US3735646A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Hydrostatic transmission mechanism
Assignee: Borg Warner Corp
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Filing: 1971-05-28
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Granted: 1973-05-29
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Expires: 1991-05-28
Abstract
Abstract A combined mechanical and hydrostatic transmission having the sun gear of the planetary gear set driven by the input shaft the carrier of the planetary gear set driving the output shaft and a pair of hydraulic units, one of which has relatively rotating elements connected to two of the planetary gear set elements, namely, the planetary carrier and the ring gear, the other hydraulic unit being in fluid communication with the first hydraulic unit and being connected between the fixed element of the case and the ring gear. Both hydraulic units have variable displacement whereby with one of said hydraulic units being at a given displacement, and the other hydraulic unit at zero displacement the ring gear of the planetary gear set will be locked against rotation whereby the full reduction ratio of the planetary gear set is utilized and, in the situation where the said one hydraulic unit is at zero displacement, and the first hydraulic unit has a given displacement, the first hydraulic unit will lock up the planetary carrier and the ring gear to provide a 1:1 direct drive. In addition, infinitely variable speed ratios are available by having the pair of hydraulic units in various displacement positions relative to the above limits whereby a full range of speed ratios is available between the full reduction ratio of the planetary gear set and a 1:1 direct drive.
Inventors
- 👤 R Roberts
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-30 01:02
CPC Classifications
F; F16; F16H; F16H47/00; F16H47/02; F16H47/04; F16H37/00; F16H37/02; F16H37/06; F16H37/08; F16H37/0833; F16H37/084; F16H2037/088
Claims Analysis
Total Claims: 12
Claim 1
Independent Claim
157 words
A transmission mechanism including a variable ratio gear set, a pair of hydraulic units for said transmission and each having rotational elements, one of said hydraulic units including a variable angle swash plate, an input shaft and an output shaft for said transmission, said input shaft connected to a first gear element of said gear set and said output shaft connected to a second gear element of said gear set, a third gear element of said gear set being operatively connected to a rotational element of each of said pair of hydraulic units, at least one of said hydraulic units having a variable displacement, said swash plate rotating with one of said gear elements and including variable means actuatable to vary the angle of said swash plate and a fixed reaction element connected to said hydraulic units whereby infinitely variable drive ratios may be obtained by varying the volume of at least one of said hydraulic units.
Claim 2
Dependent Claim
157 words
A transmission mechanism including a variable ratio gear set, a pair of hydraulic units for said transmission and each having rotational elements, one of said hydraulic units including a variable angle swash plate, an input shaft and an output shaft for said transmission, said input shaft connected to a first gear element of said gear set and said output shaft connected to a second gear element of said gear set, a third gear element of said gear set being operatively connected to a rotational element of each of said pair of hydraulic units, at least one of said hydraulic units having a variable displacement, said swash plate rotating with one of said gear elements and including variable means actuatable to vary the angle of said swash plate and a fixed reaction element connected to said hydraulic units whereby infinitely variable drive ratios may be obtained by varying the volume of at least one of said hydraulic units.
Claim 3
Dependent Claim
42 words
A transmission mechanism as claimed in claim 1 wherein said variable means comprises an annular element rotating with said swash plate and having at least one fluid responsive actuator therein changing the angle of said swash plate in response to fluid pressure.
Claim 4
Dependent Claim
54 words
A transmission mechanism as claimed in claim 2 wherein said annular element includes a pair of said actuators, one of said actuators acting in response to fluid pressure to move the swash plate in a first direction and the other actuator responding to fluid pressure to move the swash plate in the opposite direction.
Claim 5
Dependent Claim
47 words
A transmission mechanism as claimed in claim 3 wherein said actuator includes a fluid responsive piston having a pivotal sector member connected thereto and drivingly connected to the swash plate for pivoting in response to movement of the piston to vary the angle of said swash plate.
Claim 6
Dependent Claim
124 words
A transmission mechanism including a planetary gear set including a sun gear, an annulus gear, and a planetary carrier, a pair of hydraulic units for said transmission and each having rotational elements, an input shaft and an output shaft for said transmission, said input shaft connected to said sun gear, said output shaft connected to said planetary carrier of said gear set, said annulus gear being operatively connected to a rotational element of each of said pair of hydraulic units, at least one of said hydraulic units having a variable displacement and a fixed reaction element connected to said hydraulic units whereby infinitely variable drive ratios through said transmission may be obtained by varying the volume of at least one of said hydraulic units.
Claim 7
Dependent Claim
124 words
A transmission mechanism including a planetary gear set including a sun gear, an annulus gear, and a planetary carrier, a pair of hydraulic units for said transmission and each having rotational elements, an input shaft and an output shaft for said transmission, said input shaft connected to said sun gear, said output shaft connected to said planetary carrier of said gear set, said annulus gear being operatively connected to a rotational element of each of said pair of hydraulic units, at least one of said hydraulic units having a variable displacement and a fixed reaction element connected to said hydraulic units whereby infinitely variable drive ratios through said transmission may be obtained by varying the volume of at least one of said hydraulic units.
Claim 8
Dependent Claim
18 words
A transmission mechanism as claimed in claim 5 wherein both of said hydraulic units have a variable displacement.
Claim 9
Dependent Claim
26 words
A transmission mechanism as claimed in claim 5 wherein said planetary carrier element is drivingly connected to a rotational element of one of said hydraulic units.
Claim 10
Dependent Claim
36 words
A transmission mechanism as claimed in claim 7 wherein said hydraulic units are of the axial piston rotary cylinder barrel type each having a swash plate and said rotational element comprising one of said swash plates.
Claim 11
Dependent Claim
29 words
A transmission mechanism as claimed in claim 5 wherein a 1:1 lockup condition will be established in said gear set with one of said hydraulic units at zero displacement.
Claim 12
Dependent Claim
35 words
A transmission mechanism as claimed in claim 5 wherein said annulus gear will be held stationary to establish a maximum gear ratio through said transmission when one of said hydraulic units is at zero displacement.
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) | 1976-05-28 | 1976-11-27 | 1977-05-29 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1980-05-28 | 1980-11-27 | 1981-05-29 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1984-05-28 | 1984-11-27 | 1985-05-29 | $7700.00 | Window Closed / Lapsed |