US3840280A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Compensation valve device for a load sensing valve
Assignee: Akebono Brake Industry Co Ltd
•
Filing: 1973-04-05
•
Granted: 1974-10-08
•
Expires: 1993-04-05
Abstract
Abstract In a load sensing valve installed between a master cylinder and rear wheel brakes of a motor vehicle, having first and second fluid chambers connected respectively to the master cylinder and to the rear wheel brakes, a compensating valve device is provided in a bypass arranged between the first and second fluid chambers. A load sensing lever of the load sensing valve is connected to a compensating valve lever of the compensating valve device through a load spring. The compensating valve lever presses a compensating valve piston of the compensating valve device under the force of the load spring in such a manner as to normally close the valve of the compensating valve device. In the event of breakage in the load spring or lever and pin mechanism connected thereto, causing the loss of the spring force or a decrease thereof to a degree lower than a certain value, the valve of the compensating valve device is opened by the fluid pressures of the first and second fluid chambers provided in the compensating valve device, so that the fluid pressure from the master cylinder can be supplied to the rear wheel brakes through the compensating valve device.
Inventors
- 👤 N Watanabe
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-29 05:56
CPC Classifications
B; B60; B60T; B60T8/00; B60T8/18; B60T8/1837; B60T8/185
Claims Analysis
Total Claims: 8
Claim 1
Independent Claim
354 words
In a load sensing valve device for the rear brakes of a vehicle having a body and axles including at least one rear axle, the load sensing valve device including a cylinder fixed to the vehicle body and having a first valve chamber for connection to a source of brake fluid subjected to pressure and a second valve chamber for connection to the rear brakes, a sensing valve piston axially displaceable in the cylinder in a valving portion thereof and regulating the flow of fluid between the first and second valve chambers, a load sensing lever pivoted intermediate its ends to the vehicle body and engaged with a head of the sensing valve piston, an operating spring connecting one end of the sensing lever to a rear axle, a load spring connected to the other end of the sensing lever, and means connecting the load spring to the vehicle body, and a normally closed compensating valve device communicating with both valve chambers and operable, responsive to breakage of any one of the operating spring, the sensing lever and the load spring, to establish communication between the two valve chambers; an improved compensating valve device comprising, in combination, a second cylinder having respective ports communicating with said first and second valve chambers; a valve mechanism in said second cylinder between said ports and including a compensating valve piston axially displaceable in said second cylinder; and a compensating valve lever, independent of said load sensing lever, pivotally connected at one end to said vehicle body and having its opposite free end connected to said load spring; said compensating valve lever having an intermediate portion engaging said compensating valve piston and, under the bias of said load spring, maintaining said valve mechanism closed to block flow between said ports; said compensating valve lever, responsive to breakage of any one of said operating spring, said sensing lever and said load spring, releasing said compensating valve piston for opening of said valve mechanism to establish a by-pass flow path between said first and second valve chambers and completely independent of said valving portion of said sensing valve device cylinder.
Claim 2
Dependent Claim
354 words
In a load sensing valve device for the rear brakes of a vehicle having a body and axles including at least one rear axle, the load sensing valve device including a cylinder fixed to the vehicle body and having a first valve chamber for connection to a source of brake fluid subjected to pressure and a second valve chamber for connection to the rear brakes, a sensing valve piston axially displaceable in the cylinder in a valving portion thereof and regulating the flow of fluid between the first and second valve chambers, a load sensing lever pivoted intermediate its ends to the vehicle body and engaged with a head of the sensing valve piston, an operating spring connecting one end of the sensing lever to a rear axle, a load spring connected to the other end of the sensing lever, and means connecting the load spring to the vehicle body, and a normally closed compensating valve device communicating with both valve chambers and operable, responsive to breakage of any one of the operating spring, the sensing lever and the load spring, to establish communication between the two valve chambers; an improved compensating valve device comprising, in combination, a second cylinder having respective ports communicating with said first and second valve chambers; a valve mechanism in said second cylinder between said ports and including a compensating valve piston axially displaceable in said second cylinder; and a compensating valve lever, independent of said load sensing lever, pivotally connected at one end to said vehicle body and having its opposite free end connected to said load spring; said compensating valve lever having an intermediate portion engaging said compensating valve piston and, under the bias of said load spring, maintaining said valve mechanism closed to block flow between said ports; said compensating valve lever, responsive to breakage of any one of said operating spring, said sensing lever and said load spring, releasing said compensating valve piston for opening of said valve mechanism to establish a by-pass flow path between said first and second valve chambers and completely independent of said valving portion of said sensing valve device cylinder.
Claim 3
Dependent Claim
103 words
An improved compensating valve device, as claimed in claim 1, in which said load sensing valve cylinder and said second cylinder are mounted in parallel on said vehicle body; said head of said sensing valve piston extending in a direction opposite from the portion of said compensating valve piston engaged by said compensating valve lever, whereby said load sensing lever and said compensating valve lever are arranged at opposite ends of the assembly of said sensing valve cylinder and said second cylinder; said load spring interconnecting said other end of said sensing lever and said opposite free end of said compensating valve lever.
Claim 4
Dependent Claim
114 words
An improved compensating valve device, as claimed in claim 1, including a plug inserted into said second cylinder and defining a third fluid chamber, said plug having an axial passage therein communicating with said third fluid chamber; saiD compensating valve piston being inserted in the opposite end of said second cylinder to project therefrom for engagement by said compensating valve lever; said compensating valve piston supporting a ball blocking said passage in said plug; said ball being disposed in a fourth fluid chamber defined by said second cylinder and said compensating valve piston; said third fluid chamber communicating with said first valve chamber and said fourth fluid chamber communicating with said second valve chamber.
Claim 5
Dependent Claim
69 words
An improved compensating valve device, as claimed in claim 3, in which said second cylinder has a large diameter portion and a small diameter portion; said plug being threaded into said large diameter portion; said compensating valve piston having a flange thereon engageable with a shoulder between said large diameter portion and said small diameter portion of said second cylinder, to limit outward movement of said compensating valve piston.
Claim 6
Dependent Claim
40 words
An improved compensating valve device, as claimed in claim 3, in which said passage in said plug terminates in a valve seat; the end of said compensating valve piston facing said plug being formed with a recess receiving said ball.
Claim 7
Dependent Claim
44 words
An improved compensating valve device, as claimed in claim 3, including a body formed with a first passage connecting said third fluid chamber to said first valve chamber and formed with a second passage connecting said fourth fluid chamber to said second valve passage.
Claim 8
Dependent Claim
53 words
An improved compensating valve device, as claimed in claim 3, in which, when said compensating valve piston is released by said compensating valve lever, said ball and said compensating valve piston are moved in a valve mechanism opening direction by the difference in the fluid pressure of said third and fourth fluid chambers.
References Cited (Backward Citations)
No citation records indexed.
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1977-10-07 | 1978-04-08 | 1978-10-08 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1981-10-07 | 1982-04-08 | 1982-10-08 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1985-10-07 | 1986-04-08 | 1986-10-08 | $7700.00 | Window Closed / Lapsed |