JP2600913Y2 - Flow control 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 flow valve for controlling a flow rate of a fluid to a constant amount in response to a change in supply pressure.

[0002]

2. Description of the Related Art Generally, a gas appliance or the like incorporates a flow control valve (hereinafter, referred to as a control valve) for controlling a gas flow rate to a constant amount. This control valve has a role of ensuring a stable combustion gas amount even when the gas supply pressure fluctuates. The constant flow valve as its one example is given in Figure 4 will be described.

The control valve 40 has a substantially cylindrical lid 43 having a gas inlet and a substantially cylindrical body 45 having a gas outlet.
Face each other at their flange surfaces 44 and 45, and are fixed with a diaphragm valve 54 therebetween. Therefore,
The primary chamber 42 is formed on the lid 43 side, which is on the upstream side of the diaphragm valve 54, and the secondary chamber 46 is formed on the main body 45 side. A valve seat 51 having a gap facing the diaphragm valve 54 is provided at the center of the main body 45, and a communication hole 50 for guiding gas to an outlet is formed at the center thereof. The communication hole 50 is sufficiently large because it serves as a flow path for guiding the controlled gas to the outlet. A spring 47 is provided on the outer periphery surrounding the valve seat 51 and urges the diaphragm valve 54 in the valve opening direction. The diaphragm valve 54 has a through hole 53 located outside the portion where the spring 47 abuts, and the gas in the primary chamber 42 flows through the through hole 53 into the secondary chamber 46.

When the gas pressure P0 is applied to the primary chamber 42, the gas passes through the through hole 53 and flows into the secondary chamber 46 to reach the pressure P1, and then passes through the gap between the diaphragm valve 54 and the valve seat 51. The pressure becomes P2. The diaphragm valve 54 has P0 and P
1, and acts on the pressure receiving surface to act in the valve closing direction (downward in the figure). On the other hand, the diaphragm valve 54 is acted on by a spring 47 in the valve opening direction.

When the supply pressure P0 increases and the pressure of P1 increases and the flow rate increases, the through-hole 53 is a fixed flow path, so that P
The differential pressure between 0 and P1 also increases. Therefore, the force due to the differential pressure exceeds the force of the spring 47 and narrows the gap between the diaphragm valve 54 and the valve seat 51. When the supply pressure P0 decreases and the pressure of P2 decreases, and the flow rate decreases, the differential pressure between P0 and P1 also decreases because the through hole 53 is a fixed flow path. Therefore, the force due to the differential pressure is defeated by the force of the spring 47, and the gap between the diaphragm valve 54 and the valve seat 51 is widened.

When the flow resistance after the communication hole 50 of the valve seat 51 decreases and the flow rate increases, the pressure at P2 decreases and the differential pressure between P0 and P1 increases. Therefore, the force due to the differential pressure exceeds the force of the spring 47 and narrows the gap between the diaphragm valve 54 and the valve seat 51.

On the other hand, when the flow resistance after the communication hole 50 of the valve seat 51 increases and the flow rate decreases, the pressure of P2 increases and the differential pressure between P0 and P1 decreases. Therefore, the force due to the differential pressure is defeated by the force of the spring 47, and the gap between the diaphragm valve 54 and the valve seat 51 is widened. As described above, the diaphragm valve 54 receives the differential pressure between P0 and P1 on the pressure receiving surface and acts on the diaphragm valve 5 by the force acting in the valve closing direction.
4 acts to balance the force acting in the valve opening direction. Therefore, if the load of the spring 47 is constant, the differential pressure between P0 and P1 is also constant, and the flow rate passing through the through hole 53 is constant.

[0008]

However, even if an attempt is made to control the flow rate using the above-mentioned control valve as it is, various problems actually occur. For example, a spring receiver is required to evenly apply the spring load to the diaphragm valve, a guide to prevent deformation of the through hole, and a member to prevent deformation of the valve seat contact portion of the diaphragm valve are required. become.
In addition, since the through hole is eccentrically opened outside the valve seat abutting portion of the diaphragm valve, the diaphragm valve is liable to be inclined and unstable, so that there is a problem that it is difficult to obtain stable performance. Also, since the diaphragm is held airtight, there is a fear that fluid leakage to the outside may occur due to poor sealing at the flange surface. An object of the present invention is to solve the above-mentioned problems and to provide an inexpensive, small, and simple control valve.

[0009]

In order to solve the above-mentioned problems, a flow control valve according to the present invention comprises an elastic film having a primary passage hole formed in the center while partitioning a flow path. the downstream-passage and a Setsukabe specifications Ru partition, the elasticity and valve seat tapered seat portion is formed with a primary passage hole periphery and gaps face to face in the first pass the pores of the membrane, the valve seat
A plurality of secondary passage holes surrounding the first passage hole are provided in the partition wall, and the gap between the peripheral portion of the primary passage hole and the valve seat is changed by the displacement of the elastic film.

Further, in the flow valve according to the second invention, in the first invention, a communication hole having a diameter smaller than that of the primary passage hole is provided at a central portion of the valve seat so as to face the primary passage hole of the elastic membrane. It is the gist that it is formed.

In a third aspect of the present invention, in the flow valve according to the first or second aspect, the valve seat is screwed and mounted on the partition wall, and the periphery of the primary passage hole and the valve seat are adjusted by adjusting the screwing position. The gist is that the gap of is finely adjusted.

[0012]

The flow control valve of the present invention having the above-mentioned structure operates by utilizing the elastic force of the elastic film. The fluid passes through the primary passage hole in the center of the elastic membrane , and one is tapered with the periphery of the primary passage hole.
Through the gap with the sheet-shaped portion, and through the secondary passage hole provided in the partition wall to the downstream side of the control valve , the other is a valve seat
Pass through and merge downstream. At this time, when the fluid passes through the primary passage hole in the center of the elastic film, a pressure difference is generated before and after the elastic film, and the elastic film is deformed downstream according to the degree of the pressure difference. The greater the pressure difference acting on the elastic film elastic film to reduce the gap between the case Cormorants tapered seat portion facing the elastic film when the pressure difference becomes small to increase the gap between the tapered seat. Therefore, an elastic film when there is a variation in the supply pressure
A predetermined amount of flow rate aperture of the tapered seat portion is changed
To control. Thus, there is a gap with the periphery of the primary passage hole.
The elastic film is formed because the tapered sheet portion
Small change in aperture with respect to the amount of deformation
Control with high accuracy. Also, the secondary passages surround the valve seat.
Since there are multiple holes and there is no bias in the flow, an elastic membrane
Is difficult to tilt and controls the flow rate stably.

In the control valve according to the second aspect of the present invention, the fluid passing through the primary passage hole of the elastic membrane passes not only through the secondary passage hole but also through the communication hole provided at the center of the valve seat. Therefore, even if the supply pressure of the fluid becomes excessive and the gap between the elastic membrane and the valve seat is closed, the flow path by the communication hole is always ensured, and the flow of the fluid does not stop.

In the control valve of the third invention, since the valve seat is screwed into the partition wall, the gap between the peripheral edge of the primary passage hole of the elastic membrane and the valve seat can be finely adjusted, so that mass production is possible. Thus, a control valve that absorbs variations in individual performance and matches the target performance can be obtained.

[0015]

DESCRIPTION OF THE PREFERRED EMBODIMENTS In order to further clarify the configuration and operation of the present invention described above, a preferred embodiment of the flow control valve of the present invention will be described below. FIG. 1 shows a gas flow control valve as one embodiment. The gas flow control valve 1 (hereinafter, simply referred to as a control valve) is provided in the middle of the gas pipeline GP.
Case 2, elastic film 3, valve seat 4, seat retainer 5, ring 6
Consists of

The case 2 is a substantially cylindrical body fitted into the gas flow path, and has a partition wall 7 for partitioning the flow path on the downstream side (lower side in the drawing). A screw hole 8 is formed in the center of the partition wall,
The valve seat 4 is screwed into the screw hole 8 and attached. Further, a step portion 11 is formed on the inner cylindrical wall surface 10 of the case 2 by changing the thickness. The elastic film 3 is placed on the step portion 11, and the elastic film 3 is fixed by a ring 6 via a sheet retainer 5.

[0017]

[Effect of the Invention] As described in detail above, claim 1 of the present invention
The described flow control valve has a small number of components, and can perform flow control at a small size and at low cost. Further, since the device is incorporated in the flow channel, the space for the device to be incorporated is not restricted, and since there is no connecting portion in contact with the outside air, the fluid does not leak out of the flow channel. Furthermore, a plurality of secondary passage holes are provided to surround the valve seat.
The elastic membrane is hard to tilt, and stable flow performance is obtained.
Can be In addition, the tapered sheet portion allows the elastic film to change.
Make the change of the opening degree small and appropriate for
The amount is controlled. Also, the flow rate control according to claim 2 of the present invention.
The control valve stops the fluid even if the supply pressure of the fluid becomes excessive.
Does not occur. Claims of the present invention
3. The flow control valve described in (3) finely adjusts the opening between the valve seat and the elastic membrane.
Can improve the accuracy of flow characteristics.
You.

The valve seat 4 faces the elastic film 3 and the seat portion 1
2 and a gap is provided near the primary passage hole 15 of the elastic film 3. A communication hole 13 is formed in the center of the seat portion 12 of the valve seat 4 and communicates downstream. The screw-in type valve seat 4 can be moved forward and backward by a driver or the like, so that the gap between the valve seat 4 and the elastic film 3 can be finely adjusted.

The partition wall 7 of the case 2, which is the mounting surface of the valve seat 4, has a hole 14 (hereinafter referred to as a secondary passage hole) having a sufficient area as an escape flow path for gas downstream. A plurality of seats are opened so as to surround the seat 4.

As described above, the control valve of the present embodiment
A ring 6, a sheet retainer 5, an elastic film 3, and a valve seat 4 are assembled in this order from the upstream side as a single unit. The ring 2 is mounted on a step formed in the gas pipeline GP.
Fixed at 0.

Next, the operation of the control valve will be described. FIG.
Shows the operating state of the control valve, and FIG. 3 shows the control characteristics of the control valve. For convenience of explanation, the first chamber 16 is located on the upstream side of the elastic membrane 3, the second chamber 17 is located between the elastic membrane 3 and the partition 7 of the case 2, and the downstream is located on the boundary of the partition 7. Called third chamber 18. The state (a) in FIG. 2 shows the state on the section A on the flow characteristic in FIG. 3, and the state (b) corresponds to the state on the section B on the flow characteristic, respectively.

In FIG. 2A, when the gas passes through the primary passage hole 15 of the elastic film 3 due to the supply pressure P0 from the first chamber 16, the gas enters the second chamber 17 and is reduced in pressure to P1. Part of the gas sent to the second chamber 17 enters the third chamber 18 as a fixed flow path passing through the communication hole 13 of the valve seat 4, and the rest passes through the gap between the elastic membrane 3 and the valve seat 4. After passing through, it enters the third chamber 18 through the secondary passage hole 14 of the case and merges. Thus, the gas pressure becomes P2 and the flow rate becomes Q0. The force applied to the elastic film 3 depends on the pressure difference between the first chamber 16 and the second chamber 17. If the force is smaller than the elastic force of the elastic film 3, the elastic film 3 does not deform. Therefore, the flow rate changes in the section A on the flow rate characteristic in FIG. 3 in proportion to the supply gas pressure.

When the supply pressure P0 from the first chamber 16 further increases, the differential pressure between the first chamber 16 and the second chamber 17 increases, and the force applied to the elastic film 3 becomes larger than the elastic force.
For this reason, as shown in FIG. 2B, the elastic film 3 is not kept stationary and is deformed to narrow the opening of the gap with the valve seat 4. When the supply pressure P0 decreases, the pressure difference between the first chamber 16 and the second chamber 17 decreases, and the elastic force of the elastic film 3 increases the degree of opening of the gap with the upward rotation valve seat 4. Therefore, the opening degree of the gap between the elastic film 3 and the valve seat 4 is changed according to the change of the supply pressure. As a result, the flow rate changes on the section B on the flow rate characteristic in FIG. 3 regardless of the supply pressure, and the downstream flow rate Q0 is controlled to a constant value.

When the passage resistance after the communication hole 13 of the valve seat 4 decreases and the flow rate increases, the differential pressure between P0 and P1 increases, and the force applied to the elastic film 3 is larger than the elastic force. Become. Therefore, the opening degree of the gap between the elastic film 3 and the valve seat 4 is reduced. Conversely, when the flow resistance after the communication hole 13 of the valve seat 4 increases and the flow rate decreases, the differential pressure between P0 and P1 decreases, and the elastic force between the elastic membrane 3 and the valve seat 4 is lost due to the elastic force. The opening of the gap is widened, and the flow rate Q0 is controlled to a constant value. The elastic film 3 receives the differential pressure between P0 and P1 on the pressure receiving surface, and
Force acting in a direction to narrow the opening of the gap between the valve seat 4 and
It works to balance with the force acting in the direction to widen the gap by its own elastic force. Therefore, if the elastic force is constant, P0
, P1 also becomes constant, and the flow rate Q0 passing through the primary passage hole 15 becomes constant.

If the gas supply pressure P0 exceeds the desired control range and becomes excessive, the force applied to the elastic film 3 due to the pressure difference between the first chamber 16 and the second chamber 17 is increased by the elasticity. Much larger than the force. For this reason, the elastic film 3 is greatly deformed and closes the opening of the gap with the valve seat 4, but the gas passes through the fixed flow passage of the communication hole 13 of the valve seat 4 and the third chamber 18.
Gas flow does not stop. Therefore, there is no problem that the supply pressure P0 of the gas temporarily becomes excessively high for some reason and the stop state continues.

To make the flow characteristics ideal, the elastic film 3
The elastic force of the elastic membrane 3, the primary passage hole diameter, the pressure receiving area of the elastic membrane 3, the thickness of the elastic membrane 3, the shape of the seat portion of the elastic membrane 3, the seat diameter of the valve seat 4, the shape of the seat portion of the valve seat 4, The diameter of the communication hole of the valve seat 4, the diameter of the secondary passage hole of the case 2, the position of the secondary passage hole of the case 2, and the gap between the elastic film 3 and the seat portion of the valve seat 4 are respectively optimally selected.

The valve seat 4 is screwed into the case 2, and the degree of opening with the elastic film 3 can be finely adjusted by a screwdriver or the like. Therefore, the accuracy of the flow characteristics during mass production can be further improved. Further, other components can be made common to devices having different flow rates only by adjusting the clearance of the valve seat 4 or replacing the valve seat 4. In addition, it is more convenient to provide an adjustment port from the outside of the flow path in the installed state of the device, and the adjustment is more convenient.Also, since the entire unit can be built in the flow path as it is, there is no restriction on the space of the installed device, Any flow path can be easily changed to a flow rate controlled flow path. Furthermore, it is compact and easy to handle, so that it can have versatility. Further, since it is incorporated in the flow path as it is, there is no connection part in contact with the outside air, and there is no possibility that gas leaks to the outside.
Although the embodiments of the present invention have been described above, the present invention is not limited to these embodiments, and it is needless to say that the present invention can be implemented in various modes. For example, the material of the elastic film 3 is not limited to rubber or the like, and various materials such as synthetic resin can be used. Further, the present invention is not limited to the control of the gas flow rate, but may be applied to the control of the flow rate of a liquid such as water or oil.

[0028]

As described in detail above, the flow control valve according to the present invention has a small number of components and can perform flow control at a small size and at low cost. Further, since the device is incorporated in the flow channel, the space for the device to be incorporated is not restricted, and since there is no connecting portion in contact with the outside air, the fluid does not leak out of the flow channel.

[Brief description of the drawings]

FIG. 1 is a schematic configuration diagram of a flow control valve as one embodiment.

FIG. 2 is an explanatory diagram of the operation.

FIG. 3 is a flow characteristic diagram.

FIG. 4 is a schematic configuration diagram of a flow control valve as a conventional example.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Gas flow control valve 2 Case 3 Elastic membrane 4 Valve seat 7 Partition wall

──────────────────────────────────────────────────続 き Continuation of the front page (56) References JP-A 60-20616 (JP, U) JP-A 55-171761 (JP, U) JP-A 52-54924 (JP, U) (58) Field (Int.Cl. ⁶ , DB name) F16K 17/26 F16K 7/17

Claims (3)

(57) [Scope of request for utility model registration] Comprising an elastic film center primary passage holes are formed with 1. A partitioning the flow path, and a Setsukabe specifications Ru partition the downstream flow path face to face with the elastic film, the primary of the elastic membrane A valve seat having a tapered seat portion facing the passage hole and having a gap with the periphery of the primary passage hole.
And a plurality of secondary passage holes surrounding the valve seat are provided in the partition wall, and a gap between the peripheral portion of the primary passage hole and the valve seat is changed by displacement of the elastic film. valve. 2. The flow rate according to claim 1, wherein a communication hole having a diameter smaller than that of the primary passage hole is formed in a central portion of the valve seat so as to face the primary passage hole of the elastic membrane. Control valve. 3. The valve seat according to claim 1, wherein the gap between the peripheral edge of the primary passage hole and the valve seat is finely adjusted by adjusting the screwing position of the valve seat. Item 3. A flow control valve according to Item 2.