Patent US3756030A successfully refreshed from Google Patents.
US3756030A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Hydrostatic transmission control with hydraulic follow-up
Assignee: International Motors LLC
•
Filing: 1972-03-02
•
Granted: 1973-09-04
•
Expires: 1992-03-02
Abstract
Abstract A hydraulic follow-up for use with a hydraulic system placed between a rotating input member and a rotating output member. The hydraulic system is a hydrostatic transmission for driving a tractor, and comprises a hydrostatic pump and a hydrostatic motor driven by the pump. When the hydrostatic pump is angularly shifted with respect to the input member, the shifting is controlled by the hydraulic follow-up, which also shifts the motor in relation to the output member.
Inventors
- 👤 P Chatterjea
- 👤 C Ruhl
- 👤 E Meyer
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-04 08:46
CPC Classifications
F; F16; F16H; F16H61/00; F16H61/38; F16H61/40; F16H61/42; F16H61/433; B; B62; B62D; B62D11/00; B62D11/02; B62D11/06; B62D11/10; B62D11/14; B62D11/18; B62D11/183
Claims Analysis
Total Claims: 4
Claim 1
Independent Claim
350 words
In an assembly in which an adjuster acting between a pump and a driving part therefor is associated with a pair of pressure chambers so as to provide for a pressure imbalance of a given sign between the pressure chambers to increase the driving ratio of driving part to pump, a pressure imbalance of the opposite sign to decrease said driving ratio, and a pressure balance to fix said driving ratio; and anotHer adjuster acting between a motor driven by the pump and a driven part driven by the motor is associated with another pair of pressure chambers so as to provide for a pressure imbalance of one sign between the lastnamed chambers to increase the driving ratio of motor to driven part, a pressure imbalance of the opposite sign to decrease the last-named driving ratio, and a pressure balance to fix the last named ratio; the combination with the said adjusters, of a. means forming first, second, and third restricted orifices of appreciable length; b. means connecting one end and the other end of each of the first and second orifices to an intermediate fluid pressure and to drain pressure, respectively, for flowing pressure fluid through the first and second orifices; c. means connecting one end and the other end of the third orifice to high fluid pressure and to intermediate fluid pressure for flowing pressure fluid through the third orifice; d. means for adjustably connecting one pressure chamber associated with the adjuster for the pump and one pressure chamber associated with the adjuster for the motor with various points along the first orifice; e. means for adjustably connecting the other pressure chamber associated with the pump adjuster with various points along the second orifice; f. means for causing adjustment of the driving ratio between driving part and pump to act against the last-named means; g. means for adjustably connecting the other pressure chamber associated with the motor adjuster to various points along the third orifice; and h. means for causing adjustment of the driving ratio between the motor and the driven part to act against the last-named means.
Claim 2
Dependent Claim
350 words
In an assembly in which an adjuster acting between a pump and a driving part therefor is associated with a pair of pressure chambers so as to provide for a pressure imbalance of a given sign between the pressure chambers to increase the driving ratio of driving part to pump, a pressure imbalance of the opposite sign to decrease said driving ratio, and a pressure balance to fix said driving ratio; and anotHer adjuster acting between a motor driven by the pump and a driven part driven by the motor is associated with another pair of pressure chambers so as to provide for a pressure imbalance of one sign between the lastnamed chambers to increase the driving ratio of motor to driven part, a pressure imbalance of the opposite sign to decrease the last-named driving ratio, and a pressure balance to fix the last named ratio; the combination with the said adjusters, of a. means forming first, second, and third restricted orifices of appreciable length; b. means connecting one end and the other end of each of the first and second orifices to an intermediate fluid pressure and to drain pressure, respectively, for flowing pressure fluid through the first and second orifices; c. means connecting one end and the other end of the third orifice to high fluid pressure and to intermediate fluid pressure for flowing pressure fluid through the third orifice; d. means for adjustably connecting one pressure chamber associated with the adjuster for the pump and one pressure chamber associated with the adjuster for the motor with various points along the first orifice; e. means for adjustably connecting the other pressure chamber associated with the pump adjuster with various points along the second orifice; f. means for causing adjustment of the driving ratio between driving part and pump to act against the last-named means; g. means for adjustably connecting the other pressure chamber associated with the motor adjuster to various points along the third orifice; and h. means for causing adjustment of the driving ratio between the motor and the driven part to act against the last-named means.
Claim 3
Dependent Claim
331 words
In an assembly in which a rotating driving part drives a hydrostatic pump by virtue of an angle between the axes of the driving part and the pump; a piston-and-cylinder unit for the pump controls the angle between the axes of the pump and driving part and is controlled by a valve operated by opposed pressure chambers; a hydrostatic motor is hydraulically driven by the hydrostatic pump; a rotating driven part is driven by the hydrostatic motor by virtue of the angle between the axes of the motor and the driven part and operates faster with a decrease in the last-named angle; and a piston-and-cylinder unit for the motor controls the last-named angle and is controlled by a valve operated by opposed pressure chambers; the combination with the piston-and-cylinder units and the valves, of a. means forming first, second, and third restricted orifices of appreciable length; b. means connecting one end and the other end of each of the first and second orifices to an intermediate fluid pressure and to drain pressure, respectively, for flowing pressure fluid through the first and second orifices; c. means connecting one end and the other end of the third orifice to high fluid pressure and to intermediate fluid pressure for flowing pressure fluid through the third orifice; d. means for adjustably connecting one pressure chamber of the valve for the pump and one pressure chamber of the valve for the motor with various points along the first orifice; e. means for adjustably connecting the other pressure chamber of the pump valve with various points along the second orifice; f. means for causing relative adjustment of the psiton and cylinder of the unit for the pump to act against the last-named means; g. means for adjustably connecting the other pressure chamber of the motor valve with various points along the third orifice; and h. means for causing relative adjustment of the piston and cylinder of the unit for the motor to act against the last-named means.
Claim 4
Dependent Claim
331 words
In an assembly in which a rotating driving part drives a hydrostatic pump by virtue of an angle between the axes of the driving part and the pump; a piston-and-cylinder unit for the pump controls the angle between the axes of the pump and driving part and is controlled by a valve operated by opposed pressure chambers; a hydrostatic motor is hydraulically driven by the hydrostatic pump; a rotating driven part is driven by the hydrostatic motor by virtue of the angle between the axes of the motor and the driven part and operates faster with a decrease in the last-named angle; and a piston-and-cylinder unit for the motor controls the last-named angle and is controlled by a valve operated by opposed pressure chambers; the combination with the piston-and-cylinder units and the valves, of a. means forming first, second, and third restricted orifices of appreciable length; b. means connecting one end and the other end of each of the first and second orifices to an intermediate fluid pressure and to drain pressure, respectively, for flowing pressure fluid through the first and second orifices; c. means connecting one end and the other end of the third orifice to high fluid pressure and to intermediate fluid pressure for flowing pressure fluid through the third orifice; d. means for adjustably connecting one pressure chamber of the valve for the pump and one pressure chamber of the valve for the motor with various points along the first orifice; e. means for adjustably connecting the other pressure chamber of the pump valve with various points along the second orifice; f. means for causing relative adjustment of the psiton and cylinder of the unit for the pump to act against the last-named means; g. means for adjustably connecting the other pressure chamber of the motor valve with various points along the third orifice; and h. means for causing relative adjustment of the piston and cylinder of the unit for the motor to act against the last-named means.
References Cited (Backward Citations)
US2161439A
Cited
US3247669A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1976-09-03 | 1977-03-05 | 1977-09-04 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1980-09-03 | 1981-03-05 | 1981-09-04 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1984-09-03 | 1985-03-05 | 1985-09-04 | $7700.00 | Window Closed / Lapsed |