JP5308840B2 - Robot system with power supply adjustment device - Google Patents

Description

  The present invention relates to a robot system that includes a power supply adjustment device having a function of adjusting a current amount to a robot control device, and that can perform a cooperative operation between a human and an industrial robot.

  A high-power industrial robot that may harm humans needs to be stopped or speed limited by a control device when a human is present in the robot movement range. In the speed control state, a person such as an operator needs to always hold a state signal switch such as a deadman switch, and both hands are not free. In addition, human beings hold the state signal switch and operate the switch in an emergency to stop the industrial robot.

  As a technique for avoiding a dangerous operation of the robot when the robot becomes uncontrollable, for example, Patent Document 1 discloses a method of generating a plurality of DC output voltages from one AC input voltage using one insulating transformer. There is disclosed a robot controller power supply device including a circuit and an output voltage monitoring circuit that collectively monitors the plurality of DC output voltages and transmits the monitoring result to the robot controller.

Japanese Patent Laid-Open No. 9-298875

  When a human does not hold the state signal switch as described above and performs a simultaneous cooperative operation with the industrial robot in an area where the industrial robot is operating, an emergency state is not detected and human safety is prevented. Not secured. Therefore, it is necessary to control the operating speed and static force of the industrial robot so as not to harm humans, and a control device having a complicated safety structure is required.

  Therefore, the present invention depends on the safety structure of the control device when performing a simultaneous cooperative operation with the industrial robot in a region where the industrial robot is operating in a state where the human is not holding the state signal switch or the like. The purpose is to provide a robot system constructed so as not to harm human beings.

  In order to achieve the above object, an invention according to claim 1 is directed to an industrial robot, a control device that controls the industrial robot, a power supply adjuster that adjusts a current to the control device, and an industrial robot. In a robot system including a human detection device that detects the presence of a human in an operation area, the power supply adjuster includes a communication means for receiving an output signal of the human detection device, and the industrial robot operates at a maximum. A first current mode for supplying a current that can be operated at a speed and capable of maintaining a maximum static force, and an operating speed and a static force of the industrial robot that are lower than the maximum operating speed, respectively. And a second current mode for supplying a current limited to a limited static force lower than the maximum static force, and switching between the first current mode and the second current mode is performed via the control device. Without, characterized in that the feed regulator performed by the output signal from the human detection device, to provide a robot system.

  According to a second aspect of the present invention, in the robot system according to the first aspect, the power supply adjuster outputs an output signal indicating that a human has entered the operation area of the industrial robot to the human detection device. The first current mode is used when not being received from the first detection mode, and the first current mode is used, and when the output signal indicating that a human has entered the operation area of the industrial robot is received from the human detection device, the first current mode is used. A robot system is provided, characterized by using a two-current mode.

  According to a third aspect of the present invention, in the robot system according to the first or second aspect, the industrial robot has a traveling device for moving within a predetermined traveling area, and the traveling device is A robot system is provided that is operable at a maximum traveling speed in one current mode and is limited to a limited traveling speed lower than the maximum traveling speed in the second current mode.

  According to the robot system including the power supply device according to the present invention, when the operator and the robot perform the cooperative operation, the power supply adjuster is used when the control device configuration makes it difficult to prevent the robot from running away. Since the current to the robot can be limited without going through the robot, the output of the robot is limited to the extent that the runaway robot does not harm the worker, and the safety of the worker can be ensured.

  By switching the current mode according to the output signal of the human detection device by the power supply regulator, the current mode can be switched with a simple configuration without providing the control device with a complicated function.

  Moreover, when an industrial robot is provided with a self-propelled device, the traveling speed of the robot can be appropriately limited.

It is a figure showing the schematic structure of one embodiment of the robot system concerning the present invention. It is a figure which shows the example of 1 structure of the robot control apparatus contained in the robot system of FIG. It is a figure similar to FIG. 1, Comprising: It is a figure which shows the case where a human invades in the operation | movement area | region of a robot. It is a figure which shows the example of 1 structure of the electric power feeding adjustment apparatus contained in the robot system of FIG. It is a figure which shows the other structural example of the electric power feeding adjustment apparatus contained in the robot system of FIG. It is a figure which shows the 1st specific example of the electric current value limiting part contained in an electric power feeding adjustment apparatus. It is a figure which shows the 2nd specific example of the electric current value limiting part contained in an electric power feeding adjustment apparatus. It is a figure which shows the 3rd specific example of the electric current value limiting part contained in an electric power feeding adjustment apparatus. It is a figure which shows the 4th specific example of the electric current value limiting part contained in an electric power feeding adjustment apparatus. It is a figure which shows the 5th specific example of the electric current value limiting part contained in an electric power feeding adjustment apparatus. It is a figure which shows schematic structure of embodiment of the robot system which concerns on this invention when an industrial robot is a self-propelled robot.

  FIG. 1 is a diagram showing a construction example of a robot system according to the present invention. The robot system 10 includes an industrial robot (hereinafter abbreviated as a robot) 12, a robot control device (hereinafter abbreviated as a control device) 14 for controlling the robot 12, a power supply 16 for supplying power to the control device 14, and a power supply 16 A power supply adjustment device or a power supply adjuster 18 having a function of adjusting a current from the power supply to the control device 14. The robot system 10 is designed so that a robot 12 and a human 20 such as an operator can perform a cooperative operation. The robot operation area 22 in which the robot 12 is allowed to pass or pass, and the human 20 There is a robot non-operation area 24 in which the presence or passage of the robot 12 is allowed but the presence or passage of the robot 12 is not allowed.

  FIG. 2 is a diagram illustrating a configuration example of the control device 14. The control device 14 includes a CPU 26 that performs various arithmetic processes, an interface 28 that performs input / output between an operator and other external devices, and a memory 30 that temporarily or permanently stores various data. These are connected to each other via an internal bus 32 or the like. Further, the control device 14 receives the output of the power supply adjustment device 18 and creates a current output circuit (servo amplifier) 34 for driving a servo motor (not shown) of the robot 12 and a control command to the servo motor. And an axis control unit 36. Here, the input power supply to the control device 14 may be prepared separately for the control unit and for the amplifier, or a common power source may be prepared for the control unit and the amplifier. The voltage to the control unit can be set to a desired voltage by using an AC / DC circuit or a DC / DC circuit depending on the type of input power supply.

  Although the robot 12 does not enter the robot non-operation area 24 described above, there is a possibility that the human 20 enters the robot operation area 22 as shown in FIG. Therefore, when the human 20 enters the robot motion area 22, for example, when the human 20 has stepped over the boundary line 38 between both motion areas, the human detection device 40 detects this. Specific examples of the human detection device 40 include a light curtain using infrared rays and various safety signal switches such as a safety mat. Information such as the detection result of the human detection device 40 is sent to the power supply adjuster 18 in real time.

  The power supply adjuster 18 is configured to set a first current mode for supplying a current that allows the robot 12 to operate at a maximum operation speed and maintain a maximum static force, and an operation speed and a static force of the robot 12, respectively. And a second current mode for supplying a current limited to a limited operating speed lower than the maximum operating speed and a limited static force lower than the maximum static force, and controlling switching between the first current mode and the second current mode. This can be done by an output signal from the human detection device 40 without going through the device 14. Specifically, the power supply adjuster 18 has a function of changing at least the amount of current to the servo amplifier 34 of the robot control device 14, and immediately after the detection device 40 detects that the human 20 has entered the robot operation region 22. The amount of current to the servo amplifier 34 is adjusted by a changeover switch or the like which will be described later. FIG. 4 a is a diagram illustrating a configuration example of the power supply regulator 18. The power feeding adjuster 18 includes a CPU 42 that performs various arithmetic processes, an interface 44 that performs input / output between the human detection device 40 and the like, and a memory 46 that temporarily or permanently stores various data. These are connected to each other via an internal bus 48 or the like. The human detection device 40 and the power supply adjuster 18 are connected to each other by a wired or wireless communication means 49 schematically illustrated. The power supply adjuster 18 limits the input current from the power supply 18 and sends it to the control device 14 when the human detection device 40 detects that the human 20 has entered the robot operation area 22. 50. A specific example of the current limiting unit 50 will be described later.

  FIG. 4B is a diagram illustrating another configuration example of the power feeding regulator. 4B is different from the power supply regulator 18 shown in FIG. 4A in that an input signal processing unit 52 such as a relay is provided instead of the CPU 42, the interface 44, and the memory 46. The input signal processing unit 52 is configured to convert information from the detection device 40 into a current limiting signal and send it to the current limiting unit 50.

  FIGS. 5a to 5e are diagrams showing preferred specific examples of the current limiting unit 50 of the power supply regulator 18 or 18 ′. The current limiting unit 50a according to the first specific example shown in FIG. 5a includes a breaker 52 that cuts off the circuit when a current of a predetermined value or more flows, a first line 54 that prevents the current from the power source 16 from passing through the breaker 52, It has the 2nd line 56 which makes the electric current from the power supply 16 pass through the breaker 52, and the switch 58 which can switch the 1st line 54 and the 2nd line 56. FIG. In the example of FIG. 5a, the switch 58 is connected to the first line 54 side when the human has not entered the robot operation area, that is, when the current limit signal is not sent to the current limiter 50a (first current mode). ), The current limiting unit 50a does not exhibit a current limiting function. On the other hand, when a human has entered the robot operation area, that is, when the current limit signal S is sent to the current limiter 50a (for example, the switch 58), the switch 58 is connected to the second line 56 side ( Second current mode). If the predetermined value at which the breaker 52 operates is set to a value that limits the output of the robot to such an extent that it does not harm humans even if the robot runs away, Since the current from the power supply 16 does not exceed a predetermined value, human safety within the robot operation area is ensured.

  The current limiter 50b according to the second specific example shown in FIG. 5b includes a first breaker 60 that shuts off the circuit when a current greater than or equal to a first predetermined value flows, and a second predetermined value that is lower than the first predetermined value. A second breaker 62 that cuts off the circuit when a current greater than the value flows, a first line 64 that passes the current from the power source 16 through the first breaker 60, and a second line that passes the current from the power source 16 through the second breaker 62. And a switch 68 capable of switching between the first line 64 and the second line 66. In the example of FIG. 5b, the switch 68 is connected to the first line 64 side when the human has not entered the robot operation area, that is, when the current limit signal is not sent to the current limiter 50b (first current mode). ), The current limiting unit 50b does not exhibit a current limiting function. On the other hand, when a human has entered the robot operation area, that is, when the current limit signal S is sent to the current limiter 50b (for example, the switch 68), the switch 68 is connected to the second line 66 side ( Second current mode). If the second predetermined value at which the second breaker 62 is activated is set to a value that limits the output of the robot to such an extent that it does not harm humans even if the robot runs away, a current limit signal is sent. Since the current from the power supply 16 does not exceed the second predetermined value, the safety of the human in the robot operation area is ensured. On the other hand, the first predetermined value may be determined based on the specifications of the robot, avoidance of failure, etc., and is normally set so that the robot is supplied with a current that can operate at full load, that is, at maximum output.

  The current limiting unit 50c according to the third specific example illustrated in FIG. 5C includes a resistor or resistor 70, a first line 72 that does not allow the current from the power source 16 to pass through the resistor 70, and the current from the power source 16 as a resistor. And a switch 76 capable of switching between the first line 72 and the second line 74. In the example of FIG. 5c, the switch 76 is connected to the first line 72 side when the human has not entered the robot operation area, that is, when the current limit signal is not sent to the current limiter 50c (first current mode). ), The current limiting unit 50c does not exhibit a current limiting function. On the other hand, when a human has entered the robot operation area, that is, when the current limit signal S is sent to the current limiter 50c (for example, the switch 76), the switch 76 is connected to the second line 74 side ( Second current mode). If the resistance value of the resistor 70 is set so that the current value from the power supply 16 is reduced so that the output of the robot is limited to such an extent that it does not harm humans even if the robot runs away, When the current limit signal is sent, the current from the power supply 16 is appropriately reduced by the resistor 70, and human safety within the robot operation area is ensured.

  Each of the current limiting units shown in FIGS. 5a to 5c limits the current value from the power source by switching the circuit, but like the current limiting unit 50d according to the fourth specific example shown in FIG. 5d. In addition, what adjusts an output current value by so-called PWM (Pulse Width Modulation) control can be used. The current limiting unit 50d has a PWM circuit 86 including a diode 80, a capacitor 82, and an inverter 84. When the current limiting signal S is not sent to the current limiting unit 50d (for example, the inverter 84), the robot operates at the maximum operating speed. A current is supplied that is operable and capable of maintaining a maximum static force (first current mode). On the other hand, when the current limiting signal S is sent to the current limiting unit 50d, the current limiting unit 50d is configured to be able to reduce the current to the control device 14 by modulating the pulse width (second current mode). ing.

  The current limiting unit 50e according to the fifth specific example shown in FIG. 5e includes a first battery 90 having a first capacity, a second battery 92 having a second capacity smaller than the first capacity, A first line 94 for sending current from the battery 90 to the control device, a second line 96 for sending current from the second battery 92 to the control device, and a first line 94 and a second line 96 are switched. Possible switch 98. In the example of FIG. 5e, the switch 98 is connected to the first line 94 side when the human has not entered the robot operation area, that is, when the current limit signal is not sent to the current limiter 50e (first current mode). ), The current limiting unit 50e does not exhibit a current limiting function. On the other hand, when a human has entered the robot operation area, that is, when the current limiting signal S is sent to the current limiting unit 50e (for example, the switch 98), the switch 98 is connected to the second line 96 side ( Second current mode). If the second capacity of the second breaker 92 is set so that the output of the robot is limited to such an extent that it does not harm humans even if the robot runs away, the current limiting signal is sent. Since the output of the robot is limited by the current from the second battery 92, human safety within the robot operation area is ensured. On the other hand, the first capacity of the first battery 90 may be determined from the specifications of the robot, avoidance of failure, etc., and is normally set so that a current that can be fully loaded by the robot is supplied to the robot.

  In the robot system having the configuration shown in FIG. 1, the control device 14, the power supply 16 and the power feeding adjustment device 18 are arranged outside the robot 12, but the robot may be a self-propelled type. For example, in the robot system 10 'shown in FIG. 6, a control device 14', a battery or power supply 16 ', a power supply adjusting device 18' and a drive unit 19 'controlled by the control device 14' are mounted on the robot 12 'itself. . The drive unit 19 'includes a traveling device for the robot 12', and therefore the robot 12 'acts as a self-propelled robot. The travel device is configured to be able to travel at the maximum travel speed in the first current mode, and to travel at a limited travel speed lower than the maximum travel speed in the second current mode. Since the functions of the other components of the robot 12 'can be the same as those described above, detailed description thereof will be omitted.

  In the robot system according to the present invention, since the power supply regulator switches the current mode to the robot without depending on the control device, it is not necessary to provide complicated means such as a safety device in the control device. Since the power supply regulator and the human detection device itself have a relatively simple structure, the present invention provides a robot system that can ensure the safety of the worker without depending on the safety structure of the control device. .

DESCRIPTION OF SYMBOLS 10 Robot system 12 Robot 14 Control apparatus 16 Power supply 18 Power supply regulator 20 Human 22 Robot operation area | region 24 Robot non-operation area | region 40 Human detection apparatus 50 Current limiting part

Claims (3)

An industrial robot, a control device that controls the industrial robot, a power supply adjuster that adjusts a current to the control device, and a human detection device that detects the presence of a human in the operation area of the industrial robot. In the robot system,
The power supply regulator is
Communication means for receiving an output signal of the human detection device;
A first current mode for supplying current that allows the industrial robot to operate at a maximum operating speed and maintain a maximum static force;
A second current mode for supplying a current for limiting the operation speed and static force of the industrial robot to a limited operation speed lower than the maximum operation speed and a limited static force lower than the maximum static force, respectively.
Switching between the first current mode and the second current mode is performed by the power feeding adjuster according to an output signal from the human detection device without using the control device.   The power supply adjuster uses the first current mode when an output signal indicating that a human has entered the operation area of the industrial robot is not received from the human detection device, and 2. The robot according to claim 1, wherein the second current mode is used when an output signal indicating that a human has entered the operation area of the robot is received from the human detection device. 3. system. The industrial robot has a traveling device for moving within a predetermined traveling area,
The travel device is operable at a maximum travel speed in the first current mode, and is limited to a limited travel speed lower than the maximum travel speed in the second current mode. The robot system described in 1.

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