US4813306A
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: 1989-03-21
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Expires: 2006-10-21
Abstract
Abstract A hydromechanical transmission that can be used as a simple and efficient continuously variable transmission includes a differential mechanism for forming either a first mehanical transfer line for high speeds or a second mechanical transfer line for low speeds, a hydraulic power transmission mechanism having a hydraulic pump/motor, and a mode selector mechanism for selecting either a low-speed mode or a high-speed mode. In the low-speed mode, the output is connected to the input via the second mechanical transfer line. In the high-speed mode, the output is connected to the input via the first mechanical transfer line. One of the hydraulic pump/motors has a fixed displacement , while the other hydraulic pump/motor has a variable displacement.
Inventors
- 👤 Yasuo Kita
- 👤 Ryosuke Sugawara
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-03 23:13
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; F16H61/00; F16H61/38; F16H61/40; F16H61/42; F16H61/421; Y; Y10; Y10T; Y10T74/00; Y10T74/19; Y10T74/19023; Y10T74/19037
Claims Analysis
Total Claims: 2
Claim 1
Independent Claim
374 words
A hydromechanical transmission, comprising: (a) 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; (b) a hydraulic power transmission mechanism having a pair of hydraulic pump/motors including a first fixed displacement pump/motor and a second variable displacement pump/motor, wherein an input/output end of said first pump/motor is directly connected to said second input/output end of said differential mechanism, and an input/output end of said second pump/motor is connected to said third input/output end of said differential mechanism through a first pair of meshing gears, wherein the input/output ends of the first and second pump/motors are disposed on the same side of said hydraulic power transmission mechanism, such that said pump/motors cooperate with one another to constitute variable-speed hydraulic power transmission lines; and (c) a mode selector mechanism for selecting 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 wherein said differential mechanism is a planetary gear train, and the input/output end of said first pump/motor is directly connected to an output shaft of a sun gear of said planetary gear train, and wherein the input/output end of said second pump/motor is connected through said first pair of meshing gears to a ring gear of said planetary gear train, and further wherein the sun gear of said first mechanical transfer line is connected to a low speed clutch, for connecting to the output of said hydromechanical transmission, through a second pair of meshing gears, and said second mechanical transfer line is connected to a high speed clutch, for connecting to the output of said hydromechanical transmission, by a third pair of meshing gears, such that said low and high speed clutches are connected adjacent one another and in-line on an output shaft of the output of said hydromechanical transmission, and also such that said second and third pairs of meshing gears are also positioned adjacent one another.
Claim 2
Dependent Claim
374 words
A hydromechanical transmission, comprising: (a) 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; (b) a hydraulic power transmission mechanism having a pair of hydraulic pump/motors including a first fixed displacement pump/motor and a second variable displacement pump/motor, wherein an input/output end of said first pump/motor is directly connected to said second input/output end of said differential mechanism, and an input/output end of said second pump/motor is connected to said third input/output end of said differential mechanism through a first pair of meshing gears, wherein the input/output ends of the first and second pump/motors are disposed on the same side of said hydraulic power transmission mechanism, such that said pump/motors cooperate with one another to constitute variable-speed hydraulic power transmission lines; and (c) a mode selector mechanism for selecting 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 wherein said differential mechanism is a planetary gear train, and the input/output end of said first pump/motor is directly connected to an output shaft of a sun gear of said planetary gear train, and wherein the input/output end of said second pump/motor is connected through said first pair of meshing gears to a ring gear of said planetary gear train, and further wherein the sun gear of said first mechanical transfer line is connected to a low speed clutch, for connecting to the output of said hydromechanical transmission, through a second pair of meshing gears, and said second mechanical transfer line is connected to a high speed clutch, for connecting to the output of said hydromechanical transmission, by a third pair of meshing gears, such that said low and high speed clutches are connected adjacent one another and in-line on an output shaft of the output of said hydromechanical transmission, and also such that said second and third pairs of meshing gears are also positioned adjacent one another.
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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) | 1992-03-20 | 1992-09-19 | 1993-03-21 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1996-03-20 | 1996-09-19 | 1997-03-21 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 2000-03-20 | 2000-09-19 | 2001-03-21 | $7700.00 | Window Closed / Lapsed |