerative resistor 61 is also connected to the capacitor 54, and the first regenerative resistor 61 also consumes the energy stored in the capacitor 54.

[0054] The switch controller 63 may keep the switch 62 in the connected state even during normal operation of the robot arm 20, particularly when the first motor 33 is decelerating. This allows the first regenerative resistor 61 to consume energy associated with the voltage rising in the inverter circuit 56, for example, when the first motor 33 is decelerated under control by the inverter circuit 56.

[0055] 6 is a block diagram showing functions of the processor 41 of the first control device 4. The processor 41 has a converter circuit controller 71, an inverter circuit controller 72, a regenerative circuit controller 73, an electromagnetic brake controller 74, an end effector controller 75, and a cooperative controller 76 as functional blocks.

[0056] The converter circuit controller 71 controls the converter circuit 51. For example, the converter circuit controller 71 controls the converter circuit 51 so as to stabilize the voltage output from the converter circuit 51. Furthermore, the converter circuit controller 71 controls the converter circuit 51 so as to cut off the power from the converter circuit 51 to the inverter circuit 56 in the event of an emergency stop. That is, when the user presses down the emergency stop button 52, the converter circuit controller 71 receives an emergency stop signal from the emergency stop button 52 and cuts off the power from the converter circuit 51. As a result, the converter circuit controller 71 cuts off the power supplied to the first motor 33 in the event of an emergency stop.

[0057] The inverter circuit controller 72 controls the inverter circuit 56. Specifically, the inverter circuit controller 72 controls the on / off of each switching element of the inverter circuit 56 based on the program in the memory 42. The inverter circuit controller 72 controls the rotation speed of the first motor 33 based on the rotation position of the first motor 33 detected by the encoder 36.

[0058] The inverter circuit controller 72 may execute control for decelerating and stopping the first motor 33 in the event of an emergency stop. Specifically, when the user presses down the emergency stop button 52, the inverter circuit controller 72 may execute control for decelerating and stopping the first motor 33 upon receiving an emergency stop signal from the emergency stop button 52.

[0059] The regenerative circuit controller 73 controls the regenerative circuit 55. Specifically, the regenerative circuit controller 73 controls the switch controller 63 to connect the switch 62 in an emergency stop state. In other words, when the user presses down the emergency stop button 52, the regenerative circuit controller 73 receives an emergency stop signal from the emergency stop button 52 and controls the switch controller 63 to connect the switch 62. As a result, the regenerative circuit controller 73 applies dynamic braking to the first motor 33 in an emergency stop state.

[0060] The regenerative circuit controller 73 may control the switch controller 63 to keep the switch 62 in the connected state even during normal operation, particularly when the first motor 33 is decelerating. This allows the first regenerative resistor 61 to consume energy associated with the voltage that rises in the inverter circuit 56, for example, when the first motor 33 is decelerated under control of the inverter circuit 56.

[0061] The electromagnetic brake controller 74 controls the electromagnetic brake 37. Specifically, the electromagnetic brake controller 74 controls the operation of the electromagnetic brake 37 to brake the first motor 33. Furthermore, the electromagnetic brake controller 74 controls the electromagnetic brake 37 to brake the first motor 33 in an emergency stop. That is, when the user presses down the emergency stop button 52, the electromagnetic brake controller 74 receives an emergency stop signal from the emergency stop button 52 and places the electromagnetic brake 37 in a de-energized state. As a result, the first motor 33 is braked by the electromagnetic brake 37 in addition to the dynamic brake by the regenerative circuit 55.

[0062] The end effector controller 75 controls the end effector 35. Specifically, the end effector controller 75 controls the operation of the end effector 35 based on the program in the memory 42.

[0063] The end effector controller 75 may control the end effector 35 to stop in the event of an emergency stop. Specifically, when the user presses down the emergency stop button 52, the end effector controller 75 may stop the operation of the end effector 35 upon receiving an emergency stop signal from the emergency stop button 52.

[0064] The cooperative controller 76 communicates with a cooperative controller 176 (described later) of the second control device 5 via the communication module 53 to coordinate the operation of the robot arm 20 with the operation of the transport device 3. Specifically, the cooperative controller 76, together with the cooperative controller 176 (described later), synchronizes the operation of the robot arm 20 with the operation of the transport device 3. As a result, for example, the first control device 4 and the second control device 5 apply dynamic brakes to the first motor 33 and the second motor 121 in cooperation with each other during an emergency stop.

[0065] (Configuration of second control device 5) 7 is a block diagram showing the configuration of the second control device 5. The second control device 5 has a processor 141 that performs overall control of the transport device 3, a storage device 142 that stores various programs and various data, and a memory 143. The second control device 5 further has a converter circuit 151, an emergency stop button 152, a communication module 153, a regeneration circuit 155, and a plurality of inverter circuits 156.

[0066] The storage unit 142 stores various programs and various data executed by the processor 141. The storage unit 142 is formed of a non-volatile memory, a hard disk drive (HDD), a solid state drive (SSD), etc. The memory 143 temporarily stores data, etc. For example, the memory 143 is formed of a volatile memory.

[0067] The processor 141 performs various types of arithmetic processing. Specifically, the processor 141 realizes various functions by reading out a program from the storage device 142 into the memory 143 and expanding the program. For example, the processor 141 is formed of a processor such as a CPU (Central Processing Unit).

[0068] The processor 141 is connected to a converter circuit 151, an emergency stop button 152, and a communication module 153. Although not shown for convenience, the processor 141 is also connected to a regeneration circuit 155 and an inverter circuit 156.

[0069] A regenerative circuit 155 and a plurality of inverter circuits 156 are connected to the converter circuit 151. Each inverter circuit 156 is connected to a second motor 121. Specifically, one regenerative circuit 155 and two inverter circuits 156 are connected to the converter circuit 151. The converter circuit 151 converts AC power supplied from a power source into DC power. The regenerative circuit 155 consumes regenerative energy generated in the second motor 121. The inverter circuit 156 converts DC power into AC power and outputs the AC power to the second motor 121. An encoder 136 and an electromagnetic brake 137 are attached to the second motor 121a. Although not shown, an encoder 136 and an electromagnetic brake 137 are also attached to the other second motor 121b.

[0070] The emergency stop button 152 outputs an emergency stop signal when pressed by a user in the event of an emergency stop. The communication module 153 has a hub, a communication cable, etc., and connects the second control device 5 to the first control device 4 so that they can communicate with each other.

[0071] FIG. 8 is a circuit diagram showing the converter circuit 151, the regenerative circuit 155, and the inverter circuit 156 of the second control device 5.

[0072] All the inverter circuits 156 are connected in parallel to the converter circuit 151. A capacitor 154 is connected between the converter circuit 151 and the inverter circuit 156. The capacitor 154 is connected in parallel to the converter circuit 151 and the inverter circuit 156. The regeneration circuit 155 is connected in parallel to the converter circuit 151 and the inverter circuit 156 between the converter circuit 151 and the inverter circuit 156, more specifically, between the capacitor 154 and the inverter circuit 156.

[0073] The converter circuit 151 includes, for example, a bridge diode. The converter circuit 151 is controlled by the processor 141. Specifically, the on / off of the converter circuit 151 is controlled by the processor 141. As a result, the supply or cut-off of power to the inverter circuit 156 is switched.

[0074] The configuration of the inverter circuit 156 is similar to the configuration of the inverter circuit 56 of the first control device 4 shown in FIG. 5. That is, the inverter circuit 156 has six transistors as switching elements and free wheel diodes connected in parallel to each of the six transistors. Each switching element of the inverter circuit 156 is controlled by the processor 141. Specifically, the on / off of each switching element of the inverter circuit 156 is controlled by the processor 141. As a result, the rotation speed of the second motor 121 is controlled by the inverter circuit 156.

[0075] For example, when the second motor 121 is decelerated by control using the inverter circuit 156, the capacitor 154 can store the voltage that increases in the inverter circuit 156 as energy.

[0076] The regenerative circuit 155 has a second regenerative resistor 161, a switch 162, and a switch controller 163. The second regenerative resistor 161 is connected in parallel to the converter circuit 151 and the inverter circuit 156 between the converter circuit 151 and the inverter circuit 156, more specifically, between the capacitor 154 and the inverter circuit 156. The switch 162 is connected in series to the second regenerative resistor 161.

[0077] The second regenerative resistor 161 consumes regenerative energy generated in the second motor 121 due to the rotation of the second motor 121. The second regenerative resistor 161 is an example of a "moving body regenerative resistor".

[0078] The switch 162 is configured to be switchable between a connection state in which the second regenerative resistor 161 is connected to the second motor 121 and a non-connection state in which the second regenerative resistor 161 is disconnected from the second motor 121. The switch 162 is configured, for example, by a transistor.

[0079] The switch controller 163 sets the switch 162 to a connected state during an emergency stop. The switch controller 163 is controlled by the processor 141. When the switch 162 is in a connected state, the second regenerative resistor 161 is connected to the second motor 121, and the second regenerative resistor 161 consumes the regenerative energy of the second motor 121. In this manner, the regenerative circuit 155 is used to apply dynamic braking to the second motor 121 during an emergency stop. Furthermore, when the switch 162 is in a connected state, the second regenerative resistor 161 is also connected to the capacitor 154, and the second regenerative resistor 161 also consumes the energy stored in the capacitor 154.

[0080] The switch controller 163 may keep the switch 162 in the connected state even during normal operation, particularly when the second motor 121 is decelerating. This allows the second regenerative resistor 161 to consume energy associated with the voltage rising in the inverter circuit 156, for example, when the second motor 121 is decelerated under control by the inverter circuit 156.

[0081] 9 is a block diagram showing functions of the processor 141 of the second control device 5. The processor 141 has a converter circuit controller 171, an inverter circuit controller 172, a regenerative circuit controller 173, an electromagnetic brake controller 174, and a cooperative controller 176 as functional blocks.

[0082] The converter circuit controller 171 controls the converter circuit 151. For example, the converter circuit controller 171 controls the converter circuit 151 so as to stabilize the voltage output from the converter circuit 151. Furthermore, the converter circuit controller 171 controls the converter circuit 151 so as to cut off the power from the converter circuit 151 to the inverter circuit 156 in the event of an emergency stop. That is, when the user presses down the emergency stop button 152, the converter circuit controller 171 receives an emergency stop signal from the emergency stop button 152 and cuts off the power from the converter circuit 151. As a result, the converter circuit controller 171 cuts off the power supplied to the second motor 121 in the event of an emergency stop.

[0083] The inverter circuit controller 172 controls the inverter circuit 156. Specifically, the inverter circuit controller 172 controls the on / off of each switching element of the inverter circuit 156 based on the program in the memory 142. The inverter circuit controller 172 controls the rotation speed of the second motor 121 based on the rotation position of the second motor 121 detected by the encoder 136.

[0084] The inverter circuit controller 172 may execute control for decelerating and stopping the second motor 121 in the event of an emergency stop. Specifically, when the user presses down the emergency stop button 152, the inverter circuit controller 172 may execute control for decelerating and stopping the second motor 121 upon receiving an emergency stop signal from the emergency stop button 152.

[0085] The regenerative circuit controller 173 controls the regenerative circuit 155. Specifically, the regenerative circuit controller 173 controls the switch controller 163 to connect the switch 162 during an emergency stop. In other words, when the user presses down the emergency stop button 152, the regenerative circuit controller 173 receives an emergency stop signal from the emergency stop button 152 and controls the switch controller 163 to connect the switch 162. As a result, the regenerative circuit controller 173 applies dynamic braking to the second motor 121 during an emergency stop.

[0086] The regenerative circuit controller 173 may control the switch controller 163 to keep the switch 162 in the connected state even during normal operation, particularly when the second motor 121 is decelerating. This allows the second regenerative resistor 161 to consume energy associated with the voltage rising in the inverter circuit 156, for example, when the second motor 121 is decelerated by control using the inverter circuit 156.

[0087] The electromagnetic brake controller 174 controls the electromagnetic brake 137. Specifically, the electromagnetic brake controller 174 controls the operation of the electromagnetic brake 137 to brake the second motor 121. Furthermore, the electromagnetic brake controller 174 controls the electromagnetic brake 137 so as to brake the second motor 121 in the event of an emergency stop. That is, when the user presses down the emergency stop button 152, the electromagnetic brake controller 174 receives an emergency stop signal from the emergency stop button 152 and places the electromagnetic brake 137 in a non-excited state. As a result, the second motor 121 is braked by the electromagnetic brake 137 in addition to the dynamic brake by the regenerative circuit 155.

[0088] The cooperative controller 176 communicates with the cooperative controller 76 of the first control device 4 via the communication module 153 to coordinate the operation of the robot arm 20 with the operation of the transport device 3. Specifically, the cooperative controller 176 synchronizes the operation of the robot arm 20 with the operation of the transport device 3 together with the cooperative controller 76. As a result, for example, the first control device 4 and the second control device 5 apply dynamic brakes to the first motor 33 and the second motor 121 in cooperation with each other during an emergency stop.

[0089] (Control of the conveying device 3 by the second control device 5) Next, a description will be given of the control of the transport device 3 by the second control device 5. The control of the robot arm 20 by the first control device 4 is similar, and therefore a description thereof will be omitted.

[0090] FIG. 10 is a schematic time chart showing the control of the transport device 3 by the second control device 5 during normal operation. At time t1, the inverter circuit controller 172 starts to control the rotation speed of the second motor 121. That is, the inverter circuit controller 172 starts to control the speed of the shuttle bar 113 of the transport device 3. Then, by controlling the second motor 121, the speed of the shuttle bar 113 is accelerated between time t1 and time t2, and the speed of the shuttle bar 113 is kept constant between time t2 and time t3. The speed of the shuttle bar 113 is decelerated between time t3 and time t4. At time t4, the electromagnetic brake controller 174 activates the electromagnetic brake 137 to brake the second motor 121. As a result, the second motor 121 stops after time t4, and the shuttle bar 113 also stops. The speed of the shuttle bar 113 is controlled by the cooperative controller 176 based on the operation of the robot arm 20.

[0091] 11 is a schematic time chart showing the control of the transport device 3 by the second control device 5 during an emergency stop. At time t1, the inverter circuit controller 172 starts controlling the rotation speed of the second motor 121. That is, the inverter circuit controller 172 starts controlling the speed of the shuttle bar 113 of the transport device 3. Then, by controlling the second motor 121, the speed of the shuttle bar 113 is accelerated between time t1 and time t2, and the speed of the shuttle bar 113 is maintained constant between time t2 and time t3.

[0092] When the emergency stop button 152 is pressed down during an emergency stop at time t3, the regeneration circuit controller 173 receives an emergency stop signal from the emergency stop button 152 and applies dynamic braking to the second motor 121. In this example, in addition to the dynamic braking, the inverter circuit controller 172 executes control to decelerate and stop the second motor 121. This causes the speed of the shuttle bar 113 to decelerate between time t3 and time t5. In FIG. 11, the deceleration of the shuttle bar 113 during normal operation is shown by a dashed line for comparison with the speed of the shuttle bar 113. Thus, the time t5 of deceleration during an emergency stop is earlier than the time t4 of deceleration during normal operation.

[0093] (Cooperative control between the first control device 4 and the second control device 5) Next, the cooperative control between the first control device 4 and the second control device 5 will be described.

[0094] The cooperative controller 76 of the first control device 4 and the cooperative controller 176 of the second control device 5 transmit and receive signals to each other via the communication modules 53, 153, respectively, to coordinate the operation of the robot arm 20 and the operation of the transport device 3. The control in this case is a so-called distributed control of cooperative control.

[0095] Specifically, the cooperative controller 76 transmits information such as the attitude and position of the robot arm 20 as a signal to the cooperative controller 176. The cooperative controller 176 controls the operation of the transport device 3 based on the signal received from the cooperative controller 76. Meanwhile, the cooperative controller 176 transmits information such as the position of the shuttle bar 113 of the transport device 3 as a signal to the cooperative controller 76. The cooperative controller 76 controls the operation of the robot arm 20 based on the signal received from the cooperative controller 176. This allows the robot arm 20 and the transport device 3 to operate without interfering with each other. For example, the transport device 3 can transport the workpiece W placed on the shuttle bar 113 to the working area of ​​the robot arm 20 so that the workpiece W does not interfere with the robot arm 20.

[0096] Next, in the event of an emergency stop, for example, when a user presses down the emergency stop button 52 of the first control device 4, the cooperative controller 76 receives an emergency stop signal from the emergency stop button 52 and transmits the emergency stop signal to the converter circuit controller 71, the inverter circuit controller 72, the regenerative circuit controller 73, the electromagnetic brake controller 74, and the end effector controller 75. As a result, the converter circuit controller 71, the inverter circuit controller 72, the regenerative circuit controller 73, the electromagnetic brake controller 74, and the end effector controller 75 execute control in the event of an emergency stop.

[0097] Furthermore, the cooperative controller 76 receives an emergency stop signal from the emergency stop button 52 and transmits the emergency stop signal to the cooperative controller 176. The cooperative controller 176 receives an emergency stop signal from the cooperative controller 76 and transmits the emergency stop signal to the converter circuit controller 171, the inverter circuit controller 172, the regenerative circuit controller 173, and the electromagnetic brake controller 174. As a result, the converter circuit controller 171, the inverter circuit controller 172, the regenerative circuit controller 173, and the electromagnetic brake controller 174 execute control at the time of emergency stop.

[0098] As a result, the execution of control during an emergency stop by the converter circuit controller 71, inverter circuit controller 72, regenerative circuit controller 73, electromagnetic brake controller 74 and end effector controller 75 of the first control device 4 is synchronized with the execution of control during an emergency stop by the converter circuit controller 171, inverter circuit controller 172, regenerative circuit controller 173 and electromagnetic brake controller 174 of the second control device 5.

[0099] On the other hand, when the user presses down the emergency stop button 152 of the second control device 5, the cooperative controller 176 receives an emergency stop signal from the emergency stop button 152 and transmits the emergency stop signal to the converter circuit controller 171, the inverter circuit controller 172, the regenerative circuit controller 173, and the electromagnetic brake controller 174. As a result, the converter circuit controller 171, the inverter circuit controller 172, the regenerative circuit controller 173, and the electromagnetic brake controller 174 execute control at the time of emergency stop.

[0100] Furthermore, the cooperative controller 176 receives an emergency stop signal from the emergency stop button 152 and transmits the emergency stop signal to the cooperative controller 76. The cooperative controller 76 receives an emergency stop signal from the cooperative controller 176 and transmits the emergency stop signal to the converter circuit controller 71, the inverter circuit controller 72, the regenerative circuit controller 73, the electromagnetic brake controller 74, and the end effector controller 75. As a result, the converter circuit controller 71, the inverter circuit controller 72, the regenerative circuit controller 73, the electromagnetic brake controller 74, and the end effector controller 75 execute control at the time of emergency stop.

[0101] As a result, the execution of control during an emergency stop by the converter circuit controller 71, inverter circuit controller 72, regenerative circuit controller 73, electromagnetic brake controller 74 and end effector controller 75 of the first control device 4 is synchronized with the execution of control during an emergency stop by the converter circuit controller 171, inverter circuit controller 172, regenerative circuit controller 173 and electromagnetic brake controller 174 of the second control device 5.

[0102] Therefore, in the event of an emergency stop, the first control device 4 and the second control device 5 can cooperate to apply dynamic brakes to the first motor 33 and the second motor 121. For example, in the event of an emergency stop, by synchronizing the stopping of the transfer device 3 with the stopping of the robot arm 20, the transfer device 3 and the robot arm 20 can be stopped so that the workpiece W placed on the shuttle bar 113 does not interfere with the robot arm 20.

[0103] According to the above-described braking system 100, the first control device 4 and the second control device 5 apply dynamic brakes in cooperation with each other to the first motor 33 and the second motor 121 during an emergency stop. Therefore, the robot arm 20 and the transport device 3 can be stably braked during an emergency stop.

[0104] In detail, if the robot arm 20 and the transport device 3 are braked separately in an emergency stop, for example, the braking timing of the robot arm 20 and the braking timing of the transport device 3 may differ, and there is a risk that the workpiece W placed on the shuttle bar 113 of the transport device 3 may interfere with the robot arm 20. In contrast, if the robot arm 20 and the transport device 3 are braked in coordination in an emergency stop, it is possible to prevent the workpiece W placed on the shuttle bar 113 from interfering with the robot arm 20. In this way, when the robot arm 20 and the transport device 3 work together, it is possible to prevent the robot arm 20 and the transport device 3 from interfering with each other in an emergency stop, and stable braking can be achieved in an emergency stop.

[0105] Furthermore, the first control device 4 and the second control device 5 cooperate to apply dynamic brakes to the first motor 33 and the second motor 121. This allows the first control device 4 and the second control device 5 to brake the first motor 33 and the second motor 121 through cooperative control using distributed control. Therefore, even if one of the first control device 4 and the second control device 5 does not operate, the other control device can brake the first motor 33 and the second motor 121.

[0106] Moreover, the first control device 4 has a regenerative circuit 55 including a first regenerative resistor 61 that consumes the regenerative energy generated in the first motor 33, and the second control device 5 has a regenerative circuit 155 including a second regenerative resistor 161 that consumes the regenerative energy generated in the second motor 121. This allows dynamic braking to be applied simply by providing the regenerative resistors 61, 161, making it easy to control the dynamic braking. Furthermore, the first regenerative resistor 61 and the second regenerative resistor 161 allow the regenerative energy of the first motor 33 and the regenerative energy of the second motor 121 to be consumed separately, reducing the load applied to the first regenerative resistor 61 and the second regenerative resistor 161, thereby improving the durability of the first regenerative resistor 61 and the second regenerative resistor 161.

[0107] Moreover, the regenerative circuit 55 includes a switch 62 and a switch controller 63, and the regenerative circuit 155 includes a switch 162 and a switch controller 163. As a result, during an emergency stop, the regenerative resistor 6 is connected to the first motor 33, and the regenerative resistor 161 is connected to the second motor 121, so that dynamic braking can be applied to each of the motors 33, 121.

[0108] Furthermore, the first regenerative resistor 61 is connected between the converter circuit 51 and the inverter circuit 56, in parallel with the converter circuit 51 and the inverter circuit 56. As a result, when the first motor 33 is decelerated under control by the inverter circuit 56, the energy associated with the voltage rising in the inverter circuit 56 can be consumed by the first regenerative resistor 61. In this way, the first regenerative resistor 61 can be used both for dynamic braking and for preventing a voltage rise during deceleration.

[0109] Furthermore, the second regenerative resistor 161 is connected between the converter circuit 151 and the inverter circuit 156 in parallel with the converter circuit 151 and the inverter circuit 156. As a result, when the second motor 121 is decelerated by the inverter circuit 156, the energy associated with the voltage rising in the inverter circuit 156 can be consumed by the second regenerative resistor 161. In this way, the second regenerative resistor 161 can be used both for dynamic braking and for preventing a voltage rise during deceleration.

[0110] Moreover, the moving device is a transport device 3 that transports a workpiece W. Since the robot arm 20 and the transport device 3 can be stably braked in the event of an emergency stop, it is possible to prevent interference between the workpiece W being transported by the transport device 3 and the robot arm 20 in the event of an emergency stop.

[0111] Variation 1 12 is a block diagram showing the configuration of the control device 6 of the braking system 200 according to the first modification. The braking system 200 according to the first modification differs from the braking system 100 according to the embodiment in that it has a common control device 6 instead of separate first control device 4 and second control device 5. The following mainly describes the configuration of the braking system 200 according to the first modification that differs from the braking system 100 according to the embodiment. Note that in the braking system 200 according to the first modification, the same reference numerals as those in the braking system 100 according to the embodiment have the same configuration as the braking system 100 according to the embodiment, and therefore description thereof will be omitted.

[0112] In the braking system 200 according to the first modification, the control device 6 is provided in common to the robot arm 20 and the transport device 3. In other words, the control device 6 is provided in common to the first motor 33 and the second motor 121.

[0113] Specifically, the control device 6 has a processor 241 that performs overall control of the robot arm 20 and the transport device 3, a storage device 242 that stores various programs and various data, and a memory 243. The second control device 5 further has a converter circuit 251, an emergency stop button 252, a communication module 253, a regenerative circuit 255, a plurality of first inverter circuits 56A, and a plurality of second inverter circuits 156A. In the control device 6, the second inverter circuit 156A and the second motor 121 may be called an "external shaft." The first inverter circuit 56A is an example of a "robot inverter circuit." The second inverter circuit 156A is an example of a "mobile body inverter circuit."

[0114] The storage unit 242 stores various programs and various data executed by the processor 241. The storage unit 242 is formed of a non-volatile memory, a hard disk drive (HDD), a solid state drive (SSD), etc. The memory 243 temporarily stores data, etc. For example, the memory 243 is formed of a volatile memory.

[0115] The processor 241 performs various types of arithmetic processing. Specifically, the processor 241 realizes various functions by reading out a program from the storage unit 242 into the memory 243 and expanding the program. For example, the processor 241 is formed of a processor such as a CPU (Central Processing Unit).

[0116] The processor 241 is connected to a converter circuit 251 and an emergency stop button 252. Although not shown for convenience, the processor 241 is also connected to a regeneration circuit 255, a first inverter circuit 56A, and a second inverter circuit 156A.

[0117] The converter circuit 251 is connected to a regenerative circuit 255, a plurality of first inverter circuits 56A, and a plurality of second inverter circuits 156A. The first motors 33 are connected to the first inverter circuits 56A. The second motors 121 are connected to the second inverter circuits 156A. Specifically, the converter circuit 251 is connected to one regenerative circuit 255, six first inverter circuits 56A, and two second inverter circuits 156A. The converter circuit 251 converts AC power supplied from a power source into DC power. The regenerative circuit 255 consumes regenerative energy generated in the first motor 33 and the second motor 121. The first inverter circuit 56A converts DC power into AC power and outputs the AC power to the first motor 33. The second inverter circuit 156A converts DC power into AC power and outputs the AC power to the second motor 121. An encoder 36 and an electromagnetic brake 37 shown in Fig. 4 are attached to each of the first motors 33. An encoder 136 and an electromagnetic brake 137 shown in Fig. 7 are attached to each of the second motors 121.

[0118] The emergency stop button 252 outputs an emergency stop signal when pressed by the user in the event of an emergency stop.

[0119] FIG. 13 is a circuit diagram showing the converter circuit 251, the regenerative circuit 255, the first inverter circuit 56A, and the second inverter circuit 156A of the control device 6. As shown in FIG.

[0120] All the first inverter circuits 56A are connected in parallel to the converter circuit 251. All the second inverter circuits 156A are connected in parallel to the first inverter circuit 56A. A capacitor 254 is connected between the converter circuit 251 and the first and second inverter circuits 56A and 156A. The capacitor 254 is connected in parallel to the converter circuit 251 and the first and second inverter circuits 56A and 156A. The regenerative circuit 255 is connected in parallel to the converter circuit 251 and the first and second inverter circuits 56A and 156A between the converter circuit 251 and the first and second inverter circuits 56A and 156A, more specifically, between the capacitor 254 and the first and second inverter circuits 56A and 156A.

[0121] The converter circuit 251 includes, for example, a bridge diode. The converter circuit 251 is controlled by the processor 241. Specifically, the on / off of the converter circuit 251 is controlled by the processor 241. This switches between supplying and cutting off power to the first inverter circuit 56A and the second inverter circuit 156A.

[0122] The configuration of the first inverter circuit 56A and the second inverter circuit 156A is the same as the configuration of the inverter circuit 56 of the first control device 4 shown in FIG. 5. That is, the first inverter circuit 56A and the second inverter circuit 156A each have six transistors as switching elements and a free wheel diode connected in parallel to each of the six transistors. Each switching element of the first inverter circuit 56A and the second inverter circuit 156A is controlled by the processor 241. Specifically, the on / off of each switching element of the first inverter circuit 56A and the second inverter circuit 156A is controlled by the processor 241. As a result, the first motor 33 is controlled via the first inverter circuit 56A, and the second motor 121 is controlled via the second inverter circuit 156A.

[0123] For example, when the first motor 33 is decelerated by control via the first inverter circuit 56A, the capacitor 254 can store the voltage rising in the first inverter circuit 56A as energy. Furthermore, when the second motor 121 is decelerated by control via the second inverter circuit 156A, the capacitor 254 can store the voltage rising in the second inverter circuit 156A as energy.

[0124] The regenerative circuit 255 has a regenerative resistor 261, a switch 262, and a switch controller 263. The regenerative resistor 261 is connected in parallel with the converter circuit 251 and the first inverter circuit 56A and the second inverter circuit 156A between the converter circuit 251 and the first inverter circuit 56A and the second inverter circuit 156A, more specifically, between the capacitor 254 and the first inverter circuit 56A and the second inverter circuit 156A. The switch 262 is connected in series with the regenerative resistor 261.

[0125] The regenerative resistor 261 consumes regenerative energy generated in the first motor 33 due to the rotation of the first motor 33, and consumes regenerative energy generated in the second motor 121 due to the rotation of the second motor 121. In other words, the regenerative resistor 261 is provided in common to the first motor 33 and the second motor 121.

[0126] The switch 262 is configured to be switchable between a connection state in which the regenerative resistor 261 is connected to the first motor 33 and the second motor 121, and a non-connection state in which the regenerative resistor 261 is disconnected from the first motor 33 and the second motor 121. The switch 262 is configured, for example, by a transistor.

[0127] The switch controller 263 sets the switch 262 to a connected state during an emergency stop. The switch controller 263 is controlled by the processor 241. When the switch 262 is in a connected state, the regenerative resistor 261 is connected to the first motor 33 and the second motor 121, and the regenerative resistor 261 consumes the regenerative energy of the first motor 33 and the second motor 121. In this manner, the regenerative circuit 255 is used to apply dynamic braking to the first motor 33 and the second motor 121 during an emergency stop. Furthermore, when the switch 262 is in a connected state, the regenerative resistor 261 is also connected to the capacitor 254, and the regenerative resistor 261 also consumes the energy stored in the capacitor 254.

[0128] The switch controller 263 may keep the switch 262 in the connected state even during normal operation, particularly when the first motor 33 or the second motor 121 is decelerating. Thereby, for example, when the first motor 33 is decelerated under control by the first inverter circuit 56A, the energy associated with the voltage rising in the first inverter circuit 56A can be consumed by the regenerative resistor 261. Alternatively, when the second motor 121 is decelerated under control by the second inverter circuit 156A, the energy associated with the voltage rising in the second inverter circuit 156A can be consumed by the regenerative resistor 261.

[0129] 14 is a block diagram showing functions of the processor 241 of the control device 6. The processor 241 has a converter circuit controller 271, a first inverter circuit controller 272A, a second inverter circuit controller 272B, a regenerative circuit controller 273, a first electromagnetic brake controller 274A, a second electromagnetic brake controller 274B, and an end effector controller 275 as functional blocks.

[0130] The converter circuit controller 271 controls the converter circuit 251. For example, the converter circuit controller 271 controls the converter circuit 251 so as to stabilize the voltage output from the converter circuit 251. Furthermore, the converter circuit controller 271 controls the converter circuit 251 so as to cut off the power from the converter circuit 251 to the first inverter circuit 56A and the second inverter circuit 156A at the time of emergency stop. That is, when the user presses down the emergency stop button 252, the converter circuit controller 271 receives an emergency stop signal from the emergency stop button 252 and cuts off the power from the converter circuit 251. As a result, the converter circuit controller 271 cuts off the power supplied to the first motor 33 and the second motor 121 at the time of emergency stop.

[0131] The first inverter circuit controller 272A controls the first inverter circuit 56A. Specifically, the first inverter circuit controller 272A controls the on / off of each switching element of the first inverter circuit 56A based on the program in the memory 242. The first inverter circuit controller 272A controls the rotation speed of the first motor 33 based on the rotation position of the first motor 33 detected by the encoder 36.

[0132] The first inverter circuit controller 272A may execute control for decelerating and stopping the first motor 33 in the event of an emergency stop. Specifically, when the user presses down the emergency stop button 252, the first inverter circuit controller 272A may execute control for decelerating and stopping the first motor 33 upon receiving an emergency stop signal from the emergency stop button 252.

[0133] The second inverter circuit controller 272B controls the second inverter circuit 156A. Specifically, the second inverter circuit controller 272B controls the on / off of each switching element of the second inverter circuit 156A based on the program in the memory 242. The second inverter circuit controller 272B controls the rotation speed of the second motor 121 based on the rotation position of the second motor 121 detected by the encoder 136.

[0134] The second inverter circuit controller 272B may execute control for decelerating and stopping the second motor 121 in the event of an emergency stop. Specifically, when the user presses down the emergency stop button 252, the second inverter circuit controller 272B may execute control for decelerating and stopping the second motor 121 upon receiving an emergency stop signal from the emergency stop button 252.

[0135] The regeneration circuit controller 273 controls the regeneration circuit 255. Specifically, the regeneration circuit controller 273 controls the switch controller 263 to connect the switch 262 during an emergency stop. In other words, when the user presses down the emergency stop button 252, the regeneration circuit controller 273 receives an emergency stop signal from the emergency stop button 252 and controls the switch controller 263 to connect the switch 262. As a result, the regeneration circuit controller 273 applies dynamic brakes to the first motor 33 and the second motor 121 during an emergency stop.

[0136] The regenerative circuit controller 273 may control the switch controller 263 to keep the switch 262 in the connected state even during normal operation, particularly when the first motor 33 or the second motor 121 is decelerating. This allows, for example, when the first motor 33 is decelerated under control by the first inverter circuit 56A, the energy associated with the voltage rising in the first inverter circuit 56A to be consumed by the regenerative resistor 261. Alternatively, when the second motor 121 is decelerated under control by the second inverter circuit 156A, the energy associated with the voltage rising in the second inverter circuit 156A can be consumed by the regenerative resistor 261.

[0137] The first electromagnetic brake controller 274A controls the electromagnetic brake 37 of the first motor 33. Specifically, the first electromagnetic brake controller 274A controls the operation of the electromagnetic brake 37 to brake the first motor 33. Furthermore, the first electromagnetic brake controller 274A controls the electromagnetic brake 37 so as to brake the first motor 33 in an emergency stop. That is, when the user presses down the emergency stop button 252, the first electromagnetic brake controller 274A receives an emergency stop signal from the emergency stop button 252 and places the electromagnetic brake 37 in a non-excited state. As a result, the first motor 33 is braked by the electromagnetic brake 37 in addition to the dynamic brake by the regenerative circuit 255.

[0138] The second electromagnetic brake controller 274B controls the electromagnetic brake 137 of the second motor 121. Specifically, the second electromagnetic brake controller 274B controls the operation of the electromagnetic brake 137 to brake the second motor 121. Furthermore, the second electromagnetic brake controller 274B controls the electromagnetic brake 137 so as to brake the second motor 121 in the event of an emergency stop. That is, when the user presses down the emergency stop button 252, the second electromagnetic brake controller 274B receives an emergency stop signal from the emergency stop button 252 and places the electromagnetic brake 137 in a non-excited state. As a result, the second motor 121 is braked by the electromagnetic brake 137 in addition to the dynamic brake by the regenerative circuit 255.

[0139] Next, the control of the robot arm 20 and the transport device 3 by the control device 6 will be described.

[0140] The control device 6 coordinates the operation of the robot arm 20 with the operation of the transport device 3. The control in this case is a so-called centralized control of cooperative control.

[0141] Specifically, during normal operation of the robot arm 20 and the transport device 3, the first inverter circuit controller 272A controls the rotation speed of the first motor 33 to operate the robot arm 20, and the second inverter circuit controller 272B controls the rotation speed of the second motor 121 to operate the transport device 3. At this time, the control device 6 controls the robot arm 20 and the transport device 3 so that they do not interfere with each other.

[0142] In the event of an emergency stop of the robot arm 20 and the conveying device 3, the converter circuit controller 271, the first inverter circuit controller 272A, the second inverter circuit controller 272B, the regenerative circuit controller 273, the first electromagnetic brake controller 274A, the second electromagnetic brake controller 274B and the end effector controller 275 execute control in the event of an emergency stop.

[0143] In particular, the regenerative circuit controller 273 applies dynamic brakes to the first motor 33 and the second motor 121 upon receiving an emergency stop signal from the emergency stop button 252. That is, the control device 6 applies dynamic brakes to the first motor 33 and the second motor 121 in coordination with each other during an emergency stop. This allows the robot arm 20 and the transport device 3 to be braked in coordination with each other during an emergency stop. Therefore, the robot arm 20 and the transport device 3 can be braked stably during an emergency stop. For example, when the robot arm 20 and the transport device 3 work together, interference between the robot arm 20 and the transport device 3 can be prevented during an emergency stop.

[0144] According to the braking system 200 of the first modification, the control device 6 is provided in common to the first motor 33 and the second motor 121. This allows the control device 6 to brake the first motor 33 and the second motor 121 through cooperative control using centralized control. This allows the number of control devices 6 to be reduced, making the manufacture of the control devices 6 easier.

[0145] Moreover, the regenerative resistor 261 is provided in common to the first motor 33 and the second motor 121. This makes it possible to reduce the number of regenerative resistors 261 and to downsize the control device 6. Furthermore, even if the cooperative controllers 76, 176 of the above embodiment are not provided, dynamic braking can be applied to the first motor 33 and the second motor 121 in cooperation with each other during an emergency stop.

[0146] Moreover, the regenerative resistor 261 is connected in parallel to the converter circuit 251, the first inverter circuit 56A, and the second inverter circuit 156A between the converter circuit 251 and the first inverter circuit 56A and the second inverter circuit 156A. As a result, for example, when the first motor 33 is decelerated under the control of the first inverter circuit 56A, the regenerative resistor 261 can consume energy associated with the voltage rising in the first inverter circuit 56A. Furthermore, when the second motor 121 is decelerated under the control of the second inverter circuit 156A, the regenerative resistor 261 can consume energy associated with the voltage rising in the second inverter circuit 156A. In this way, the regenerative resistor 261 can be used for both the action of dynamic braking and the prevention of a voltage rise during deceleration.

[0147] Incidentally, the description of the other configurations, operations, and effects will be omitted, but the description of the braking system 100 according to the embodiment can be used to describe the braking system 200 according to the first modified example.

[0148] Other Embodiments As described above, the above embodiment has been described as an example of the technology disclosed in this application. However, the technology in this disclosure is not limited to this, and can be applied to embodiments in which modifications, replacements, additions, omissions, etc. are appropriately performed. In addition, it is also possible to combine the components described in the above embodiment to form a new embodiment. In addition, among the components described in the attached drawings and detailed description, not only components essential for solving the problem but also components that are not essential for solving the problem in order to exemplify the technology may be included. Therefore, the fact that these non-essential components are described in the attached drawings and detailed description should not immediately lead to the determination that these non-essential components are essential.

[0149] An emergency stop refers to a case where the user operates the emergency stop button 152, but may also be a case where the robot arm 20 or the transport device 3 stops due to an abnormality such as a system error, a case where the power supply from the power source is cut off by a breaker, or a case where the converter circuit 51 is stopped in an emergency, etc. Even in such a case, the control devices 4, 5, and 6 receive an emergency stop signal and apply dynamic brakes to the first motor 33 and the second motor 121 in cooperation with each other.

[0150] The moving device is a transport device 3 including a shuttle bar 113, but it may be a transport device using a rotary table as a moving body, or may be a transport device that transports a robot arm 20.

[0151] The braking system 100 may have a plurality of moving devices. In this case, a control device may be provided for each moving device, and the operation of the robot arm 20 and each moving device may be coordinated by the control device of each moving device and the control device of the robot arm 20. Alternatively, the plurality of moving devices and the robot arm 20 may be controlled by a common control device.

[0152] The transport device 3 may be provided with a lifting device that supports and lifts the workpiece W. Specifically, the lifting device may be disposed in the second area Z2 in Fig. 1, and after the transport device 3 moves the workpiece W to the second area Z2, the lifting device may lift the workpiece W to separate it from the transport device 3. At this time, the robot arm 20 may weld to the workpiece W lifted by the lifting device.

[0153] The transport device 3 has two shuttle bars 113, but may have one or more than two shuttle bars 113. The transport device 3 has two second motors 121, but may have one or more than two second motors 121.

[0154] The robot arm 20 has a plurality of links 31 and a plurality of first motors 33, but may have one link 31 and one first motor 33 that drives the link 31.

[0155] The end effector 35 may be a welding device that performs welding other than arc welding. For example, the end effector 35 may be a welding device that performs spot welding, laser welding, or the like. Alternatively, the end effector 35 is not limited to a welding device. For example, the end effector 35 may be a device that performs drilling, grinding, polishing, painting, or the like.

[0156] The switch 62 of the regenerative circuit 55 of the first control device 4 is a transistor, but may be a mechanical relay. The same is true for the switch 162 of the regenerative circuit 155 of the second control device 5, and the switch 262 of the regenerative circuit 255 of the control device 6.

[0157] The first control device 4 and the second control device 5 each have an emergency stop button 52, 152, but it is sufficient to provide either one of them. In this case, one control device having the emergency stop button transmits an emergency stop signal to the other control device, and the first motor 33 and the second motor 121 cooperate to apply dynamic brakes. Alternatively, the first control device 4 and the second control device 5 each do not have the emergency stop buttons 52, 152, and may be provided with individual emergency stop buttons. In this case, the first control device 4 and the second control device 5 receive the emergency stop signal from the emergency stop button and cooperate to apply dynamic brakes to the first motor 33 and the second motor 121.

[0158] The braking systems 100, 200 apply dynamic braking to the first motor 33 and the second motor 121 using regenerative circuits 55, 155, 255 including regenerative resistors 61, 161, 261, but dynamic braking may also be applied to the first motor 33 and the second motor 121 by other methods.

[0159] For example, referring to FIG. 5, a short circuit may be formed in the inverter circuit 56 to apply dynamic braking to the first motor 33. Specifically, the inverter circuit controller 72 may short-circuit all three phases of the first motor 33 by turning off the transistors 57a to 57c (three upper arms) and turning on the transistors 57d to 57f (three lower arms) in the inverter circuit 56, thereby forming a short circuit. Alternatively, the inverter circuit controller 72 may short-circuit all three phases of the first motor 33 by turning on the transistors 57a to 57c and turning off the transistors 57d to 57f in the inverter circuit 56, thereby forming a short circuit. Alternatively, the inverter circuit controller 72 may short-circuit all three phases of the first motor 33 by turning on the transistors 57a, 57b, and 57f in the inverter circuit 56 and turning off the transistors 57c, 57d, and 57e in the inverter circuit 56, thereby forming a short circuit.

[0160] 5, as another method for applying the dynamic brake, the U phase (transistors 57a, 57d), the V phase (transistors 57b, 57e), and the W phase (transistors 57c, 57f) may be short-circuited via resistors by a switch such as a relay in the inverter circuit 56. This applies the dynamic brake to the first motor 33.

[0161] The functions performed by the components described herein may be implemented in circuitry or processing circuitry, including general purpose processors, application specific processors, integrated circuits, ASICs (Application Specific Integrated Circuits), a CPU (a Central Processing Unit), conventional circuits, and / or combinations thereof, programmed to perform the functions described. Processors include transistors and other circuits and are considered to be circuits or processing circuitry. A processor may be a programmable processor that executes a program stored in a memory.

[0162] In this specification, a circuit, unit, or means is hardware that is programmed to realize or performs the described functions, which may be any hardware disclosed in this specification or any hardware known to be programmed to realize or perform the described functions.

[0163] If the hardware is a processor considered to be a type of circuitry, the circuit, means, or unit is a combination of the hardware and software used to configure the hardware and / or processor.

[0164] [Aspects] The above-described embodiment is a specific example of the following aspects.

[0165] (Aspect 1) The braking system 100, 200 comprises a robot arm 20 having a link 31 and a first motor 33 (robot motor) that drives the link 31, a conveying device 3 (moving device) having a shuttle bar 113 (moving body) and a second motor 121 (moving body motor) that drives the shuttle bar 113, and control devices 4, 5, 6 that control the first motor 33 and the second motor 121, and the control devices 4, 5, 6 apply dynamic brakes in coordination with the first motor 33 and the second motor 121 in the event of an emergency stop.

[0166] According to this configuration, the control devices 4, 5, and 6 apply dynamic brakes to the first motor 33 and the second motor 121 in cooperation with each other in the event of an emergency stop. This allows the robot arm 20 and the transport device 3 to be braked in cooperation with each other in the event of an emergency stop. Therefore, the robot arm 20 and the transport device 3 can be braked stably in the event of an emergency stop. For example, when the robot arm 20 and the transport device 3 work together, interference between the robot arm 20 and the transport device 3 in the event of an emergency stop can be prevented.

[0167] (Aspect 2) In the braking system 100, 200 according to the first aspect, The control devices 4, 5, and 6 each have a regenerative circuit 55, 155, or 255 including a regenerative resistor 61, 161, or 261 that consumes regenerative energy generated in the first motor 33 and the second motor 121.

[0168] According to this configuration, the control devices 4, 5, and 6 have regenerative circuits 55, 155, and 255 including regenerative resistors 61, 161, and 261 that consume regenerative energy generated in the first motor 33 and the second motor 121. This makes it possible to apply dynamic brakes simply by providing the regenerative resistors 61, 161, and 261, making it easy to control the dynamic brakes.

[0169] (Aspect 3) In the braking system 100, 200 according to the first or second aspect, The regenerative circuit 55, 155, 255 includes a switch 62, 162, 262 that can be switched between a connected state in which the regenerative resistor 61, 161, 261 is connected to the first motor 33 and the second motor 121, and a non-connected state in which the regenerative resistor 61, 161, 261 is disconnected from the first motor 33 and the second motor 121, and a switch controller 63, 163, 263 that sets the switch 62, 162, 262 to the connected state during an emergency stop.

[0170] According to this configuration, the regenerative circuit 55, 155, 255 includes a switch 62, 162, 262 and a switch controller 63, 163, 263. This allows the regenerative resistor 61, 161, 261 to be connected to each motor 33, 121 during an emergency stop, thereby applying dynamic brakes to each motor 33, 121.

[0171] (Aspect 4) In the braking system 100 according to any one of the first to third aspects, The regenerative resistors 61, 161 include a first regenerative resistor 61 (robot regenerative resistor) that consumes the regenerative energy of the first motor 33, and a second regenerative resistor 161 (moving body regenerative resistor) that consumes the regenerative energy of the second motor 121.

[0172] According to this configuration, the regenerative resistors 61, 161 include a first regenerative resistor 61 that consumes the regenerative energy of the first motor 33, and a second regenerative resistor 161 that consumes the regenerative energy of the second motor 121. This allows the regenerative energy of the first motor 33 and the regenerative energy of the second motor 121 to be consumed separately, reducing the load applied to the first regenerative resistor 61 and the second regenerative resistor 161, and improving the durability of the first regenerative resistor 61 and the second regenerative resistor 161.

[0173] (Aspect 5) In the braking system 100 according to any one of the first to fourth aspects, The control devices 4, 5 include a first control device 4 (robot control device) that controls the first motor 33 and includes the first regenerative resistor 61, and a second control device 5 (mobile body control device) that controls the second motor 121 and includes the second regenerative resistor 161, and the first control device 4 and the second control device 5 apply dynamic braking to the first motor 33 and the second motor 121 in coordination during an emergency stop.

[0174] According to this configuration, the first control device 4 and the second control device 5 apply dynamic brakes in cooperation with each other to the first motor 33 and the second motor 121. This allows the first control device 4 and the second control device 5 to brake the first motor 33 and the second motor 121 by cooperative control using distributed control. Therefore, even if one of the first control device 4 and the second control device 5 does not operate, the first motor 33 and the second motor 121 can be braked by the other control device.

[0175] (Aspect 6) In the braking system 100 according to any one of the first to fifth aspects, The first control device 4 has a converter circuit 51 that converts AC power supplied from a power source into DC power, and an inverter circuit 56 that converts the DC power into AC power and outputs the AC power to the first motor 33, and the first regenerative resistor 61 is connected in parallel to the converter circuit 51 and the inverter circuit 56 between the converter circuit 51 and the inverter circuit 56.

[0176] According to this configuration, the first regenerative resistor 61 is connected between the converter circuit 51 and the inverter circuit 56, in parallel with the converter circuit 51 and the inverter circuit 56. As a result, when the first motor 33 is decelerated under control by the inverter circuit 56, the energy associated with the voltage rising in the inverter circuit 56 can be consumed by the first regenerative resistor 61. In this way, the first regenerative resistor 61 can be used both for dynamic braking and for preventing a voltage rise during deceleration.

[0177] (Aspect 7) In the braking system 100 according to any one of the first to sixth aspects, The second control device 5 has a converter circuit 151 that converts AC power supplied from a power source into DC power, and an inverter circuit 156 that converts the DC power into AC power and outputs the AC power to the second motor 121, and the second regenerative resistor 161 is connected in parallel to the converter circuit 151 and the inverter circuit 156 between the converter circuit 151 and the inverter circuit 156.

[0178] According to this configuration, the second regenerative resistor 161 is connected between the converter circuit 151 and the inverter circuit 156 in parallel with the converter circuit 151 and the inverter circuit 156. As a result, when the inverter circuit 156 decelerates the second motor 121, the energy associated with the voltage rising in the inverter circuit 156 can be consumed by the second regenerative resistor 161. In this way, the second regenerative resistor 161 can be used both for dynamic braking and for preventing a voltage rise during deceleration.

[0179] (Aspect 8) In the braking system 200 according to any one of the first to seventh aspects, The control device 6 is provided in common to the first motor 33 and the second motor 121 .

[0180] According to this configuration, the control device 6 is provided in common to the first motor 33 and the second motor 121. This allows the control device 6 to brake the first motor 33 and the second motor 121 through cooperative control using centralized control. This allows the number of control devices 6 to be reduced, making the manufacture of the control devices 6 easier.

[0181] (Aspect 9) In the braking system 200 according to any one of the first to eighth aspects, The regenerative resistor 261 is provided in common to the first motor 33 and the second motor 121 .

[0182] According to this configuration, the regenerative resistor 261 is provided in common to the first motor 33 and the second motor 121. This makes it possible to reduce the number of regenerative resistors 261, and thus the control device 6 can be made more compact.

[0183] (Aspect 10) In the braking system 200 according to any one of the first to ninth aspects, The control device 6 has a converter circuit 251 that converts AC power supplied from a power source into DC power, a first inverter circuit 56A (robot inverter circuit) that converts DC power into AC power and outputs the AC power to the first motor 33, and a second inverter circuit 156A (mobile body inverter circuit) that converts DC power into AC power and outputs the AC power to the second motor 121 and is connected in parallel to the first inverter circuit 56A, and the regenerative resistor 261 is connected in parallel to the converter circuit 251, the first inverter circuit 56A, and the second inverter circuit 156A between the converter circuit 251 and the first inverter circuit 56A and the second inverter circuit 156A.

[0184] According to this configuration, the regenerative resistor 261 is connected in parallel to the converter circuit 251, the first inverter circuit 56A, and the second inverter circuit 156A between the converter circuit 251 and the first inverter circuit 56A and the second inverter circuit 156A. As a result, for example, when the first motor 33 is decelerated under control by the first inverter circuit 56A, the regenerative resistor 261 can consume energy associated with the voltage rising in the first inverter circuit 56A. Furthermore, when the second motor 121 is decelerated under control by the second inverter circuit 156A, the regenerative resistor 261 can consume energy associated with the voltage rising in the second inverter circuit 156A. In this way, the regenerative resistor 261 can be used for both dynamic braking and avoiding a voltage rise during deceleration.

[0185] (Aspect 11) In the braking system 100, 200 according to any one of the first to tenth aspects, The moving device is a transport device 3 that transports the workpiece W.

[0186] According to this configuration, the moving device is the transport device 3 that transports the workpiece W. Since the robot arm 20 and the transport device 3 can be stably braked in the event of an emergency stop, it is possible to prevent interference between the workpiece W being transported by the transport device 3 and the robot arm 20 in the event of an emergency stop. [Explanation of symbols]

[0187] 100,200 Braking System 2. Robot 3. Transport equipment (moving equipment) 4. First control device (robot control device) 5. Second control device (mobile body control device) 6. Control device 20 Robot Arm 31 Links 33 First motor (robot motor) 51,151,251 Converter circuit 55,155,255 Regeneration circuit 56,156 Inverter circuit 56A 1st inverter circuit (robot inverter circuit) 156A Second inverter circuit (mobile inverter circuit) 61 1st regenerative resistor (robot regenerative resistor) 161 Second regenerative resistor (moving body regenerative resistor) 261 Regenerative resistor 62,162,262 Switches 63,163,263 Switch Controller 113 Shuttle Bar (Mobile) 121 Second motor (moving body motor) W work

Claims

1. a robot arm having a link and a robot motor that drives the link; A moving device having a moving body and a moving body motor that drives the moving body; a control device for controlling the robot motor and the moving body motor, The control device is a braking system that applies dynamic brakes to the robot motor and the moving body motor in coordination during an emergency stop.

2. 2. The braking system of claim 1, The control device is a braking system having a regenerative circuit including a regenerative resistor that consumes regenerative energy generated in the robot motor and the moving body motor.

3. 3. The braking system of claim 2, The regenerative circuit includes: a switch capable of switching between a connection state in which the regenerative resistor is connected to the robot motor and the moving body motor and a disconnection state in which the regenerative resistor is disconnected from the robot motor and the moving body motor; and a switch controller that sets the switch to the connected state during an emergency stop.

4. 3. The braking system of claim 2, The braking system includes a robot regenerative resistor that consumes regenerative energy of the robot motor, and a moving body regenerative resistor that consumes regenerative energy of the moving body motor.

5. 5. The braking system of claim 4, the control device includes a robot control device that controls the robot motor and includes the robot regenerative resistor, and a moving body control device that controls the moving body motor and includes the moving body regenerative resistor, The robot control device and the moving body control device are a braking system that applies dynamic brakes to the robot motor and the moving body motor in cooperation with each other in the event of an emergency stop.

6. 6. The braking system of claim 5, The robot control device includes: A converter circuit that converts AC power supplied from a power source into DC power; an inverter circuit that converts DC power into AC power and outputs the AC power to the robot motor; The robot regenerative resistor is connected between the converter circuit and the inverter circuit in parallel with the converter circuit and the inverter circuit.

7. 6. The braking system of claim 5, The mobile object control device includes: A converter circuit that converts AC power supplied from a power source into DC power; an inverter circuit that converts DC power into AC power and outputs the AC power to the moving body motor; A braking system in which the moving body regenerative resistor is connected between the converter circuit and the inverter circuit and in parallel with the converter circuit and the inverter circuit.

8. 3. The braking system of claim 2, The control device is a braking system provided in common for the robot motor and the moving body motor.

9. 9. The braking system of claim 8, The regenerative resistor is provided in common to the robot motor and the moving body motor.

10. 10. The braking system of claim 9, The control device includes: A converter circuit that converts AC power supplied from a power source into DC power; A robot inverter circuit that converts DC power into AC power and outputs the AC power to the robot motor; a moving body inverter circuit that converts DC power into AC power, outputs the AC power to the moving body motor, and is connected in parallel to the robot inverter circuit; The regenerative resistor is connected between the converter circuit and the robot inverter circuit and the moving object inverter circuit in parallel with the converter circuit, the robot inverter circuit, and the moving object inverter circuit.

11. 2. The braking system of claim 1, The moving device is a conveying device that conveys a workpiece.

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