US3820418A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Planetary gear transmission for automotive vehicles
Assignee: ZF Friedrichshafen AG
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Filing: 1972-08-21
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Granted: 1974-06-28
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Expires: 1992-08-21
Abstract
Abstract An automotive transmission has three cascaded planetary gear trains, the first two gear trains having two interconnected or unitary sun gears and further having two interconnected or unitary ring gears rigid with the planet carrier of the third gear train and with an output shaft. A first clutch K1 connects an input shaft with the second planet carrier in any of four forward speeds while a second clutch K2 connects that shaft with the two paired sun gears in fourth gear (direct drive) and in either of two reverse speeds. Three brakes B1, B2, B3 serve to arrest the two paired sun gears, the first planet carrier or the third ring gear. The first planet carrier supports one set of planet gears whereas the second planet carrier supports two sets of planet gears meshing with each other.
Inventors
- 👤 A Ott
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-27 23:17
CPC Classifications
F; F16; F16H; F16H3/00; F16H3/44; F16H3/62; F16H3/66; F16H3/666; F16H2200/00; F16H2200/003; F16H2200/0043; F16H2200/0082; F16H2200/0086; F16H2200/20; F16H2200/2002; F16H2200/201
Claims Analysis
Total Claims: 5
Claim 1
Independent Claim
356 words
An automotive transmission for providing a plurality of speed ratios between an engine-driven input shaft and an output shaft, comprising: a first planetary gear train which a first sun gear, a first ring gear and a first planet carrier having a first planet gear in driving engagement with said first sun and ring gears; a second planetary gear train with a second sun gear, a second ring gear and a second planet carrier having a pair of intermeshing second planet gears in driving engagement with said second sun gear and said second ring gear, respectively, said first sun gear being coaxial and rigid with said second sun gear, said first ring gear being coaxial and rigid with said second ring gear and fixedly connected with said output shaft; a third planetary gear train with a third sun gear, a third ring gear and a third planet carrier having a third planet gear in driving engagement with said third ring and sun gears, said third sun gear being rigid with said second planet carrier, said third planet carrier being rigid with said output shaft; first clutch means actuatable for operatively coupling said input shaft with said second planet carrier to help establish a first, a second, a third and a fourth position representing different forward speed ratios of said shafts; second clutch means actuatable for operatively coupling said input shaft with said first and second sun gears to establish said fourth position in the actuated state of such first clutch means; first brake means actuatable for arresting said first and second sun gears to establish said third position in the actuated state of said first clutch means; second brake means actuatable for arresting said first planet carrier to establish said second position in the actuated state of said first clutch means; and third brake means actuatable for arresting said third ring gear to establish said first position in the actuated state of said first clutch means, said third brake means being also actuatable jointly with said clutch means in the unactuated state of said first clutch means to establish a fifth position representing an additional speed ratio.
Claim 2
Dependent Claim
356 words
An automotive transmission for providing a plurality of speed ratios between an engine-driven input shaft and an output shaft, comprising: a first planetary gear train which a first sun gear, a first ring gear and a first planet carrier having a first planet gear in driving engagement with said first sun and ring gears; a second planetary gear train with a second sun gear, a second ring gear and a second planet carrier having a pair of intermeshing second planet gears in driving engagement with said second sun gear and said second ring gear, respectively, said first sun gear being coaxial and rigid with said second sun gear, said first ring gear being coaxial and rigid with said second ring gear and fixedly connected with said output shaft; a third planetary gear train with a third sun gear, a third ring gear and a third planet carrier having a third planet gear in driving engagement with said third ring and sun gears, said third sun gear being rigid with said second planet carrier, said third planet carrier being rigid with said output shaft; first clutch means actuatable for operatively coupling said input shaft with said second planet carrier to help establish a first, a second, a third and a fourth position representing different forward speed ratios of said shafts; second clutch means actuatable for operatively coupling said input shaft with said first and second sun gears to establish said fourth position in the actuated state of such first clutch means; first brake means actuatable for arresting said first and second sun gears to establish said third position in the actuated state of said first clutch means; second brake means actuatable for arresting said first planet carrier to establish said second position in the actuated state of said first clutch means; and third brake means actuatable for arresting said third ring gear to establish said first position in the actuated state of said first clutch means, said third brake means being also actuatable jointly with said clutch means in the unactuated state of said first clutch means to establish a fifth position representing an additional speed ratio.
Claim 3
Dependent Claim
20 words
A transmission as defined in claim 1 wherein said first, second and third ring gears have equal numbers of teeth.
Claim 4
Dependent Claim
42 words
A transmission as defined in claim 1 wherein said second brake means is actuatable in the actuated state of said second clutch means and in the unactuated state of said first clutch means to establish a sixth position with reverse speed ratio.
Claim 5
Dependent Claim
16 words
A transmission as defined in claim 1 wherein said additional speed ratio is of negative sign.
References Cited (Backward Citations)
No citation records indexed.
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1977-06-27 | 1977-12-27 | 1978-06-28 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1981-06-27 | 1981-12-27 | 1982-06-28 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1985-06-27 | 1985-12-27 | 1986-06-28 | $7700.00 | Window Closed / Lapsed |