US4750381A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Hydromechanical transmission
Assignee: Shimadzu Corp
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Filing: 1986-10-21
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Granted: 1988-06-14
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Expires: 2006-10-21
Abstract
Abstract A hydromechanical transmission that can be used as an efficient, continuously variable transmission has a differential mechanism, a hydraulic transmission mechanism, a mode selector mechanism, a locking mechanism, and a clutch mechanism. The hydraulic transmission mechanism has two pump/motors one of which acts as a hydraulic pump when the other serves as a hydraulic motor, and vice-versa. The mode selector establishes either a low-speed more or a high-speed mode. When one of the two pump/motors operates at a low speed in a given range of higher speeds in the high-speed mode, the input/output shaft of the pump/motor is locked by the locking mechanism. When the locking mechanism is in operation, the other pump/motor operating at a higher speed is disconnected from the differential mechanism by the clutch mechanism.
Inventors
- 👤 Yasuo Kita
- 👤 Yoshihiko Nakakoji
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-30 20:15
CPC Classifications
F; F16; F16H; F16H47/00; F16H47/02; F16H47/04; F16H37/00; F16H37/02; F16H37/06; F16H37/08; F16H37/0833; F16H37/084; F16H2037/0866; F16H2037/0873; Y; Y10; Y10T; Y10T74/00; Y10T74/19; Y10T74/19023; Y10T74/19037
Claims Analysis
Total Claims: 6
Claim 1
Independent Claim
203 words
A hydromechanical transmission having an input shaft and an output shaft, comprising: a differential mechanism having first, second, and third input/output ends and forming either a first mechanical transfer line for low speeds between the first and second input/output ends or a second mechanical transfer line for high speeds between the first and third input/output ends; a hydraulic power transmission mechanism having two pump/motors one of which acts as a hydraulic pump when the other serves as a hydraulic motor and vice-versa, an input/output shaft of one of the pump/motors being connected to the second input/output end of the differential mechanism, an input/output shaft of the other being connected to the third input/output end, the two pump/motors cooperating to constitute continuously variable speed hydraulic power transmission lines; a mode selector mechanism for establishing either a low-speed mode, in which the output of the hydromechanical transmission is connected to the input via the first mechanical transfer line, or a high-speed mode, in which the output is connected to the input via the second mechanical transfer line; and a locking mechanism for locking the input/output shaft of the pump/motor, operating at a low speed in a certain range of high speeds, in the high-speed mode.
Claim 2
Dependent Claim
203 words
A hydromechanical transmission having an input shaft and an output shaft, comprising: a differential mechanism having first, second, and third input/output ends and forming either a first mechanical transfer line for low speeds between the first and second input/output ends or a second mechanical transfer line for high speeds between the first and third input/output ends; a hydraulic power transmission mechanism having two pump/motors one of which acts as a hydraulic pump when the other serves as a hydraulic motor and vice-versa, an input/output shaft of one of the pump/motors being connected to the second input/output end of the differential mechanism, an input/output shaft of the other being connected to the third input/output end, the two pump/motors cooperating to constitute continuously variable speed hydraulic power transmission lines; a mode selector mechanism for establishing either a low-speed mode, in which the output of the hydromechanical transmission is connected to the input via the first mechanical transfer line, or a high-speed mode, in which the output is connected to the input via the second mechanical transfer line; and a locking mechanism for locking the input/output shaft of the pump/motor, operating at a low speed in a certain range of high speeds, in the high-speed mode.
Claim 3
Dependent Claim
231 words
A hydromechanical transmission having an input shaft and an output shaft comprising: a differential mechanism having first, second, and third input/output ends and forming either a first mechanical transfer line for low speeds between the first and second input/output ends or a second mechanical transfer line for high speeds between the first and third input/output ends; a hydraulic power transmission mechanism having two pump/motors one of which acts as a hydraulic pump when the other serves as a hydraulic motor and vice versa, an input/output shaft of one of the pump/motors being connected to the second input/output end of the differential mechanism, an input/output shaft of the other being connected to the third input/output end, the two pump/motors cooperating to constitute continuously variable speed hydraulic power transmission lines; a mode selector mechanism for establishing either a low-speed mode, in which the output of the hydromechanical transmission is connected to the input via the first mechanical transfer line, or a high-speed mode, in which the output is connected to the input via the second mechanical transfer line; a locking mechanism for locking the input/output shaft of the pump/motor, acting as a pump in a certain range of high speeds, in the high-speed mode; and a clutch mechanism acting to disconnect the input/output shaft of the pump/motor operating at a higher speed from the differential mechanism when said locking mechanism is in operation.
Claim 4
Dependent Claim
231 words
A hydromechanical transmission having an input shaft and an output shaft comprising: a differential mechanism having first, second, and third input/output ends and forming either a first mechanical transfer line for low speeds between the first and second input/output ends or a second mechanical transfer line for high speeds between the first and third input/output ends; a hydraulic power transmission mechanism having two pump/motors one of which acts as a hydraulic pump when the other serves as a hydraulic motor and vice versa, an input/output shaft of one of the pump/motors being connected to the second input/output end of the differential mechanism, an input/output shaft of the other being connected to the third input/output end, the two pump/motors cooperating to constitute continuously variable speed hydraulic power transmission lines; a mode selector mechanism for establishing either a low-speed mode, in which the output of the hydromechanical transmission is connected to the input via the first mechanical transfer line, or a high-speed mode, in which the output is connected to the input via the second mechanical transfer line; a locking mechanism for locking the input/output shaft of the pump/motor, acting as a pump in a certain range of high speeds, in the high-speed mode; and a clutch mechanism acting to disconnect the input/output shaft of the pump/motor operating at a higher speed from the differential mechanism when said locking mechanism is in operation.
Claim 5
Dependent Claim
39 words
A hydromechanical transmission as set forth in either of claims 1 or 2, wherein said locking mechanism brings the input/output shaft of said pump/motor connected to the second input/output end into and out of engagement with a stationary member.
Claim 6
Dependent Claim
37 words
A hydromechanical transmission as set forth in claim 2, wherein the clutch mechanism is mounted between the third input/output end of the differential mechanism and the input/output shaft of the pump/motor connected to the third input/output end.
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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) | 1991-06-14 | 1991-12-14 | 1992-06-14 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1995-06-14 | 1995-12-14 | 1996-06-14 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1999-06-14 | 1999-12-14 | 2000-06-14 | $7700.00 | Window Closed / Lapsed |