Patent US4242172A successfully refreshed from Google Patents.
US3680922A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Hydraulic braking pressure control system having valve responsible to the oil pressure deviation for vehicles
Assignee: ZF Active Safety US Inc
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Filing: 1970-01-26
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Granted: 1972-08-01
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Expires: 1990-01-26
Abstract
Abstract The brake control device functions initially in the ordinary manner to first apply the same pressure to the brake cylinders of the front and rear wheels and thereafter to provide a slower rise in pressure to the rear wheel brake cylinders as the pressure on the front brake cylinders increases. Thereafter, there will be no further increase in pressure applied to the rear wheel brake cylinders as further pressure is applied to the front wheel brake cylinders and the brake control device.
Inventors
- 👤 Shinji Kawai
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-05 06:24
CPC Classifications
B; B60; B60T; B60T8/00; B60T8/26; Y; Y10; Y10T; Y10T137/00; Y10T137/7722; Y10T137/7771; Y10T137/7772; Y10T137/7774; Y10T137/7775; Y10T137/7781; Y10T137/7834
Claims Analysis
Total Claims: 6
Claim 1
Independent Claim
151 words
In a hydraulic braking pressure control system for a vehicle, a body having an inlet and an outlet to a hollow interior, a reciprocal piston in said hollow interior having a valve seat therewithin, sealing means of different diameters on opposite ends of the piston straddling said inlet opening, a reciprocal valve means within the piston movable into and out of engagement with said valve seat, spring means of different strength engaging opposite ends of said valve means for exerting different forces thereon, and a spring at one end of the piston for urging the piston toward the outlet end of the hollow interior into engagement with the end of the body to separate the seat from the valve means under related pressure conditions at the inlet and outlet openings to increase the pressure at the outlet opening at a slower rate than the pressure is increased at the inlet opening.
Claim 2
Dependent Claim
151 words
In a hydraulic braking pressure control system for a vehicle, a body having an inlet and an outlet to a hollow interior, a reciprocal piston in said hollow interior having a valve seat therewithin, sealing means of different diameters on opposite ends of the piston straddling said inlet opening, a reciprocal valve means within the piston movable into and out of engagement with said valve seat, spring means of different strength engaging opposite ends of said valve means for exerting different forces thereon, and a spring at one end of the piston for urging the piston toward the outlet end of the hollow interior into engagement with the end of the body to separate the seat from the valve means under related pressure conditions at the inlet and outlet openings to increase the pressure at the outlet opening at a slower rate than the pressure is increased at the inlet opening.
Claim 3
Dependent Claim
42 words
In a hydraulic braking pressure control system as recited in claim 1, wherein the pressure at the inlet opening is applied to the front wheel brake cylinders and the pressure at the outlet opening is applied to the rear wheel brake cylinders.
Claim 4
Dependent Claim
66 words
In a hydraulic braking pressure control system as recited in claim 2, wherein the further increase of pressure at the inlet opening produces a movement of the piston and valve means and the separation of the latter from the piston valve seat to increase the flow of fluid and pressure at the outlet opening which thereupon produces the seating of the valve on the valve seat.
Claim 5
Dependent Claim
39 words
In a hydraulic braking pressure control system as recited in claim 3, wherein the pressure delivered to the rear wheel brake cylinders progressively decreases as the pressure on the front wheel brake cylinders is increased to a predetermined pressure.
Claim 6
Dependent Claim
81 words
In a hydraulic braking pressure control system as recited in claim 4, wherein the relationship of the strength of the springs acting on opposite ends of the valve means in the presence of further increase of pressure beyond said predetermined pressure at the inlet opening will produce the seating of the valve means on the valve seat for the remainder of the time that the pressure at the inlet opening increases without increasing the pressure on the rear wheel brake cylinders.
References Cited (Backward Citations)
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1975-08-01 | 1976-01-31 | 1976-08-01 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1979-08-01 | 1980-01-31 | 1980-08-01 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1983-08-01 | 1984-01-31 | 1984-08-01 | $7700.00 | Window Closed / Lapsed |