US3717212A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Steer control for hydrostatic system
Assignee: Motors Liquidation Co
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Filing: 1971-09-20
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Granted: 1973-02-20
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Expires: 1991-09-20
Abstract
Abstract A servo control system for use with a steer by driving vehicle in which the steer propulsion is generated by a hydrostatic drive which provides steer bias to the propulsion. A pair of operator controlled servo mechanisms control the displacement of the pump for the hydrostatic drive. One of the servos is effective during forward driving and the other is effective during reverse driving thus permitting the operator to move the steer control lever in one direction for right turn and another direction for left turn. A spool valve controls the distribution of the control fluid to the pump displacement control motors from the servo mechanisms.
Inventors
- 👤 C Potter
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-09 00:06
CPC Classifications
B; B62; B62D; B62D11/00; B62D11/02; B62D11/06; B62D11/10; B62D11/14; B62D11/18; B62D11/183
Claims Analysis
Total Claims: 8
Claim 1
Independent Claim
236 words
A steer control for a steer by driving transmission including a variable displacement steer control pump having first and second displacement control means, said steer control comprising fluid sourcE means; manual control means movable to right and left turn positions; forward turn servo control means operatively connected with said manual control means and being in fluid communication with said source means; reverse turn servo control means operatively connected with said manual control means and being in fluid communication with said source means; and forwardreverse valve means selectively movable to a forward position and a reverse position for selectively providing fluid communication between said forward turn servo control means and the first and second displacement control means and between said reverse turn servo control means and the first and second displacement control means, whereby when said forward-reverse valve means is in the forward position and said manual control means is moved to the right turn position the first displacement control means will be pressurized, and when said manual control means is moved to the left turn position the second displacement control means will be pressurized; and when said forward-reverse valve means is in the reverse position and said manual control means is moved to said right turn position the second displacement control means will be pressurized, and when said manual control means is moved to said left turn position the first displacement control means will be pressurized.
Claim 2
Dependent Claim
236 words
A steer control for a steer by driving transmission including a variable displacement steer control pump having first and second displacement control means, said steer control comprising fluid sourcE means; manual control means movable to right and left turn positions; forward turn servo control means operatively connected with said manual control means and being in fluid communication with said source means; reverse turn servo control means operatively connected with said manual control means and being in fluid communication with said source means; and forwardreverse valve means selectively movable to a forward position and a reverse position for selectively providing fluid communication between said forward turn servo control means and the first and second displacement control means and between said reverse turn servo control means and the first and second displacement control means, whereby when said forward-reverse valve means is in the forward position and said manual control means is moved to the right turn position the first displacement control means will be pressurized, and when said manual control means is moved to the left turn position the second displacement control means will be pressurized; and when said forward-reverse valve means is in the reverse position and said manual control means is moved to said right turn position the second displacement control means will be pressurized, and when said manual control means is moved to said left turn position the first displacement control means will be pressurized.
Claim 3
Dependent Claim
236 words
A steer control for a steer by driving transmission including a variable displacement steer control pump having first and second displacement control means, said steer control comprising fluid sourcE means; manual control means movable to right and left turn positions; forward turn servo control means operatively connected with said manual control means and being in fluid communication with said source means; reverse turn servo control means operatively connected with said manual control means and being in fluid communication with said source means; and forward-reverse valve means selectively movable to a forward position and a reverse position for selectively providing fluid communication between said forward turn servo control means and the first and second displacement control means and between said reverse turn servo control means and the first and second displacement control means, whereby when said forward-reverse valve means is in the forward position and said manual control means is moved to the right turn position the first displacement control means will be pressurized, and when said manual control means is moved to the left turn position the second displacement control means will be pressurized; and when said forward-reverse valve means is in the reverse position and said manual control means is moved to said right turn position the second displacement control means will be pressurized, and when said manual control means is moved to said left turn position the first displacement control means will be pressurized.
Claim 4
Dependent Claim
236 words
A steer control for a steer by driving transmission including a variable displacement steer control pump having first and second displacement control means, said steer control comprising fluid sourcE means; manual control means movable to right and left turn positions; forward turn servo control means operatively connected with said manual control means and being in fluid communication with said source means; reverse turn servo control means operatively connected with said manual control means and being in fluid communication with said source means; and forward-reverse valve means selectively movable to a forward position and a reverse position for selectively providing fluid communication between said forward turn servo control means and the first and second displacement control means and between said reverse turn servo control means and the first and second displacement control means, whereby when said forward-reverse valve means is in the forward position and said manual control means is moved to the right turn position the first displacement control means will be pressurized, and when said manual control means is moved to the left turn position the second displacement control means will be pressurized; and when said forward-reverse valve means is in the reverse position and said manual control means is moved to said right turn position the second displacement control means will be pressurized, and when said manual control means is moved to said left turn position the first displacement control means will be pressurized.
Claim 5
Dependent Claim
131 words
A steer control for a steer by driving transmission including a variable displacement pump having displacement control means, said steer control comprising fluid source means; manual control means movable to first and second control positions; forward servo control means operatively connected with said manual control means and the displacement control means and being in fluid communication with said fluid source means; reverse servo control means operatively connected with said manual control means and said displacement control means and being in fluid communication with said fluid source means; and control valve means movable to a first position for controlling fluid communication between said forward servo control means and the displacement control means and to a second position for controlling fluid communication between said reverse servo control means and the displacement control means.
Claim 6
Dependent Claim
131 words
A steer control for a steer by driving transmission including a variable displacement pump having displacement control means, said steer control comprising fluid source means; manual control means movable to first and second control positions; forward servo control means operatively connected with said manual control means and the displacement control means and being in fluid communication with said fluid source means; reverse servo control means operatively connected with said manual control means and said displacement control means and being in fluid communication with said fluid source means; and control valve means movable to a first position for controlling fluid communication between said forward servo control means and the displacement control means and to a second position for controlling fluid communication between said reverse servo control means and the displacement control means.
Claim 7
Dependent Claim
226 words
A steer control for a drive by steering transmission including a variable displacement steer control pump having first and second displacement control means, said steer control comprising fluid source means; manual control means movable to right and left turn positions; forward turn servo control means operatively connected with said manual control means; reverse turn servo control means operatively connected with said manual control means; and forward-reverse valve means selectively movable to a forward position and a reverse position for selectively providing fluid communication between said fluid source means, said forward turn servo control means and the first and second displacement control means and between said fluid source means, said reverse turn servo control means and the first and second displacement control means, whereby when said forward-reverse valve means is in the forward position and said manual control means is moved to the right turn position the first displacement control means will be pressurized, and when said manual control means is moved to the left turn position the second displacement control means will be pressurized; and when said forward-reverse valve means is in the reverse position and said manual control means is moved to said right turn position the second displacement control means will be pressurized, and when said manual control means is moved to said left turn position the first displacement control means will be pressurized.
Claim 8
Dependent Claim
226 words
A steer control for a drive by steering transmission including a variable displacement steer control pump having first and second displacement control means, said steer control comprising fluid source means; manual control means movable to right and left turn positions; forward turn servo control means operatively connected with said manual control means; reverse turn servo control means operatively connected with said manual control means; and forward-reverse valve means selectively movable to a forward position and a reverse position for selectively providing fluid communication between said fluid source means, said forward turn servo control means and the first and second displacement control means and between said fluid source means, said reverse turn servo control means and the first and second displacement control means, whereby when said forward-reverse valve means is in the forward position and said manual control means is moved to the right turn position the first displacement control means will be pressurized, and when said manual control means is moved to the left turn position the second displacement control means will be pressurized; and when said forward-reverse valve means is in the reverse position and said manual control means is moved to said right turn position the second displacement control means will be pressurized, and when said manual control means is moved to said left turn position the first displacement control means will be pressurized.
References Cited (Backward Citations)
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1976-02-20 | 1976-08-21 | 1977-02-20 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1980-02-20 | 1980-08-21 | 1981-02-20 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1984-02-20 | 1984-08-21 | 1985-02-20 | $7700.00 | Window Closed / Lapsed |