JPS5923956B2 - Hand control method - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a system for controlling the motion of an industrial robot's hand, and in particular, when the opening and closing motion of the fingers of the motion hand is controlled using a fluid pressure actuator such as an air cylinder, an electric control circuit is used. The present invention relates to a hand control system capable of controlling the hand fingers to maintain the opened/closed state before the occurrence of a certain condition in a fluid pressure circuit.

The hands of industrial robots are generally used to grasp and transport heavy objects, but when the opening and closing operations of the fingers of the hands are controlled using fluid pressure actuators such as air cylinders, there is a risk of power failure or power outage accidents in the electrical control circuit. Even if a situation occurs such as power supply turning on or power restoration, or fluid pressure cutoff or restoration in the fluid pressure circuit, the fluid pressure actuator operates accordingly, and the opening/closing operation state of the fingers of the hand changes. It is necessary to prevent the hand from falling and maintain the previous state, and similarly to prevent the object from falling by the hand.

An object of the present invention is to provide a simple hand control system for controlling the hand so as to satisfy such needs.

That is, according to the present invention, the operation of the first and second electromagnetic directional control valves provided between the fluid pressure source and the fluid pressure actuator and the third electromagnetic directional control valve provided in the fluid pressure discharge path is controlled. In the second control method, the electromagnetic valve operates the third electromagnetic directional control valve in synchronization with the operation of the first or second electromagnetic directional control valve. A hand control system is provided that is characterized by providing a valve control circuit. Hereinafter, the present invention will be described in detail based on embodiments shown in the accompanying drawings. FIG. 1 shows the structure according to the present invention.
- This is a circuit showing an example of a fluid pressure circuit for implementing the control method of the 2nd control system, and particularly shows an example in which an air cylinder is used as a fluid pressure actuator.

Further, Fig. 2 is a circuit diagram of a solenoid valve control circuit that controls the operation of the electromagnetic directional control valve in the fluid pressure circuit of Fig. 1, and Fig. 3 simply shows the features of the hand control system according to the present invention. It is a graph diagram. In FIG. 1, 10 is a double-acting air cylinder, which has cylinder chambers IOA and IOB on both sides of a piston 12, and a piston rod 14 connected to the piston 12 is connected to a finger of an operating hand (not shown). has been done. That is, the pressurized air flows into the cylinder chamber 10A.
When the piston 12 and the piston rod 14 are introduced into the cylinder chamber 10B and exhausted from the cylinder chamber 10B, the piston 12 and the piston rod 14 are
moves to apply an opening action to the finger of the operating hand, and conversely, when pressure air is introduced into the cylinder chamber 10B and exhausted from the cylinder chamber 10A, the piston 12 and the piston rod 14 move in the direction of arrow B. Move and perform the above operations.
・It gives a closing motion to the fingers of the hand, for example, to grip a heavy object. Now, reference numerals 16, 18, and 20 each represent a spring offset solenoid type two-position, three-port directional control valve, and the first valve 16 is connected to a pressure air source 22 via a line 28, and is connected to a line 30. Air cylinder 10 through
It is connected to the cylinder chamber 10A. Also, the second valve 1
8 is also connected to the pressure air source 22 via a conduit 28 and to the cylinder chamber 10B of the air cylinder 10 via a conduit 32. On the other hand, the third valve 20 exhausts pressurized air from each cylinder chamber 10A, 10B of the air cylinder 10 via the first valve 16, second valve 18, and through the respective check valves 24, 26. Exhaust pipe line 34
is connected to. The state of the fluid pressure circuit shown in Figure 1 is
- The case where the third valves 16, 18, and 20 are all in the non-operating position (off position) is shown, and when the first electromagnetic directional control valve 16 is actuated to the on position, pressure is supplied from the pressure air source 22. Air is introduced into the cylinder chamber 10A of the air cylinder 10 through the valve 16 and the conduit 30, and moves the piston 12 and piston rod 14 in the direction of arrow A. At this time, the pressurized air in the cylinder chamber 10B is discharged to the exhaust pipe 34 via the pipe 32 and the second electromagnetic directional control valve 18 which is in the OFF position, and is further synchronized with the first electromagnetic directional control valve 16. For example, it is released into the atmosphere through the third electromagnetic directional control valve 20 which is operated by the pump. On the other hand, the piston 1 of the air cylinder 10
2 and the piston rod 14 in the direction of arrow B, the first electromagnetic directional control valve 20 is turned off and the second electromagnetic directional control valve 18 is operated, and in synchronization with this, the third electromagnetic directional control valve 18 is activated. If the valve 20 is also operated to the on position, the pressure air source 2
Pressure air is introduced into the cylinder chamber 10B from the cylinder chamber 10A, and the pressure air is discharged to the atmosphere from the cylinder chamber 10A, resulting in the desired movement of the piston 12 and piston rod 14. A solenoid valve control circuit for controlling the operations of the first, second, and third solenoid directional control valves 16, 18, and 20 as described above can be configured as shown in FIG. That is,
16a, 18a, and 20a are solenoids for the first to third valves 16, 18, and 20, respectively, and among these, the solenoids 16a and 18a are connected to an excitation circuit having transistors 36 and 38 whose emitters are grounded, respectively. has been done. Further, the solenoid 20a is connected to each of the above excitation circuits via diodes 42 and 44.
Vs is a power source for the solenoid valve. In such a solenoid valve control circuit, when the transistor 36 is turned on, the solenoid 16a is energized, and in synchronization with this, the diode 4 is energized.
2, solenoid 20a is also energized, and solenoid directional control valves 16 and 20 are actuated synchronously to the on position as described above with respect to FIG. On the other hand, when the transistor 38 is turned on, the solenoid 18a is energized, and in synchronization with this, the solenoid 20a is also energized via the diode 44, and the electromagnetic directional control valves 18 and 20 in FIG. 1 are synchronously moved to the on position. It will be activated. FIG. 3 is a time chart showing how the first electromagnetic directional control valve 16 or the second electromagnetic directional control valve 18 and the third electromagnetic directional control valve 20 are operated synchronously. Now, according to the circuit configurations shown in Figs. 1 and 2, even if various conditions such as power cutoff, power outage, power on, power restoration, pressurized air cutoff, and restoration as described above occur, they will not occur. Both transistors 36 and 38 are in an off state before and after. For this purpose, solenoids 16a, 18a
, 20a are not energized, and as a result, the first, second, and third electromagnetic directional control valves 16, 18, 20
is never activated. That is, when the third electromagnetic directional control valve 20 is in the off position, the pressure air from either cylinder chamber 10A or 10B of the air cylinder 10 is confined in the fluid pressure circuit so that it cannot be released into the atmosphere. In the cylinder 10, a piston 12 and a piston rod 14
and is moved in the arrow A direction or the arrow B direction. Therefore, for example, air cylinder 1
If the piston 12 and piston rod 14 of No. 0 are moved in the direction of arrow B and the fingers of the operating hand are grasping a heavy object, this grasping state will continue even before and after the above-mentioned conditions such as power cutoff occur. This will prevent heavy objects from falling. 1 and 2 have been described with reference to an embodiment in which the pressure fluid is composed of pressure air and the fluid pressure actuator for driving the operating hand is composed of an air cylinder. It goes without saying that the objects and effects of the present invention can be achieved in exactly the same manner even in embodiments in which the fluid pressure actuator is constructed with an air motor or a hydraulic motor.

[Brief explanation of the drawing]

FIG. 1 is a circuit diagram showing one embodiment of a fluid pressure circuit for implementing the hand control method according to the present invention, FIG. 2 is a circuit diagram of a solenoid valve control circuit related to FIG. 1, and FIG. FIG. 3 is a graph diagram for explaining the effects of the present invention.

Claims (1)

[Claims] 1. A first device provided between a fluid pressure source and a fluid pressure actuator.
, in a hand control method that controls the operating direction of the operating hand by controlling the operation of the second electromagnetic directional control valve and the third electromagnetic directional control valve provided in the fluid pressure discharge path; A hand control system comprising a solenoid valve control circuit that operates the third solenoid directional control valve in synchronization with the operation of the second solenoid directional control valve. 2. In the hand control system according to claim 1, the electromagnetic valve control circuit connects the third electromagnetic directional control valve to the excitation operation circuit of the first and second electromagnetic directional control valves via diodes, respectively. A hand control system that connects an excitation operating circuit. 3. In the hand control system according to claim 1, the first, second, and third electromagnetic directional control valves are two-position three-port valves, and the fluid pressure actuator is a double-acting cylinder. A new hand control system.