JPH0228724B2 - KUYUSEIGYOSOCHI - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to an air-hydraulic control device that reciprocates a hydraulic actuator using an air-hydraulic converter that converts compressed air pressure into hydraulic pressure.

[Conventional technology]

Conventionally, this type of air-hydraulic control device was developed in 1983.
As shown in Publication No. 71199, the hydraulic actuator is equipped with an air-oil converter connected to the forward movement chamber and the backward movement chamber, and the two air-oil converters are operated by alternately supplying compressed air, thereby reducing the oil pressure. The hydraulic actuator is reciprocated by hydraulic fluid discharged from the chamber. During the repeated operation of the two air-hydraulic converters, a pressure difference occurs between the forward motion chamber and backward motion chamber of the hydraulic actuator due to the load acting on the piston of the hydraulic actuator, and the piston sliding portion is moved from the high pressure side. In order to prevent this, hydraulic oil leaks to the low pressure side and the oil level in the oil chamber of the air-oil converter increases or decreases beyond the permissible value over a long period of operation, causing malfunction of the hydraulic actuator. An on-off valve is installed in the communication path that communicates between the oil chambers of the two air-oil converters, and by operating the on-off valve, hydraulic oil is supplied to the oil chamber of the air-oil converter, and hydraulic oil is discharged from the oil chamber. I am trying to adjust the oil level by doing something like this.

[Problem that the invention seeks to solve]

However, in order to adjust the oil level in the oil chamber of the air-oil converter, it is necessary to operate the on-off valve with the air-oil converter stopped, so it is necessary to adjust the oil level each time the air-oil converter is adjusted. The problem was that the operation of the equipment had to be stopped, resulting in poor operating efficiency of the equipment.

The present invention solves these problems and provides an air-oil control device that adjusts the amount of oil in the oil chamber without stopping the operation of the air-oil converter and improves the operating efficiency of the device. It is.

[Means for solving problems]

Therefore, the present invention displaces the displacement member slidably housed inside to one side to discharge the hydraulic oil in the oil chamber into the forward movement chamber of the hydraulic actuator, and at the same time displaces the displacement member to the other side. There is an air-oil converter on the forward side that allows hydraulic oil from the forward movement chamber of the hydraulic actuator to flow into the oil chamber, and a displacement member that is slidably housed inside is displaced to one side to drain the hydraulic oil in the oil chamber. The hydraulic actuator is equipped with an air-oil converter on the backward-moving side that discharges hydraulic oil into the backward-moving chamber of the hydraulic actuator and displaces the displacement member to the other side so that hydraulic oil from the backward-moving chamber flows into the oil chamber; The displacement member of the air-oil converter on the forward-moving side is displaced to one side, the displacement member of the air-oil converter on the backward-moving side is displaced to the other side, or the displacement member of the air-oil-oil converter on the forward-moving side is displaced to the other side. Compressed air is freely applied to the displacement member of each pneumatic-hydraulic converter so that the displacement member of the pneumatic-hydraulic converter on the forward-moving side and the backward-moving side is displaced to one side. The oil chamber is connected to a common single oil storage tank through each passage provided with a check valve to allow the inflow of hydraulic oil from the oil storage tank, and each air-oil converter has a displacement member. A flow path is provided which opens when the displacement member is displaced near the displacement end on the other side and communicates between the oil chamber and the oil storage tank so that the oil chamber communicates with the oil storage tank each time the displacement member is displaced toward the other side.

[Effect]

In such a configuration, when the displacement member of the forward-moving air-oil converter is displaced to one side and the displacement member of the backward-moving air-oil converter is displaced to the other side by the action of compressed air, the hydraulic actuator moves forward. Hydraulic oil is supplied to the chamber from the oil chamber of the air-oil converter on the forward-moving side, and hydraulic oil in the backward-moving chamber flows into the oil chamber of the air-oil converter on the backward-moving side and moves forward. Furthermore, when the displacement member of the air-oil converter on the backward-moving side is displaced to one side and the displacement member of the air-oil converter on the forward-moving side is displaced to the other side by the action of compressed air, the hydraulic actuator moves into the double-acting chamber. Hydraulic oil is supplied from the oil chamber of the pneumatic-oil converter on the backward-moving side, and hydraulic oil in the forward-moving chamber flows into the oil chamber of the air-oil converter on the forward-moving side for backward movement.
The air-oil converter, in which the amount of oil in the oil chamber increases due to leakage of hydraulic oil between the forward and backward movement chambers of the hydraulic actuator, has a flow path that opens when the displacement member is displaced near the other displacement end. The increased amount of hydraulic oil is discharged to the oil storage tank via the . In addition, in air-hydraulic converters, where the amount of oil in the oil chamber decreases due to leakage of hydraulic oil between the forward and backward movement chambers of the hydraulic actuator, the amount of oil in the oil chamber decreases due to displacement of the displacement member toward the other side. Due to the amount, the pressure becomes negative, and the hydraulic oil in the oil storage tank flows into the oil chamber via the check valve. Therefore, by operating the air-oil converter, the increased amount of hydraulic oil in the oil chamber can be discharged to the oil storage tank, and the decreased amount of hydraulic oil in the oil chamber can flow from the oil storage tank, so the operation of the air-oil converter can be stopped. The amount of oil in the oil chamber can be adjusted without causing any damage, and the operating efficiency of the device can be improved.

〔Example〕

Hereinafter, one embodiment of the present invention will be described based on the drawings. Reference numeral 1 denotes a hydraulic actuator which slidably houses a piston 2 and divides it into a forward movement chamber 3A and a backward movement chamber 3B. 4A and 4B are air-oil converters, in which displacement members 7A and 7B of different diameters are slidably housed to form oil chambers 8A and 8B on the small diameter side, and air chambers 9A and 8B on the large diameter side. 10A, 9B, and 10B are divided. The air-oil converter 4A is connected to the forward movement chamber 3A of the hydraulic actuator 1 via an oil outlet 6A provided in the oil chamber 8A and a flow path 5A, and is displaced by the acting force of compressed air supplied to the air chamber 9A. By displacing the member 7A to one side in the axial direction, the hydraulic oil in the oil chamber 8A is discharged to the forward movement chamber 3A, and the force of the compressed air supplied to the air chamber 10A causes the displacement member 7A to move to the other side in the axial direction. It is provided so that the hydraulic oil in the forward movement chamber 3A flows into the oil chamber 8A by displacement. In addition, the air-oil converter 4B has an oil outflow inlet 6B provided in the oil chamber 8B.
is connected to the reciprocating chamber 3B of the hydraulic actuator 1 via the flow path 5B, and the displacement member 7B is displaced to one side in the axial direction by the acting force of the compressed air supplied to the air chamber 9B, thereby operating the oil chamber 8B. By displacing the displacement member 7B to the other side in the axial direction by the acting force of compressed air that discharges oil into the reciprocating chamber 3B or supplies it to the air chamber 10B, the hydraulic oil in the reciprocating chamber 3B flows into the oil chamber 8B. It is set up like this. 11A and 11B are the oil chambers 8A and 8B and the air chamber 10 of each air-oil converter 4A and 4B.
The annular groove is formed by enlarging a part of the inner periphery of the hole in which the small diameter portion of the displacement members 7A and 7B between A and 10B slides, and the displacement members 7A and 7B are displaced to the vicinity of the displacement end on the other side. It is provided so as to open when necessary and communicate with the oil chambers 8A and 8B. 12 is a single oil storage tank for storing hydraulic oil, and the annular groove 11 of each air-oil converter 4A, 4B
Channels 13A and 13B connected to A and 11B
is connected to. 15A, 15B are oil chambers 8A, 8
This is an on-off valve for venting air from oil chamber 8A,
Flow paths 14A, 14 communicating between 8B and the oil storage tank 12
It is located in B. Check valves 16A and 16B are arranged in parallel with the on-off valves 15A and 15B of the flow paths 14A and 14B to allow hydraulic oil to flow from the oil storage tank 12 into the oil chambers 8A and 8B. Reference numeral 17 denotes an oil filler port provided in the oil storage tank 12 that also serves as an air breather.
18 is a solenoid valve having switching positions A, N, and B;
It is connected to the air chambers 9A, 9B of the air-oil converters 4A, 4B via channels 19A, 19B, and branch channels 20B, 20 branch from the channels 19A, 19B.
It is connected to air chambers 10B and 10A of opposing air-oil converters 4B and 4A via A. Then, the solenoid valve 18 is at the switching position B to supply compressed air to the air chambers 9A and 1.
0B, open the air chambers 9B and 10A to the atmosphere, and displace the displacement member 7A to one side, thereby displacing the displacement member 7B.
is displaced to the other side, and at the same time, compressed air is supplied to the air chambers 9B and 10A at the switching position A.
0B is opened to the atmosphere, the displacement member 7A is displaced to the other side, and the displacement member 7B is displaced to one side, and compressed air is freely applied to each displacement member 7A, 7B. 21 is a compressed air source, 22A, 22
B is a muffler, and 23A, 23B, 24A, and 24B are flow control valves with check valves provided in the channels 5A, 5B and the branch channels 20A, 20B.

Next, the operation of this configuration will be explained. In the illustrated state, the solenoid valve 18 is in the neutral switching position N, and the flow path 19A
and 19B, the displacement member 7A of the pneumatic-oil converter 4A is at the other displacement end, the displacement member 7B of the pneumatic-oil converter 4B is at the one displacement end, and the piston 2 of the hydraulic actuator 1 is at the forward displacement end. It is located on the moving room 3A side.

Now, when the solenoid valve 18 is switched to the switching position B from the illustrated state, the compressed air from the compressed air source 21 flows through the flow path 19A, is supplied to the air chamber 9A of the air-oil converter 4A, and moves the displacement member 7A to one side. The compressed air that is displaced and further flows through the flow path 19A flows through the branch flow path 20B, is throttle-controlled by the flow rate control valve 24B, and is supplied to the air chamber 10B of the air-oil converter 4B, displacing the displacement member 7B to the other side. In addition, each displacement member 7A, 7B
With the displacement of the air chamber 10 of the air-oil converter 4A
The compressed air of A goes through the branch flow path 20A and the flow rate control valve 24.
The compressed air in the air chamber 9B of the air-oil converter 4B flows through the flow path 19B and is discharged to the outside. Then, the displacement member 7A of the air-oil converter 4A is moved between the annular groove 11A and the oil chamber 8A by the acting force of the compressed air in the air chamber 9A.
When the gap is interrupted and the oil is displaced to one side, the pressure of the hydraulic oil in the oil chamber 8A is increased according to the difference in pressure receiving area due to the different diameters of the displacement member 7A, and the oil outflow inlet 6A, flow path 5A, and flow rate control valve 23A are checked. It flows through the valve and is supplied to the forward movement chamber 3A of the hydraulic actuator 1. The hydraulic oil in the reciprocating chamber 3B of the hydraulic actuator 1 flows through the flow path 5B, is throttle-controlled by the flow rate control valve 23B, and flows into the oil chamber 8B of the air-oil converter 4B from the oil outlet 6B, and the piston 2 moves toward the left in the figure. will be transferred to. Air-oil converter 4B
The oil chamber 8B communicates with the oil storage tank 12 via the annular groove 11B and the flow path 13B when the displacement member 7B is displaced to the vicinity of the other displacement end.

Next, when the solenoid valve 18 is switched to the switching position A, compressed air from the compressed air source 21 is supplied to the air chamber 9B of the air-oil converter 4B and the air chamber 10A of the air-oil converter 4A, and the compressed air is supplied to each displacement member. 7B and 7A are displaced to the position shown in the figure in the opposite direction to that described above. Then, the pressurized hydraulic oil in the oil chamber 8B of the air-oil converter 4B is supplied to the forward movement chamber 3B of the hydraulic actuator 1, and the hydraulic oil in the forward movement chamber 3A of the hydraulic actuator 1 is supplied to the oil chamber 8B of the air-oil converter 4A. It flows into the chamber 8A, and the piston 2 is moved back to the right in the figure.

In this operation, when a load is applied to the piston 2 during the backward movement of the hydraulic actuator 1, the pressure in the backward movement chamber 3B becomes higher than the pressure in the forward movement chamber 3A due to the magnitude of the load and the difference in pressure receiving areas on both sides of the piston 2. The hydraulic fluid in the forward movement chamber 3B leaks from the sliding portion of the piston 2 into the forward movement chamber 3A due to the pressure difference between the chambers on both sides of the piston 2. The amount of oil in the oil chamber 8A of the air-oil converter 4A increases due to this hydraulic oil leakage, and when the displacement member 7A is displaced to the other side, the oil chamber 8A is communicated with the annular groove 11A near the displacement end. Therefore, the increased amount of hydraulic oil flows through the flow path 13A and is discharged to the oil storage tank 12 to be corrected. In addition, the amount of oil in the oil chamber 8B of the air-oil converter 4B, where the hydraulic oil decreases due to the aforementioned oil leakage, is such that when the displacement member 7B is displaced toward the other side, compressed air is supplied to the air chamber 10B from the displacement member 7B. Due to the forced displacement due to the acting force of Near the displacement end, the oil chamber 8B is communicated with the annular groove 11B, and the hydraulic oil in the oil storage tank 12 flows therein for correction.

Furthermore, when a load is applied to the piston 2 during the forward movement of the hydraulic actuator 1, and the hydraulic fluid increases or decreases in the forward movement chamber 3A and the backward movement chamber 3B in the opposite manner to that described above, the two air-oil converters 4A and 4B do the same. Its increase or decrease is corrected by action.

As a result, the air-oil converters 4A and 4B are operated to discharge the increased amount of hydraulic oil in the oil chambers 8A and 8B to the oil storage tank 12, and the decreased amount of hydraulic oil in the oil chambers 8B and 8A flows from the oil storage tank 12. Because it is possible, air-oil converter 4A, 4
The amount of oil in the oil chamber can be adjusted without stopping the operation of B, and the operating efficiency of the device can be improved. In addition, the oil chambers 8A and 8B of the air-oil converters 4A and 4B on the forward and reverse sides are connected to the annular grooves 11A and 11B through the flow passages 11A and 11B.
A single oil storage tank 12 shared through A and 13B
Because it is connected to
If the oil chamber of the air-oil converter on the forward side and the oil chamber of the air-oil converter on the backward side are provided with separate oil storage tanks that communicate with each other, the forward movement chamber and the backward movement can be connected by the reciprocating movement of the hydraulic actuator. The hydraulic oil in each oil storage tank increases or decreases significantly due to leakage between the forward and backward movement chambers caused by the pressure difference between the chambers. Each oil storage tank must be provided in a large size to prevent it from overflowing or disappearing, but compared to this, the operation inside the oil storage tank 12 due to leakage between the forward movement chamber 3A and the backward movement chamber 3B of the hydraulic actuator 1 is difficult. The increase and decrease of oil can be minimized, and oil storage tank 1
Reference numeral 2 is a small type that stores a small amount of hydraulic oil, which allows the hydraulic actuator 1 to perform good reciprocating motion over a long period of time, and allows the device to be miniaturized.
The on-off valves 15A and 15B are closed during operation of the device and opened when air accumulated in the oil chambers 8A and 8B is vented.

〔Effect of the invention〕

In this way, the present invention displaces the displacement member slidably housed inside to one side to discharge the hydraulic oil in the oil chamber into the forward movement chamber of the hydraulic actuator, and at the same time displaces the displacement member to the other side. There is an air-oil converter on the forward side that allows hydraulic oil from the forward movement chamber of the hydraulic actuator to flow into the oil chamber, and a displacement member that is slidably housed inside is displaced to one side to drain the hydraulic oil in the oil chamber. and an air-oil converter on the reciprocating side that discharges hydraulic oil into the reciprocating chamber of the hydraulic actuator and displaces the displacement member to the other side so that hydraulic oil from the reciprocating chamber of the hydraulic actuator flows into the oil chamber. The displacement member of the air-oil converter on the forward-moving side is displaced to one side, the displacement member of the air-oil converter on the backward-moving side is displaced to the other side, or the displacement member of the air-oil-oil converter on the forward-moving side is displaced to the other side. Compressed air is freely applied to the displacement member of each pneumatic-hydraulic converter so that the displacement member of the pneumatic-hydraulic converter on the forward-moving side and the backward-moving side is displaced to one side. The oil chambers are connected to a common single oil storage tank through each passage provided with a check valve to allow the inflow of hydraulic oil from the oil storage tank, and each air-oil converter has a displacement member. By providing a flow path that opens when the displacement member is displaced near the displacement end on the other side and communicates between the oil chamber and the oil storage tank, the oil chamber is communicated with the oil storage tank each time the displacement member is displaced to the other side. The amount of oil in the oil chamber can be adjusted without stopping the operation of the oil converter, and the operating efficiency of the device can be improved.

In addition, the oil chamber of the air-oil converter on the forward side and the oil chamber of the air-oil converter on the backward side are made into a common unit through a flow path that opens when the displacement member is displaced near the displacement end on the other side. Because it communicates with the oil storage tank of the The oil chamber of the converter and the oil chamber of the air-oil converter on the double-acting side are provided with separate oil storage tanks that communicate with each other.
The hydraulic oil in each oil storage tank increases or decreases significantly due to leakage between the forward and backward chambers caused by the pressure difference between the forward and backward chambers during the reciprocating motion of the hydraulic actuator.
In order to prevent the hydraulic oil stored in each oil storage tank from overflowing or running out during the reciprocating movement of the hydraulic actuator, each oil storage tank must be provided in a large size. Increases and decreases in the hydraulic oil in the oil storage tank due to leaks between chambers can be minimized, and the oil storage tank is small enough to store a small amount of hydraulic oil, allowing the hydraulic actuator to maintain good reciprocating motion over a long period of time. This has the effect of making the device smaller.

[Brief explanation of drawings]

The drawing is a partially cross-sectional circuit diagram of an embodiment of the present invention. 1... Hydraulic actuator, 3A... Forward movement chamber,
3B... Double action chamber, 4A, 4B... Air-oil converter, 7
A, 7B...Displacement member, 8A, 8B...Oil chamber, 1
2...Oil storage tank, 13A, 13B, 14A, 14B
...Flow path, 16A, 16B...Check valve.

Claims (1)

[Claims] 1 Displace the displacement member slidably housed inside to one side to discharge the hydraulic oil in the oil chamber to the forward movement chamber of the hydraulic actuator, and also displace the displacement member to the other side to discharge the hydraulic oil from the oil chamber to the forward movement chamber of the hydraulic actuator. The air-oil converter on the forward side flows hydraulic oil from the oil chamber into the oil chamber, and the displacement member slidably housed inside is displaced to one side to transfer the hydraulic oil from the oil chamber to the return chamber of the hydraulic actuator. and a reciprocating-side pneumatic-oil converter that displaces the displacement member to the other side and causes hydraulic oil from the reciprocating chamber of the hydraulic actuator to flow into the oil chamber. By displacing the displacement member to one side, the displacement member of the pneumatic-hydraulic converter on the backward-moving side is displaced to the other side, or by displacing the displacement member of the pneumatic-hydraulic converter on the forward-moving side to the other side, Compressed air is provided to freely act on the displacement member of each air-oil converter so that the displacement member of the oil converter is displaced to one side, and the oil chambers of the air-oil converters on the forward and backward sides are checked. Each air-oil converter displaces the displacement member to the other side by communicating with a common single oil storage tank through each flow path provided with a valve to allow the inflow of hydraulic oil from the oil storage tank. A pneumatic oil control device comprising a flow path that opens when a displacement member is displaced near the other displacement end of the displacement member so as to communicate the oil chamber with the oil storage tank, thereby communicating the oil chamber and the oil storage tank.