Vacuum check valve

• US 4,951,708 A
• Filed: 11/30/1988
• Issued: 08/28/1990
• Est. Priority Date: 11/30/1988
• Status: Expired due to Term

• Current Assignee: General Motors Corporation (General Motors Company)
• Original Assignee: General Motors Corporation (General Motors Company)
• Inventors: Miller, James W.
• Primary Examiner(s): Nilson, Robert G.
• Application Number:
  US07/277,629
• Time in Patent Office: 636 Days
• Field of Search: 137/526, 137/533.25, 137/542, 137/543
• US Class Current: 137/526
• CPC Class Codes: B60T 17/008 Silencer devices
• CPC Class Codes: B60T 17/04 Arrangements of piping, valves in the piping, e.g. cut-off valves, couplings or air hoses traction couplings involving joints for supply lines, electric circuits, or the like B60D1/62; couplings peculiar to railway vehicles for, or combined with, couplings or connectors for fluid conduits or electric cables B61G5/06; pipes, cut-off valves, couplings, air hoses per se F16C, F16K, F16L
• CPC Class Codes: F16K 15/063 the valve being loaded by a spring
• CPC Class Codes: Y10T 137/7897 Vacuum relief type
• CPC Class Codes: Y10T 137/7932 Valve stem extends through fixed spring abutment

Abstract

Resilient accommodation of vacuum brake booster check valves to vacuum source-generated pressure pulses tending to cause the valves to pulse open and close is accomplished by providing a resilient annular area in the check valve radially between its axial center and the area where it sealingly engages a valve seat when closed to inhibit valve pulsations and resulting valve noises generated by pulsations from the vacuum source.

Claims

1. In a vacuum check valve assembly for a vacuum powered brake booster having:

a housing having a valve chamber formed therein, an inlet opening adapted to be connected to a vacuum powered brake booster, an outlet opening adapted to be connected to a source of vacuum pressure;

a check valve in said valve chamber having a normal closed position preventing vacuum communication between said outlet and said inlet and an open position permitting vacuum communication between said outlet and said inlet;

said check valve having an axially guided center disc including a disc body having a center and an annular rubberlike valve portion on the outer peripheral part of said disc body which sealingly engages said housing when said valve is in the normal closed position and is spaced from said housing to permit air to flow therepast when said valve is in the open position;

the improvement comprising;

said check valve center disc having a flexible portion of said disc body radially intermediate the area of sealing engagement of said center disc annular rubberlike valve portion with said housing and said center of said disc body, said flexible portion being formed by an annular less thick portion of said disc body than the part of said disc body radially inward of said flexible portion, said flexible portion acting when said valve is in said normal closed position to permit slight axial movements of said disc body in response to pressure pulsations generated by said source of vacuum pressure without unsealing said rubberlike valve portion from said housing.

2. In a check valve for a vacuum powered brake booster having:

a housing having a valve chamber formed therein, an inlet opening adapted to be connected to a vacuum powered brake booster, an outlet opening adapted to be connected to a source of vacuum pressure, and a check valve assembly in said valve chamber having a normally closed position preventing vacuum communication between said outlet opening and said inlet opening and an open position permitting vacuum communication between said outlet opening and said inlet opening;

said valve having a center disc and an annular rubberlike valve portion which sealingly engages said housing when said valve is in the normally closed position and is spaced from said housing to permit air to flow therepast when said valve is in the open position;

the improvement comprising;

said valve center disc having a thinner section positioned radially between the disc center and the disc periphery, said thinner section providing a spring-like action at a lower force level than would be the case if said valve center disc were of substantially constant thickness from the disc center to the disc periphery.

3. In a vacuum check valve assembly for controlling vacuum fluid pressure in a container, said check valve assembly having:

a housing;

a valve chamber in said housing defined by opposed end walls and a side wall formed as a part of said housing;

an inlet port and an outlet port formed in said housing and respectively opening through different ones of said walls so as to be in fluid communication with said valve chamber, said inlet port being adapted to be connected to a container in which vacuum fluid pressure is to be normally retained and said outlet port being adapted to be connected to a source of vacuum fluid pressure;

an annular valve seat formed as a part of one of said housing end walls about said inlet port;

a valve member movably mounted in said valve chamber and having a disc-like valve element in radially inwardly spaced relation to said chamber side wall, said valve member disc-like valve element having an annular peripheral portion, an inner portion, a valve element center, and a rubberlike valve portion secured on the annular peripheral portion;

said valve member further having valve stem means extending axially from said disc-like valve element;

said housing having valve stem-receiving guide means formed in said opposed end walls limiting the movements of said valve member to movements axially of said valve stem means and said disc-like valve element and toward and away from said annular valve seat to close said inlet port in one position and to open said inlet port and permit fluid flow around said disc-like valve element through said valve chamber and into said outlet port;

and a valve spring axially biasing said valve member toward said annular valve seat;

the improvement comprising;

said valve member disc-like valve element having at least one section positioned radially between the outer periphery of said annular peripheral portion and said valve element center and positioned in radially outward spaced relation to said valve element center, said at least one section being substantially thinner in thickness than the thickness of said valve element between said valve element center and said section, said at least one thinner section providing a spring-like action at a lower force level than would be the case if said valve element were of substantially constant thickness from said center to the outer periphery of said annular peripheral portion.

4. The invention of claim 3 in which said at least one thinner section extends to the outer periphery of said annular peripheral portion.

5. The invention of claim 3 in which said at least one thinner section is located radially inward of said rubberlike valve portion.

6. The invention of claim 3 in which said at least one thinner section comprises a series of radially spaced grooves located on at least one side of said valve element.

7. The invention of claim 6 in which said grooves are concentric grooves.

8. The invention of claim 6 in which said grooves are formed by at least one spiral groove.

9. The invention of claim 6 in which said grooves are located on both sides of said valve element.

10. The invention of claim 9 in which said grooves on one side of said valve element are aligned with said grooves o the other side of said valve element so that the thinner sections are defined by the disc element material between the bottoms of said grooves.