US3811587A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Hydraulic leveling circuit for implement
Assignee: Case LLC
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Filing: 1972-07-17
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Granted: 1974-05-21
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Expires: 1992-07-17
Abstract
Abstract The disclosure relates to a hydraulic circuit for a vehicle having a boom pivoted thereon by a boom ram and a bucket pivoted on the boom by a bucket ram. The hydraulic circuit includes a main pump that supplies fluid under pressure from a reservoir to the boom and bucket rams through control vales. An auxiliary circuit supplies fluid from the reservoir to the bucket ram to maintain the material handling unit at a predetermined attitude with respect to the reference plane and the auxiliary circuit includes a pump that is driven by the flow of fluid between the boom control valve and the boom ram.
Inventors
- 👤 D Seaberg
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-28 10:17
CPC Classifications
E; E02; E02F; E02F3/00; E02F3/04; E02F3/28; E02F3/36; E02F3/42; E02F3/43; E02F3/431; E02F3/432; E02F3/433
Claims Analysis
Total Claims: 15
Claim 1
Independent Claim
170 words
In a vehicle having a boom pivoted thereon; a boom ram for raising and lowering said boom on said vehicle; a material handling unit pivoted on said boom; a unit ram for pivoting said unit on said boom; and a hydraulic circuit for supplying fluid to said rams, said hydraulic circuit including a reservoir; pump means for supplying fluid under pressure from said reservoir; first hydraulic circuit means connecting said pump means and said reservoir to said boom ram to raise and lower said boom; second hydraulic circuit means connecting said pump means and said reservoir to said unit ram; and auxiliary hydraulic circuit means cooperating with said first hydraulic circuit means and connected to said second hydraulic circuit means for supplying fluid from said reservoir to said unit ram and maintaining a predetermined attitude of said unit with respect to a reference plane as said boom is raised and lowered on said vehicle, said auxiliary hydraulic circuit means including an auxiliary pump cooperating with said first hydraulic circuit means.
Claim 2
Dependent Claim
170 words
In a vehicle having a boom pivoted thereon; a boom ram for raising and lowering said boom on said vehicle; a material handling unit pivoted on said boom; a unit ram for pivoting said unit on said boom; and a hydraulic circuit for supplying fluid to said rams, said hydraulic circuit including a reservoir; pump means for supplying fluid under pressure from said reservoir; first hydraulic circuit means connecting said pump means and said reservoir to said boom ram to raise and lower said boom; second hydraulic circuit means connecting said pump means and said reservoir to said unit ram; and auxiliary hydraulic circuit means cooperating with said first hydraulic circuit means and connected to said second hydraulic circuit means for supplying fluid from said reservoir to said unit ram and maintaining a predetermined attitude of said unit with respect to a reference plane as said boom is raised and lowered on said vehicle, said auxiliary hydraulic circuit means including an auxiliary pump cooperating with said first hydraulic circuit means.
Claim 3
Dependent Claim
54 words
A vehicle as defined in claim 1, in which said first hydraulic means includes conduit means between said boom ram, said pump means and said reservoir; and in which said auxiliary hydraulic circuit means includes means in said conduit means for driving said auxiliary pump in response to fluid flow in said conduit means.
Claim 4
Dependent Claim
27 words
A vehicle as defined in claim 2, in which said means in said conduit means is an auxiliary motor having a shaft connected to said aUxiliary pump.
Claim 5
Dependent Claim
42 words
A vehicle as defined in claim 2, in which said conduit means includes first and second conduits leading from said boom ram and said means in said conduit means includes a reversible auxiliary motor having a shaft connected to said auxiliary pump.
Claim 6
Dependent Claim
44 words
A vehicle as defined in claim 4, in which said auxiliary hydraulic circuit means includes conduits leading from said reservoir to opposite sides of said auxiliary pump with each conduit having check valve means providing unidirectional flow from said reservoir to said auxiliary pump.
Claim 7
Dependent Claim
57 words
A vehicle as defined in claim 5, in which said auxiliary hydraulic circuit means includes an auxiliary valve and first and second conduits leading from said opposite sides of said auxiliary pump to said auxiliary valve, said first and second conduits each having check valve means providing unidirectional flow from said auxiliary pump to said auxiliary valve.
Claim 8
Dependent Claim
72 words
A vehicle as defined in claim 1, in which said auxiliary pump is reversible and said auxiliary hydraulic circuit means includes an auxiliary valve having first and second conduits leading from said auxiliary valve to said unit ram; and conduit means between said auxiliary valve and opposite sides of said auxiliary pump, said conduit means having valve means providing unidirectional flow from opposite sides of said auxiliary pump to said auxiliary valve.
Claim 9
Dependent Claim
42 words
A vehicle as defined in claim 1, in which said second hydraulic circuit means includes a control valve having first and second conduits leading from control valve to said unit ram and conduit means connecting said auxiliary pump to said control valve.
Claim 10
Dependent Claim
78 words
A vehicle as defined in claim 1, in which said auxiliary pump is reversible, said first hydraulic circuit means includes first and second conduits leading from said boom ram, and said auxiliary hydraulic circuit means includes an auxiliary motor in one of said first and second conduits and connected to said auxiliary pump to drive said auxiliary pump in either direction in response to fluid flow in either direction in said one of said first and second conduits.
Claim 11
Dependent Claim
121 words
In combination with a vehicle having a boom supported thereon with a boom ram adapted to raise and lower said boom and a material handling unit pivoted on the boom by a unit ram, a hydraulic circuit including a reservoir; a main pump; boom valve means; unit valve means; conduit means connecting (1) said valve means to said main pump and reservoir, (2) said boom valve means to said boom ram and (3) said unit valve means to said unit ram; and an auxiliary pump cooperating with the conduit means between said boom valve means and said boom ram for supplying fluid for said unit ram only when said boom valve means is actuated to direct fluid to said boom ram.
Claim 12
Dependent Claim
121 words
In combination with a vehicle having a boom supported thereon with a boom ram adapted to raise and lower said boom and a material handling unit pivoted on the boom by a unit ram, a hydraulic circuit including a reservoir; a main pump; boom valve means; unit valve means; conduit means connecting (1) said valve means to said main pump and reservoir, (2) said boom valve means to said boom ram and (3) said unit valve means to said unit ram; and an auxiliary pump cooperating with the conduit means between said boom valve means and said boom ram for supplying fluid for said unit ram only when said boom valve means is actuated to direct fluid to said boom ram.
Claim 13
Dependent Claim
50 words
The combination as defined in claim 10, in which said auxiliary pump is reversible, further including first and second conduits connected to opposite sides of said auxiliary pump to said reservoir, said conduits having check valve means providing unidirectional flow from said reservoir to opposite sides of said auxiliary pump.
Claim 14
Dependent Claim
71 words
The combination as defined in claim 11, and including further conduits connecting said first and second conduits to said unit valve means so that one of said first and second conduits supplies fluid from said reservoir to said auxiliary pump and the other of said first and second conduits supplies fluid from said auxiliary pump to said unit valve means when said boom valve means is moved from a neutral position.
Claim 15
Dependent Claim
33 words
The combination as defined in claim 11, including auxiliary valve means; and further conduits connecting said first and second conduits to said auxiliary valve means and said auxiliary means to said unit ram.
References Cited (Backward Citations)
US3563137A
Cited
US3695474A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1977-05-20 | 1977-11-19 | 1978-05-21 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1981-05-20 | 1981-11-19 | 1982-05-21 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1985-05-20 | 1985-11-19 | 1986-05-21 | $7700.00 | Window Closed / Lapsed |