JP2009036364A - Control valve - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a control valve preventing leakage from a fastening portion of an upper cover and a valve body and easily assembled/disassembled. <P>SOLUTION: The valve body 2 is provided with an inflow passage 8 (primary side passage), an outflow passage 9 (secondary side passage), a valve chamber 12 provided between the both passages 8, 9, and a cage-shaped guide 3 to which a plug 1 is inserted. On the valve chamber 12, a flat gasket 6, a seat ring 5 having a wedge cross section and a flowing hole 5c positioned in the center and a gasket 4 having a delta (triangle) cross section are placed in this order. The plug 1 is inserted to the cage-shaped guide 3. At this time, a gland packing 7 is interposed between the plug 1 and the cage-shaped guide 3. <P>COPYRIGHT: (C)2009,JPO&INPIT

Description

  The present invention relates to a control valve that controls the amount of hydrogen supplied from a tank of a hydrogen station supplied to a fuel cell vehicle.

  In a normal control valve, a partition that partitions the inflow path side (primary side) and the outflow path side (secondary side) is provided inside the valve body, and a seat ring having a fluid circulation hole is disposed in the opening of the partition wall. ing. When the plug (valve element) having the flow characteristic part is seated on the seat surface of the seat ring, the plug is fully closed, and when separated, the fluid flows into the secondary side through the gap between the flow characteristic part of the plug and the seat ring (for example, , See Patent Document 1).

Control valves are also used in hydrogen stations that supply hydrogen to fuel cell vehicles. Specifically, it is built in a dispenser that supplies hydrogen to a fuel cell vehicle and controls the amount of hydrogen supplied from the tank. This control valve controls the flow rate of the high-pressure hydrogen gas of 35 MPa when the travelable distance of the fuel cell vehicle is about 250 km.
FIG. 3 is a longitudinal sectional view showing a conventional structure of a control valve used for controlling the flow rate of high-pressure hydrogen gas. As a high-pressure control valve as shown in FIG. 3, it is common to place a plug on the secondary side when the front part is the primary side and the rear part is the secondary side from the most contracted part (throttle part). Is.

The control valve shown in FIG. 3 has the following characteristics.
(1) The plug 1 and the gland part (gland packing 7) are accommodated in the upper lid 10, and the upper lid 10 and the valve body 2 are fastened with a fastening member (a torque wrench or the like) via the spiral gasket 11.
(2) The fluid that has flowed into the valve body 2 from the inflow path (primary side path) 8 from below is a gap between the flow hole 5c in the center of the seat ring 5 and the needle body (flow rate characteristic section) 1a at the tip of the plug 1 ( It passes through the most contracted flow part) and collides with the seating part 1b on the peripheral surface of the lower end of the plug 1. Then, it flows out of the valve body 2 through an outflow passage (secondary passage) 9 provided above the seating portion 1b.
(3) A pressing force is generated downward by tightening the upper portion of the upper lid 10 with a fastening member. The lower lid 10 is brought into contact with the flange portion of the seat ring 5 and sealed with the above-mentioned pressing force (hereinafter referred to as other force seal structure).

4 is an enlarged cross-sectional view showing another force type seal structure of the control valve of FIG. The control valve shown in FIG. 3 has a different force seal structure that seals with the tightening torque (external force) of the upper lid 10.
In FIG. 4, in the split type structure of the upper lid 10 and the valve body 2 of the above feature (1), the fastening portion between the upper lid 10 and the valve body 2 is loosened due to external factors such as vibration, pressure history, thermal history, etc. There was a risk of leakage.
Further, when handling a fluid having a small molecular weight and easily leaking, such as hydrogen, it is difficult to completely eliminate leakage even when fastened with an appropriate torque.
Furthermore, in the other force type seal structure of the feature (3), when the fluid pressure condition is a high pressure of 35 MPa, the tightening torque of the upper lid 10 is 1 kN · m or more, and it is extremely difficult to disassemble and assemble.

Japanese Patent Laid-Open No. 10-160032

Since the conventional control valve is configured as described above, the fastening portion between the upper lid and the valve body is loosened due to the influence of vibration, pressure, and heat, and from the boundary portion (fastening portion) between the two. There was a problem that leakage occurred.
In addition to the fact that the tightening operation of the fastening portion is essential, there is also a problem that a certain amount of time is required for the tightening operation because the certainty is also required.
Furthermore, when the fluid is high pressure, the tightening torque of the upper lid becomes excessive, and there is a problem that disassembly and assembly are difficult.

The present invention has been made to solve the above-described problems, and an object of the present invention is to provide a control valve that prevents leakage from a fastening portion between an upper lid and a valve body.
It is another object of the present invention to provide a control valve that can be easily assembled and disassembled.

  The control valve according to the present invention is a control valve that controls, by a plug, a flow rate of a fluid that passes through a flow hole in the center of the seat ring inside the valve body, and receives the pressure of the fluid on a peripheral surface of the seat ring to receive the seat A fluid pressure seal portion for sealing the ring is provided.

  In the regulating valve according to the present invention, the fluid pressure seal portion is in contact with the seat ring having a circumferential surface with a tapered cross section whose width increases in the fluid flow direction, and the circumferential surface of the seat ring. The cross section disposed in contact with each other is constituted by a gasket having a tapered peripheral surface.

  The control valve according to the present invention is characterized in that the valve body is integrally formed so as not to be divided.

According to this invention, the seat ring is sealed by receiving the pressure of the fluid, so that the tightening torque of the upper lid can be reduced.
Further, when the fluid is high pressure, a sufficient sealing effect can be obtained without an upper lid.

According to the present invention, since the fluid pressure seal portion is constituted by the seat ring and the gasket by bringing the circumferential surfaces having a tapered cross section into contact with each other, the tightening torque of the upper lid can be reduced.
Further, when the fluid is high pressure, a sufficient sealing effect can be obtained without an upper lid.

According to the present invention, the number of parts can be reduced by eliminating the upper lid and integrally forming the valve body so as not to be divided.
Moreover, the effect which becomes unnecessary [clamping operation | work of an upper cover and a valve main body] is acquired.
Furthermore, there is also an effect that no fluid leaks from the boundary portion (fastening portion) between the upper lid and the valve body.

Embodiment 1 FIG.
Embodiment 1 of the present invention will be described below. 1 is a longitudinal sectional view showing a control valve according to Embodiment 1 of the present invention.
In FIG. 1, the valve body 2 includes an inflow passage 8 (primary side passage), an outflow passage 9 (secondary side passage), a valve chamber 12 provided between the two, and a cage into which the plug 1 is inserted. A shape guide 3 is provided.
In the valve chamber 12, a flat gasket 6, a seat ring 5 having a wedge-shaped cross section and a flow hole 5c in the center, and a gasket 4 having a delta-shaped (triangular) cross section are placed in this order.
The plug 1 is inserted into the cage-shaped guide 3. At that time, a gland packing 7 is interposed between the plug 1 and the cage-shaped guide 3.

  As the sealing members such as the gaskets 4 and 6, the gland packing 7, and the seat ring 5, a material mainly composed of a resin excellent in heat resistance, corrosion resistance, and sealing property (flexibility) such as PTFE is used. For other members, metals having excellent corrosion resistance such as stainless steel are used.

Next, the operation will be described. The fluid that flows into the valve body 2 from the inflow path 8 reaches the valve chamber 12.
In the valve chamber 12, a needle body (flow rate characteristic portion) 1 a provided at the tip of the plug 1 is inserted into a flow hole 5 c provided in the center of the seat ring 5 to form a most contracted flow portion serving as a gap portion therebetween. To do. As the needle body 1a moves through the flow hole 5c, the flow rate is reduced, and the flow rate of the fluid passing through the flow hole 5c is adjusted.
In FIG. 1, the flow rate of the fluid passing through the most contracted flow portion increases as the most contracted flow portion expands as the needle body 1a rises. As the needle body 1a is lowered, the most contracted flow portion is reduced and reduced. When the needle body 1a continues to descend as it is, the needle body 1a is finally fully closed.
The fluid that has passed through the most contracted flow portion flows out of the valve body 2 from the outflow passage 9.

  As shown in FIG. 1, the valve body 2 of the present control valve does not have a separable top cover, and the valve body 2 itself is an integrally molded product. Alternatively, the valve main body 2 may be divided into a plurality of parts and then integrally formed by welding or the like so as not to be divided. Therefore, there is no fastening portion between the upper lid and the valve main body that the control valve having the conventional structure has, and leakage from the same portion does not occur.

Next, the configuration of the fluid pressure seal portion 13 will be described. FIG. 2 is an enlarged sectional view showing a self-closing seal structure of the control valve of FIG. FIG. 2 shows an L-shaped inner peripheral surface (seat) in which a tapered seat portion 1b provided above the proximal end portion of the needle body 1a of the plug 1 is provided above the flow hole 5c of the seat ring 5. The fully closed state seated on the surface 5b) is shown.
In FIG. 2, the fluid pressure seal portion 13 is a portion that receives the pressure of the fluid on the peripheral surface of the seat ring 5 and seals the seat ring 5 (hereinafter referred to as a self-closing seal).

On the outer peripheral surface of the seat ring 5, a portion having a tapered section (hereinafter referred to as an outer peripheral surface tapered portion 5 a) whose width increases toward (along) the fluid flow direction is formed.
Further, a portion having a tapered cross section (hereinafter referred to as an inner peripheral surface taper portion 4 a) opposite to the outer peripheral surface taper portion 5 a is formed on the inner peripheral surface of the gasket 4.
And the outer peripheral surface taper part 5a and the inner peripheral surface taper part 4a are contact | abutted and arrange | positioned, and the fluid pressure seal part 13 is comprised.
Further, a gasket 6 is disposed in contact with the lower surface of the seat ring 5 facing the bottom surface of the cage-shaped guide 3.

Next, the operation of the fluid pressure seal part 13 will be described. First, fluid pressure is applied to the gasket 4 in the direction of the arrow in FIG.
The gasket 4 presses the outer peripheral surface taper portion 5a of the seat ring 5 that contacts the inner peripheral surface taper portion 4a.
The outer peripheral edge of the seat ring 5 abuts against the inner wall of the cage-shaped guide 3. Further, the seating portion 1 b of the plug 1 is seated on the seat surface 5 b of the seat ring 5.
The gasket 6 supports the seat ring 5 from the lower side against the pressure of the fluid, so that the peripheral portion of the seat ring 5 is compressed by the bottom surface portion of the cage-type guide 3 under high pressure and deformed more than necessary. To prevent.

The fluid pressure seal portion 13 prevents seat leakage, and the seal portion formed by the seat surface 5b of the seat ring 5 and the seat portion 1b of the plug 1 prevents seat leakage.
That is, the self-closed seal using the pressure of the fluid is constituted by a combination (wedge-shaped structure) of the seat ring 5 having a wedge-shaped section and the gasket 4 having a delta-shaped section.

As described above, according to the first embodiment, even when the upper lid and the valve body are divided as in the prior art, the seat ring 5 is sealed by receiving the pressure of the fluid. Can be reduced.
Further, when the fluid to be used is a high pressure, the sealing performance of the self-closing seal is improved, so that a sufficient sealing effect can be obtained without tightening the upper lid.
Furthermore, since the fluid pressure seal portion 13 is constituted by a combination of the seat ring 5 having a wedge-shaped section and the gasket 4 having a delta-shaped section, an effect of facilitating the assembly can be obtained.

When the fluid is high pressure, the upper lid is eliminated (upper lid-less structure), and the valve body 2 is integrally formed so as not to be divided, thereby reducing the number of parts (for example, the upper lid 10 and the spiral gasket 11 in FIG. 3). be able to.
At the same time, it is possible to obtain an effect that the tightening operation between the upper lid and the valve main body is unnecessary.
Moreover, since the boundary part (fastening part) between an upper cover and a valve main body does not exist, the effect that the leak of the fluid from the part does not arise at all is also acquired.

  In the above description, expressions such as up, down, left, and right are used for convenience, but the actual installation direction of the valve device is various, and is not limited to the direction used in the above description.

It is a longitudinal cross-sectional view which shows the control valve which concerns on Embodiment 1 of this invention. It is an expanded sectional view which shows the self-closing seal structure in the control valve of FIG. It is a longitudinal cross-sectional view which shows the conventional structure of the control valve used for the flow control of high pressure hydrogen gas. It is an expanded sectional view which shows the other force type seal structure in the control valve of FIG.

Explanation of symbols

1 Plug 1a Needle body (flow characteristics)
DESCRIPTION OF SYMBOLS 1b Seating part 2 Valve body 3 Cage type guide 4 Gasket 4a Inner peripheral surface taper part 5 Seat ring 5a Outer peripheral surface taper part 5b Seat surface 5c Flow hole 6 Gasket 7 Gland packing 8 Inflow path (primary side passage)
9 Outflow passage (secondary passage)
10 Upper lid 11 Spiral gasket 12 Valve chamber 13 Fluid pressure seal part

Claims (3)

In the control valve that controls the flow rate of the fluid passing through the flow hole in the center of the seat ring inside the valve body by a plug,
A regulating valve comprising a fluid pressure seal portion that receives the pressure of the fluid and seals the seat ring on a peripheral surface of the seat ring. The fluid pressure seal part is
The seat ring having a circumferential surface with a tapered cross section that increases in width in the fluid flow direction;
2. The control valve according to claim 1, wherein a cross section of the seat ring that is in contact with the peripheral surface includes a gasket having a tapered peripheral surface.   The control valve according to claim 1, wherein the valve body is integrally formed so as not to be divided.

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