JPH0410410Y2 - - Google Patents

Description

[Detailed Description of the Invention] [Industrial Application Field] The present invention relates to fluid pressure operated equipment, and in particular to a technique that is effective when applied to cylinder devices and the like used in clean work spaces.

[Conventional technology]

For example, in fields that require a high degree of cleanliness in the work space, such as the manufacturing of semiconductor devices and medical equipment, clean rooms are generally constructed to maintain the amount of dust inside to below a predetermined value. , Predetermined work is performed inside this clean room.

In such a case, in a cylinder device used in a clean room, it is necessary to take measures against contamination of the working space by foreign substances such as oil mist and metal powder that are scattered outside from the insertion part of the piston rod into the cylinder body.

For this reason, for example, a ventilator tube is interposed in the working fluid supply/discharge path that supplies and discharges compressed air, etc. to and from the cylinder body, and the throat of this ventilator tube is communicated with the insertion part of the piston rod into the cylinder body. When the exhaust flow from the main body passes through the ventilate tube, the negative pressure generated in the throat section sucks the insertion part of the piston rod, thereby removing foreign substances such as oil mist and metal powder generated in the insertion part. It is possible to prevent contamination of the work space by trapping it.

[Problem that the invention attempts to solve]

However, as described above, in a structure in which a ventilator pipe is simply interposed in the working fluid supply/discharge path, for example, when the operating speed of the piston rod is relatively fast and the exhaust flow rate becomes large, the flow rate of the piping connected to the working fluid supply/discharge path becomes As the flow resistance increases, the exhaust flow rate cannot be effectively converted into a differential pressure between the exhaust flow before and after the ventilate tube, and the efficiency of generating negative pressure from the exhaust flow decreases, making it difficult to effectively remove foreign objects at the insertion part of the piston rod. There are problems such as not being able to capture images.

An object of the present invention is to provide a fluid pressure-operated device that can prevent foreign matter from scattering from the insertion portion of a drive member and reliably prevent contamination of a working space.

[Means for solving problems]

The present invention provides a fluid pressure system in which a ventilary pipe is interposed in a working fluid supply/discharge path connected to a fluid pressure operating device, and the throat of the ventilary pipe is communicated with an insertion portion of a drive member in the fluid pressure operating device. The operating device is equipped with a working fluid storage means on the inlet side of the exhaust flow from the fluid pressure operating device to the ventilate pipe in the working fluid supply/discharge path, and a quick exhaust valve on the outlet side.

[Effect]

According to the above-mentioned means, the pressure of the working fluid accumulated in the working fluid storage means is added to the exhaust pressure of the working fluid that drives the fluid pressure operated device, and the outlet of the ventilary pipe is operated by the quick exhaust valve. Since the discharge resistance of the exhaust flow on the sides is reduced, the pressure difference between the exhaust flow before and after the ventilee pipe increases, and the flow velocity of the exhaust flow passing through the ventilee pipe increases, which effectively hits the throat of the ventilee pipe. By generating negative pressure, it is possible to reliably capture foreign matter in the insertion portion of the drive member, and it is possible to reliably prevent contamination of the work space.

[Embodiment] Fig. 1 is a partial sectional view showing an enlarged main part of a fluid pressure operated device which is an embodiment of the present invention.
The figure is a partially cutaway side view of the fluid pressure operating device, FIG. 3 is a fluid circuit diagram thereof, and FIG. 4 is a diagram showing its performance in comparison with a conventional case.

In this embodiment, the fluid pressure operating device is configured as a cylinder device that uses compressed air as a working fluid.

That is, both ends of the cylinder body 1 are closed by an end cover 2 and a rod cover 3, and a fluid chamber L and a piston 4 are provided inside the cylinder body 1 so as to be slidable in the axial direction. A fluid chamber R is formed respectively.

A piston rod 5 (driving member) whose one end extends through the rod cover 3 and projects to the outside is locked to the piston 4.

The end cover 2 and the rod cover 3 are formed with a working fluid supply/discharge passage 6 and a working fluid supply/discharge passage 7 that communicate with the fluid chambers L and R, respectively.

The working fluid supply/discharge path 6 and the working fluid supply/discharge path 7
are the working fluid supply pipe 6a and the working fluid supply pipe 7
A is connected to an external air pressure source A and a directional control valve B, and compressed air is alternately supplied and discharged from the air pressure source A to the fluid chambers R and L by operating the directional control valve B as appropriate. By doing so, a thrust force is generated that causes the piston rod 5 to reciprocate in the axial direction.

Working fluid supply/discharge path 6 provided in the end cover 2
and the working fluid supply pipe 6a, the working fluid supply/discharge passage 7 provided in the rod cover 3, and the working fluid supply pipe 7a.
A speed control valve 8 is interposed at the connection portion with each.

This speed control valve 8 will not be described in detail, but from the outside, the fluid chamber R or L inside the cylinder body 1 is
a check valve 8a that allows the working fluid to pass only in the direction;
It consists of a flow rate adjustment valve 8c whose opening degree can be varied by appropriately rotating an adjustment knob 8b.
In FIG. 1, the operating speed of the piston rod 5 is adjusted by controlling the flow rate of the exhaust flow E in the fluid chamber R.

A ventilator pipe 9 is interposed between the speed control valve 8 and the working fluid supply pipe 7a.
Dust collection adapter 11 attached to surround the insertion part of
It is connected to the inside of the.

When the exhaust flow E passes through the ventilate pipe 9, it is generated at the throat portion 9a.

A check valve mechanism 12 is provided at the connection portion of the suction pipe 10 to the ventilate pipe 9, and gas can flow only in the direction from the dust collecting adapter 11 to the ventilic pipe 9.

That is, this check valve mechanism 12
A diameter-reducing valve seat 12a provided on the side of the valve, and a plurality of through holes 12b provided on the side of the ventilate tube 9.
The nozzle valve seat 12c is formed with a diameter reducing valve seat 12.
a and a valve body 12d provided in a floating state between the nozzle valve seat 12c and the valve body 12d.
is in close contact with the diameter-reducing valve seat 12a, thereby preventing gas from flowing from the ventilary tube 9 toward the dust collection adapter 11, and conversely, the ventilary tube 9
When the side becomes negative pressure, the valve body 12d becomes the nozzle valve seat 12.
When the valve body 12d is brought into close contact with the valve body 12d, gas is sucked from the dust collection adapter 11 side toward the ventilate tube 9 through the plurality of through holes 12b from the periphery of the valve body 12d.

In this case, the working fluid supply/discharge path 7 between the speed control valve 8 and the ventilate pipe 9 includes:
An accumulation tank 13 (working fluid accumulation means) having a predetermined volume is connected to the inlet side of the exhaust flow E in the ventilate pipe 9, and the air pressure source A is connected to the cylinder through the working fluid supply pipe 7a and the working fluid supply/discharge path 7. A part of the compressed air supplied to the fluid chamber R of the main body 1 is accumulated, and during the exhaust operation in the fluid chamber R, the compressed air accumulated inside this accumulation tank 13 is added to the exhaust flow E. It is structured so that it passes through a ventilate tube 9.

Furthermore, in the working fluid supply/discharge path 7, the exhaust flow E
A rapid exhaust valve 14 is provided on the outlet side of the ventilate tube 9 in the direction in which the gas passes through.

The quick exhaust valve 14 has an inlet IN connected to the working fluid supply pipe 7a, an outlet OUT connected to the outlet side of the ventilate pipe 9, and an exhaust pipe 1.
Exhaust port connected to the outside of the workspace via 4a
EXH, and a valve seat 14b at the inner end of the inlet IN and a valve seat 14b at the inner end of the exhaust port EXH.
A floating valve body 14d is interposed between the valve body 4b and the valve body 4b.

When a working fluid such as compressed air is applied to the inlet IN from the working fluid supply pipe 7a, the valve seat 14b is brought into close contact with the valve seat 14c on the exhaust port EXH side, and the inlet IN and outlet OUT are communicated with each other. state, compressed air etc. quickly flows into the cylinder body 1 from the working fluid supply pipe 7a via the working fluid supply/discharge path 7, and conversely, when the exhaust flow E flows into the outlet OUT side. In this case, the valve body 14d is connected to the inlet IN.
The outlet OUT and exhaust port are in close contact with the valve seat 14b on the side.
EXH is in communication, and the exhaust flow E is the exhaust port.
The structure is such that the fluid is guided in the direction of EXH and is quickly discharged to the outside without being subjected to large flow path resistance, such as when the fluid is discharged by flowing backward through the working fluid supply pipe 7a.

As shown in FIG. 2, a similar structure is provided at the connection between the working fluid supply/discharge path 6 and the working fluid supply pipe 6a on the side of the end cover 2, but the explanation of the structure is as follows. Omitted to avoid duplication.

The operation of this embodiment will be explained below.

First, by appropriately controlling the directional control valve B to connect the air pressure source A to the working fluid supply pipe 7a and opening the working fluid supply pipe 6a, compressed air at a predetermined pressure is supplied from the working fluid supply pipe 7a. Acted on the inlet IN of the quick exhaust valve 14, the valve body 14d becomes the exhaust port.
The inlet IN is in close contact with the valve seat 14c of EXH, and the outlet OUT connected to the working fluid supply/discharge path 7 is in communication, and the working fluid such as compressed air passes through the working fluid supply/discharge path 7 to the fluid chamber. The piston rod 5 is displaced in the direction in which it is drawn into the cylinder body 1.

At this time, the check valve mechanism 12 interposed between the ventilator tube 9 and the suction tube 10 is closed, preventing compressed air from acting on the dust collection adapter 11 through the suction tube 10, and preventing the accumulation of air. A predetermined amount of compressed air is stored in the tank 13 .

Conversely, when the directional control valve B is activated, the working fluid supply pipe 6a on the end cover 2 side is connected to the air pressure source A, and the working fluid supply pipe 7a is opened.
Compressed air is supplied from the working fluid supply pipe 6a to the fluid chamber L via the quick exhaust valve 14 and the working fluid supply/discharge path 6, and the piston rod 5 is displaced in the direction of protruding from the cylinder body 1. The compressed air inside the side fluid chamber R is supplied to the working fluid supply/discharge path 7, the speed control valve 8, and the ventilate pipe 9.
The exhaust flow E passing through reaches the outlet OUT of the quick exhaust valve 14, and in the quick exhaust valve 14,
The valve body 14d is in close contact with the valve seat 14b on the inlet IN side, and the outlet OUT and the exhaust port EXH are in communication, and the exhaust flow E acting on the outlet OUT is not subjected to large flow resistance, etc., and is connected to the exhaust port EXH. The gas is then quickly discharged to a predetermined location other than the work space via the exhaust pipe 14a.

At this time, in the ventilate pipe 9 provided in the working fluid supply/discharge path 7, the exhaust flow E from the fluid chamber R is
The compressed air stored in the storage tank 13 passes through, and the passage resistance of the exhaust flow E at the outlet side of the ventilate pipe 9 is reduced by the action of the quick exhaust valve 14 provided at the outlet side of the ventilly pipe 9. is reduced, the pressure difference in the exhaust flow E before and after the ventilee tube 9 increases, and the flow velocity of the exhaust flow E passing through the throat portion 9a of the ventilee tube 9 increases. A relatively large negative pressure is generated, and the check valve mechanism 12 is opened by this negative pressure, and the suction pipe 1 is opened.
The inside of the dust collecting adapter 11 is sucked through the dust collecting adapter 11.

Foreign matter such as oil mist and metal powder generated at the insertion portion of the piston rod 5 into the rod cover 3, which is surrounded by the dust collection adapter 11, is captured without scattering into the work space, and the captured foreign matter is Together with the exhaust flow E, it is reliably removed to a predetermined location other than the work space such as a clean room.

The above series of operations is performed in the same way on the end cover 2 side, and since the compressed air supply and discharge operations in the working fluid supply and discharge passages 6 and 7 are opposite to each other, the dust collection adapter The inside of the tube 11 is constantly sucked during operation by the negative pressure in the throat 9a of the ventilate tube 9 provided on each side of the end cover 2 and rod cover 3.

Here, the pressure P ₁ of the exhaust flow E at the inlet of the ventilate tube 9 according to the displacement S of the piston 4,
The relationship between this example and the negative pressure _P2 obtained in the throat portion 9a due to the passage of this exhaust flow E is as follows.
3 and a conventional case in which the quick exhaust valve 14 and the like are not provided are shown in comparison.

As shown in the figure, in the conventional case where the storage tank 13 and the quick exhaust valve 14 are not provided,
The pressure of the exhaust flow E at the inlet of the ventilate tube 9
P ₁ decreases rapidly at the beginning of the exhaust operation, and the flow rate of the exhaust flow E passing through the ventilate tube 9 decreases, so that the negative pressure P ₂ in the throat 9a saturates at a relatively small value and , the generation of negative pressure P ₂ tends to increase after the start of displacement of the piston 4.

However, when the storage tank 13 and the rapid exhaust valve 14 are provided as in this embodiment, the compressed air stored in the storage tank 13 is added to the exhaust flow E on the inlet side of the ventilate pipe 9. At the same time, the passage resistance of the exhaust flow E on the downstream side of the ventilate pipe 9 is reduced by the action of the rapid exhaust valve 14, so that the head difference between the pressure _P1 of the exhaust flow E at the inlet of the ventilate pipe 9 and the outlet side is large. Therefore, the flow velocity of the exhaust flow E passing through the ventilate pipe 9 can be increased.

As a result, the value of the negative pressure _P2 generated in the throat portion 9a at the beginning of the exhaust operation increases rapidly even before the displacement of the piston 4 starts, and
Since the displacement is maintained at a relatively large value over almost the entire length, the dust collection adapter 11 can more effectively capture foreign substances such as oil mist and metal powder, and can be used in clean rooms where the cylinder device is installed, etc. Contamination of the working space can be reliably prevented.

It goes without saying that the present invention is not limited to the above-mentioned embodiments, and can be modified in various ways without departing from the spirit thereof.

For example, the working fluid storage means is not limited to connecting a container such as the storage tank 13 to the working fluid supply/drainage path, but may also have a structure in which the diameter of a part of the working fluid supply/drainage path is expanded to secure the storage volume. You can.

Further, the fluid pressure operated device is not limited to a cylinder device, but may be any other device such as a rotary actuator.

[Effect of idea]

(1) Fluid pressure operation in which a ventilator tube is interposed in the working fluid supply/discharge path connected to the fluid pressure actuator, and the throat of the ventilee tube is communicated with the insertion part of the drive member in the fluid pressure actuator. The device is provided with a working fluid storage means in the working fluid supply/discharge path on the inlet side of the exhaust flow from the fluid pressure operated device to the ventilate pipe,
Since the structure is equipped with a quick exhaust valve on the outlet side, the working fluid accumulated in the working fluid storage means is added to the exhaust pressure of the working fluid that drives the fluid pressure operated equipment, and the function of the quick exhaust valve is As a result, the discharge resistance of the exhaust flow on the outlet side of the ventilee pipe is reduced, so that it is possible to increase the pressure difference between the exhaust flow before and after the ventilee pipe, thereby increasing the flow velocity of the exhaust flow passing through the ventilee pipe. By effectively generating negative pressure in the throat of the ventilate tube, it is possible to efficiently capture foreign matter in the insertion portion of the drive member.
It becomes possible to reliably prevent contamination of the work space.

(2) As a result of (1) above, the performance of fluid pressure operated equipment is improved.

[Brief explanation of drawings]

FIG. 1 is a partially sectional view showing an enlarged main part of a fluid pressure-operated device which is an embodiment of the present invention, and FIG. 2 is a side view showing a part of the fluid pressure-operated device broken away.
FIG. 3 is a fluid circuit diagram, and FIG. 4 is a diagram showing performance in comparison with a conventional case. 1... Cylinder body, 2... End cover, 3
... Rod cover, 4 ... Piston, 5 ... Piston rod (driving member), 6, 7 ... Working fluid supply and discharge passage, 6a, 7a ... Working fluid supply pipe, 8 ... Speed control valve, 8a ... Reverse Stop valve, 8b...adjustment knob,
8c...Flow rate adjustment valve, 9...Venture pipe, 9
a... Throat, 10... Suction pipe, 11... Dust collection adapter, 12... Check valve mechanism, 12a... Diameter reduction valve seat, 12b... Through hole, 12c... Nozzle valve seat, 1
2d... Valve body, 13... Storage tank (working fluid storage means), 14... Rapid exhaust valve, 14a... Exhaust pipe, 14b... Valve seat, 14c... Valve seat, 14d...
...Valve body, IN...Inlet, OUT...Outlet, EXH...
...Exhaust port, E...Exhaust flow, A...Air pressure source, B...
... Directional control valve, R, L ... Fluid chamber, S ... Displacement of the piston, P ₁ ... Pressure of the exhaust flow at the inlet of the ventilate tube, P ₂ ... Negative pressure at the throat.

Claims (1)

[Claims for Utility Model Registration] (1) A ventilator tube is interposed in a working fluid supply/discharge path connected to a fluid pressure operated device, and the throat of the ventilee tube is inserted into the passage of a driving member in the fluid pressure operated device. A fluid pressure operated device is provided with a working fluid accumulating means on the inlet side of the exhaust flow from the fluid pressure operated device to the venturi pipe in the working fluid supply/discharge path,
A fluid pressure operated device characterized by having a quick exhaust valve on the outlet side. (2) The fluid pressure operating device according to claim 1, wherein the fluid pressure operating device is a cylinder device using compressed air as a working fluid, and the driving member is a piston rod. (3) A utility model according to claim 1, characterized in that a speed control valve is interposed in the working fluid supply/discharge path between the working fluid accumulating means and the fluid pressure operated device. Fluid pressure operated equipment. (4) A check valve mechanism is interposed between the throat of the ventilate tube and the insertion portion of the driving member to allow fluid to pass only in the direction from the insertion portion to the throat. A fluid pressure operated device according to claim 1 of the utility model registration claim.