US3729236A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Anti-skid brake control arrangement for vehicle wheels
Assignee: Aisin Corp
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Filing: 1969-05-16
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Granted: 1973-04-24
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Expires: 1989-05-16
Abstract
Abstract This invention relates to a hydraulic pressure control valve arrangement for automotive vehicle wheel brake systems, the latter system comprising a hydraulic master cylinder to be actuated by operating a foot brake pedal; a hydraulic brake pressure control valve assembly provided with a pneumatic servo piston means; and electromagnetic change-over valve assembly fluidically connected therewith; a skid sensor operatively connected therewith and also with a vehicle wheel; and wheel cylinder means for applying hydraulic braking effort upon vehicle wheels. The improvement comprises the provision of a control valve of orifice type in said hydraulic brake pressure control valve assembly, for bringing the working stroke of said servo piston to realize in a rapid way during reduction of the effective volume of the hydraulic circuit leading from said pressure control valve assembly to wheel cylinder means in case of an overbrake application, and until a certain stage of said working stroke, and then carrying about the latter in a highly slow and continuous way.
Inventors
- 👤 T Okamoto
- 👤 M Inada
- 👤 K Takayama
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-26 21:25
CPC Classifications
B; B60; B60T; B60T8/00; B60T8/32; B60T8/34; B60T8/42; B60T8/4208; B60T8/4225; B60T8/4241; B60T8/425
Claims Analysis
Total Claims: 3
Claim 1
Independent Claim
415 words
An anti-skid brake control system for a plurality of wheels of a wheeled vehicle having brakes actuatable from a fluid source of pressure comprising a control valve assembly locatable in a hydraulic circuit between a hydraulic master cylinder and cylinder means for said wheels, said control valve assembly comprising a diaphragm piston movable within a cylinder and defining two pneumatic fluid chambers therein, an on-off control valve located in said hydraulic circuit for interrupting normal hydraulic communication between said master cylinder and said wheel cylinder means, hydraulic pressure reducing valve means located in said control valve assembly and adapted to move so as to increase the effective volume of said hydraulic circuit on the wheel cylinder side of said on-off control valve means, said onoff control valve means and said pressure reducing valve means normally being disposed in an inoperative position by said diaphragm piston, passage means providing communication between said pneumatic fluid chambers, electromagnetic device means operably located in said passage means and normally allowing communication between said two pneumatic fluid chambers, sensor means adapted for sensing a locked condition of at least one of said wheels upon sudden brake application, said electromagnetic valve means being responsive to said sensor upon detecting a locked condition to close communication between said two pneumatic chambers and admit ambient air to one of said chambers, connecting means adapted to connect the other of said chambers to a source of negative pressure, fluid flow control means located in said passage means, said flow control means being movable independently of said diaphragm piston between a first position allowing a relatively rapid flow of fluid through said passage means and a second position allowing a relatively restricted flow of fluid through said passage means whereby upon detection of a locked wheel condition ambient air will be admitted to said one of said chambers to move said diaphragm piston allowing hydraulic pressure from said master cylinder to close said on-off valve means and move said pressure reducing valve means to allow reduction of pressure in said wheel cylinders and upon sensing the unlocked condition of said wheel restoring communication between said chambers thereby moving said flow control means to said first position until the pressure differential between said chambers reaches a predetermined point whereupon said flow control means will move to said second position to allow a restricted flow of fluid to provide for a gradual movement of said diaphragm piston and a gradual build-up of pressure in said wheel cylinders.
Claim 2
Dependent Claim
415 words
An anti-skid brake control system for a plurality of wheels of a wheeled vehicle having brakes actuatable from a fluid source of pressure comprising a control valve assembly locatable in a hydraulic circuit between a hydraulic master cylinder and cylinder means for said wheels, said control valve assembly comprising a diaphragm piston movable within a cylinder and defining two pneumatic fluid chambers therein, an on-off control valve located in said hydraulic circuit for interrupting normal hydraulic communication between said master cylinder and said wheel cylinder means, hydraulic pressure reducing valve means located in said control valve assembly and adapted to move so as to increase the effective volume of said hydraulic circuit on the wheel cylinder side of said on-off control valve means, said onoff control valve means and said pressure reducing valve means normally being disposed in an inoperative position by said diaphragm piston, passage means providing communication between said pneumatic fluid chambers, electromagnetic device means operably located in said passage means and normally allowing communication between said two pneumatic fluid chambers, sensor means adapted for sensing a locked condition of at least one of said wheels upon sudden brake application, said electromagnetic valve means being responsive to said sensor upon detecting a locked condition to close communication between said two pneumatic chambers and admit ambient air to one of said chambers, connecting means adapted to connect the other of said chambers to a source of negative pressure, fluid flow control means located in said passage means, said flow control means being movable independently of said diaphragm piston between a first position allowing a relatively rapid flow of fluid through said passage means and a second position allowing a relatively restricted flow of fluid through said passage means whereby upon detection of a locked wheel condition ambient air will be admitted to said one of said chambers to move said diaphragm piston allowing hydraulic pressure from said master cylinder to close said on-off valve means and move said pressure reducing valve means to allow reduction of pressure in said wheel cylinders and upon sensing the unlocked condition of said wheel restoring communication between said chambers thereby moving said flow control means to said first position until the pressure differential between said chambers reaches a predetermined point whereupon said flow control means will move to said second position to allow a restricted flow of fluid to provide for a gradual movement of said diaphragm piston and a gradual build-up of pressure in said wheel cylinders.
Claim 3
Dependent Claim
43 words
An anti-skid brake control system as set forth in claim 1, wherein said flow control means is comprised of a one-way check valve having a valve member with a restricted orifice therethrough and spring means urging said valve member to said second position.
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) | 1976-04-23 | 1976-10-23 | 1977-04-24 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1980-04-23 | 1980-10-23 | 1981-04-24 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1984-04-23 | 1984-10-23 | 1985-04-24 | $7700.00 | Window Closed / Lapsed |