Patent US4574904A successfully refreshed from Google Patents.
US4574904A
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US
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Auxilliary steering system
Assignee: Link Belt Cranes LP LLLP
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Filing: 1984-02-03
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Granted: 1986-03-11
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Expires: 2004-02-03
Abstract
Abstract An auxilliary hydraulic steering system for use on mobile vehicles having an engine-driven pump supplying hydraulic fluid under pressure to a steering control unit and an accumulator. The accumulator is charged with fluid under pressure from the pump through a charge/discharge valve and connects with the supply line to the steering control unit only when this valve shifts in response to a predetermined pressure in said supply line.
Inventors
- 👤 Frederick R. Goode
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-29 22:45
CPC Classifications
B; B62; B62D; B62D5/00; B62D5/06; B62D5/30; B62D5/32
Claims Analysis
Total Claims: 4
Claim 1
Independent Claim
149 words
An auxiliary steering system for a mobile vehicle having at least one axle with steerable ground-engaging wheels; comprising: a first engine-driven pump for supplying hydraulic fluid under pressure; a first steering cylinder connected to said wheels to determine angular orientation thereof; an operator-manipulated steering control unit interposed between said first pump and steering cylinder to control the flow of hydraulic fluid from said first pump to the steering cylinder; an accumulator for storing energy needed for auxiliary steering; a second engine-driven pump connected to supply hydraulic fluid to said accumulator; a charge/discharge valve interposed between said second pump and said accumulator; a charge conduit connected to said charge/discharge valve and the output of said first pump; a first check valve in the output of said first pump upstream of the connection with said charge conduit; and a second check valve interposed between said second pump and said charge/discharge valve.
Claim 2
Dependent Claim
149 words
An auxiliary steering system for a mobile vehicle having at least one axle with steerable ground-engaging wheels; comprising: a first engine-driven pump for supplying hydraulic fluid under pressure; a first steering cylinder connected to said wheels to determine angular orientation thereof; an operator-manipulated steering control unit interposed between said first pump and steering cylinder to control the flow of hydraulic fluid from said first pump to the steering cylinder; an accumulator for storing energy needed for auxiliary steering; a second engine-driven pump connected to supply hydraulic fluid to said accumulator; a charge/discharge valve interposed between said second pump and said accumulator; a charge conduit connected to said charge/discharge valve and the output of said first pump; a first check valve in the output of said first pump upstream of the connection with said charge conduit; and a second check valve interposed between said second pump and said charge/discharge valve.
Claim 3
Dependent Claim
17 words
The invention according to claim 1, wherein said second pump is a pressure compensated, variable displacement pump.
Claim 4
Dependent Claim
15 words
The invention according to claim 2, wherein said first pump is a fixed displacement pump.
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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) | 1989-03-10 | 1989-09-09 | 1990-03-11 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1993-03-10 | 1993-09-09 | 1994-03-11 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1997-03-10 | 1997-09-09 | 1998-03-11 | $7700.00 | Window Closed / Lapsed |