JPH10296678A - Cooling system for robot control panel - Google Patents

Abstract

PROBLEM TO BE SOLVED: To make effective use of regenerative energy by cooling the inside of a robot control panel or heating parts to be used by using regenerative energy, or by cooling the cooling medium of a welding apparatus to be used in a welding robot. SOLUTION: This robot is constituted so as to be driven by a servomotor. It involves a regenerative current controller 2 for taking out regenerative energy as electric power, which is generated to operate as a generator at the time of deceleration, and a cooling means 10 which supplies the regenerative power taken out from the regenerative current controller 2 to a cooling device 3 in a robot control panel 4, or a welding apparatus cooling medium heat removing device in the robot control panel and cool it.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method for utilizing regenerative energy of an industrial robot using an electric servomotor, and more particularly, to a cooling system for a heat-generating component inside or used in a robot control panel using regenerative energy, and welding. The present invention relates to a cooling system for cooling a cooling medium of a welding device used in a robot.

[0002]

2. Description of the Related Art As shown in FIG. 3, when an industrial robot is operated, a current is supplied to a drive motor in an acceleration unit.
The deceleration unit uses a motor to absorb the kinetic energy of the operating robot and brakes it. Therefore, the motor functions as a generator and generates electric power. The power generated by this motor is called regenerative energy or regenerative power.

As a means for absorbing this regenerative energy, for example, as shown in FIG. 4, it is common to convert it into heat using a resistor and radiate it to the atmosphere. The regenerative energy generated by the servo motor 12 for driving the industrial robot flows into the motor drive circuit via an element called a freewheel diode of the power module 13 for driving the motor, and the power supply voltage (P −N voltage). If this voltage rise value becomes too large, the motor drive circuit will cause breakdown voltage. For this reason, the power supply voltage PN of the motor drive circuit is monitored by the voltage detection circuit 14, and when the power supply voltage PN exceeds a specified value,
The power transistor circuit 15 is driven and the discharge resistor 16
To convert regenerative energy into heat. Thereby, regenerative energy is consumed and the power supply voltage of the motor drive circuit is maintained at the normal voltage.

[0004]

In the above-described method, regenerative energy is radiated to the atmosphere as heat energy, so that energy is wasted and the reliability of the robot is reduced due to a rise in the temperature of the radiating peripheral portion. It was with.
Also, for example, as disclosed in JP-A-6-15590,
In order to prevent the discharge resistor from being destroyed due to excessive operation, the operation of the robot was sometimes restricted.

In order to avoid such a problem, Japanese Patent Application Laid-Open No. 7-123731 discloses that a regenerative energy is supplied to an AC power supply R- on the primary side via an intelligent power module.
A proposal to revert to ST is disclosed. As a result, a discharge resistor is not required, and waste of energy there can be eliminated. However, in order to return to the primary side AC power supply, while monitoring the voltage waveform of each phase of the three-phase sine wave AC,
A complicated control circuit for determining which phase to return to and a switching circuit are required. On the other hand, a three-phase sine is used to return power to the primary AC power supply at irregular timing depending on the operation of the robot. This causes a problem that the waveform of the wave is distorted and the phases of the current and the voltage are shifted. Such a waveform distortion or phase shift lowers the power factor of other connected control equipment, and as a result, the energy efficiency of the entire factory does not increase. In particular, when starting a line in which the robots start operating at the same time, regenerative power is returned from many robots at the same time, so that the power supply of the factory becomes extremely unstable.

As described above, in the conventional circuit using the discharge resistor for regenerative energy discharge, energy is wasted, and the heat-generating portion causes a reduction in reliability. Also,
In a circuit that returns regenerative energy to the primary side AC power supply, the circuit configuration is complicated, and the quality of the power supply in the factory deteriorates.
There was a problem that energy efficiency did not increase in the whole factory.

SUMMARY OF THE INVENTION The present invention has been made to solve the above-mentioned problems of the prior art, and has a simple circuit configuration without deteriorating the quality of a power supply in a factory and has a regenerative energy of an industrial robot. The purpose of the present invention is to provide a system for effectively utilizing the system.

[0008]

In order to achieve the above object, according to the present invention, regenerative energy generated during operation of an industrial robot is used to cool the inside of a robot control panel or a heat-generating component to be used. By utilizing the cooling medium of the welding equipment used in the welding robot as an energy source for cooling, a means for stably utilizing regenerative energy is provided.

That is, according to the first aspect of the present invention, in an industrial robot driven by a servomotor, a regenerative current control device for extracting regenerative energy generated as the servomotor operates as a generator during deceleration as electric power. The problem of the related art described above has been solved by providing a cooling system including cooling means for supplying regenerative electric power extracted from the regenerative current control device to a cooling device in a robot control panel for cooling.

With this configuration, the inside of the robot control panel or the heat-generating component to be used is cooled using the regenerative energy. Generally, the amount of heat generated inside the robot control panel or the heat generating components used increases in proportion to the energy input in the acceleration unit of the robot. On the other hand, the regenerative energy generated in the deceleration unit also increases in proportion to the input energy, and the cooling capacity of the cooling unit using this regenerative energy also increases. Therefore, the greater the amount of heat generated inside the robot control panel or the heat-generating components used, the greater the cooling capacity of the cooling unit, and the lower the basic cooling capacity when the robot is not operating. It also has the advantage of being able to provide efficient cooling capacity.

According to the second aspect of the present invention, in an industrial robot driven by a servo motor, a regenerative current control device for extracting regenerative energy generated by the servo motor operating as a generator during deceleration as electric power. In addition, a cooling system for a control panel comprising cooling means for supplying regenerative electric power taken out from the regenerative current control device to a cooling medium heat removal device for welding equipment in a robot control panel to cool it is provided. As a result, the regenerative energy can be effectively used for cooling the welding equipment used in the welding robot.

According to a third aspect of the present invention, in the first or second aspect of the invention, the regenerative current control device includes a voltage detection circuit for a servo motor driving power supply, a power transistor circuit driven by the voltage detection circuit, The configuration was made up of a capacitor circuit charged by a transistor circuit. The capacitor circuit includes a battery circuit that can be regarded as a large-capacity capacitor. Thereby, the regenerative energy is accumulated in the capacitor and gradually discharged, so that the regenerative energy can be smoothed and used as a power source for cooling.

[0013]

Embodiments of the present invention will be described below with reference to the drawings. FIG. 1 is a diagram showing a system configuration of a control panel cooling device using regenerative energy of a robot according to an embodiment of the present invention. FIG. 2 is a diagram showing a system configuration of a welding machine cooling medium heat removal apparatus in a robot control panel using regenerative energy of a robot in another embodiment of the present invention.

As shown in FIG. 1, a servo motor 1 for driving a robot uses a servo motor driving power source 5 for converting a three-phase alternating current to a direct current power source by a known motor driving circuit (not shown in FIG. 1). Receive via module 6 and rotate. In the acceleration section shown in FIG. 3, power is thus supplied to the servo motor 1 and the servo motor 1 is accelerated. At the time of deceleration, the servo motor 1 becomes a generator, and the regenerative power is returned in the direction shown by the arrow in FIG. 1 and is applied to the servo motor drive power supply 5 via the freewheel diode of the power module 6 to increase the power supply voltage. . At this time, the power supply voltage is monitored by a voltage detection circuit 7 in the regenerative current control device 2, and when the power supply voltage exceeds a preset value, the power transistor circuit 8 is driven and the regenerative power is supplied to the capacitor circuit 9. Charge. By charging the capacitor circuit 9 with the regenerative energy generated by the servo motor 1 in this manner, the voltage of the servo motor drive power supply 5 decreases, and the power transistor circuit 8 is closed by a command from the voltage detection circuit 7.

The regenerative electric power charged in the capacitor circuit 9 is supplied to the cooling means 10, and is supplied to the cooling means 10 through the heat exchange plate 11 of the cooling device 3 in the robot control panel 4. Releases heat into the atmosphere. The heat exchange plate 11 is usually formed of a thin aluminum plate to form a radiation fin,
Bending is performed so that heat exchange is performed efficiently. The cooling means 10 generally uses a fan motor. The heat in the robot control panel 4 is transmitted to the heat exchange plate 11 by a fan motor in the robot control panel 4, and the heat exchange plate 11 is blown by the fan motor outside the robot control panel 4 to blow the heat to the heat exchange plate 11. As a result, the heat in the robot control panel 4 is released to the atmosphere. As the cooling means 10, in addition to the fan motor, an element utilizing the Peltier effect for converting current to heat may be used, and the cooling means 10 may be directly cooled by regenerative power. Alternatively, it is also possible to use an aluminum heat sink called a heat sink as the heat exchange plate 11 and attach the power module 6 to this heat sink to cool the heat generated by the power module 6.

FIG. 2 shows another embodiment of the present invention.
1 shows a system configuration of a cooling medium heat removal apparatus for welding equipment in a robot control panel using regenerative energy of a robot. Until the regenerative power is charged in the capacitor circuit 9, the operation is the same as that of the embodiment shown in FIG. In the drawing, reference numeral 17 denotes a cooling medium heat removal device in the robot control panel, and a welding device 18 means, for example, a welding gun for spot welding. In this welding gun for spot welding, the heat generated during welding is cooled using tap water. The tap water used as the cooling medium is circulated by a cooling medium circulating pump 19 through a heat removal device 20 composed of, for example, a radiator, and the cooling means 1 such as a fan motor is used.
0 cools the cooling medium. Thus, it is possible to remove the heat of the cooling medium of the welding equipment by the regenerative electric power.

[0017]

According to the present invention, the regenerative energy generated during the operation of an industrial robot is used to cool the inside of a robot control panel or a heat-generating component to be used, or a cooling medium for welding equipment used in a welding robot. The regenerative energy generated during the operation of the industrial robot can be effectively used without deteriorating the quality of the power supply at the factory, and with a simple circuit configuration. Became possible. Further, in the present invention, there is an advantage that the larger the amount of heat generated inside the robot control panel or the heat-generating components used, the larger the cooling capacity of the cooling unit, and the lower the basic cooling capacity when the robot is not operating. Since it also has the advantage of being able to be set, it is possible to provide an efficient cooling capacity for the heating element of the industrial robot.

[Brief description of the drawings]

FIG. 1 is a diagram showing a system configuration of a control panel cooling device using regenerative energy of a robot according to an embodiment of the present invention.

FIG. 2 is a diagram illustrating a system configuration of a cooling medium heat removal device for welding equipment in a robot control panel using regenerative energy of a robot in another embodiment of the present invention.

FIG. 3 is a diagram showing speeds at the time of acceleration and deceleration of the robot.

FIG. 4 is a diagram showing a system configuration in a conventional example in which regenerative energy of a robot is consumed by discharge resistance.

[Explanation of symbols]

 1,12 (for driving a robot) Servo motor 2 Regenerative current control device 3 Cooling device in robot control panel 4 Robot control panel 5 Servo motor drive power supply 6,13 Power module 7,14 Voltage detection circuit 8,15 Power transistor circuit 9 Capacitor Circuit 10 Cooling means 11 Heat exchange plate 16 Discharge resistance 17 Cooling medium heat removal device in robot control panel 18 Welding equipment 19 Cooling medium circulation pump 20 Heat removal device

Continuation of the front page (71) Applicant 000000974 Kawasaki Heavy Industries, Ltd. 3-1-1, Higashi-Kawasaki-cho, Chuo-ku, Kobe-shi, Hyogo (72) Inventor Masaru Sakai 1-1-1, Fujikoshi-Honmachi, Toyama-shi, Toyama Fujitsukoshi (72) Inventor Kiyoshi Kaniya 1-1-1, Fujikoshi Honcho, Toyama City, Toyama Prefecture Fujiuchi Co., Ltd. (72) Inventor Kazushige Suita 1 Toyota Town, Toyota City, Aichi Prefecture Toyota Motor Corporation (72) Inventor Yoshitaka Sakamoto 1 Toyota Town, Toyota City, Aichi Prefecture Toyota Motor Corporation (72) Inventor Kuniyuki Niwa 1-1-1, Asahimachi, Kariya City, Aichi Prefecture Toyota Industries Co., Ltd. (72) Inventor Akira Uchida Aichi 1-1-1 Asahi-cho, Kariya, Japan Toyota Motor Corporation (72) Inventor Toshiaki Yoshida 1-1, Kawasaki-cho, Akashi-shi, Hyogo Kawasaki Heavy Industries, Ltd.

Claims (3)

[Claims] An industrial robot driven by a servomotor, a regenerative current control device for extracting regenerative energy generated by the servomotor operating as a generator during deceleration as electric power, and an extractor from the regenerative current control device. A cooling system for a robot control panel, comprising cooling means for supplying regenerated electric power to a cooling device in the robot control panel for cooling. 2. An industrial robot driven by a servomotor, a regenerative current control device for extracting regenerative energy generated when the servomotor operates as a generator during deceleration as electric power, and an output from the regenerative current control device. A cooling system for a robot control panel, comprising cooling means for supplying regenerative power to a cooling medium heat removal device for welding equipment in the robot control panel for cooling. 3. The regenerative current control device comprises a servo motor drive power supply voltage detection circuit, a power transistor circuit driven by the voltage detection circuit, and a capacitor circuit charged by the power transistor circuit. The cooling system for a robot control panel according to claim 1.