JP2000028010A - Valve device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To improve the sealability by providing a bead comprising a rubber- like elastic member to be attached/detached to/from a valve seat on a seal part of a valve element, and integrating a seal lip higher than the bead with a transfer fluid side of the bead to prevent the leakage of a transfer fluid in closing a valve while permitting the defective forming. SOLUTION: A seal member 21 comprising a rubber-like elastic member is fitted to a lower surface of a seal part 8a of a valve element 8, a bead to be attached/detached to/from a valve seat 22 is integrated with the seal member 21, and a seal lip 24 higher than the bead 23 is integrated with a transfer fluid side, i.e., an inner circumferential side of the bead 23. Even when any forming inconveniences such as inclination and distortion are present in the valve seat 22, and the bead 23 can not be brought into contact with the valve seat 22 in closing a valve, the seal lip 24 follows the inclination or distortion of the valve seat 23, and is brought into contact with the valve seat 22. Excellent sealability over the whole circumference of the valve seat 22 can be ensured, and the transfer fluid can surely be prevented from leaking between the valve seat 22 and the valve element 8 in closing the valve.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a valve device for switching the opening and closing of a flow path.

[0002]

2. Description of the Related Art Conventionally, a valve device shown in FIG. 3 has been known and is configured as follows. This valve device is used as an intercooler bypass valve in an intake system of an internal combustion engine such as a vehicle.

First, a resin valve body 52 fixed to an internal combustion engine or the like via a bracket 51 is provided, and a flexible diaphragm 53 is provided inside the valve body 52. A rod 54 made of resin is connected to an operating portion of the diaphragm 53.
A valve element 55 is formed integrally with the tip of the rod 54. The valve body 55 is provided with the diaphragm 53 and the rod 5
4, the valve body 52 is displaced in the axial direction with the actuation of the valve seat 4, and in conjunction with this, comes into contact with and separates from the valve seat 56 integrally formed in the valve body 52 to open and close the valve hole 57 inside the valve seat. As a result, the valve hole 57 and the valve chamber 5
The flow path 61 reaching the exhaust port 60 via the opening 9 is opened and closed. The diaphragm 53 and the rod 54 are constantly displaced downward by being pressed by a spring 63 installed in a negative pressure chamber 62 provided above the diaphragm 53, whereby the valve body 55 is seated on the valve seat 56. The valve hole 57 is closed.

In this closed state, the valve body 5
When a negative pressure whose absolute value is equal to or larger than a predetermined value is introduced into the negative pressure chamber 62 from the negative pressure port 64 provided in the pressure chamber 2, the negative pressure causes the diaphragm 53 and the rod 54 to resist the elasticity of the spring 63. And the valve element 55 is
6, the valve hole 57 is opened, and the flow path 61 is opened. When the absolute value of the negative pressure introduced into the negative pressure chamber 62 changes below a predetermined value in this valve open state, the elasticity of the spring 63 causes the diaphragm 53 and the rod 5 to move downward.
4, the valve element 55 is seated on the valve seat 56 to close the valve hole 57, and the flow path 61 is closed. The intercooler bypass valve has a function of automatically adjusting the magnitude of the supply pressure by opening the valve when the magnitude of the supply pressure in the intake system is excessive as described above and recirculating a part of the pressure that is too high. To fulfill.

[0005] However, the conventional valve device has the following disadvantages.

That is, from the viewpoint of weight reduction of components in recent years, as described above, the valve body 52 and the rod 54
When resin or the like is formed into resin, due to the characteristics of the resin material, the sealing portion 55a of the valve seat 56 formed integrally with the valve body 52 and the valve body 55 formed integrally with the rod 54 may be subjected to molding such as inclination and distortion. Inconvenience often occurs. Therefore, in such a case, a gap may be formed on the circumference between the valve seat 56 and the valve body 55 when the valve is closed, and a transfer fluid such as air may leak from the gap.

[0007]

SUMMARY OF THE INVENTION In view of the above, the present invention has been made in consideration of the above-described problems even when a valve seat or a valve body is made of a resin which is liable to cause molding inconveniences such as inclination and distortion. It is an object of the present invention to provide a valve device that does not leak a transfer fluid such as air from the valve and has excellent sealing performance when the valve is closed.

[0008]

In order to achieve the above-mentioned object, a valve device of the present invention is provided with a rubber-made elastic bead provided in a seal portion of a valve body to be in contact with and separated from a valve seat.
The seal lip, which is higher than the bead, is integrally formed on the transfer fluid side of the bead.

In the valve device of the present invention having the above-mentioned structure, the valve made of rubber-like elastic material provided in the seal portion of the valve element is opened and closed by coming into contact with and separating from the valve seat.

Also, since the seal lip, which is higher than the bead, is integrally formed with the bead, the valve seat has inconvenience in forming, such as inclination and distortion, so that the bead may be partially formed on the circumference when the valve is closed. Even if the seal lip cannot contact the valve seat, the seal lip contacts the valve seat following the inclination, distortion, or the like of the valve seat, thereby making it possible to ensure the sealing performance.

Further, since the seal lip is integrally formed on the transfer fluid side of the bead, there is a disadvantage in the formation of the valve seat such as a relatively large inclination and distortion, so that the seal lip has a circumferential shape at the beginning of valve closing. Even if the upper part cannot contact the valve seat, the seal lip is pushed by the pressure of the transfer fluid and contacts the valve seat,
This makes it possible to ensure the sealing performance.

Further, since the bead seated on the valve seat when the valve is closed receives the valve closing load, it is possible to prevent a relatively large load from being applied to the relatively thin seal lip.

[0013]

DESCRIPTION OF THE PREFERRED EMBODIMENTS Next, embodiments of the present invention will be described with reference to the drawings.

FIG. 1 shows a cross section of the valve device according to the embodiment, and FIG. 2 shows an enlarged view of a main part thereof. The valve device is used as an intercooler bypass valve in an intake system of an internal combustion engine such as a vehicle, and is configured as follows.

First, a resin valve body (also referred to as a body or a housing) 2 fixed to an internal combustion engine or the like via a metal bracket 1 having a flat plate shape is provided. A lower cup 2a and an upper cup 2b are provided, and a diaphragm 3 made of a flexible material such as rubber is provided between the body 2a and the upper cup 2b. A diaphragm retainer 4 is disposed below the operating portion of the diaphragm 3, and a spring retainer 5 is also disposed above the operating portion to provide a laminated portion 6 having a three-layer structure. An upper end portion of a resin rod 7 is connected and fixed thereto, and a valve body (also referred to as a valve) 8 is integrally formed at a lower end portion of the rod 7. The valve element 8 will be described later.

An airtight space surrounded by the diaphragm 3 and the upper cup 2b is a negative pressure chamber 9, and a negative pressure is applied to the upper cup 2b so that a negative pressure of the internal combustion engine can be introduced into the negative pressure chamber 9. A pressure port 10 is provided. Further, in the negative pressure chamber 9, a spring retainer 5, a diaphragm 3, a diaphragm retainer 4, a rod 7, and a valve body 8 are provided.
A coil-shaped spring 11 that elastically urges an assembly made of the like downward is disposed.

A bearing 12 for supporting the rod 7 slidably in the axial direction is provided below the laminated portion 6 including the diaphragm 3 and the diaphragm retainer 4 and the like.
Further below the bearing 12, a rod seal 13 having a seal lip 13a slidably in close contact with the peripheral surface of the rod 7 is provided. The bearing 12 and the rod seal 13 are fixed to the stepped portion of the inner wall of the body 2 by means of press fitting, caulking, welding, or the like, with their outer peripheral edges. Diaphragm 3 and rod seal 1
The airtight space between the pressure chamber 3 and the pressure chamber 3 is an atmospheric pressure chamber 14, and an atmospheric pressure port 15 is provided in the body 2 so that the atmospheric pressure can be always introduced into the atmospheric pressure chamber 14.

A valve hole 16 is provided at the lower portion of the body 2 so as to have the same axis as the rod 7, and an intake port 17 is provided below the valve hole 16 so as to be appropriately bent. The valve hole 16 is open at the upper end thereof to a valve chamber 18 inside the body 2, and an exhaust port 19 is provided on a side wall of the valve chamber 18.

The rod 7 is formed in a hollow or cylindrical shape having a tapered end at an upper end thereof, and a flat plate-shaped valve body 8 is integrally formed at the lower end thereof in a flange shape toward the outside in the radial direction. Have been. Reinforcing rib 2 on the upper side of valve body 8
Zeros are provided in a required number of evenly arranged shapes, and the ribs 20 are formed integrally with the rod 7 and the valve body 8, respectively.

A sealing member (also referred to as packing or rubber packing) 21 made of a rubber-like elastic material is attached to the lower surface of the valve body 8 serving as the sealing portion 8a, and a valve seat (valve seat) is provided on the lower surface of the sealing member 21. An annular bead 23 that comes into contact with and separates from the sealing surface 22 is integrally formed, and an annular seal lip (which also comes into contact with and separates from the valve seat 22) is provided on the transfer fluid side, that is, on the inner peripheral side of the bead 23. 24) are integrally formed.

As shown in an enlarged manner in FIG.
Reference numeral 1 denotes a disc-shaped lower surface portion 21a disposed below the rod 7 and the valve body 8, an annular peripheral surface portion 21b integrally formed upward on an outer peripheral end of the lower surface portion 21a, and An annular upper surface portion 21c integrally formed radially inward is integrally provided at an upper end portion of the peripheral surface portion 21b, and is mounted so as to cover the disc-shaped valve body 8 from below. I have.
The bead 23 is formed in a semicircular or arcuate cross section. The seal lip 24 protrudes obliquely inward from the inner peripheral side slope of the bead 23, and the height H from the lower surface of the lower surface 21a in the free state is formed higher than the height h of the bead 23. . The valve seat 22 is integrally formed inside the body 2a.

In the valve device having the above configuration, as shown in the left half of FIG. 1, the spring retainer 5, the diaphragm 3, the diaphragm retainer 4, the rod 7, the valve body 8, and the seal member 21 are initially formed by the elasticity of the spring 11. It is pushed down and positioned at the lower end of the axial displacement, and the bead 23 is seated on the valve seat 22 and the seal lip 24 is in contact with the valve seat 22. Therefore, the valve hole 16 is in a non-communication state, and the valve hole 16 and the valve chamber 1
The flow path 25 that reaches the exhaust port 19 via 8 is closed.

In this closed state, the valve body 2
When a negative pressure whose absolute value is equal to or larger than a predetermined value is introduced into the negative pressure chamber 9 from the negative pressure port 10 provided in the upper case 2b, as shown in the right half of FIG. Spring retainer 5, diaphragm 3, diaphragm retainer 4, rod 7, valve body 8, and seal member 21
Is lifted up against the elasticity of the spring 11 and moves to the upper end of the axial displacement, and the bead 23 and the seal lip 24 are separated from the valve seat 22 respectively. Therefore, valve hole 1
6 is in a communicating state, the flow path 25 is opened, and during this valve opening operation, a part of excessive supply pressure is recirculated. When the absolute value of the negative pressure introduced from the negative pressure port 10 to the negative pressure chamber 9 falls below a predetermined value in this valve open state, the spring retainer 5, the diaphragm 3, the diaphragm retainer 4, the rod 7 , The valve body 8 and the sealing member 21 descend and return to the lower end limit position of the axial displacement, the bead 23 is seated on the valve seat 22 and the seal lip 2
4 comes into contact with the valve seat 22 to close the valve hole 16 and the flow path 25 is closed.

The valve device that operates as described above is characterized in that the above-described configuration has the following functions and effects.

First, a sealing member 21 made of a rubber-like elastic material is attached to the lower surface of the valve body 8 which is the sealing portion 8a, and the bead 2 which comes into contact with and separates from the valve seat 22 is attached to the sealing member 21.
3 is integrally formed, and the seal lip 24, which is higher than the bead 23, is integrally formed on the transfer fluid side, that is, on the inner peripheral side of the bead 23. Bead 23 when closed due to inconvenience
However, even if the seal lip 24 cannot contact the valve seat 22 at various places on the circumference, the seal lip 24 contacts the valve seat 22 following the inclination and distortion of the valve seat 22. Therefore, it is possible to ensure the sealing performance over the entire circumference of the valve seat 22 by this contact,
Thereby, it is possible to prevent the transfer fluid such as air from leaking from between the valve seat 22 and the valve body 8 when the valve is closed.

Further, since the seal lip 24 is integrally formed obliquely inward on the fluid side of the bead 23, that is, on the inner peripheral side, the valve seat 22 has disadvantages in molding such as relatively large inclination and distortion. Therefore, even if the bead 23 and the seal lip 24 cannot contact the valve seat 22 at various places on the circumference at the beginning of the valve closing, the seal lip 24 is pressed by the pressure of the transfer fluid and contacts the valve seat 22. . Therefore, this contact can also ensure the sealing performance over the entire circumference of the valve seat 22, whereby the valve seat 22 and the valve body 8 can be closed when the valve is closed.
It is possible to prevent the transfer fluid such as air from leaking from between.

Further, since the bead 23 seated on the valve seat 22 receives the valve closing load when the valve is closed, it is possible to prevent a relatively large load from being applied to the relatively thin seal lip 24. Therefore, early fatigue of the seal lip 24 due to the valve closing load can be suppressed, and the durability of the seal lip 24 can be improved.

The HNBR rubber is most suitable as the molding material for the rubber-like elastic sealing member 21 because of its excellent gasoline resistance and low adhesion to resin.

[0029]

The present invention has the following effects.

First, in the valve device of the present invention having the above-described structure, a rubber-made elastic material bead is provided at the seal portion of the valve body so as to be in contact with and separate from the valve seat. In addition, since the seal lip, which is higher than the bead, is molded integrally, the resin valve seat has inconveniences in molding, such as tilting and distortion, and when the valve is closed, the bead may be located on the circumference of the valve seat. Even if the seal lip cannot contact the valve seat, the seal lip can contact the valve seat following the inclination or distortion of the valve seat. Therefore, the sealing property can be ensured over the entire circumference of the valve seat by this contact, whereby leakage of the transfer fluid such as air from between the valve seat and the valve body when the valve is closed can be prevented.

Further, since the seal lip is integrally formed on the transfer fluid side of the bead, there is a disadvantage in the formation of the valve seat such as a relatively large inclination and distortion, so that the seal lip is formed on the circumference at the beginning of valve closing. The seal lip can be pressed by the pressure of the transfer fluid and contact the valve seat even if the valve seat cannot be contacted at some places. Therefore, this contact can also ensure the sealing performance over the entire circumference of the valve seat, thereby preventing leakage of a transfer fluid such as air from between the valve seat and the valve body when the valve is closed. .

Further, since the bead seated on the valve seat receives the valve closing load when the valve is closed, it is possible to prevent a large load from being applied to the relatively thin seal lip. Therefore, early fatigue of the seal lip due to the valve closing load can be suppressed, and the durability of the seal lip can be improved.

[Brief description of the drawings]

FIG. 1 is a sectional view of a valve device according to an embodiment of the present invention.

FIG. 2 is an enlarged view of a main part of FIG. 1;

FIG. 3 is a cross-sectional view of a conventional valve device.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Bracket 2 Valve body 2a Body main body 2b Upper cup 3 Diaphragm 4 Diaphragm retainer 5 Spring retainer 6 Stacking part 7 Rod 8 Valve body 8a Seal part 9 Negative pressure chamber 10 Negative pressure port 11 Spring 12 Bearing 13 Rod seal 13a, 24 Seal lip 14 Atmospheric pressure chamber 15 Atmospheric pressure port 16 Valve hole 17 Intake port 18 Valve chamber 19 Exhaust port 20 Rib 21 Seal member 21a Lower surface portion 21b Peripheral surface portion 21c Upper surface portion 22 Valve seat 23 Bead 25 Flow path

Claims (1)

[Claims] A bead (23) made of a rubber-like elastic material which comes into contact with and separates from a valve seat (22) is provided on a seal portion (8a) of a valve body (8) and has a height higher than the bead (23). A valve device, characterized in that a high sealing lip (24) is integrally formed on the transfer fluid side of the bead (23).