US3837712A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Anti-locking braking device
Assignee: Automobiles Citroen SA
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Filing: 1973-07-19
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Granted: 1974-09-24
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Expires: 1993-07-19
Abstract
Abstract An anti-locking braking device for a wheel of a motor vehicle for reducing jerky braking, wherein a fluid operated brake cylinder is connectable, when the wheel is about to lock, to a fluid outlet comprising first and second flow paths leading to a reservoir. In the first flow path a restriction is provided downstream of a first chamber whose volume is increased by movement therein of a spring biased first piston under the effect of pressure of the fluid admitted to the chamber. Such movement is arranged to open a first valve in the second flow path, and fluid form the brake cylinder to the reservoir can by-pass the restriction and thus a faster rate of pressure drop in the brake cylinder can be achieved, provided a second valve, also in the second flow path is open. Movement of this second piston controls opening and closing of the second flow path by the second valve which is open when fluid pressure in the first flow path upstream of the restriction exerts a lower force on one side of the second piston than the force exerted on the other side by a spring.
Inventors
- 👤 A Grosseau
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-04 06:59
CPC Classifications
B; B60; B60T; B60T8/00; B60T8/32; B60T8/34; B60T8/341
Claims Analysis
Total Claims: 4
Claim 1
Independent Claim
233 words
Anti-locking braking device for a wheel of a motor vehicle, comprising a source of fluid under pressure controlled by the driver, receiving means coupled to the brake of said wheel, a valve controlled by a control device detecting the dynamic state of the wheel and able to connect the receiving means selectively to the source of fluid under pressure and to a first conduit means connected to a fluid reservoir, a flow-limiter being disposed in said first conduit means and an elastically variable member, provided, in particular, with a moving part, being interposed in said first conduit means between the controlled valve and said flow-limiter, characterised by a second conduit means branched from the first conduit means between the controlled valve and the flow-limiter and connected to said fluid reservoir, said second conduits means includes closure means coupled to the moving part of the elastically variable member which is in a position for opening said second conduit means when the volume of fluid in the elastically variable member is at a maximum and wherein said second conduit means comprises a valve member controlled by the pressure prevailing in said first conduit means between the controlled valve and the flow-limiter which is indicative of the pressure prevailing in the braking receiving members and which is in a position for closing said second conduit means when the control pressure is greater than a pre-determined value.
Claim 2
Dependent Claim
233 words
Anti-locking braking device for a wheel of a motor vehicle, comprising a source of fluid under pressure controlled by the driver, receiving means coupled to the brake of said wheel, a valve controlled by a control device detecting the dynamic state of the wheel and able to connect the receiving means selectively to the source of fluid under pressure and to a first conduit means connected to a fluid reservoir, a flow-limiter being disposed in said first conduit means and an elastically variable member, provided, in particular, with a moving part, being interposed in said first conduit means between the controlled valve and said flow-limiter, characterised by a second conduit means branched from the first conduit means between the controlled valve and the flow-limiter and connected to said fluid reservoir, said second conduits means includes closure means coupled to the moving part of the elastically variable member which is in a position for opening said second conduit means when the volume of fluid in the elastically variable member is at a maximum and wherein said second conduit means comprises a valve member controlled by the pressure prevailing in said first conduit means between the controlled valve and the flow-limiter which is indicative of the pressure prevailing in the braking receiving members and which is in a position for closing said second conduit means when the control pressure is greater than a pre-determined value.
Claim 3
Dependent Claim
117 words
Braking device according to claim 1, characterised in that the first and second conduits means are joined by means of the elastically variable member, wherein the said closure means is constituted by the moving part of the elastically variable member formed as a piston mounted to slide in a cylindrical and hollow rigid body to which the second conduit means is connected, said piston being provided with inner chaNnels which, when the volume of fluid in the elastically variable member is at a maximum, are able to connect said second conduit means to a chamber defined by said piston in said body with the first conduit means at a point between the controlled valve and the flow-limiter.
Claim 4
Dependent Claim
109 words
Braking device according to claim 1, characterised in that said valve member is constituted by a cylindrical hollow body in which a slidably mounted closure piston defines a first chamber connected to the chamber of the elastically variable member, and a second chamber connected to said reservoir to which the second conduit means is connected and wherein an elastic member is provided between said piston and said body and tends to maintain the piston in a position opening the second conduit means by keeping the volume of fluid in the first chamber minimal such that the piston uncovers an aperture connecting the second conduit means to the second chamber.
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) | 1977-09-23 | 1978-03-25 | 1978-09-24 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1981-09-23 | 1982-03-25 | 1982-09-24 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1985-09-23 | 1986-03-25 | 1986-09-24 | $7700.00 | Window Closed / Lapsed |