Control device and robot system

Abstract

To provide a control device and a robot system capable of effectively utilizing regenerative power, quickly stopping the operation of the control device, and being miniaturized.SOLUTION: A control device that controls driving of a motor included in a robot, the control device supplying, in an ON state in which a power detecting section detects supply of electric power from an AC power supply, electric power discharged from a regenerative capacitor, stepped down by a step-down circuit section, and output to an energization control circuit section and supplying, in an OFF state in which the power detecting section detects stop of the supply of the electric power from the AC power supply, the electric power discharged from the regenerative capacitor, stepped down by the step-down circuit section, and output to a first discharge resistance section.SELECTED DRAWING: Figure 3

Description

[Technical Field]

[0001] The present invention relates to a control device and a robot system. [Background technology]

[0002] In recent years, due to rising labor costs and labor shortages in factories, robots with robotic arms have begun to perform manufacturing, processing, assembly, and other tasks, accelerating the automation of tasks that were previously performed manually. Robots are also required to operate with low power consumption.

[0003] For example, the robot control device described in Patent Document 1 has a regenerative capacitor that stores regenerative power generated by a motor that drives a robot arm. The regenerative power is stored in the regenerative capacitor and used as power to drive, for example, a control circuit. [Prior art documents] [Patent documents]

[0004] [Patent Document 1] Japanese Patent Application Publication No. 2023-150857 Summary of the Invention [Problem to be solved by the invention]

[0005] However, in the control device described in Patent Document 1, when the power supply of the control device is turned off, the regenerative power remaining in the regenerative capacitor must be consumed by each processor, etc. For this reason, it may take some time for the operation of each processor, etc. to actually stop after the power supply of the control device is turned off. In other words, it may not be possible to quickly stop (shut down) the operation of the control device. [Means for solving the problem]

[0006] The control device of the present invention is a control device that controls the driving of a motor provided in a robot, a power detection unit that detects the supply of power from an AC power source to the control device; a first converter circuit unit that converts AC current supplied from the AC power supply into DC current and outputs the DC current; a drive circuit section that converts the DC current output from the first converter circuit section into a drive current for the motor and outputs the drive current, and that receives regenerative power from the motor; a second converter circuit unit connected in parallel to the first converter circuit unit, which converts AC current supplied from the AC power supply into DC current and outputs the DC current; a step-down circuit unit that steps down the DC current output from the second converter circuit unit and outputs the stepped-down DC current; a current control circuit section that operates by the DC current output from the step-down circuit section and controls the drive circuit section; a regenerative capacitor that stores the regenerative power; a first discharge resistor unit that consumes the power discharged from the regenerative capacitor and stepped down by the step-down circuit unit and output; In an ON state in which the power detection unit detects the supply of power from the AC power supply, the power released from the regenerative capacitor, stepped down by the step-down circuit unit, and output is supplied to the energization control circuit unit, In an OFF state in which the power detection unit detects a stop of power supply from the AC power supply, the control device supplies the power released from the regenerative capacitor, stepped down by the step-down circuit unit, and output to the first discharge resistor unit.

[0007] The robot system of the present invention includes: a robot equipped with a motor; a control device that controls the driving of the motor, The control device a power detection unit that detects the supply of power from an AC power source to the control device; a first converter circuit unit that converts AC current supplied from the AC power supply into DC current and outputs the DC current; a drive circuit section that converts the DC current output from the first converter circuit section into a drive current for the motor and outputs the drive current, and that receives regenerative power from the motor; a second converter circuit unit connected in parallel to the first converter circuit unit, which converts AC current supplied from the AC power supply into DC current and outputs the DC current; a step-down circuit unit that steps down the DC current output from the second converter circuit unit and outputs the stepped-down DC current; a current control circuit section that operates by the DC current output from the step-down circuit section and controls the drive circuit section; a regenerative capacitor that stores the regenerative power; a first discharge resistor unit that consumes the power discharged from the regenerative capacitor and stepped down by the step-down circuit unit and output; In an ON state in which the power detection unit detects the supply of power from the AC power supply, the power released from the regenerative capacitor, stepped down by the step-down circuit unit, and output is supplied to the energization control circuit unit, In an OFF state in which the power detection unit detects a stop in the supply of power from the AC power supply, the power released from the regenerative capacitor, stepped down by the step-down circuit unit, and output is supplied to the first discharge resistor unit. [Brief explanation of the drawings]

[0008] [Figure 1] FIG. 1 is a diagram showing the overall configuration of a robot system equipped with a control device of the present invention. [Figure 2] FIG. 2 is a block diagram of the robot system shown in FIG. [Figure 3] FIG. 3 is a circuit diagram of the control device shown in FIG. [Figure 4] FIG. 4 is a circuit diagram of the comparator shown in FIG. [Figure 5] FIG. 5 is a circuit diagram of the first discharge resistor section shown in FIG. [Figure 6] FIG. 6 is a timing chart for explaining the operations of a conventional control device and the control device shown in FIG. 3 after the supply of power from the AC power supply is stopped. [Figure 7] FIG. 7 is a timing chart for explaining the voltage value of the power supplied from the AC power supply and the timing for detecting the supply of power from the AC power supply. DETAILED DESCRIPTION OF THE INVENTION

[0009] DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS A control device and a robot system according to the present invention will be described in detail below based on the embodiments shown in the accompanying drawings.

[0010] <Embodiment> FIG. 1 is a diagram showing the overall configuration of a robot system equipped with a control device of the present invention. FIG. 2 is a block diagram of the robot system shown in FIG. 1. FIG. 3 is a circuit diagram of the control device shown in FIG. 1. FIG. 4 is a circuit diagram of the comparator shown in FIG. 3. FIG. 5 is a circuit diagram of the first discharge resistor unit shown in FIG. 3. FIG. 6 is a timing chart for explaining the operation after the supply of power from an AC power supply is stopped in a conventional control device and the control device shown in FIG. 3. FIG. 7 is a timing chart for explaining the voltage value of power supplied from the AC power supply and the timing for detecting the supply of power from the AC power supply.

[0011] For ease of explanation, the robot arm 10 will be referred to below as having a base 11 side in FIG. 1 as the "base end" and an opposite side, i.e., an end effector 20 side as the "tip end."

[0012] In this specification, "vertical" means not only when the object is vertical but also when it is slightly tilted from the vertical, for example, within ±10°. In this specification, "parallel" means not only when two objects are parallel but also when they are slightly tilted from the parallel, for example, within ±10°.

[0013] As shown in FIG. 1, a robot system 100 of the present invention includes a robot 1, a control device 3 that controls the robot 1, and a teaching device 4.

[0014] First, the robot 1 will be described. In this embodiment, the robot 1 shown in FIG. 1 is a single-arm, six-axis vertical articulated robot, and includes a base 11 and a robot arm 10. An end effector 20 can be attached to the tip of the robot arm 10. The end effector 20 may be a component of the robot 1, or may be a separate member from the robot 1, i.e., it does not have to be a component of the robot 1.

[0015] The robot 1 is not limited to the configuration shown in the figure, and may be, for example, a double-arm articulated robot or a horizontal articulated robot.

[0016] The base 11 is a support that drivably supports the robot arm 10 at its base end, and is fixed to, for example, the floor of a factory. The base 11 of the robot 1 is electrically connected to the control device 3 via a relay cable. Note that the connection between the robot 1 and the control device 3 is not limited to a wired connection as shown in FIG. 1, and may be, for example, a wireless connection. The robot 1 and the control device 3 may also be connected via a network such as the Internet.

[0017] In this embodiment, the robot arm 10 has a first arm 12, a second arm 13, a third arm 14, a fourth arm 15, a fifth arm 16, and a sixth arm 17, which are connected in this order from the base 11 side. The number of arms that the robot arm 10 has is not limited to six, and may be, for example, one, two, three, four, five, or seven or more. The size of each arm, such as its overall length, is not particularly limited and can be set as appropriate.

[0018] The base 11 and the first arm 12 are connected via a joint 171. The first arm 12 is rotatable around a first rotation axis that extends parallel to the vertical direction relative to the base 11. The first rotation axis coincides with the normal to the floor surface to which the base 11 is fixed.

[0019] The first arm 12 and the second arm 13 are connected via a joint 172. The second arm 13 is rotatable about a second rotation axis extending horizontally relative to the first arm 12. The second rotation axis is parallel to an axis perpendicular to the first rotation axis.

[0020] The second arm 13 and the third arm 14 are connected via a joint 173. The third arm 14 is rotatable relative to the second arm 13 about a third rotation axis extending horizontally. The third rotation axis is parallel to the second rotation axis.

[0021] The third arm 14 and the fourth arm 15 are connected via a joint 174. The fourth arm 15 is rotatable relative to the third arm 14 around a fourth rotation axis that is parallel to the central axis of the third arm 14. The fourth rotation axis is perpendicular to the third rotation axis.

[0022] The fourth arm 15 and the fifth arm 16 are connected via a joint 175. The fifth arm 16 is rotatable about a fifth rotation axis relative to the fourth arm 15. The fifth rotation axis is perpendicular to the fourth rotation axis.

[0023] The fifth arm 16 and the sixth arm 17 are connected via a joint 176. The sixth arm 17 is rotatable about a sixth rotation axis relative to the fifth arm 16. The sixth rotation axis is perpendicular to the fifth rotation axis.

[0024] The sixth arm 17 is the arm located at the most distal end of the robot arm 10. The sixth arm 17 can be displaced together with the end effector 20 by being driven by the robot arm 10.

[0025] 1 has a gripping portion that can grip a workpiece or a tool. When the end effector 20 is attached to the sixth arm 17, the tip of the end effector 20 becomes the tool center point TCP.

[0026] The robot 1 includes motors M1, M2, M3, M4, M5, and M6 as drive units, and encoders E1, E2, E3, E4, E5, and E6. Motor M1 is built into joint 171 and rotates the first arm 12 relative to the base 11 around the first rotation axis. Motor M2 is built into joint 172 and rotates the first arm 12 and the second arm 13 relatively around the second rotation axis. Motor M3 is built into joint 173 and rotates the second arm 13 and the third arm 14 relatively around the third rotation axis. Motor M4 is built into joint 174 and rotates the third arm 14 and the fourth arm 15 relatively around the fourth rotation axis. Motor M5 is built into joint 175 and rotates fourth arm 15 and fifth arm 16 relatively around the fifth rotation axis. Motor M6 is built into joint 176 and rotates fifth arm 16 and sixth arm 17 relatively around the sixth rotation axis. Each of motors M1 to M6 is a three-phase motor driven by three-phase AC.

[0027] Furthermore, encoder E1 is built into joint 171 and detects the position of motor M1. Encoder E2 is built into joint 172 and detects the position of motor M2. Encoder E3 is built into joint 173 and detects the position of motor M3. Encoder E4 is built into joint 174 and detects the position of motor M4. Encoder E5 is built into fifth arm 16 and detects the position of motor M5. Encoder E6 is built into sixth arm 17 and detects the position of motor M6. Note that "detecting position" here refers to detecting the rotation angle of the motor, i.e., the amount of rotation including forward and reverse, and the angular velocity, and the detected information is referred to as "position information."

[0028] 2, motor drivers D1 to D6 are connected to corresponding motors M1 to M6, respectively, and control the driving of the motors. Motor drivers D1 to D6 are built into joint 171, joint 172, joint 173, joint 174, fifth arm 16, and sixth arm 17, respectively.

[0029] Encoders E1 to E6, motors M1 to M6, and motor drivers D1 to D6 are each electrically connected to the control device 3. Position information of motors M1 to M6 detected by encoders E1 to E6, i.e., the amount of rotation, etc., is transmitted to the control device 3 as an electrical signal. Based on this position information, an energization control circuit unit 74 in a power control circuit 10A of the control device 3 shown in FIG. 3 outputs control signals to motor drivers D1 to D6, controlling the energization of motors M1 to M6 to drive motors M1 to M6. In other words, controlling the robot arm 10 means controlling the driving of motors M1 to M6 to control the driving of first arm 12 to sixth arm 17 of the robot arm 10.

[0030] An end effector 20 can be detachably attached to the tip of the robot arm 10. In this embodiment, the end effector 20 is configured as a hand having a pair of claws that can move toward and away from each other and that grip and release a workpiece or tool with each claw. The end effector 20 is not limited to the configuration shown in the figure and may be configured, for example, to have an adsorption portion that grips a workpiece or tool by adsorption with the adsorption portion. The end effector 20 may also be, for example, a polishing machine, grinding machine, cutting machine, spray gun, laser light irradiator, screwdriver, wrench, or other tool.

[0031] Next, the control device 3 and the teaching device 4 will be described. As shown in Figures 1, 2, and 3, in this embodiment, the control device 3 is installed at a location separate from the robot 1. However, this configuration is not limiting, and the control device 3 may be built into the base 11. The control device 3 also has the function of controlling the driving of the robot 1, and is electrically connected to the motors M1 to M6, AC power supply 61, and other parts of the robot. In other words, the control device 3 is a device that controls the driving of motors M1 to M6 provided in the robot 1.

[0032] The control device 3 has a power control circuit 10A including a control unit 31, a storage unit 32, and a communication unit 33. These units are connected to each other so as to be able to communicate with each other via, for example, a bus.

[0033] The control unit 31 includes an energization control circuit unit 74 and the like, and is configured by, for example, a CPU (Central Processing Unit), and reads and executes various programs such as operation programs stored in the storage unit 32. Signals generated by the control unit 31 are transmitted to each unit of the robot 1 via the communication unit 33, and signals from each unit of the robot 1 are received by the control unit 31 via the communication unit 33. This allows the robot arm 10 to perform a predetermined task under predetermined conditions.

[0034] The storage unit 32 stores various programs and the like executed by the control unit 31. Examples of the storage unit 32 include a configuration including a volatile memory such as a RAM (Random Access Memory), a non-volatile memory such as a ROM (Read Only Memory), and a removable external storage device.

[0035] The communication unit 33 transmits and receives signals to and from the control device 3 using an external interface such as a wired LAN (Local Area Network) or a wireless LAN. In this case, communication may be performed via a server (not shown), or via a network such as the Internet.

[0036] As shown in FIGS. 1 and 2, the teaching device 4 is a command device for teaching and has a display 40, which is a display unit. This display 40 is also an operation unit that teaches an operation program to the robot arm 10. In other words, it has the function of creating and inputting an operation program. The display 40 is configured with a touch panel, and various operations and information related to teaching are input by an operator operating it with a finger or a touch pen. The display 40 is configured with, for example, a liquid crystal display (LCD), an organic electroluminescence display (OLED), or the like, and can display various screens in color or monochrome. The touch panel type of the display 40 may be either a pressure-sensitive type or a capacitance type.

[0037] The teaching device 4 includes a control unit 41, a storage unit 42, and a communication unit 43. The control unit 41 is composed of at least one processor such as a CPU (Central Processing Unit), and reads and executes various programs, such as teaching programs, stored in the storage unit 42. The control unit 41 also has a function of controlling the operation of the display 40. Specifically, the control unit 41 displays a rectangular operation screen on the display 40, and generates an operation program for the robot 1 based on information input from the operation screen by touching a desired position, etc. The operation program generated by the control unit 41 is stored in the storage unit 42 and transmitted to the control device 3 via the communication unit 43. This makes it possible to specify a program via the control device 3 that causes the robot arm 10 to perform a predetermined task under predetermined conditions.

[0038] The storage unit 42 stores various programs and the like that can be executed by the control unit 41. Examples of the storage unit 42 include a configuration that includes a volatile memory such as a RAM (Random Access Memory), a non-volatile memory such as a ROM (Read Only Memory), a removable external storage device, etc. The storage unit 42 also stores operation programs created by the control unit 41.

[0039] The communication unit 43 transmits and receives signals to and from the control device 3 using an external interface such as a wired LAN (Local Area Network) or a wireless LAN. In this case, communication may be performed via a server (not shown), or via a network such as the Internet. The communication unit 43 transmits information related to the operating program stored in the storage unit 42 to the control device 3. The communication unit 43 can also receive information stored in the storage unit 32 and store it in the storage unit 42.

[0040] Next, the control device 3 of the robot system 100 will be described in detail with reference to FIG. 3. The control device 3 has a power control circuit 10A including a control unit 31. The power control circuit 10A has an input terminal 62A, a noise removal capacitor 60A, an inrush current prevention resistor 60B, a first converter circuit 62, a regenerative capacitor 63 electrically connected to the output side of the first converter circuit 62, a drive circuit 64, an input / output terminal 62B, a second discharge resistor 65, a potential detection unit 66, a switch 67, a comparator 68, a second converter circuit 71, a power factor correction circuit 72, a first step-down circuit 73, an energization control circuit 74, a second step-down circuit 75, a regenerative power supply unit 76, a power detection unit 77, a first discharge resistor 78, a determination circuit 79, a third step-down circuit 80, and a smoothing circuit 81. The term "connected" includes not only direct connection between terminals but also connection between terminals via a power line or the like.

[0041] The AC power supply 61 is, for example, a 200V AC power supply. The power output by the AC power supply 61, i.e., electrical energy, is input to the first converter circuit unit 62 via an input terminal 62A, a noise reduction capacitor 60A, and an inrush current prevention resistor unit 60B. The input terminal 62A is a terminal to which power is supplied from the AC power supply 61 and to which AC current is input. As shown in FIG. 3 , the two input terminals 62A are each connected to a first converter circuit unit 62 (described later) by an electric wire. The electric wire connecting the lower input terminal 62A to the first converter circuit unit 62 is a low-potential electric wire, and the electric wire connecting the upper input terminal 62A to the first converter circuit unit 62 is a high-potential electric wire that has a higher potential than the low-potential electric wire. The two input terminals 62A are also connected to a second converter circuit unit 71 (described later) by an electric wire. The wire connecting the lower input terminal 62A to the second converter circuit unit 71 is a low-potential wire, and the wire connecting the upper input terminal 62A to the second converter circuit unit 71 is a high-potential wire that has a higher potential than the low-potential wire. In this embodiment, the low-potential wires are each connected to a ground.

[0042] The noise reduction capacitor 60A consists of two capacitors connected in series with a ground connected between them. By passing through the noise reduction capacitor 60A, noise in the power output by the AC power supply 61 is removed, enabling a stable power supply.

[0043] The inrush prevention resistor unit 60B is provided on the high-potential electric wire and includes a resistor and a switch that bypasses the resistor, preventing the flow of inrush current. When the control device 3 is started, etc., an excessive current known as an inrush current is generated due to the storage of electricity in the regenerative capacitor 63, etc. Therefore, when the control device 3 is started, etc., the switch is turned OFF, and the current flows through the resistor, consuming power and preventing the inrush current from flowing to the first converter circuit unit 62, etc. This improves safety. On the other hand, after the control device 3 is started, power is stored in the regenerative capacitor 63, etc., and no inrush current is generated, so the switch is turned ON, preventing current from flowing through the resistor, thereby suppressing power consumption by the resistor.

[0044] The first converter circuit 62 is a bridge rectifier circuit using diodes, and converts AC current input from the AC power supply 61 via a noise removal capacitor 60A and an inrush current prevention resistor 60B into DC current and outputs it.

[0045] A regenerative capacitor 63 is connected on the output side of the first converter circuit unit 62, between the high-potential wiring and the low-potential wiring. The regenerative capacitor 63 is connected in parallel with the drive circuit unit 64 and stores the regenerative power generated by the motors M1 to M6. The regenerative capacitor 63 also functions as a smoothing capacitor that temporarily stores the voltage of the power output from the first converter circuit unit 62 and outputs (discharges) it when it exceeds a predetermined value. In this way, the regenerative capacitor 63 stores and outputs (discharges) not only the regenerative power but also the power output from the AC power source 61 and converted to DC by the first converter circuit unit 62. However, hereinafter, the power output (discharge) by the regenerative capacitor 63 will be described as regenerative power.

[0046] The drive circuit unit 64 also includes motor drivers D1 to D6. Each of the motor drivers D1 to D6 includes an inverter circuit including six switching elements. Each of the motor drivers D1 to D6 performs PWM control, converts the DC current output from the first converter circuit unit 62 into an AC current, which is an example of a drive current, and in this embodiment, converts the AC current into a three-phase AC current. The converted AC current is then selectively supplied to the corresponding motors M1 to M6 via the input / output terminals 62B. The motors M1 to M6 also generate regenerative power, which will be described later, and this regenerative power is input to the motor drivers D1 to D6 via the input / output terminals 62B. The magnitude and timing of the power output from the drive circuit unit 64 to each of the motors M1 to M6 are set by the energization control circuit unit 74.

[0047] 3, the two terminals of the drive circuit unit 64 are each connected to the first converter circuit unit 62 by an electric wire. The electric wire connecting the lower terminal of the drive circuit unit 64 to the first converter circuit unit 62 is a low-potential electric wire, and the electric wire connecting the upper terminal of the drive circuit unit 64 to the first converter circuit unit 62 is a high-potential electric wire that has a higher potential than the low-potential electric wire. In this embodiment, the low-potential electric wire is connected to a ground.

[0048] Furthermore, the terminals through which the drive circuit unit 64 outputs to the motors M1 to M6 are each an input / output terminal 62B. Power is input and output between the motor drivers D1 to D6 and the motors M1 to M6 via the input / output terminals 62B. As each of the motors M1 to M6 is a three-phase motor, three input / output terminals 62B are provided for each motor.

[0049] By driving motors M1 to M6, the robot arm 10 is driven and displaced, but if an attempt is made to suddenly slow down or stop the displacement of the robot arm 10 by cutting off the power supply to motors M1 to M6, the robot arm 10 will not stop instantly in the middle of its displacement due to its inertia, and a back electromotive force, i.e., regenerative power, will be generated in motors M1 to M6.

[0050] Motors M1 to M6 each independently generate regenerative power. The "regenerative power" described below refers to the total power of the regenerative power generated by motors M1 to M6.

[0051] The second discharge resistor 65 is connected in parallel to the drive circuit 64, and when power supply to the motors M1 to M6 is stopped to decelerate them, that is, when regeneration of the motors M1 to M6 is performed, the second discharge resistor 65 converts the regenerative power generated by the motors M1 to M6 into heat and consumes it. Regeneration means operating the drive source such as the motors M1 to M6 so that it generates counter electromotive force when the drive source suddenly decelerates, that is, operating the drive source as a generator.

[0052] When driving motors M1 to M6, the current control circuit 74 operates using power from the AC power supply 61 to control the drive circuit 64, supplying AC, particularly three-phase AC, to motors M1 to M6 at a predetermined timing, frequency, and voltage. When stopping the driving of motors M1 to M6, the current control circuit 74 controls the drive circuit 64 to stop the supply of current to motors M1 to M6. At this time, as described above, back electromotive force is generated in motors M1 to M6, and this power, i.e., regenerative power, is stored in the regenerative capacitor 63. When the amount of charge stored in the regenerative capacitor 63, i.e., the amount of stored power, exceeds the maximum storable value—in this embodiment, when the voltage value of the power input to terminal 69 of comparator 68, described later, exceeds a threshold—the remaining power flows to and is consumed by the second discharge resistor 65, which generates and dissipates heat.

[0053] Hereinafter, the conversion of power into heat in the second discharge resistance section 65 and the dissipation of heat will be simply referred to as "the second discharge resistance section 65 consuming power." This also applies to the first discharge resistance section 78, which will be described later.

[0054] In addition, a switch 67 is connected in series to the second discharge resistor section 65. When the switch 67 is ON, power is supplied to the second discharge resistor section 65, and when the switch 67 is OFF, power is not supplied to the second discharge resistor section 65.

[0055] The potential detection unit 66 detects the potential of the regenerative capacitor 63. A signal corresponding to the detection value detected by the potential detection unit 66 is input to a terminal 69 of a comparator 68.

[0056] It is assumed that the voltage value of the regenerative power and the potential of the regenerative capacitor 63 detected by the potential detection unit 66 are the same value.

[0057] Comparator 68 generates a signal to turn switch 67 ON when the voltage value of the regenerated power from motors M1 to M6 exceeds a threshold value. That is, comparator 68 compares the detection result of potential detection unit 66, i.e., the voltage value of the regenerated power, with a set threshold value, and outputs a signal according to the comparison result to switch 67. When the voltage value of the regenerated power is greater than the threshold value, comparator 68 outputs a signal to switch 67 to turn switch 67 ON. On the other hand, when the voltage value of the regenerated power is equal to or less than the threshold value, comparator 68 outputs a signal to switch 67 to turn switch 67 OFF.

[0058] As shown in Figure 4, the comparator 68 has a comparator main body 681 that performs comparison and outputs a signal according to the comparison result, a terminal 69 that connects to the potential detection unit 66, a terminal 70 that connects to the second step-down circuit unit 75 described below, a threshold terminal 90 to which power having a voltage value corresponding to the threshold value is input, a resistor R1 that is arranged on the wire connecting the comparator main body 681 and terminal 70, a resistor R2 that is arranged on the wire connecting between the comparator main body 681 and resistor R1 and the wire on the output side of the comparator main body 681 and obtains hysteresis by bypassing the comparator main body 681, a resistor R3 that is arranged on the threshold terminal 90 side of resistor R1, and a resistor R4 that is arranged on the wire connecting between resistors R1 and R3 and ground.

[0059] The above-described portion of power control circuit 10A, excluding comparator 68, is the "high-power side" circuit to which a relatively high voltage is applied. Next, the "low-power side" circuit of power control circuit 10A to which a lower voltage than the "high-power side" is applied will be described.

[0060] The second converter circuit unit 71 is connected in parallel with the first converter circuit unit 62, and converts AC current input from the AC power supply 61 via the input terminal 62A and the noise removal capacitor 60A into DC current and outputs it to the power factor correction circuit unit 72. The second converter circuit unit 71 is a bridge rectifier circuit using diodes.

[0061] The power factor correction circuit unit 72 is a circuit for bringing the power factor of the AC power supply 61 closer to 1. The power factor correction circuit unit 72 also has the function of suppressing the high-frequency AC current generated in the AC power supply 61 to a predetermined value or less to protect the CPU, which will be described later, and the like. The power factor correction circuit unit 72 has an output voltage setting resistor 721 that adjusts the output voltage. By appropriately setting the resistance value of the output voltage setting resistor 721, it is possible to set the voltage output from the power factor correction circuit unit 72 to the first step-down circuit unit 73, i.e., the voltage value of the current input to the first step-down circuit unit 73.

[0062] As described above, the control device 3 includes a power factor correction circuit unit 72 that corrects the power factor of the power supplied from the second converter circuit unit 71 and outputs the power to the first step-down circuit unit 73. This improves the power factor, making it possible to effectively utilize the power from the AC power supply 61, and also makes it easy to set the voltage of the current output to the first step-down circuit unit 73.

[0063] The first step-down circuit unit 73 is a linear or switching DC / DC converter that steps down the input voltage and outputs it to the energization control circuit unit 74 and the second step-down circuit unit 75. The voltage supplied to the energization control circuit unit 74 and the second step-down circuit unit 75 is stepped down to, for example, about 24 V.

[0064] The energization control circuit 74, the second step-down circuit 75, the first discharge resistor 78, and the third step-down circuit 80 are connected in parallel. The energization control circuit 74 is a circuit that constitutes part of the control unit 31 described above, and is operated by the DC current output from the first step-down circuit 73 to control the drive circuit 64. That is, the energization control circuit 74 generates a drive control signal and outputs it to the drive circuit 64.

[0065] The second step-down circuit section 75 has the same configuration and function as the first step-down circuit section 73 except for the degree of transformation, and further steps down the voltage stepped down by the first step-down circuit section 73 and supplies it to terminal 70 of the comparator 68 as a comparator power supply voltage. This enables the comparator 68 to operate. The comparator power supply voltage supplied to terminal 70 of the comparator 68 is stepped down by the second step-down circuit section 75 to, for example, about 5 V.

[0066] The comparator 68 compares the input value from the terminal 69 with the input value from the threshold terminal 90 and controls the opening and closing of the switch 67 .

[0067] In this embodiment, the power output from the second step-down circuit unit 75 is used as power for operating the comparator 68, but the present invention is not limited to this, and the power output from the second step-down circuit unit 75 may be used as power input to the threshold terminal 90 of the comparator 68, or may be used for both.

[0068] 3, two terminals of the energization control circuit unit 74 and the second step-down circuit unit 75 are each connected to the second converter circuit unit 71 by an electric wire. The electric wires connecting the lower terminals of the energization control circuit unit 74 and the second step-down circuit unit 75 to the second converter circuit unit 71 are low-potential electric wires, and the electric wires connecting the upper terminals of the energization control circuit unit 74 and the second step-down circuit unit 75 to the second converter circuit unit 71 are high-potential electric wires that have a higher potential than the low-potential electric wires. In this embodiment, the low-potential electric wires are connected to a ground.

[0069] The regenerative power supply unit 76 has a regenerative diode 761 that outputs the DC current of the regenerative power generated on the high-power side to the first step-down circuit unit 73. The regenerative power that the regenerative power supply unit 76 supplies to the first step-down circuit unit 73 includes the direct regenerative power generated in the motors M1 to M6 and the regenerative power released, i.e., discharged, by the regenerative capacitor 63, but hereinafter these will be collectively referred to simply as regenerative power.

[0070] In the regenerative power supply unit 76, the input terminal of the regenerative diode 761, i.e., the anode, is connected to the high-potential wire between the output terminal of the first converter circuit unit 62 and the second discharge resistor unit 65, and the output terminal of the regenerative diode 761, i.e., the cathode, is connected to the input terminal of the high-potential wire of the first step-down circuit unit 73. The regenerative diode 761 allows the passage of regenerative power in only one direction, that is, in the direction from the motors M1 to M6 toward the first step-down circuit unit 73 as shown by arrow A in FIG. 3, but prevents the passage of current in the reverse direction. In other words, the regenerative power supply unit 76 supplies regenerative power from the high-voltage side to the low-voltage side. The regenerative power supplied by the regenerative power supply unit 76 is input to the first step-down circuit unit 73.

[0071] The regenerative power supply unit 76 also has an electric wire that connects the low-potential electric wire of the first converter circuit unit 62 with the low-potential electric wire of the second converter circuit unit 71. This allows the two low-potential electric wires to be easily and accurately set to the same potential. Note that the electric wire connecting the low-potential electric wires may be omitted.

[0072] Although not shown, a switch that switches between enabling and blocking power from the AC power supply 61 to be supplied to the low-voltage side via the regenerative power supply unit 76 or on the AC power supply 61 side of the regenerative power supply unit 76 is provided in the regenerative power supply unit 76. By turning off the switch, power supplied from the AC power supply 61 is prevented from being inadvertently supplied to the low-voltage side via the regenerative power supply unit 76.

[0073] In this way, in the control device 3, the regenerative power supply unit 76 supplies regenerative power from the high-voltage side to the low-voltage side, and after stepping down the voltage, it can be used as power to drive the energization control circuit unit 74, or as power to operate the comparator 68 via the second step-down circuit unit 75, or as power to operate other processors (not shown). Therefore, while the robot 1 is in operation, that is, while the energization control circuit unit 74 and the second step-down circuit unit 75 need to be operated, the regenerative power can be reused and used effectively.

[0074] Here, we will explain the case where, for example, the power supply of the control device 3 is turned off by operating a power switch (not shown) of the control device 3, i.e., the supply of power from the AC power supply 61 to the control device 3 is stopped. When the supply of power from the AC power supply 61 is stopped ("POWER OFF" in FIG. 6), the control unit 31 performs a termination process such as shutting down the system. This termination process includes, for example, recording the progress of an ongoing program and recording various logs. When performing this termination process, the processor of the control unit 31 requires power. This power can be provided by the regenerative power supplied by the regenerative power supply unit 76 described above. Since it is preferable to discharge and consume almost all of the regenerative power stored in the regenerative capacitor 63, which is the supply source, it is necessary to perform a discharge process to consume the regenerative power by operating the processor within the control unit 31 even after the termination process is completed.

[0075] In the past, this discharge process took time (see the upper time chart in FIG. 6 ), resulting in a problem that it took a long time from when the power was turned off until the control device actually shut down, i.e., until the “discharge process is completed” in FIG. 6 . In other words, there was a problem that the control device could not be shut down quickly. In particular, when the regenerative power supply unit 76 is provided, the regenerative power supply unit 76 continues to actively supply power to the first step-down voltage circuit unit 73 until the regenerative power stored in the regenerative capacitor 63 is depleted. Therefore, the first step-down voltage circuit unit 73 continues to step down the voltage of the regenerative power received from the regenerative power supply unit 76 and output it to the energization control circuit unit 74 and the second step-down voltage circuit unit 75 until the regenerative power stored in the regenerative capacitor 63 is depleted. Therefore, the energization control circuit unit 74, the second step-down voltage circuit unit 75, etc. continue to operate until the power supply from the first step-down voltage circuit unit 73 is depleted, resulting in a problem that it took a long time to shut down the control device 3. In contrast to this, the control device 3 of this embodiment can solve the above problem by adopting the following configuration.

[0076] 3 detects the supply of power from the AC power supply 61 to the control device 3. In this embodiment, the power detection unit 77 is configured with a detection circuit that detects the voltage of the power output from the AC power supply 61 and input to the control device 3, that is, the voltage between the high-potential electric wire connecting the upper input terminal 62A to the first converter circuit unit 62 and the low-potential electric wire connecting the lower input terminal 62A to the first converter circuit unit 62.

[0077] The object of detection by the power detection unit 77 is not limited to voltage, but may be, for example, current, power, etc., as long as it can detect the supply of power from the AC power supply 61 to the control device 3.

[0078] Although not shown, the power detection unit 77 is electrically connected to the determination circuit unit 79. Information related to the power detected by the power detection unit 77, in this embodiment, information related to the voltage, i.e., information on the detected voltage value, is converted into an electric signal and input to the determination circuit unit 79.

[0079] The determination circuit unit 79 determines whether or not power is being supplied from the AC power supply 61 to the control device 3 based on the detection value of the power detection unit 77. For example, the determination circuit unit 79 compares the detection value of the power detection unit 77 with a preset threshold value. If the detection value is greater than the threshold value, the determination circuit unit 79 determines that power is being supplied from the AC power supply 61 to the control device 3. If the detection value is equal to or less than the threshold value, the determination circuit unit 79 determines that power is not being supplied from the AC power supply 61 to the control device 3. When the determination circuit unit 79 determines that power is being supplied from the AC power supply 61 to the control device 3, this state is referred to as the "ON state." When the determination circuit unit 79 determines that power is not being supplied from the AC power supply 61 to the control device 3, this state is referred to as the "OFF state." When the determination circuit unit 79 determines that power is not being supplied from the AC power supply 61 to the control device 3, this state is referred to as the "OFF state." When the determination circuit unit 79 determines that power is not being supplied from the AC power supply 61 to the control device 3, i.e., the OFF state, the determination circuit unit 79 outputs a signal to activate the first discharge resistor unit 78.

[0080] The configuration of the determination circuit unit 79 is not limited to the above configuration. The determination circuit unit 79 may also be configured to include, for example, a comparator. In this case, the determination circuit unit 79 uses the comparator to compare the detection value of the power detection unit 77 with a preset threshold value, and based on the result, outputs a signal to activate the first discharge resistor unit 78 if there is no power supply from the AC power supply 61 to the control device 3.

[0081] As shown in Fig. 7, the voltage value of the power supplied from the AC power supply 61 repeatedly increases and decreases in a predetermined cycle. Furthermore, the voltage detection unit 77 detects the voltage intermittently, that is, at predetermined time intervals. In this embodiment, the voltage detection is performed at the peak of the AC voltage of the AC power supply 61 in each cycle, and the determination circuit unit 79 determines whether or not power is being supplied from the AC power supply 61 to the control device 3 based on the detection value of the power detection unit 77. This allows the determination circuit unit 79 to accurately determine whether or not power is being supplied from the AC power supply 61 to the control device 3.

[0082] The voltage detection is not limited to the above timing, and may be performed, for example, every multiple of one cycle of the AC voltage of the AC power supply 61. Furthermore, the voltage detection may be performed every half cycle of the AC voltage of the AC power supply 61, every 1.5 times one cycle of the AC voltage of the AC power supply 61, or every cycle obtained by adding half a cycle to a multiple of one cycle of the AC voltage of the AC power supply 61. The voltage detection may be performed at a point shifted from the peak of the AC voltage of the AC power supply 61.

[0083] In this way, the power detection unit 77 detects the voltage at predetermined time intervals, and the determination circuit unit 79 determines at predetermined time intervals whether power is being supplied from the AC power supply 61 to the control device 3. That is, the determination circuit unit 79 determines whether the control device 3 is in the ON state or the OFF state at predetermined time intervals. This makes it possible to accurately determine whether the control device 3 is in the ON state or the OFF state while reducing unnecessary operations compared to when the control device 3 is continuously detected and determined, and to start the discharge process (described later) quickly and at the correct timing.

[0084] When the determination circuit section 79 determines that the first discharge resistor section 78 is in the ON state, it outputs a signal to the first discharge resistor section 78 to turn OFF a switching element 782 of the first discharge resistor section 78, which will be described later. Specifically, the determination circuit section 79 does not output a signal to the first discharge resistor section 78. On the other hand, when the determination circuit section 79 determines that the first discharge resistor section 78 is in the OFF state, it outputs a signal to the first discharge resistor section 78 to turn ON the switching element 782 of the first discharge resistor section 78.

[0085] 3 and 5, the first discharge resistor unit 78 is provided on the low-voltage side and consumes the power released from the regenerative capacitor 63 and stepped down and output by the first step-down circuit unit 73. The first discharge resistor unit 78 has a resistor 781 and a switching element 782 that switches between supplying or cutting off the power stepped down and output by the first step-down circuit unit 73 to the resistor 781.

[0086] The resistor 781 generates heat when energized and discharges the regenerative capacitor 63, and two resistors are provided in the illustrated configuration. Each resistor 781 is connected in series. Each resistor 781 is also connected in series with the first step-down circuit unit 73.

[0087] The switching elements 782 are connected in series with the resistors 781, and can be switched ON / OFF in response to a signal output from the determination circuit unit 79. When the switching elements 782 are ON, the power stepped down and output by the first step-down circuit unit 73 can be supplied to the resistors 781. On the other hand, when the switching elements 782 are OFF, the power stepped down and output by the first step-down circuit unit 73 can be supplied to the energization control circuit unit 74, the second step-down circuit unit 75, and the third step-down circuit unit 80.

[0088] Conventionally, because there was no part equivalent to the first discharge resistor 78, it took a long time from the completion of the termination process until the completion of the discharge process, as shown in the upper time chart of FIG. 6. In the present invention, the first discharge resistor 78 is provided on the low-voltage side, and the discharge process can be performed by the first discharge resistor 78 in the OFF state. This makes it possible to shorten the time until the discharge process is completed, as shown in the lower time chart of FIG. 6. As a result, the operation of the control device 3 can be stopped (shut down) quickly.

[0089] Furthermore, since the first discharge resistor unit 78 consumes the power stepped down and output by the first step-down circuit unit 73, sufficient heat dissipation can be achieved even if small resistors are used as the resistors 781 of the first discharge resistor unit 78. This allows the first step-down circuit unit 73 to be made smaller, and therefore the control device 3 to be made smaller.

[0090] As described above, the control device 3 having the first discharge resistor 78 can quickly stop the operation of the control device 3 (shutdown), and furthermore, the control device 3 can be made smaller in size.

[0091] Furthermore, according to the control device 3 having the first discharge resistor unit 78 and the regenerative power supply unit 76, the operation of the control device 3 can be quickly stopped (shut down) while the robot 1 is being driven, while the regenerative power is reused by the regenerative power supply unit 76.

[0092] Here, in the first discharge resistor unit 78, the resistance value of all the resistors used to consume the power after being stepped down by the first step-down circuit unit 73, i.e., the resistance value of the combined resistor, in this embodiment, the resistance value of the combined resistor of the two resistors 781 connected in series, is defined as R78. Also, in the second discharge resistor unit 65, the resistance value of all the resistors used to consume the regenerative power from the drive circuit unit 64, i.e., the resistance value of the combined resistor, is defined as R65.

[0093] The first discharge resistor section 78 consumes the power after being stepped down by the first step-down circuit section 73, so it is preferable that the resistance value R78 of the first discharge resistor section 78 is smaller than the resistance value R65 of the second discharge resistor section 65. This allows the first discharge resistor section 78 to be miniaturized while still allowing the power to be consumed appropriately.

[0094] Furthermore, the ratio R65 / R78 of the resistance value R65 to the resistance value R78 is not particularly limited and is determined appropriately depending on various conditions, but is preferably 4.5 or more and 30 or less, and more preferably 7 or more and 10 or less, thereby making it possible to more reliably exhibit the above-mentioned effects.

[0095] The resistance value R78 is not particularly limited and is determined appropriately depending on various conditions, but is preferably 1 Ω or more and 20 Ω or less, and more preferably 5 Ω or more and 10 Ω or less, which allows the above-mentioned effects to be more reliably achieved.

[0096] The resistance value R65 is not particularly limited and is determined appropriately depending on various conditions, but is preferably 30Ω or more and 90Ω or less, and more preferably 50Ω or more and 70Ω or less, so that the above-mentioned effects can be more reliably exhibited.

[0097] The third step-down circuit section 80 is connected in parallel with the energization control circuit section 74, the second step-down circuit section 75, and the first discharge resistor section 78. The third step-down circuit section 80 has the same configuration and function as the first step-down circuit section 73 and the second step-down circuit section 75, except for the degree of voltage transformation. The third step-down circuit section 80 further steps down the voltage stepped down by the first step-down circuit section 73 and supplies the voltage to the determination circuit section 79 as a power supply voltage for the determination circuit section. This enables the operation of the determination circuit section 79. The power supply voltage for the determination circuit section supplied to the determination circuit section 79 is stepped down by the third step-down circuit section 80 to, for example, about 3.3 V. The determination circuit section 79 operates using the power supply voltage for the determination circuit section stepped down by the third step-down circuit section 80, and can switch the switching element 782 of the first discharge resistor section 78 on and off.

[0098] The smoothing circuit unit 81 smoothes the voltage of the power output from the second converter circuit unit 71. The smoothing circuit unit 81 also smoothes the voltage of the regenerated power. This smoothing circuit unit 81 has a smoothing capacitor 811 connected in parallel with the first step-down circuit unit 73. By outputting the power smoothed by the smoothing capacitor 811 to the first step-down circuit unit 73, the first step-down circuit unit 73 can stably step down the voltage. Therefore, the first discharge resistor unit 78 can stably and efficiently consume the regenerated power that is stepped down and output by the first step-down circuit unit 73. As a result, heat dissipation can be performed more quickly.

[0099] Since the smoothing circuit unit 81 smoothes the voltage of the power after it has been stepped down by the first step-down circuit unit 73, it is preferable that the capacitance C1 of the smoothing capacitor 811 is smaller than the capacitance C2 of the regenerative capacitor 63. This allows the smoothing circuit unit 81 to be made smaller while still effectively performing the smoothing.

[0100] The ratio C1 / C2 of the capacitance C1 to the capacitance C2 is not particularly limited and can be determined appropriately depending on various conditions, but is preferably 0.01 to 0.56, more preferably 0.04 to 0.16, thereby ensuring the above-mentioned effects. The capacitance C1 may be the same as the capacitance C2, or may be larger than the capacitance C2.

[0101] The capacitance C1 is not particularly limited and is determined appropriately depending on various conditions, but is preferably 100 uF or more and 560 uF or less, and more preferably 220 uF or more and 470 uF or less, so that the above-mentioned effects can be more reliably achieved.

[0102] The capacitance C2 is not particularly limited and is determined appropriately depending on various conditions, but is preferably 1000 uF or more and 10000 uF or less, and more preferably 3000 uF or more and 6000 uF or less, which allows the above-mentioned effects to be more reliably achieved.

[0103] As described above, the control device 3 controls the driving of the motors M1 to M6 equipped in the robot 1, and includes a power detection unit 77 that detects the supply of power from the AC power source 61 to the control device 3, a first converter circuit unit 62 that converts the AC current supplied from the AC power source 61 into a DC current and outputs it, a drive circuit unit 64 that converts the DC current output from the first converter circuit unit 62 into an AC current, which is an example of a drive current for the motors M1 to M6, and outputs it, and also receives regenerative power from the motors M1 to M6 as input, a second converter circuit unit 71 that is connected in parallel with the first converter circuit unit 62 and converts the AC current supplied from the AC power source 61 into a DC current and outputs it, and a step-down converter unit 72 that steps down the DC current output from the second converter circuit unit 71 and outputs it. the power supply 61 is supplied to the first discharge resistor 78. In an ON state where a power detection unit 77 detects the supply of power from the AC power supply 61, the power discharged from the regenerative capacitor 63, stepped down by the first step-down circuit unit 73, and output is supplied to the energization control circuit unit 74. In an OFF state where the power detection unit 77 detects the stop of the supply of power from the AC power supply 61, the power discharged from the regenerative capacitor 63, stepped down by the first step-down circuit unit 73, and output is supplied to the first discharge resistor 78. This enables the operation of the control device 3 to be stopped (shut down) quickly, and the control device 3 to be made smaller.

[0104] In this embodiment, the power detection unit 77 detects the voltage upstream of the first converter circuit unit 62, but the present invention is not limited to this and may detect the voltage at another location, for example, the voltage downstream of the first converter circuit unit 62, specifically the voltage between the high-potential wire and the low-potential wire connecting the first converter circuit unit 62 and the drive circuit unit 64.

[0105] Furthermore, although AC current has been used as an example of the drive current for motors M1 to M6, the present invention is not limited to this, and the drive current for motors M1 to M6 may be DC current.

[0106] The robot system 100 also includes a robot 1 equipped with motors M1 to M6, and a control device 3 that controls the driving of the motors M1 to M6. The control device 3 includes a power detection unit 77 that detects the supply of power to the control device 3 from an AC power source 61, a first converter circuit unit 62 that converts AC current supplied from the AC power source 61 into DC current and outputs it, a drive circuit unit 64 that converts the DC current output from the first converter circuit unit 62 into AC current, which is an example of a drive current for the motors M1 to M6, and to which regenerative power from the motors M1 to M6 is input, a second converter circuit unit 71 that is connected in parallel with the first converter circuit unit 62 and converts AC current supplied from the AC power source 61 into DC current and outputs it, a first step-down circuit unit 73 that acts as a step-down circuit unit that steps down the DC current output from the second converter circuit unit 71 and outputs it, and a first step-down circuit unit 74 that acts as a step-down circuit unit that steps down the DC current output from the second converter circuit unit 71 and outputs it. The robot system 100 includes an energization control circuit 74 that operates using the DC current output from the step-down circuit 73 and controls the drive circuit 64, a regenerative capacitor 63 that stores regenerative power, and a first discharge resistor 78 that consumes the power released from the regenerative capacitor 63 and stepped down by the first step-down circuit 73 before being output. In an ON state where the power detection unit 77 detects the supply of power from the AC power source 61, the power released from the regenerative capacitor 63 and stepped down by the first step-down circuit 73 before being output is supplied to the energization control circuit 74. In an OFF state where the power detection unit 77 detects the stop of the supply of power from the AC power source 61, the power released from the regenerative capacitor 63 and stepped down by the first step-down circuit 73 before being output is supplied to the first discharge resistor 78. This allows the operation of the control device 3 to be stopped (shutdown) quickly, and the control device 3 can be made smaller. This allows the robot system 100 to be energy-efficient and more compact overall.

[0107] The robot 1 also has a regenerative power supply unit 76 that outputs regenerative power to a first step-down circuit unit 73 serving as a step-down circuit unit, and in an ON state where a power detection unit 77 detects the supply of power from the AC power supply 61, the power is released from the regenerative capacitor 63 to the regenerative power supply unit 76, stepped down by the first step-down circuit unit 73, and output, and is supplied to the energization control circuit unit 74, and in an OFF state where the power detection unit 77 detects the stop of the supply of power from the AC power supply 61, the power is released from the regenerative capacitor 63 to the regenerative power supply unit 76, stepped down by the first step-down circuit unit 73, and output, and is supplied to a first discharge resistor unit 78. This allows the regenerative power to be used effectively while the robot 1 is being driven, and allows the operation of the control device 3 to be stopped (shut down) quickly.

[0108] The first discharge resistor unit 78 has a resistor 781 and a switching element 782 that switches whether to supply or cut off the power that is stepped down and output by the first step-down circuit unit 73 serving as a step-down circuit unit to the resistor 781. This makes it possible to switch whether or not to consume power in the first discharge resistor unit 78 at a desired timing, that is, depending on whether the supply of power from the AC power supply 61 is turned on or off.

[0109] In this embodiment, the first discharge resistance section 78 has been described as having two resistors 781, but the present invention is not limited to this, and one or three or more resistors 781 may be provided.

[0110] The control device 3 also includes a smoothing circuit 81 that smoothes the voltage output from the second converter circuit 71. This allows the first discharge resistor 78 to consume power stably and efficiently, thereby enabling heat dissipation to be performed more quickly. The smoothing circuit unit 81 may be omitted, or two or more may be provided.

[0111] Furthermore, the power detection unit 77 detects the voltage of the power supplied from the AC power supply 61, and the control device 3 includes a determination circuit unit 79 that determines whether or not power is being supplied from the AC power supply 61 to the control device 3 based on the value detected by the power detection unit 77. This makes it possible to accurately determine whether or not power is being supplied from the AC power supply 61.

[0112] Furthermore, the voltage detection unit 77 detects the voltage at predetermined time intervals. This makes it possible to accurately detect and determine whether or not power is being supplied from the AC power supply 61 to the control device 3, while reducing unnecessary operations, compared to when the supply of power from the AC power supply 61 to the control device 3 is continuously detected and determined.

[0113] The timing of detection by the power detection unit 77 and the timing of judgment by the judgment circuit unit 79 are not limited to the above configuration, and for example, the power detection unit 77 may be configured to detect at all times, and the judgment circuit unit 79 may be configured to make judgments at all times.

[0114] The control device 3 also includes a second discharge resistor 65 that is connected in parallel with the drive circuit 64 and consumes the regenerated power from the drive circuit 64 when the voltage value of the regenerated power exceeds a threshold value. This allows the remaining power to be consumed when, for example, the amount of electricity stored in the regenerative capacitor 63 exceeds the maximum amount that can be stored. The second discharge resistor 65 may be omitted, or two or more may be provided.

[0115] While the control device and robot system of the present invention have been described above based on the illustrated embodiments, the present invention is not limited to these, and the configurations of the components in the control device and robot system can be replaced with any other configurations having similar functions. Furthermore, any other components or functional components may be added to the control device and robot system. [Explanation of symbols]

[0116] 1...robot, 3...control device, 4...teaching device, 10...robot arm, 10A...power control circuit, 11...base, 12...first arm, 13...second arm, 14...third arm, 15...fourth arm, 16...fifth arm, 17...sixth arm, 20...end effector, 31...control unit, 32...storage unit, 33...communication unit, 40...display, 41...control unit, 42...storage unit, 43...communication unit, 60A...noise removal capacitor, 60B...inrush prevention resistor unit, 61... AC power supply, 62...first converter circuit section, 62A...input terminal, 62B...input / output terminal, 63...regenerative capacitor, 64...drive circuit section, 65...second discharge resistor section, 66...potential detection section, 67...switch, 68...comparator, 69...terminal, 70...terminal, 71...second converter circuit section, 72...power factor correction circuit section, 73...first step-down circuit section, 74...energization control circuit section, 75...second step-down circuit section, 76...regenerative power supply section, 77...power detection section, 78...first discharge resistor section , 79...Determination circuit section, 80...Third step-down circuit section, 81...Smoothing circuit section, 90...Threshold value terminal, 100...Robot system, 171...Joint, 172...Joint, 173...Joint, 174...Joint, 175...Joint, 176...Joint, 681...Comparator main body, 721...Output voltage setting resistor, 761...Regenerative diode, 781...Resistor, 782...Switching element, 811...Smoothing capacitor, A...Arrow, D1...Motor driver, D2...Motor driver , D3...motor driver, D4...motor driver, D5...motor driver, D6...motor driver, E1...encoder, E2...encoder, E3...encoder, E4...encoder, E5...encoder, E6...encoder, M1...motor, M2...motor, M3...motor, M4...motor, M5...motor, M6...motor, R1...resistor, R2...resistor, R3...resistor, R4...resistor, TCP...tool center point

Claims

1. A control device that controls the driving of a motor provided in a robot, a power detection unit that detects the supply of power from an AC power source to the control device; a first converter circuit unit that converts AC current supplied from the AC power supply into DC current and outputs the DC current; a drive circuit section that converts the DC current output from the first converter circuit section into a drive current for the motor and outputs the drive current, and that receives regenerative power from the motor; a second converter circuit unit connected in parallel to the first converter circuit unit and configured to convert AC current supplied from the AC power supply into DC current and output the DC current; a step-down circuit unit that steps down the DC current output from the second converter circuit unit and outputs the stepped-down DC current; a current control circuit section that operates by the DC current output from the step-down circuit section and controls the drive circuit section; a regenerative capacitor that stores the regenerative power; a first discharge resistor unit that consumes the power discharged from the regenerative capacitor and stepped down by the step-down circuit unit and output; In an ON state in which the power detection unit detects the supply of power from the AC power supply, the power discharged from the regenerative capacitor, stepped down by the step-down circuit unit, and output is supplied to the energization control circuit unit, a control device that, in an OFF state in which the power detection unit detects a stop of power supply from the AC power source, supplies the power released from the regenerative capacitor, stepped down by the step-down circuit unit, and output to the first discharge resistor unit.

2. a regenerative power supply unit that outputs the regenerative power to the step-down circuit unit, In an ON state in which the power detection unit detects the supply of power from the AC power supply, the power is discharged from the regenerative capacitor to the regenerative power supply unit, and the power is stepped down by the step-down circuit unit and output, and the power is supplied to the energization control circuit unit; 2. The control device according to claim 1, wherein, in an OFF state in which the power detection unit detects a stop of power supply from the AC power supply, the power released from the regenerative capacitor to the regenerative power supply unit, reduced in voltage by the step-down circuit unit, and output is supplied to the first discharge resistor unit.

3. 3. The control device according to claim 1, wherein the first discharge resistor unit includes a resistor and a switching element that switches between supplying and cutting off the power stepped down and output by the step-down circuit unit to the resistor.

4. 3. The control device according to claim 1, further comprising a smoothing circuit section that smoothes the voltage output from the second converter circuit section.

5. the power detection unit detects a voltage of the power supplied from the AC power supply, 3. The control device according to claim 1, further comprising a determination circuit section that determines whether or not power is being supplied from the AC power source to the control device based on a value detected by the power detection section.

6. The control device according to claim 5 , wherein the detection of the voltage by the power detection unit is performed at predetermined time intervals.

7. 3. The control device according to claim 1, further comprising a second discharge resistor connected in parallel with the drive circuit unit and configured to consume the regenerated power from the drive circuit unit when a voltage value of the regenerated power exceeds a threshold value.

8. a robot having a motor; a control device that controls the driving of the motor, The control device a power detection unit that detects the supply of power from an AC power source to the control device; a first converter circuit unit that converts AC current supplied from the AC power supply into DC current and outputs the DC current; a drive circuit section that converts the DC current output from the first converter circuit section into a drive current for the motor and outputs the drive current, and that receives regenerative power from the motor; a second converter circuit unit connected in parallel to the first converter circuit unit and configured to convert AC current supplied from the AC power supply into DC current and output the DC current; a step-down circuit unit that steps down the DC current output from the second converter circuit unit and outputs the stepped-down DC current; a current control circuit section that operates by the DC current output from the step-down circuit section and controls the drive circuit section; a regenerative capacitor that stores the regenerative power; a first discharge resistor unit that consumes the power discharged from the regenerative capacitor and stepped down by the step-down circuit unit and output; In an ON state in which the power detection unit detects the supply of power from the AC power supply, the power discharged from the regenerative capacitor, stepped down by the step-down circuit unit, and output is supplied to the energization control circuit unit, a power detection unit that detects a stop of power supply from the AC power supply and is in an OFF state, wherein the power detection unit detects a stop of power supply from the AC power supply and supplies the power released from the regenerative capacitor, stepped down by the step-down circuit unit, and output to the first discharge resistor unit.

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