JP3411131B2 - Keep valve - Google Patents

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a keep valve capable of maintaining the pressure of fluid in a cylinder even after the pressure fluid supply device is removed and fixing the position of a piston inserted in the cylinder.

[0002]

2. Description of the Related Art In a conventional valve, a device for holding the pressure of fluid in a cylinder, fixing the position of a piston inserted in the cylinder, and moving the piston when necessary is known as a pressure fluid supply device (for example, a pressure fluid supply device). Some of them are realized by constantly connecting a fluid supply device, a compressor, etc.) to a cylinder.

However, the pressure fluid supply device of the detachable type is used. When the pressure fluid is supplied to the cylinder only when necessary, the residual fluid in the cylinder is discharged and the pressure fluid supply device is automatically disconnected. There was nothing that could close the valve and keep the pressure in the cylinder.

[0004]

In a device of the type in which piping is always connected, the pressure fluid supply device must always be arranged together with the cylinder, and when it is necessary to change the direction of the cylinder or move it. It is inconvenient.
In addition, there are cases where it is difficult to keep the pipes connected at all times due to the limited work space and the arrangement with another device.

[0005]

According to a first aspect of the present invention, a valve body 3, 3a is provided at one end and a large-diameter piston 6 is provided at the other end.
First and second cylinders 20 and 20a of the same shape, into which rods 5 and 5a provided with 6a are inserted, are arranged adjacent to each other, and the first and second cylinders 20 and 20a are branched near the center to the outside of the cylinder. There are passages 2 and 2a,
In addition, from the vicinity of the center of the first cylinder 20 to the second cylinder 2
There is provided a first bypass passage 18 communicating from the large diameter piston 6a of the large inner diameter portion 10a into which the large diameter piston 6a of 0a is inserted to the end side of the second cylinder 20a.
The large diameter piston 6 of the first cylinder 20 from near the center of 0a
A second bypass passage 18a communicating with the large-diameter piston 6 of the large-diameter portion 10 into which the end portion of the cylinder 20 is inserted is provided, and the branch passage 2 and the first bypass passage 18 and the Ouchi
Airtightness is maintained between the diameter portion 10 and the branch passage.
The passage 2a, the second bypass passage 18a, the large inner diameter portion 10a,
The airtightness is maintained also during this period, and springs 8 and 8a for biasing the large-diameter pistons 6 and 6a to the side opposite to the branch passages 2 and 2a are contracted in the cylinders 20 and 20a . 8a
And a rod integral with the large-diameter pistons 6 and 6a.
5, 5a move in the first and second cylinders 20, 20a
The valve in the first and second cylinders 20 and 20a.
Further movement of the rods 5, 5a in contact with the bodies 3, 3a
Valve seats 27 and 27a for preventing the
When the valve bodies 3, 3a are in contact with 7, 27a, the valve body
First and second cylinders 20, 2 accommodating 3, 3a
0a, the inner diameter portions 11 and 11a, and the branch passages 2 and 2
Airtight between a and the first and second bypass passages 18 and 18a
The keep valve is characterized in that

In the second invention, a pair of first rigid pipes 54, 54 are provided in boxes 55, 55a having spaces 34, 34a therein.
a, the second rigid pipes 58, 58a are kept airtight, respectively, penetrate from the outside of the boxes 55, 55a to the spaces 34, 34a, and face each other in the spaces 34, 34a, and are arranged in a horizontal straight line, The first rigid pipes 54, 54a and the second rigid pipe 5 in the spaces 34, 34a.
The outer circumferences of the two facing openings of 8, 58a are covered with the both ends of one elastic pipe 28, 28a, respectively, and connected.
The boxes 55, 55a of the first rigid pipes 54, 54a
The outer end communicates with the outside, and the elastic pipe 28,
The upper projections 45, 45a are provided on the upper inner wall surfaces of the boxes 55, 55a just above 28a.
5a and the lower portion of the elastic pipes 28, 28a, a lower protrusion 42,
42a is provided, and the column 2 is provided on the lower protrusions 42, 42a.
9, 29a are provided, holes 37, 37a are provided in the boxes 55, 55a so as to communicate with the spaces 34, 34a and the columns 29, 29a can slide, and are concentric with the holes 37, 37a. Communicating, holes 47, 47 having a diameter larger than holes 37, 37a
a is provided with large-diameter pistons 48 and 48a that are airtight and slidable, and the large-diameter pistons 48 and 48a are in contact with the support columns 29 and 29a.
0, 70a, the space 34 of the first valve 70, the second
The rigid pipe 58 and the bottom of the hole 47a of the second valve 70a have first communication passages 35, 39, second communication passages 36, 4 respectively.
0, the third communication passage 38a communicates with the first chamber 41, and the first chamber 41 communicates with the one end of the third cylinder 50 in which the piston 53 is inserted by the seventh communication passage 46, and the second valve 70a. Of the space 34a, the second rigid pipe 58a, and the bottom of the hole 47 of the first valve 70, respectively.
a, 39a, fifth communication passages 36a, 40a, sixth communication passage 3
8 is a keep valve which communicates with the second chamber 41a by means of 8, and the second chamber 41a communicates with the other end of the third cylinder 50 by means of an eighth communication passage 46a.

[0007]

DETAILED DESCRIPTION OF THE INVENTION

(Embodiment of the First Invention) FIG. 1 is a partially longitudinal sectional front view of a keep valve 100 to which the first invention is applied. As shown in FIG. 1, the keep valve 100 has a first block 30.
The cylinder 20 and the second cylinder 20a are formed symmetrically. A lid 31 and a lid 32 are fixed to the block 30 with screws 21 to 26, respectively, as shown in FIG.

Since the first cylinder 20 and the second cylinder 20a are symmetrical, the structure of the first cylinder 20 of FIG. 1 will be described below. The structure of the second cylinder 20a is to be read by adding a to the reference numeral of the member of the first cylinder 20.

A large inner diameter portion 10, a small inner diameter portion 12 and a middle inner diameter portion 11 are concentrically connected in this order to the block 30 to form a cylinder 20. Branch passage 2 in small inner diameter portion 12
Is provided, and the branch passage 2 communicates with the outside.

A large-diameter piston 6 is slidably inserted into the large-inner diameter portion 10 by an O-ring 16 while keeping airtightness. A rod 5 is integrally fixed to the large-diameter piston 6, and the other end of the rod 5 forms a valve body 3. The small inner diameter portion 12 is provided with a bypass passage 18 communicating with the large inner diameter portion 10a between the lid 31 and the large diameter piston 6a of the cylinder 20a. A valve seat 27 corresponding to the valve body 3 is provided in the inner diameter portion 11. The valve body 3 is provided with a packing 4, and the packing 4 contacts the valve seat 27 to keep airtight.

A lid 31 is fixed to the large inner diameter portion 10 side of the block 30 with screws 21, 22 and 23, and an O-ring 19 keeps airtightness. A lid 32 is fixed to the inner diameter portion 11 side of the block 30 with screws 24, 25, and 26, and an O-ring 15 keeps airtightness. Screw 2
1-26 only show some of the screws that fix the lids 31 and 32, and a plurality of screws are used in the direction perpendicular to the paper surface of FIG.

The lid 32 has a hole 33 concentric with the inner diameter portion 11.
Is provided. A pipe 51 shown in FIG. 10 is airtightly connected to the hole 33, and the other end of the pipe 51 is airtightly connected to one end of the third cylinder 50 shown in FIG. 10.
A pipe 52 is airtightly connected to the hole 33a, and the other end of the pipe 52 is airtightly connected to the other end of the third cylinder 50 shown in FIG.

A filter 17 is provided at the opening of the branch passage 2 to prevent foreign matter from entering the cylinder 20. A seat 170 having a working fluid inlet / outlet port 63 is fixed to the branch passage 2 outside the filter 17 with a screw. When the pressure fluid supply device 150 is pressed against the working fluid inlet / outlet 63, the O-ring 171 keeps airtight so that the supplied pressure fluid does not leak.

The large inner diameter portion 10 is provided with a step 13 on the side communicating with the small inner diameter portion 12, and in the vicinity of the step 13, there is provided a small hole 14 serving as a device for venting air to the outside. .

The large inner diameter portion 10 and the small inner diameter portion 12 communicate with each other by forming a step 130, and the coil spring 8 is contracted between the step 130 and the large diameter piston 6. The large-diameter piston 6 and the rod 5 are integrally urged upward by the pressing force of the coil spring 8 as viewed in FIG. 1, and the packing 4 provided on the valve body 3 is in airtight contact with the valve seat 27. .

When the large-diameter piston 6 slides in the large-inner diameter portion 10 while keeping airtightness and moves in the direction in which the coil spring 8 is contracted, it abuts against the step 13 formed in the large-inner diameter portion 10 and stops.

The pressure receiving area S1 (not shown) for the pressure fluid in the portion opened and closed by the packing 4 is set smaller than the pressure receiving area S2 (not shown) for the pressure fluid of the large-diameter piston 6.

FIG. 10 shows the keep valve 100 connected to the third cylinder 50. The branch passage 2 is connected to the pipe 51 from the working fluid inlet / outlet 63, and the branch passage 2a is connected to both ends of the third cylinder 50 from the working fluid inlet / outlet 63a via the pipe 52. A piston 53 is inserted in the third cylinder 50. Further, FIG. 10 shows a state in which the tip nozzle portion of the pressure fluid supply device 150 for supplying pressure fluid to the keep valve 100 is mounted on the working fluid inlet / outlet 63 side. The pressure fluid supply device 150 is detachable, and can also be attached to the working fluid inlet / outlet port 63a side.

Next, the operation will be described. Now, it is assumed that the piston 53 inserted in the third cylinder 50 in FIG. 10 is located at the left end of the third cylinder 50. In order to move the piston 53 to the right from this state, as shown in FIG.
From the working fluid inlet / outlet port 63 of FIG.
A pressure fluid is supplied by 50. Pressure fluid supply device 15
0 is, for example, an air gun driven by a compressor, or Japanese Patent Application No. 6-260, which supplies pressure fluid with one touch.
The fluid ejector of No. 106 is used.

The pressure fluid acts on the packing 4 and the large-diameter piston 6a in FIG. 1, but the pressure-receiving area S2 of the large-diameter piston 6a.
2 is larger than the pressure receiving area S1 of the packing 4, the large-diameter piston 6a is first moved against the elastic force of the coil spring 8a until it comes into contact with the step 13a, and the state shown in FIG. 2 is obtained.

Since the large-diameter piston 6a moves until it comes into contact with the step 13a, the rod 5a integrated with the large-diameter piston 6a, the valve body 3a and the packing 4a also move and the packing 4
The valve seat 27a closed by a is opened, and
The fluid remaining in the right chamber 50b of the cylinder 50 is
From the working fluid inlet / outlet 6 via the cylinder 20a (FIG. 1)
It is discharged from the keep valve 100 from 3a.

When the large-diameter piston 6a comes into contact with the step 13a, the pressure fluid supplied from the pressure-fluid supply device 150 in turn causes the rod 5 and the large-diameter piston 6 in FIG. 2 to resist the elastic force of the coil spring 8. The packing 4 to move the valve seat 2
7 and the state shown in FIG.

When the valve element 3 separates from the valve seat 27 as shown in FIG. 3, the pressure fluid flows from the working fluid inlet / outlet 63 through the branch passage 2 and the cylinder 20 to the pipe 51 of FIG. 10 to the left chamber of the third cylinder 50. The pressure fluid is supplied to 50a, and the piston 53 moves to the right. When the piston 53 moves to a preset position, the pressure fluid supply device 150 is removed from the working fluid inlet / outlet 63, and the supply of the pressure fluid is stopped. When the supply of the pressure fluid is stopped, the keep valve 100 returns to the initial state in which the valve seats 27 and 27a are closed by the valve elements 3 and 3a as shown in FIG.

Here, the pressure fluid remaining in the third cylinder 50 is discharged from the pipe 52 before the pressure fluid is supplied to the third cylinder 50 from the pipe 51 of FIG. 10 because the movement of the piston 53 is smooth. In order to reduce the area difference between the pressure receiving area S2 of the large diameter piston 6a and the pressure receiving area S1 of the packing 4, the packing 4 integrated with the large diameter piston 6 before the large diameter piston 6a contacts the step 13a. The (valve body 3) is opened. Therefore, by adjusting the area difference, the piston 53 can be moved abruptly and quickly or slowly.

In order to move the piston 53 quickly, it is sufficient to reduce the area difference between the pressure receiving area S2 of the large-diameter piston 6 (6a) and the pressure receiving area S1 of the packing 4 (4a) in FIG. If you want to get a coil spring 8
The pressure receiving area S1 may be set to be larger than the pressure receiving area S2 in consideration of the balance between the elastic force and the pressure of the fluid to be supplied.

In order to move the piston 53 of FIG. 10 to the left in the opposite direction, pressure fluid is supplied from the working fluid inlet / outlet port 63a. The operation of the keep valve 100 in this case is the reverse of the case where the pressure fluid is supplied from the working fluid inlet / outlet port 63.

(Embodiment of the Second Invention) FIG. 4 is a partially longitudinal sectional front view showing the structure of a keep valve 200 to which the second invention is applied. The keep valve 200 is composed of a first valve 70 and a second valve 70a. The first valve 70 is a plastic block 55, 56 fixed with bolts and nuts (not shown), steel lids 57, 62, and a stainless steel pipe with a flange. 54, 58, an elastic pipe 28 (a pipe made of a soft material such as a silicon tube), a lower protrusion 42, a large-diameter piston 48, etc., and a second valve 70a.
As shown in FIG. 4, the structure is symmetrical to the first valve 70, and the member number of the first valve 70 is added with a to replace it.

As shown in FIG. 8 which is a sectional view taken along the line VIII-VIII of FIG. 4 and FIG. 9 which is a sectional view taken along the line IX-IX of FIG.
A lid 59 is fixed to the front surface of the screw 5 with a screw 60, and an O-ring 66 keeps airtight. Further, the block 55 is provided with a hole 37 in the upper portion thereof and has a cavity portion 34 having the lid 59 as one wall surface. In the hollow portion 34, stainless steel pipes 54 and 58 are respectively inserted from the left and right as seen in FIG. Although not shown, an O-ring is provided between the stainless steel pipes 54 and 58 and the block 55 to keep airtightness. The openings of the two stainless steel pipes 54 and 58 in the hollow portion 34 are externally fitted and connected by the elastic pipe 28.

As shown in FIG. 4, a stainless steel pipe 54,
From the outside of 58, the lids 57 and 62 are inserted into the block 55 while keeping airtightness. The lids 57 and 62 have holes 33 and 6 which communicate with the fluid passages of the stainless steel tubes 54 and 58, respectively.
5 are provided respectively, and the holes 33 and 65 communicate with the holes 32 and 36 provided in the block 55, respectively.

The hole 32 of the block 55 in FIG.
An O-ring (not shown) communicates with the hole 31 provided in the hole 6, and a filter 44 is provided at the working fluid inlet / outlet port 30 at one end of the hole 31. On the other hand, the hole 36 of the block 55
Communicate with the passage 40 of the block 56 by an O-ring (not shown) while maintaining airtightness, and the passage 40 communicates with the chamber 41. A passage 46 communicating with one end of the third cylinder 50 (FIG. 10) is provided in the chamber 41.

The cavity portion 34 and the chamber 41 communicate with each other through a passage 35 provided in the block 55 and a passage 39 provided in the block 56. The passages 35 and 39 are kept airtight by an O-ring (not shown). As shown in FIGS. 8 and 9, the upper protrusion 45, which is a part of the block 55, is formed in the cavity 34.
The lower protrusions 42, which are integrally fixed to each other by the columns 29 and the screws 49, are arranged above and below the elastic pipe 28. As shown in FIGS. 8 and 9, the block 55 includes a support 29 and a lower protrusion 42.
A plug 67 is provided which is tightly screwed in such a manner that it can be fixed with a screw 49. Further, the block 56 has a hole 47 facing upward, and a passage 38 (FIG. 4) communicating with the outside is provided at the bottom of the hole 47.

An O-ring 43 (FIGS. 8 and 9) is provided between the column 29 and the block 55, and the hole 47 and the cavity 34 are provided.
Keeps airtightness between. In addition, the support column 29 penetrates the block 55 and has a large-diameter piston 48 arranged in the hole 47.
Is in contact with. The large-diameter piston 48 slides in the hole 47 while keeping airtightness. The above configuration is the second valve 70a of FIG.
It is also equipped with.

As shown in FIG. 4, the chamber 41a of the second valve 70a and the hole 47 of the first valve 70 are communicated with each other by the passage 38, and the chamber 41 of the first valve 70 and the hole 47a of the second valve 70a are connected to each other. The passages 38a communicate with each other. The keep valve 200 is configured as described above.

In FIG. 10, the numbers attached in parentheses to the lead lines correspond to the suffixes of the keep valve 200 according to the embodiment of the second invention. Keep valve 200 passage 4
6 is connected to the pipe 51 shown in FIG.
A pipe 52 is connected to a. Pipes 51 and 52 are first
Similar to the embodiment of the invention, the piston 53 is connected to both ends of the inserted third cylinder 50.

Next, the operation will be described. As shown in FIG.
In the keep valve 200, both of the lower protrusions 42 and 42a are initially lowered, and the elastic pipes 28 and 28a are open. On the other hand, the piston 53 of the third cylinder 50 in FIG. 10 is located near the left end, and the piston 53 is moved to the right from this state.

Pressure fluid supply device 1 for working fluid inlet / outlet port 30
When the pressure fluid is supplied at 50, the pressure fluid is supplied to the holes 31, 32, 33, the elastic pipe 28, and the hole 6 as shown in FIG.
5, 36, passage 40, and passage 46 through chamber 41
Through the pipe 51 (FIG. 10), reaches the left chamber 50a of the third cylinder 50 shown in FIG. 10, and presses the piston 53 to the right. The piston 53 is fixed to an external device (not shown), and the initial pressing force of the pressure fluid cannot move the piston 53 integrated with the external device to the right. In this state, the pressure fluid flows through the passages 39 and 3 shown in FIG.
5 to reach the cavity 34.

When the pressure fluid supply device 150 continues to supply the pressure fluid, the pressure existing between the left chamber 50a of the third cylinder 50 shown in FIG. 10 and the cavity portion 34 shown in FIG. 4 unless the piston 53 moves to the right. Fluid pressure continues to rise.

On the other hand, the right chamber 50b of the third cylinder 50 is
Pipe 52 (FIG. 10), passage 46a, chamber 41a, passage 40
a, holes 36a and 65a, elastic pipe 28a, hole 33
Since the working fluid inlet / outlet port 30a communicates with the atmosphere via a, 32a, and 31a, the atmospheric pressure is achieved. The hole 47 communicating with the atmospheric pressure chamber 41a through the passage 38 is also at atmospheric pressure.

The fluid pressure in the cavity 34 acts on the lower protrusion 42, but a pressure difference occurs because the hole 47 is at atmospheric pressure, and the lower protrusion 42 rises as shown in FIGS. Close.

When the pressure fluid supply device 150 continues to supply the pressure fluid, the pressure in the cavity 34 causes the holes 33 to be released.
The internal pressure becomes larger, and this pressure eventually spreads the elastic pipe 28 as shown in FIG.
4, a gap L is created between the elastic pipe 28 and the elastic pipe 28, and the pressure fluid flows into the cavity 34 from the hole 33.

The pressure fluid that has flowed into the cavity 34 passes through the passage 3
5 and 39, from the chamber 41 to the passage 46, the pipe 51 (see FIG.
0) to the left chamber 50a of the third cylinder 50.
The pressure of the pressure fluid at this time is such that the piston 53 can be moved to the right, and the pressure fluid is continuously supplied by the pressure fluid supply device 150 until the piston 53 is moved by a predetermined distance.

When the piston 53 has finished moving a predetermined distance, the pressure fluid supply device 150 is separated from the working fluid inlet / outlet port 30 and the supply of the pressure fluid is stopped. When the pressure fluid is no longer supplied, the elastic pipe 28 shown in FIG. 6 is fitted onto the stainless steel pipe 54 as shown in FIG. 5 to eliminate the gap L.

On the other hand, while the piston 53 in FIG. 10 is moving to the right, the atmospheric pressure air in the right chamber 50b of the third cylinder 50 is pushed out by the piston 53, and the pipe 52 passes through the passage 46a in FIG. , Chamber 41a, passage 40a, hole 36a,
65a, elastic pipe 28a, holes 33a, 32a, passage 3
After passing through 1a, it is discharged from the working fluid inlet / outlet port 30a into the atmosphere. At this time, the filter 44a plays a role of a muffler and has a sound deadening effect.

Next, in order to move the piston 53 to the left, the pressure fluid supply device 150 is connected to the working fluid inlet / outlet port 30a.
To supply pressure fluid. At this time, the keep valve 200 is
Unlike when the piston 53 is moved to the right, the elastic pipe 28 shown in FIG. 4 is not open, but the lower projection 42 of FIG. 5 is raised and the elastic pipe 28 is closed.

When the pressure fluid is supplied from the working fluid inlet / outlet port 30a of the keep valve 200 of FIG. 5 by the pressure fluid supply device 150, the pressure fluid is passed through the passages 31a and the holes 32a, 33.
a, inside the elastic pipe 28a, holes 65a, 36a, passage 40
The chamber a, the chamber 41a, and the passage 46a reach the right chamber 50b of the third cylinder 50 through the pipe 52 of FIG.

However, since there is residual pressure fluid in the left chamber 50a of the third cylinder 50, the right chamber 50b at this time.
The piston 53 cannot be moved to the left by the pressure of the pressure fluid supplied to. Pressure fluids with nowhere to go
The large-diameter piston 48 is pressed downward by penetrating the hole 47 from the chamber 41a through the passage 38.

The residual pressure fluid in the left chamber 50a of the third cylinder 50 urges the lower protrusion 42 upward in the cavity 34, but the large-diameter piston 48 has a pressure receiving area larger than that of the lower protrusion 42. Large size, large diameter piston 48 and support 29
The (lower protrusion 42) descends, the elastic pipe 28 opens, and the keep valve 200 enters the state shown in FIG.

The following operation is the same as when the pressure fluid is supplied to the working fluid inlet / outlet 30, and the lower projection 42a of FIG. 7 moves up from the state of FIG. 4 to the state where the elastic pipe 28a is closed. 5 and 7 are in a symmetrical state, the piston 53 of FIG. 10 moves to the left, and when the piston 53 has moved a preset distance, the pressure fluid supply device 150 is separated from the working fluid inlet / outlet port 30a, and the pressure fluid Stop the supply.

When the supply of the pressure fluid is stopped in the state shown in FIGS. 5 and 7, the lower protrusions 42 and 42a continue to hold the raised or lowered positions, respectively.

[0050]

【The invention's effect】

(First Invention) By using the keep valve 100 of the first invention, the pressure fluid supply device 150 can be installed in the keep valve 1.
When it is separated from 00, the valve is automatically closed, the pressure in the third cylinder 50 can be maintained, and inadvertent movement of the piston 53 can be prevented.

By using the keep valve 100 of the first invention, it is possible to adjust the exhaust start timing of the fluid remaining in the third cylinder 50 and the supply start timing of the pressurized fluid to the third cylinder 50. . For example, by setting the exhaust start timing of the fluid remaining in the third cylinder 50 to be slightly earlier than the supply start timing of the pressure fluid to the third cylinder 50, the pressure of the supplied pressure fluid is relatively close to normal pressure. Even at a low pressure, the frictional force generated between the piston 53 and the inner surface of the third cylinder 50 is overcome, the piston 53 is not pulsated, and the movement of the piston 53 can be stabilized. Therefore, the piston 53 can be moved at a low speed, and smooth movement without pulsation can be obtained.

Further, the speed of the piston 53 can be changed from high speed to low speed by adjusting the pressure of the pressure fluid to be supplied, and it can be used in various fields.

By changing the sizes of the elastic force of the coil springs 8 and 8a, the pressure receiving area S2 of the large-diameter pistons 6 and 6a and the pressure receiving area S1 of the packings 4 and 4a, the piston 53 is changed.
The required moving speed can be set appropriately.

The keep valve 100 of the first invention is simple in structure, requires a small number of parts, does not require difficult processing, is easy to assemble, does not require strict precision in production, and does not cost much to produce. Easy to produce.

(Second invention) Since the spring is not used, the lower protrusions 42 and 4 are not affected even when vibration is generated when an external force is applied to the device.
The operation of 2a (supports 29, 29a) is stable, and the first
It is advantageous over the keep valve 100 of the invention in terms of earthquake resistance. Like the keep valve 100 of the first invention, the parts can be easily procured, and the parts can be manufactured economically without cost.

[Brief description of drawings]

FIG. 1 is a schematic vertical sectional front view of a keep valve of a first invention.

FIG. 2 is a partially vertical front schematic view showing a state where the valve body of the first cylinder is opened in FIG.

FIG. 3 is a schematic partial front view showing a state in which the valve bodies of the first and second cylinders are both opened in FIG.

FIG. 4 is a schematic partial front view in section of the keep valve of the second invention.

5 is a partially vertical front schematic view showing a state where the elastic pipe of the first valve is closed in FIG. 4. FIG.

FIG. 6 is a schematic partial front view showing a state in which a gap is formed between the elastic pipe of the first valve and the stainless steel pipe in FIG.

FIG. 7 is a schematic partial front view showing a state in which the elastic pipe of the second valve is closed in FIG.

8 is a sectional view taken along line VIII-VIII of FIG.

9 is a sectional view taken along line IX-IX in FIG.

FIG. 10 is a structural schematic diagram showing a state in which the keep valve of the first invention and the second invention is connected to a cylinder having a piston inserted therein.

[Explanation of symbols]

3,3a valve body 5, 5a rod 6,6a Large diameter piston (piston) 8, 8a Coil spring (biasing means) 16, 16a O-ring (airtight holding part) 18, 18a Bypass passage (passage) 20, 20a First and second cylinders 28, 28a Elastic pipe 29, 29a prop 34, 34a Cavity (space) 35, 35a passage (first communication passage, fourth communication passage) 36, 36a holes (second communication passage, fifth communication passage) 38, 38a passage (sixth communication passage, third communication passage) 39, 39a passage (first communication passage, fourth communication passage) 40, 40a passage (second communication passage, fifth communication passage) Room 41, 41a (first room, second room) 42, 42a Lower protrusion 45, 45a Upper protrusion 46, 46a passage (7th communication passage, 8th communication passage) 47, 47a hole 50 Third cylinder 53 pistons 54, 54a Stainless steel pipe (first rigid pipe) 55, 55a block 58, 58a Stainless steel pipe (second rigid pipe) 70, 70a First valve, second valve 100,200 keep valve

─────────────────────────────────────────────────── ─── Continuation of the front page (58) Fields surveyed (Int.Cl. ⁷ , DB name) F16K 7/00 F16K 11/00 F16K 31/12

Claims (2)

(57) [Claims] 1. A valve body (3, 3a) is provided at one end,
First and second cylinders (2) of the same shape in which rods (5, 5a) having large-diameter pistons (6, 6a) are inserted at the other end.
0, 20a) are arranged adjacent to each other, branch passages (2, 2a) communicating with the outside of the cylinder are provided in the first and second cylinders (20, 20a) near the center, respectively, and the first cylinder The large-diameter piston (6a) having the large-diameter piston (6a) in which the large-diameter piston (6a) of the second cylinder (20a) is inserted extends from near the center of the (20) to the end side of the second cylinder (20a). First bypass passage (18)
The large diameter piston (6) of the large inner diameter portion (10) in which the large diameter piston (6) of the first cylinder (20) is inserted from near the center of the second cylinder (20a) to the cylinder (20). Bypass passage (18a) leading to the end side of the
Is provided, and is connected to the branch passage (2) and the first bypass passage (18).
Airtightness is maintained between the inner diameter part (10) and
Large with branch passage (2a) and second bypass passage (18a)
Airtightness is also maintained between the inner diameter portion (10a) and the spring (8, 8a) for urging the large diameter piston (6, 6a) to the side opposite to the branch passages (2, 2a) and the cylinder (20,
20a) and is compressed by the spring (8, 8a),
The rods (5, 5a) integrated with (6, 6a) are
When moving in the two cylinders (20, 20a), the first,
The valve body (3, 3) is provided in the second cylinder (20, 20a).
a) and abut further movement of the rod (5, 5a)
A valve seat (27, 27a) is provided to prevent the valve body (3, 3a) from contacting the valve seat (27, 27a).
When the valve body (3, 3a) is housed,
Inside diameter part (11, 1) in the second cylinder (20, 20a)
1a), the branch passages (2, 2a) and the first and second bars.
Keep the airtightness between the Ypus passages (18, 18a)
The keep valve is characterized by 2. A pair of first rigid pipes (54, 54) in a box (55, 55a) having a space (34, 34a) therein.
a) and the second rigid pipes (58, 58a) are kept airtight from the outside of the box (55, 55a) to the space (3).
4, 34a) and the spaces (34,
34a) and are arranged on a straight line in the horizontal direction so as to face each other, and the first rigid pipe (54, 54,
54a), and one elastic pipe (28, 28) on the outer circumference of the two opposing openings of the second rigid pipe (58, 58a).
a) both ends thereof are respectively covered and connected, and the ends of the first rigid pipes (54, 54a) outside the box (55, 55a) communicate with the outside, and the elastic pipes (28, 28)
An upper protrusion (45, 45a) is provided on the upper inner wall surface of the box (55, 55a) just above a), and a lower portion is provided just below the upper protrusion (45, 45a) and the elastic pipe (28, 28a). Protrusions (42, 42a) are provided, and the lower protrusion (4
2, 42a) are provided with columns (29, 29a),
The box (55, 55a) communicates with the space (34, 34a), and the support column (29, 29a) is slidable in the hole (37,
37a) is provided, communicates concentrically with the holes (37, 37a), and has a larger diameter than the holes (37, 37a) (47, 4).
7a) Airtight and slidable large-diameter piston (48, 4
8a) is provided, and the large-diameter piston (48, 48)
a) is a pair of first valve (70) and second valve (70a) that are in contact with the support columns (29, 29a),
The bottom of the space (34) of the first valve (70), the second rigid pipe (58) and the hole (47a) of the second valve (70a) are respectively the first communication passage (35, 39) and the second communication passage (35). 36, 40) and the third communication passage (38a) communicate with the first chamber (41), and the first chamber (41) is a third cylinder in which the piston (53) is inserted through the seventh communication passage (46). The second valve (70) is in communication with one end of (50).
The space (34a) of a), the second rigid pipe (58a) and the bottom of the hole (47) of the first valve (70) are respectively the fourth.
Communication path (35a, 39a), fifth communication path (36a, 40a
a), the sixth communication passage (38) communicates with the second chamber (41a), and the second chamber (41a) communicates with the other end of the third cylinder (50) through the eighth communication passage (46a). A keep valve that is characterized by