US3784326A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Pressure compensated pump
Assignee: Colt Industries Operating Corp
•
Filing: 1972-01-24
•
Granted: 1974-01-08
•
Expires: 1992-01-24
Abstract
Abstract A constant pressure fluid source is provided by operating a balanced variable displacement vane pump as a pressure compensated device. The pressure differential across the pump is sensed and employed to hydraulically and automatically control pump displacement by adjusting the position of the movable seal blocks with respect to the rotor to thereby regulate flow in the interest of maintaining the desired output pressure.
Inventors
- 👤 J Lagana
- 👤 J Cygnor
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-05 03:43
CPC Classifications
F; F04; F04C; F04C14/00; F04C14/18; F04C14/22; F04C14/223; F04B; F04B49/00; F04B49/08
Claims Analysis
Total Claims: 10
Claim 1
Independent Claim
280 words
Apparatus for providing a constant pressure source of fluid comprising: variable displacement pump means, said pump meAns including at least a pair of cam blocks and a rotor at least partly circumscribed by said cam blocks, said cam blocks being radially movable with respect to said rotor to vary the displacement of said pump means, said pump means having at least an inlet port connected to a source of fluid and a pair of outlet passages, said outlet passages discharging through said cam blocks, said pump means further including a housing which defines at least a pair of oppositely disposed cylinders; piston means disposed in respective of said pump means housing cylinders, said piston means having fluid flow passages therethrough; tubular piston rod means connecting said piston means to respective of said pump means cam blocks whereby the position of said cam blocks may be varied by said piston means, said piston rod means providing fluid communication between said pump means outlet passages and said piston means passages whereby the pump means discharge pressure is applied to first ends of each of said piston means to urge said cam blocks in the direction of pump means maximum displacement; means for sensing the pressure differential across said pump means; and means connected to said sensing means and responsive to the pressure differential across the pump means for reducing the pressure applied to said piston means first ends when said pump means pressure rise exceeds a predetermined amount whereby said cam blocks may move in the direction of minimum displacement under the influence of dynamic and pressure forces acting on the faces of said cam blocks which face the pump means rotor.
Claim 2
Dependent Claim
280 words
Apparatus for providing a constant pressure source of fluid comprising: variable displacement pump means, said pump meAns including at least a pair of cam blocks and a rotor at least partly circumscribed by said cam blocks, said cam blocks being radially movable with respect to said rotor to vary the displacement of said pump means, said pump means having at least an inlet port connected to a source of fluid and a pair of outlet passages, said outlet passages discharging through said cam blocks, said pump means further including a housing which defines at least a pair of oppositely disposed cylinders; piston means disposed in respective of said pump means housing cylinders, said piston means having fluid flow passages therethrough; tubular piston rod means connecting said piston means to respective of said pump means cam blocks whereby the position of said cam blocks may be varied by said piston means, said piston rod means providing fluid communication between said pump means outlet passages and said piston means passages whereby the pump means discharge pressure is applied to first ends of each of said piston means to urge said cam blocks in the direction of pump means maximum displacement; means for sensing the pressure differential across said pump means; and means connected to said sensing means and responsive to the pressure differential across the pump means for reducing the pressure applied to said piston means first ends when said pump means pressure rise exceeds a predetermined amount whereby said cam blocks may move in the direction of minimum displacement under the influence of dynamic and pressure forces acting on the faces of said cam blocks which face the pump means rotor.
Claim 3
Dependent Claim
28 words
The apparatus of claim 1 further comprising: resilient means acting on said piston means first ends to bias said cam blocks in the direction of maximum pump displacement.
Claim 4
Dependent Claim
79 words
The apparatus of claim 1 wherein said pressure reducing means comprises: valve body means, said valve body means defining a valve chamber; drain means communicating with said valve chamber; first conduit means providing communication between said valve chamber and said pump housing defined cylinders at the first end sides of said piston means; and a pressure responsive valve member movable in said valve chamber for selectively establishing and interrupting communication between said first conduit means and said drain means.
Claim 5
Dependent Claim
89 words
The apparatus of claim 3 wherein said sensing means comprises: second conduit means for sensing the pump means inlet pressure, said second conduit means opening at one end into said valve chamber at one side of said movable valve member; and third conduit means for sensing the pump means discharge pressure, said third conduit means opening at one end into said valve chamber at the opposite side of said movable member whereby said pump means inlet and discharge pressure at applied to opposite sides of said movable valve member.
Claim 6
Dependent Claim
36 words
The apparatus of claim 4 wherein said pressure reducing means further comprises: resilient means contacting said movable valve member and cooperating with said pump means inlet pressure to urge said movable member in a first direction.
Claim 7
Dependent Claim
28 words
The apparatus of claim 5 further comprising: resilient means acting on said piston means first ends to bias said cam blocks in the direction of maximum pump displacement.
Claim 8
Dependent Claim
63 words
The apparatus of claim 4 wherein said pressure reducing means further comprises: fourth conduit means providing communication between said valve chamber and said pump means housing defined cylinders at the second end sides of said piston means, said movable valve member establishing communication between said fourth conduit means and said drain means when said pump means discharge pressure decreases below the predetermined level.
Claim 9
Dependent Claim
70 words
The apparatus of claim 7 wherein said movable valve member includes spacially displaced lands, said lands dividing said valve chamber into a pair of oppositely disposed distal sensing chambers and a plurality of intermediate chambers, said second and third conduit means normally opening into respective of said distal chamber portions and the valve chamber ends of said first and fourth conduit means normally being closed by respective of said lands.
Claim 10
Dependent Claim
57 words
The apparatus of claim 6 wherein said means applying pump means discharge pressure to first ends of said piston means in each of said piston means, said passage means providing continuous communication between the region between the pump means rotor and cam blocks and said pump means housing cylinders at the first ends of said piston means.
References Cited (Backward Citations)
US3527552A
Cited
US3547562A
Cited
US3567347A
Cited
US3560118A
Cited
US3663130A
Cited
US3645652A
Cited
US3672796A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1977-01-07 | 1977-07-09 | 1978-01-08 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1981-01-07 | 1981-07-09 | 1982-01-08 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1985-01-07 | 1985-07-09 | 1986-01-08 | $7700.00 | Window Closed / Lapsed |