US3792908A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Fluid pressure control valve
Assignee: Dunlop Holdings Ltd
•
Filing: 1971-09-22
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Granted: 1974-02-19
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Expires: 1991-09-22
Abstract
Abstract A fluid pressure control valve for maintaining the fluid pressure supplied to an associated fluid pressure operated device at or as near a selected value as the operating conditions of the associated fluid pressure operated device indicate to be appropriate. The valve comprises a housing incorporating a spindle axially displaceable in a spindle chamber against spring means by the selected pressure, the spring means being arranged to act between the spindle and a movable abutment. The arrangement of the spindle is such that at any given moment the level of fluid pressure supplied to the associated device by the valve is proportional to the spring force exerted on the spindle by the spring means at that moment, this spring force being normally proportional to the selected pressure thus ensuring that the selected pressure is supplied to the associated device. The spring force is also variable in response to movement of the movable abutment, resulting from a change in the operating conditions of the associated device necessitating a change in the pressure applied to the fluid pressure operated device, under the control of valve means, of which the following is a specification.
Inventors
- 👤 A Brewster
- 👤 S Harvey
- 👤 F Mortimer
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-23 21:27
CPC Classifications
B; B60; B60T; B60T8/00; B60T8/32; B60T8/34; B60T8/50; B60T8/5056; F; F15; F15B; F15B11/00; F15B11/02; F15B2211/00; F15B2211/50; F15B2211/505; F15B2211/50554; F15B2211/515; F15B2211/5158; F15B2211/52; F15B2211/526; F15B2211/528; F15B2211/565; F15B2211/575; F15B2211/60; F15B2211/63; F15B2211/6303; F15B2211/6336; F15B2211/665; F15B2211/6653; F15B2211/70; F15B2211/715; Y; Y10; Y10T; Y10T137/00; Y10T137/2496; Y10T137/2544
Claims Analysis
Total Claims: 10
Claim 1
Independent Claim
257 words
For use in antiskid control systems, a fluid pressure control valve for maintaining the fluid pressure supplied to an associated fluid pressure operated device at or as near a selected value as the operating conditions of the associated fluid pressure operated device indicate to be appropriate, said valve comprising a housing having an axially displaceable spindle, a spindle chamber for calibrated spring means acting against said spindle under the selected pressure, said spring means being arranged to act between the spindle and a movable abutment to provide a variable brake applying pressure, the spindle chamber being provided with inlet, outlet and exhaust ports, the axial position of the spindle within the chamber being arranged to alternatively allow communication between the inlet and outlet ports, thereby connecting the associated device to the selected pressure, or between the exhaust and outlet ports, thereby exhausting the pressure applied to the associated device, or to cut-off communication between any of these ports, the arrangement of the spindle being such that at any given moment the level of fluid pressure supplied to the associated device by the valve is proportional to the spring force exerted on the spindle by the spring means at that moment, said spring force being normally proportional to said selected pressure which is to insure that the selected pressure is supplied to the associated device, and also being variable in spring rate responsively to movement of the movable abutment effected by a change in the operating conditions of the associated device under the control of said valve means.
Claim 2
Dependent Claim
257 words
For use in antiskid control systems, a fluid pressure control valve for maintaining the fluid pressure supplied to an associated fluid pressure operated device at or as near a selected value as the operating conditions of the associated fluid pressure operated device indicate to be appropriate, said valve comprising a housing having an axially displaceable spindle, a spindle chamber for calibrated spring means acting against said spindle under the selected pressure, said spring means being arranged to act between the spindle and a movable abutment to provide a variable brake applying pressure, the spindle chamber being provided with inlet, outlet and exhaust ports, the axial position of the spindle within the chamber being arranged to alternatively allow communication between the inlet and outlet ports, thereby connecting the associated device to the selected pressure, or between the exhaust and outlet ports, thereby exhausting the pressure applied to the associated device, or to cut-off communication between any of these ports, the arrangement of the spindle being such that at any given moment the level of fluid pressure supplied to the associated device by the valve is proportional to the spring force exerted on the spindle by the spring means at that moment, said spring force being normally proportional to said selected pressure which is to insure that the selected pressure is supplied to the associated device, and also being variable in spring rate responsively to movement of the movable abutment effected by a change in the operating conditions of the associated device under the control of said valve means.
Claim 3
Dependent Claim
137 words
A valve according to claim 1 wherein the end of the spindle acted upon by the spring means is provided with a displaceable enclosure member in sealed sliding contact with the outside surface of the spindle, the enclosure member defining in conjunction with the associated end of the spindle a variable volume chamber, the spring means being arranged to act on the enclosure member, and hence the spindle, so as to tend to reduce the volume of the variable volume chamber the other end of the spindle being acted upon by the selected pressure, this pressure also being supplied to the variable volume chamber so that displacement of the enclosure member by the selected pressure against the spring means causes a corresponding reaction spring force from the spring means upon the enclosure member and hence the spiNdle.
Claim 4
Dependent Claim
14 words
A valve according to claim 1 wherein the spring means comprises a compression spring.
Claim 5
Dependent Claim
108 words
A valve according to claim 1 wherein the movable abutment comprises a displaceable control piston in sealed axial sliding contact within a fluid pressure containing control chamber, the control piston being spring-biased towards a datum position in the control chamber and the valve means being arranged to control the axial position of the control piston within the control chamber by adjusting the relative values of the pressures acting on either side of the control piston in the control chamber in order to deflect the control piston to the position giving the spring force appropriate to the operating conditions of the associated fluid pressure operated device at any moment.
Claim 6
Dependent Claim
27 words
A valve according to claim 7 wherein the control piston is biased towards the end of the control chamber adjacent the spring means by a compression spring.
Claim 7
Dependent Claim
40 words
A valve according to claim 4 wherein the side of the control piston arranged to be subjected alternatively to the selected pressure and to exhaust is provided with a greater effective area than the other side of the control piston.
Claim 8
Dependent Claim
20 words
A valve according to claim 4 wherein the valve means comprises a solenoid operated pilot valve incorporated within the housing.
Claim 9
Dependent Claim
47 words
A valve according to claim 4 wherein one side of the control piston is subjected to the selected pressure and the other side of the control piston is arranged to be alternatively connected, under the control of the valve means, to the selected pressure or to exhaust.
Claim 10
Dependent Claim
92 words
A valve according to claim 8 wherein the fluid pressure supply line to the side of the control piston which is arranged to be alternatively connected to the selected pressure or to exhaust is provided with two restrictor and non-return valve arrangements in parallel, one restrictor and non-return valve arrangement being arranged to control the rate of flow of fluid to this side of the control piston and the other restrictor and non-return valve arrangement being arranged to control the rate of exhausting of fluid from this side of the control piston.
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) | 1977-02-18 | 1977-08-20 | 1978-02-19 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1981-02-18 | 1981-08-20 | 1982-02-19 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1985-02-18 | 1985-08-20 | 1986-02-19 | $7700.00 | Window Closed / Lapsed |