JPS60168902A - Air-oil control device - Google Patents

Abstract

PURPOSE:To prevent unusual operations of an air-oil transducer by providing an oil storage reservoir in linkage with the oil chamber of the air-oil transducer and by providing the air-oil transducer with a function of automatically controlling the amount of oil each time a hydraulic actuator operates, when the hydraulic actuator is operated by use of the air-oil transducer. CONSTITUTION:An air-oil control device supplies the compressed air from a compressed air source 20 to an air-oil transducer 4A or 4B through an electromagnetic 3-position switch valve 17, and the high-pressure oil generated in this transducer 4A or 4B is fed to the forward chamber 3A or backward chamber 3B of a hydraulic actuator 1. At this time, each air-oil transducer 4 (hereinafter a suffix A or B abbreviated) is formed such a manner that it may contain displacement members 7 different in diameter to be freely slidable, providing an oil chamber 8 in a small-diameter side and air chambers 9, 10 in a large-diameter side. A ring-shaped groove 11 is formed in a hole through which the small- diameter section of the displacement member 7 located between the oil chamber 8 and the air chamber 10 slides, and this groove 11 is linked with an oil storage reservoir 12 via a flow path 13. And the oil storage reservoir 12 is connected to an oil chamber 15 via an air-vent open/close valve 14 and a check valve 15.

Description

DETAILED DESCRIPTION OF THE INVENTION This invention relates to an air-hydraulic control device G that operates a hydraulic actuator using a converter.

Conventionally, this type of air space control device was developed in U.S. Pat.
As shown in Publication No. 9, air converters are provided in the flow paths connecting to the forward movement chamber and backward movement chamber of the hydraulic actuator, and the conversion is performed by mutually supplying compressed air to the two air converters. The hydraulic actuator is operated by hydraulic pressure.

In addition, due to repeated operation, leakage of hydraulic oil between the forward and backward movement chambers of the hydraulic actuator can cause a more than allowable amount of oil to accumulate on the side of the air converter, causing malfunction. The oil chambers of the individual space converters are communicated with each other via an on-off valve so that the amount of oil can be adjusted. However, the opening/closing valve must be operated while visually checking the oil level, which has the disadvantage of complicating maintenance.

The present invention eliminates these drawbacks and provides a cavity control device that can optimally adjust the amount of oil in a cavity converter each time a hydraulic actuator operates.

For this reason, the present invention provides an electro-hydraulic converter on the forward-moving side that connects the oil chamber to the forward-moving chamber of the hydraulic actuator, and an electro-hydraulic converter on the backward-moving side that connects the oil chamber to the backward-moving chamber of the hydraulic actuator. ,
An electro-hydraulic converter consists of a displacement member that is displaced by the acting force of compressed air and discharges hydraulic oil from an oil chamber, an oil storage tank that stores the hydraulic oil, and an oil storage tank that is installed in a flow path that communicates between the oil storage tank and the oil chamber. It is equipped with a check valve that allows flow from the tank to the oil chamber, and a flow path that communicates the oil storage tank and the oil chamber by displacing the displacement member near the displacement end on the anti-discharge side. When the hydraulic oil is discharged from the converter to the hydraulic actuator, the other electro-hydraulic converter, to which the hydraulic oil returns from the hydraulic actuator, is arranged so that the displacement member is displaced near the displacement end, and the hydraulic actuator is operated. The oil level of the electro-hydraulic converter can be automatically adjusted to the optimum level each time.

Hereinafter, one embodiment of the present invention will be described based on the drawings.

In FIG. 1, reference numeral 1 denotes a hydraulic actuator which slidably houses a piston 2 to divide a forward movement chamber 3A and a backward movement chamber 3B. 4A and 4B are electro-hydraulic converters, in which displacement members 7A and 7B of different diameters are slidably housed, and an oil chamber 8 is provided on the small diameter side.
A, 8B on the large diameter side air chamber 9A, IOA/9B, IOB
are divided respectively, and the displacement member 7 is moved by the acting force of compressed air.
It is provided so that the hydraulic oil in the oil chambers 8A and 8B can be discharged by displacing A and 7B. And an electro-oil converter 4A.

4B is oil chamber 8A, 8B + oil outflow inlet 6A, 6B
is connected to the forward motion chamber 3A and backward motion chamber 3B of the hydraulic actuator 1 via flow paths 5A and 5B. IIA, II
B is an annular groove formed by enlarging a part of the inner periphery of the hole in which the small diameter portion of the displacement member 7A, 7B slides between the oil chamber 8A, 8B and the air chamber 10A, IOB. , 7B are displaced near the displacement end on the anti-discharge side and communicated with the oil chambers 8A and 8B. 12A and 12B are oil storage tanks for storing hydraulic oil, which are connected to the annular groove 11 through channels 18A and 13B.
It communicates with A and 11B. 14A, 14. B is an on-off valve for venting air, and is used for oil chambers 8A, 8B and oil storage tank 12.
It is provided in a flow path that communicates between A and 12B. 15A, 1
5B is a check valve and oil chamber 8A.

A flow path communicating between the oil storage tank 8B and the oil storage tanks 12A, 12B is provided to allow oil to flow from the oil storage tanks 12A, 12B to the oil chambers 8A, 8B. 16A and 16B are oil fill ports that also serve as air breathers. 17 is a solenoid valve with switching positions A, N, and B, and an air chamber 9A of two electro-hydraulic converters 4A and 4B.
, 9B via channels 18A, 18B, and the channels 18A, 18B have branch channels 19B, 19A, and are connected to the air chambers 10B, IOA of the electro-hydraulic converters 4B, 4A, respectively. It's communicating. 20 is a compressed air source, 21A, 2
1B is a silencer, 22A, 22B, 23A.

23B is a flow control valve made of check valve material.

Next, the operation of this configuration will be explained. In the illustrated state, the solenoid valve 17 is in the neutral switching position N, blocking each flow path 18A, 18B, and the displacement member 7A of the electro-hydraulic converter 4A is at the displacement end on the non-discharge side, and the electro-hydraulic converter 4B is at the displacement end. The displacement member 7B is located at the displacement end on the discharge side, and the piston 2 of the hydraulic actuator 1 is located on the forward movement chamber 3A side.

When the solenoid valve 17 is operated to the switching position B, the compressed air source 20
The compressed air from the air enters the air chamber 9A of the electro-hydraulic converter 4A via the flow path 18A, and is further throttle-controlled by the flow control valve 28B via the branch flow path 19B to the air chamber 10B of the electro-hydraulic converter 4B.
supplied to In addition, the compressed air in the air chamber 10A of the electro-hydraulic converter 4A is transferred to the outside through the check valve of the flow control valve 23A and the branch flow path 19A, and the air chamber 9B of the electro-hydraulic converter 4B.
The compressed air is discharged to the outside via the flow path 18B. Then, the displacement member 7A of the electro-hydraulic converter 4A is displaced toward the discharge side by blocking the annular groove 11A and the oil chamber 88 due to the force exerted by the compressed air in the air chamber 9A, and the hydraulic oil in the oil chamber 8A is transferred to the displacement member. 7
The pressure is increased according to the difference in the pressure receiving area of A, and the oil inflow and outflow hole 6A flow path 5
It is supplied to the reciprocating chamber 3A of the hydraulic actuator 1 through the check valve of the A flow control valve 22A, causing the piston 2 to reciprocate to the left in the figure. The hydraulic actuator 1 is displaced toward the opposite discharge side due to the acting force of the hydraulic oil in the reciprocating chamber 3B and the compressed air supplied to the air chamber 10B, and near the displacement end, the oil chamber 8B is moved through the annular groove 11B and the flow path 13B. and communicates with the oil storage tank 12B.

Next, when the solenoid valve 17 is operated to the switching position @A, the flow path 18B
The flow path 18A is switched to communicate with the compressed air source 20 to the outside, and the displacement members 7A, 7B and the piston 2 operate in the opposite direction to the state shown in the figure.

In this operation, the displacement member 7A is displaced toward the anti-discharge side.
Even if there is an increase in hydraulic fluid in the forward motion chamber 3A due to leakage from the backward motion chamber 3B, after the displacement member 7A is displaced toward the opposite discharge side, G will further increase and the T hydraulic fluid will be transferred to the oil chamber 8A. The oil flows out through the annular groove 11A and the flow path 13A to the oil storage tank 12A, and the hydraulic actuator 1 can be operated regardless of leakage.

Also, after displacing the displacement member 7B to the opposite discharge side, there is a possibility that the hydraulic oil will decrease in the backward movement chamber 3B due to leakage into the forward movement chamber 3A.
However, the displacement member 7B transfers the hydraulic oil from the reciprocating chamber 3B to the oil chamber 8.
Even if the oil chamber 8A and the annular groove 11B are not in communication with each other, the hydraulic oil in the oil storage tank 12B is transferred to the check valve 15B.
The oil flows into the oil chamber 8B through the oil chamber 8B, and the displacement member 7B is forcibly displaced to the displacement end on the anti-discharge side, so that the hydraulic actuator 1 can be operated thereafter regardless of the leakage. The on-off valves 14A and 14B are opened when the device is operated and are opened when air accumulated in the oil chambers 8A and 8B is removed.

FIG. 2 shows another embodiment, and nine main points of difference from FIG. 1 will be explained. 81A and BIB are displacement members with the same diameter, and oil chamber 32A
, 82B and the air chambers 88A, 33B, and the displacement members 81A, 31B are housed in the oil chambers 32A, 32B, and the air chambers 83A, 33B are moved by the force of the springs 34A, 34B.
It is housed so that it can be forcibly displaced toward the oil chambers 82A, 32B by the acting force of the compressed air supplied to the air chambers 83A, 33B. 85A, 85B are oil chambers 32A,
Displacement members 31A, 8 between 32B and air chambers 33A, 33B
An annular groove formed by enlarging a part of the inner periphery of the hole in which 1B slides, so that when the displacement members 81A and 31B are displaced to the displacement end on the anti-discharge side, they communicate with the oil chambers 32A and 32B. It is set up. 36 is a flow path 8 that communicates between the oil storage tanks 12A and 12B.
Reference numerals 7A and 87B indicate flow control valves made of check valve material installed in the flow paths 18A and 18B, which control the air discharged to the outside from the air chambers 88A and 33B.

In this configuration, the displacement members 31A and 31B of the two air space converters 4A and 4B are connected to the air chamber 38A by the solenoid valve 17.
, 83B, compressed air is supplied to the air chambers 38A, 83B,
When the compressed air of 8B is discharged to the outside and becomes stiff, it is displaced by the opposing action of the acting force of the compressed air and the forces of the springs 34A and 34B, and the hydraulic pressure discharged to the hydraulic actuator 1 is supplied to the air chambers 33A and 33B. The pressure is the same as that of compressed air. And the oil storage tank 12A is connected to the flow path 36.

12B are in communication, so there is a space converter on the forward side that connects the oil chamber to the oil storage tank 12A and chamber 1, and a space converter on the backward side that connects the oil chamber to the backward movement chamber of the hydraulic actuator. The air converter includes a displacement member that is displaced by the acting force of compressed air and discharges hydraulic oil from the oil chamber, an oil storage tank that stores the hydraulic oil, and a flow path that communicates between the oil storage tank and the oil chamber. The oil storage tank is provided with a check valve that allows flow from the oil storage tank to the oil chamber, and a flow path that communicates the oil storage tank and the oil chamber by displacing the displacement member to the vicinity of the displacement end on the opposite discharge side, When discharging hydraulic oil from one air transducer to the hydraulic actuator, the other air transducer to which the hydraulic oil from the hydraulic actuator returns is arranged so that the displacement member is displaced near the displacement end. From G Koyori,
The amount of oil in the pneumatic converter can be adjusted to the optimum amount each time the hydraulic actuator operates, and if the hydraulic actuator is in good condition, the operation can be controlled for a long period of time, and maintenance management can be simplified. Further, even when changing the reciprocating length of the hydraulic actuator to a shorter length, the oil amount can be adjusted to the optimum level without changing the air converter.

[Brief explanation of drawings]

The drawings are circuit diagrams partially showing an embodiment of the present invention in cross section, with FIG. 1 showing one embodiment and FIG. 2 showing another embodiment. 1-m-hydraulic actuator, 3A--one forward movement chamber, 3B
--One reciprocating chamber, 4A, 4B--One air-oil converter, 7A, 7
B, 31A, 81 B-m-displacement member, 8A, 8B, 8
2A, 32B-m-oil chamber, 12A, 12T3--1 oil storage tank. Patent applicant Toyoko Kogyo Co., Ltd. Figure 1 1

Claims (1)

[Claims] A space converter on the forward side that connects the oil chamber to the forward motion chamber of the hydraulic actuator and a space converter on the backward motion side that connects the oil chamber to the backward motion chamber of the hydraulic actuator are provided. , a displacement member that is displaced by the acting force of compressed air and discharges hydraulic oil from the oil chamber, a storage tank that stores the hydraulic oil, and a flow path that communicates between the oil storage tank and the oil chamber from the oil storage tank to the oil chamber. When discharging hydraulic fluid from one pneumatic transducer to the hydraulic actuator, the other pneumatic transducer, to which the hydraulic fluid from the hydraulic actuator returns, has a check valve that allows the displacement member to move close to the displacement. A space control device that is arranged so that it can be displaced.