Patent US3916767A successfully refreshed from Google Patents.
US3916767A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Hydraulic control circuit for vehicles
Assignee: Case LLC
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Filing: 1973-06-14
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Granted: 1975-11-04
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Expires: 1993-06-14
Abstract
Abstract A hydraulic control circuit for a front end loader is disclosed in this application. A device is used to interconnect a main and an auxiliary circuit so that additional fluid may be supplied to one of the circuits to operate a hydraulic device at a higher speed. In one embodiment, the main and auxiliary circuits are in parallel and the device is used to supply additional fluid from the auxiliary circuit to the main circuit. In a second embodiment, the main and auxiliary circuits are in series and the device is used to supply additional fluid to either the main or auxiliary circuit.
Inventors
- 👤 Robert M Barton
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-27 21:46
CPC Classifications
F; F15; F15B; F15B11/00; F15B11/16; F15B11/17; E; E02; E02F; E02F9/00; E02F9/20; E02F9/22; E02F9/2221; E02F9/2239; E02F9/2278; E02F9/2292; F15B2211/00; F15B2211/20; F15B2211/205; F15B2211/20576; F15B2211/30; F15B2211/305; F15B2211/30505; F15B2211/40; F15B2211/405; F15B2211/40515; F15B2211/45; F15B2211/70; F15B2211/71; F15B2211/7142; F15B2211/78; F15B2211/781
Claims Analysis
Total Claims: 8
Claim 1
Independent Claim
225 words
In a vehicle having a main hydraulic circuit including first and second hydraulic motor means, main pump means including first and second pumps, first conduit means connecting said first pump to said first motor means for supplying fluid under pressure to said first motor means, second conduit means connecting said second pump to said second motor means for supplying fluid under pressure to said second motor means, first and second control valves respectively located in said first and second conduit means for controlling flow between said pumps and said motor means, auxiliary pump means connected to auxiliary valve means for supplying fluid to operate a material handling means, selector valve means connected to said auxiliary valve means, first and second conduits respectively connecting said selector valve means to said first and second conduit means between said main pump means and the respective motor means, each of said first and second conduits having a check valve therein preventing flow from said first and second conduit means to said selector valve means to said conduit means so that additional fluid is supplied from said auxiliary pump means directly to said motor means when said selector valve means is in an operative position and the pressure of fluid from said selector valve means is greater than the pressure of the fluid in said first and second conduit means.
Claim 2
Dependent Claim
225 words
In a vehicle having a main hydraulic circuit including first and second hydraulic motor means, main pump means including first and second pumps, first conduit means connecting said first pump to said first motor means for supplying fluid under pressure to said first motor means, second conduit means connecting said second pump to said second motor means for supplying fluid under pressure to said second motor means, first and second control valves respectively located in said first and second conduit means for controlling flow between said pumps and said motor means, auxiliary pump means connected to auxiliary valve means for supplying fluid to operate a material handling means, selector valve means connected to said auxiliary valve means, first and second conduits respectively connecting said selector valve means to said first and second conduit means between said main pump means and the respective motor means, each of said first and second conduits having a check valve therein preventing flow from said first and second conduit means to said selector valve means to said conduit means so that additional fluid is supplied from said auxiliary pump means directly to said motor means when said selector valve means is in an operative position and the pressure of fluid from said selector valve means is greater than the pressure of the fluid in said first and second conduit means.
Claim 3
Dependent Claim
162 words
In a vehicle having a hydraulic circuit including first and second hydraulic motor means, first and second main pumps, first and second conduit means respectively connecting said first and second main pumps to said first and second hydraulic motor means, separate control valve means in each of said conduit means, auxiliary pump means, selector valve means connected to said auxiliary pump means, first and second branch conduits connecting said selector valve means respectively to said first and second conduit means between said main pumps and said control valve means, each of said branch conduits having a pressure responsive valve therein limiting flow in one direction from said selector valve means to said conduit means, and auxiliary valve means connected to said control valve means for supplying fluid to operate a material handling means, said selector valve means having an operative position for supplying fluid under pressure from said auxiliary pump means through said pressure responsive valves directly to said control valve means.
Claim 4
Dependent Claim
162 words
In a vehicle having a hydraulic circuit including first and second hydraulic motor means, first and second main pumps, first and second conduit means respectively connecting said first and second main pumps to said first and second hydraulic motor means, separate control valve means in each of said conduit means, auxiliary pump means, selector valve means connected to said auxiliary pump means, first and second branch conduits connecting said selector valve means respectively to said first and second conduit means between said main pumps and said control valve means, each of said branch conduits having a pressure responsive valve therein limiting flow in one direction from said selector valve means to said conduit means, and auxiliary valve means connected to said control valve means for supplying fluid to operate a material handling means, said selector valve means having an operative position for supplying fluid under pressure from said auxiliary pump means through said pressure responsive valves directly to said control valve means.
Claim 5
Dependent Claim
209 words
A vehicle having a main hydraulic circuit including first and second hydraulic motor means, first and second pumps for supplying fluid under pressure to said first and second motor means, first and second conduit means respectively connecting said first and second pumps to said first and second motor means, each of said conduit means having a control valve therein for individually controlling the flow of fluid under pressure from the respective pumps to the respective motor means, auxiliary pump means, selector valve means connected to said auxiliary pump means, first and second branch conduits connecting said selector valve means to said first and second conduit means, said branch conduits being respectively connected to said conduit means between said pumps and said control valves, each of said first and second conduits having a pressure responsive check valve therein limiting flow from said selector valve means to said first and second conduit means so that additional pressurized fluid is supplied directly to said first and second hydraulic motor (conduit) means from said auxiliary pump means when said selector valve means is in an operative position and the pressure of the fluid in said selector valve means is greater than the pressure of the flUid in the first and second conduit means.
Claim 6
Dependent Claim
209 words
A vehicle having a main hydraulic circuit including first and second hydraulic motor means, first and second pumps for supplying fluid under pressure to said first and second motor means, first and second conduit means respectively connecting said first and second pumps to said first and second motor means, each of said conduit means having a control valve therein for individually controlling the flow of fluid under pressure from the respective pumps to the respective motor means, auxiliary pump means, selector valve means connected to said auxiliary pump means, first and second branch conduits connecting said selector valve means to said first and second conduit means, said branch conduits being respectively connected to said conduit means between said pumps and said control valves, each of said first and second conduits having a pressure responsive check valve therein limiting flow from said selector valve means to said first and second conduit means so that additional pressurized fluid is supplied directly to said first and second hydraulic motor (conduit) means from said auxiliary pump means when said selector valve means is in an operative position and the pressure of the fluid in said selector valve means is greater than the pressure of the flUid in the first and second conduit means.
Claim 7
Dependent Claim
37 words
A vehicle as defined in claim 3, further including auxiliary valve means between said auxiliary pump means and said selector valve means for selectively supplying fluid from said auxiliary valve means to fluid operated material handling means.
Claim 8
Dependent Claim
55 words
A vehicle as defined in claim 3, in which each of said control valves has a neutral position and first and second operative positions, further including first and second auxiliary valves respectively connected to said control valves for supplying fluid to fluid operated material handling means when the control valves are in a neutral position.
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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) | 1978-11-03 | 1979-05-05 | 1979-11-04 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1982-11-03 | 1983-05-05 | 1983-11-04 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1986-11-03 | 1987-05-05 | 1987-11-04 | $7700.00 | Window Closed / Lapsed |