Patent US3788774A successfully refreshed from Google Patents.
US3788774A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Power output regulated pump arrangement
Assignee: Bosch Rexroth AG
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Filing: 1973-01-10
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Granted: 1974-01-29
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Expires: 1993-01-10
Abstract
Abstract An adjustable main pump whose output volume is controlled by a servomotor operated by an auxilliary pump controlled by control valves, is provided with pressure regulating cylinder and piston means receiving fluid from the auxilliary pump and supplying fluid to the servomotor through the control valves. A pressure responsive piston is controlled by high pressure fluid from the outlet of the adjustable main pump, and acts on the regulating piston, forming a variable throttle therewith for controlling the flow from the regulating cylinder to a low pressure discharge conduit, or to the servomotor, depending on the pressure exerted by the pressure responsive piston on the regulating piston, so that the product of pump pressure and pumped volume, representing the power output of the main pump, remains constant during regulating movement of the pressure responsive piston.
Inventors
- 👤 H Roesslein
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-06 14:18
CPC Classifications
F; F04; F04B; F04B49/00; F04B49/002; F04B2201/00; F04B2201/12; F04B2201/1203; Y; Y10; Y10T; Y10T137/00; Y10T137/8593; Y10T137/86493; Y10T137/86574; Y10T137/86582; Y10T137/8659
Claims Analysis
Total Claims: 13
Claim 1
Independent Claim
242 words
Power output regulated pump arrangement, comprising pump means having at least one high pressure conduit, and output volume adjusting means; servo motor means including a source of fluid under pressure, a hydraulic servo motor for operating said adjusting means, and control valve means connecting said source with said servo motor; and regulating means including a regulating cylinder, and a regulating piston forming in said regulating cylinder a first chamber connected with said source and a second chamber, a throttle duct means connecting said source with said second chamber and being connected with said control valve means for controlling said source to operate said servo motor, said regulating piston having a first portion projecting out of said regulating cylinder and being formed with a channel connecting said second chamber with a port in said first portion, first spring means biassing said regulating piston to move into said first chamber, pressure responsive piston means having a second portion and being urged by high pressure in said high pressure conduit toward said first portion so that said first and second portions abut each other and form with said port a variable throttle, and second spring means biassing said pressure responsive piston means away from said first portion, said second portion forming a passage connecting said second chamber with a low pressure discharge conduit through said variable throttle, said passage being closed when high pressure acting on said pressure responsive piston means closes said variable throttle.
Claim 2
Dependent Claim
242 words
Power output regulated pump arrangement, comprising pump means having at least one high pressure conduit, and output volume adjusting means; servo motor means including a source of fluid under pressure, a hydraulic servo motor for operating said adjusting means, and control valve means connecting said source with said servo motor; and regulating means including a regulating cylinder, and a regulating piston forming in said regulating cylinder a first chamber connected with said source and a second chamber, a throttle duct means connecting said source with said second chamber and being connected with said control valve means for controlling said source to operate said servo motor, said regulating piston having a first portion projecting out of said regulating cylinder and being formed with a channel connecting said second chamber with a port in said first portion, first spring means biassing said regulating piston to move into said first chamber, pressure responsive piston means having a second portion and being urged by high pressure in said high pressure conduit toward said first portion so that said first and second portions abut each other and form with said port a variable throttle, and second spring means biassing said pressure responsive piston means away from said first portion, said second portion forming a passage connecting said second chamber with a low pressure discharge conduit through said variable throttle, said passage being closed when high pressure acting on said pressure responsive piston means closes said variable throttle.
Claim 3
Dependent Claim
44 words
Regulated pump arrangement as claimed in claim 1 wherein said throttle duct means penetrates said regulating piston for connecting said first and second chambers so that fluid from said source flows through said first chamber and said throttle duct means into said second chamber.
Claim 4
Dependent Claim
56 words
Regulated pump arrangement as claimed in claim 1 wherein said pressure responsive piston forms first and second cylinder chambers, said first cylinder chamber being connected with said high pressure conduit, said second portion projecting from said said second cylinder chamber, and wherein said pressure responsive piston has a throttle connecting said first and second cylinder chambers.
Claim 5
Dependent Claim
17 words
Regulated pump arrangement as claimed in claim 3 wherein said pressure responsive piston is a differential piston.
Claim 6
Dependent Claim
39 words
Regulated pump arrangement as claimed in claim 3 wherein said second portion has a flat end face, and wherein said first portion has said port cooperating with the center of said flat end face to form said variable throttle.
Claim 7
Dependent Claim
25 words
Regulated pump arrangement as claimed in claim 5 wherein said pasSage in said first portion ending in said port is perpendicular to said flat face.
Claim 8
Dependent Claim
61 words
Regulated pump arrangement as claimed in claim 1 wherein said secon portion includes a first part integral with said pressure responsive piston, and a second part aligned with said first part and biassed by said second spring means against said first part and said pressure responsive piston, said second part having an end face forming with said port said variable throttle.
Claim 9
Dependent Claim
69 words
Regulated pump arrangement as claimed in claim 1 wherein said regulating piston means has a piston rod projecting through said first chamber out of said regulating cylinder; and comprising an abutment means engaged by said piston rod in an end position after movement of said regulating piston by said pressure responsive piston due to high pressure in said high pressure conduit against the action of said second spring means.
Claim 10
Dependent Claim
16 words
Regulating pump arrangement as claimed in claim 8 wherein said abutment means includes a threaded member.
Claim 11
Dependent Claim
58 words
Regulated pump arrangement as claimed in claim 1 comprising a stationary cylinder in which said pressure responsive piston means forms first and second cylinder chambers, said first cylinder chamber being connected with said high pressure conduit; and comprising a valve having an open position connecting said second cylinder with a low pressure discharge area, and a closed position.
Claim 12
Dependent Claim
56 words
Regulated pump arrangement as claimed in claim 10 comprising actuating means for said valve including a pressure conduit connected with said first cylinder chamber and means operated by the pressure in said pressure conduit to open said valve , and adjustable spring means for closing said valve at low pressure in said high pressure conduit means.
Claim 13
Dependent Claim
100 words
Regulated pump arrangement as claimed in claim 1 wherein said throttle duct means penetrates said regulating piston for connecting said first and second chambers so that fluid from said source flows through said first chamber and said throttle duct means into said second chamber, wherein said pressure responsive piston froms first and second cylinder chambers, said first cylinder chamber being connected with said high pressure conduit, said second portion projecting from said second cylinder chamber, wherein said pressure responsive piston has a throttle connecting said first and second cylinder chambers, and wherein said pressure responsive piston is a differential piston.
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USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1977-01-28 | 1977-07-30 | 1978-01-29 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1981-01-28 | 1981-07-30 | 1982-01-29 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1985-01-28 | 1985-07-30 | 1986-01-29 | $7700.00 | Window Closed / Lapsed |