US3871716A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Anti-lock vehicle brake systems
Assignee: US Philips Corp
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Filing: 1973-05-30
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Granted: 1975-03-18
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Expires: 1993-05-30
Abstract
Abstract An anti-lock brake system including fluid flow apparatus including a flow measuring piston having a flow restrictor limiting flow of fluid from one side of the piston to the other side. One side thereof is exposed to inlet pressure and one side to outlet pressure. A spring biases the piston in one direction and a separate spring is provided to bias the piston in the opposite direction.
Inventors
- 👤 Derek Robert Skoyles
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-06 17:28
CPC Classifications
F; F15; F15B; F15B11/00; F15B11/02; B; B60; B60T; B60T8/00; B60T8/32; B60T8/34; B60T8/341; B60T8/50; B60T8/5018; B60T8/5025; B60T8/5037; B60T8/58; F15B7/00; F15B7/06; F15B2211/00; F15B2211/40; F15B2211/405; F15B2211/40507; F15B2211/40515; F15B2211/42; F15B2211/426; F15B2211/45; F15B2211/50; F15B2211/505; F15B2211/50563; F15B2211/50572; F15B2211/52; F15B2211/528; F15B2211/60; F15B2211/605; F15B2211/6051; F15B2211/63; F15B2211/6303; F15B2211/665; F15B2211/6654; F15B2211/70; F15B2211/705; F15B2211/7051; F15B2211/7052; F15B2211/76
Claims Analysis
Total Claims: 14
Claim 1
Independent Claim
239 words
Fluid flow control apparatus comprising a housing having inlet and outlet ports, a metering orifice having a first side in fluid communication with said inlet port and a second axially spaced side in fluid communication with said outlet Port, a flowmeasuring piston carried by said housing for axial movement, with said piston having a first side in fluid communication with said inlet port and a second side in fluid communication with said outlet port, said piston modulating fluid flow upon axial movement thereof and shutting off all flow to said outlet in one axial position fluid outlet pressure never being more than the fluid inlet pressure and the fluid pressure difference across said piston providing a force tending to axially displace said flow-measuring piston into said one axial position, a fluid pressure equalizing path for applying fluid pressure at said outlet port to an equalizing area at the side of said flowmeasuring piston remote from said outlet port which equalizing area is isolated from fluid pressure at said inlet port, spring means providing a force tending to displace said flow-measuring piston away from said outlet port in opposition to the force due to said fluid pressure difference, means for axially biasing said flow-measuring piston opposite to said spring means, said apparatus controlling the flow rate of fluid into said outlet port as a function of the force of said spring means and the cross-sectional area of said metering orifice.
Claim 2
Dependent Claim
239 words
Fluid flow control apparatus comprising a housing having inlet and outlet ports, a metering orifice having a first side in fluid communication with said inlet port and a second axially spaced side in fluid communication with said outlet Port, a flowmeasuring piston carried by said housing for axial movement, with said piston having a first side in fluid communication with said inlet port and a second side in fluid communication with said outlet port, said piston modulating fluid flow upon axial movement thereof and shutting off all flow to said outlet in one axial position fluid outlet pressure never being more than the fluid inlet pressure and the fluid pressure difference across said piston providing a force tending to axially displace said flow-measuring piston into said one axial position, a fluid pressure equalizing path for applying fluid pressure at said outlet port to an equalizing area at the side of said flowmeasuring piston remote from said outlet port which equalizing area is isolated from fluid pressure at said inlet port, spring means providing a force tending to displace said flow-measuring piston away from said outlet port in opposition to the force due to said fluid pressure difference, means for axially biasing said flow-measuring piston opposite to said spring means, said apparatus controlling the flow rate of fluid into said outlet port as a function of the force of said spring means and the cross-sectional area of said metering orifice.
Claim 3
Dependent Claim
15 words
Apparatus as claimed in claim 1, wherein said metering orifice is a sharp edged orifice.
Claim 4
Dependent Claim
22 words
Apparatus as claimed in claim 1 wherein said metering orifice is an aperture which extends through the width of the flow-measuring piston.
Claim 5
Dependent Claim
42 words
Apparatus as claimed in claim 1 wherein said metering orifice is provided in a by-pass connection which forms part of the fluid path and which communicates with a chamber in which the flow-measuring piston is accommodated at opposite sides of the latter.
Claim 6
Dependent Claim
34 words
Apparatus as claimed in claim 4, wherein said equalizing area at the side of the flow-measuring piston remote from said outlet port is the same size as the cross-sectional area of the outlet port.
Claim 7
Dependent Claim
34 words
Apparatus as claimed in claim 1 wherein said equalizing area at the side of the flow-measuring piston remote from said outlet port is of greater size than the cross-sectional area of the outlet port.
Claim 8
Dependent Claim
37 words
Apparatus as claimed in claim 6, including a second displaceable piston which is carried for displacement by a volume of fluid to reduce the force exerted by the spring means as a function of the displacement thereof.
Claim 9
Dependent Claim
57 words
Apparatus as claimed in claim 7, said spring means comprises a first spring applying to the flow measuring piston a force in one direction a second spring which opposes the force due to said fluid pressure difference, and said first spring, said second piston upon displacement in one direction increasing the force exerted by said first spring.
Claim 10
Dependent Claim
20 words
Apparatus as claimed in claim 8 wherein the fluid pressure equalizing path comprises an orifice extending through the flow-measuring piston.
Claim 11
Dependent Claim
116 words
Apparatus as claimed in claim 9, including a sealing and balancing member which is located at the side of the flow-measuring piston remote from said outlet port and has a seal bounding the orifice at that side, an aperture communicating with said orifice within the seal boundary and an equalizing area bounding said aperture said sealing and balancing member at the onset of flow of fluid through said housing being separated from the flow-measuring piston to permit fluid flow through said orifice between the inlet and outlet ports, and means for urging said member into engagement with the flow-measuring piston, so that the orifice is sealed by said seal, at the onset of fluid flow control.
Claim 12
Dependent Claim
38 words
Apparatus as claimed in claim 10, wherein said member has a seal that bounds the predominant portion of the side of the flow-measuring piston remote from the outlet port, said predominant portion not including the metering orifice aperture.
Claim 13
Dependent Claim
62 words
An anti-lock vehicle brake system having a fluid flow control apparatus as claimed in claim 11, further including a fluid pressure source and a wheel brake controlled by the system each in fluid communicAtion with said apparatus, and a solenoid valve said means for biasing said flow measuring piston being responsive to the volume of fluid passing through said a solenoid valve.
Claim 14
Dependent Claim
81 words
The apparatus as described in claim 1 wherein said means for axially biasing said flow-measuring piston comprises a bias piston carried in said housing, said bias piston being axially movable in a direction generally aligned with the axis of said flow-measuring piston, said means for axially biasing further including a spring coupling said bias piston and said flow-measuring piston, and said means for axially biasing said flow-measuring piston urging said flow-measuring piston towards said outlet port in one axial position thereof.
References Cited (Backward Citations)
US3724914A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1978-03-17 | 1978-09-16 | 1979-03-18 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1982-03-17 | 1982-09-16 | 1983-03-18 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1986-03-17 | 1986-09-16 | 1987-03-18 | $7700.00 | Window Closed / Lapsed |