US3926075A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Vehicle automatic transmission having push start capability
Assignee: Mack Trucks Inc
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Filing: 1974-10-18
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Granted: 1975-12-16
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Expires: 1994-10-18
Abstract
Abstract An auxiliary transmission oil pump, driven from the output shaft of a vehicle automatic transmission, bypasses the transmission automatic control logic and supplies pressurized oil to operate the appropriate clutch or clutches to provide a suitable transmission ratio during a push or tow start of the vehicle. The output of the auxiliary pump is controlled by the vehicle direction control valve so that push starting may be accomplished only when the control valve is in the ''''forward'''' position. Once the engine starts, the main transmission oil pump absorbs the flow from the auxiliary pump so that the transmission automatic control logic directs the operation of the transmission.
Inventors
- 👤 Victor Kronstadt
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-30 05:11
CPC Classifications
B; B60; B60W; B60W10/00; B60W10/04; B60W10/06; B60W10/10; B60W10/101; B60W10/103; B60W10/11; B60W30/00; B60W30/18; F; F16; F16H; F16H61/00; F16H61/0021; F16H61/0025; F16H61/0031; F16H61/12
Claims Analysis
Total Claims: 9
Claim 1
Independent Claim
179 words
A vehicle automatic transmission comprising an input shaft adapted to be coupled to the vehicle engine, an output shaft adapted to be coupled to the driven wheels of the vehicle, drive means connecting the input shaft to the output shaft with an adjustable transmission ratio, automatic control means for adjusting the transmission ratio of the drive means, a first pump adapted to be driven by the vehicle engine for delivering pressurized liquid to the automatic control means, means for selecting a predetermined transmission ratio of the drive means, a second pump driven by the output shaft for delivering pressurized liquid to energize the selecting means so as to select the predetermined transmission ratio, and means for selectively communicating the output of the second pump with the selecting means independently of the automatic control means, whereby the vehicle engine may be started by moving the vehicle so as to drive the engine from the wheels at the predetermined transmission ratio, the automatic control means exerting no control over the transmission ratio of the drive means before the engine is started.
Claim 2
Dependent Claim
179 words
A vehicle automatic transmission comprising an input shaft adapted to be coupled to the vehicle engine, an output shaft adapted to be coupled to the driven wheels of the vehicle, drive means connecting the input shaft to the output shaft with an adjustable transmission ratio, automatic control means for adjusting the transmission ratio of the drive means, a first pump adapted to be driven by the vehicle engine for delivering pressurized liquid to the automatic control means, means for selecting a predetermined transmission ratio of the drive means, a second pump driven by the output shaft for delivering pressurized liquid to energize the selecting means so as to select the predetermined transmission ratio, and means for selectively communicating the output of the second pump with the selecting means independently of the automatic control means, whereby the vehicle engine may be started by moving the vehicle so as to drive the engine from the wheels at the predetermined transmission ratio, the automatic control means exerting no control over the transmission ratio of the drive means before the engine is started.
Claim 3
Dependent Claim
51 words
An automatic transmission according to claim 1, wherein a plurality of transmission ratios may be selected by the automatic control means, and the predetermined transmission ratio selected in response to pressurized liquid from the second pump is one of the transmission ratios that may be selected by the automatic control means.
Claim 4
Dependent Claim
80 words
An automatic transmission according to claim 2, wherein the output of the second pump is also communicated with the input of the first pump, and the displacement of the first pump exceeds that of the second pump such that the output of the second pump is sufficiently diverted to the first pump when the engine is started so that the selecting means is automatically de-energized and the transmission ratio of the drive means is controlled by the automatic control means.
Claim 5
Dependent Claim
44 words
An automatic transmission according to claim 3, including a plurality of clutch means responsive to the automatic control means for selecting the plurality of transmission ratios, and wherein the means for selecting the predetermined transmission ratio includes at least one of the clutch means.
Claim 6
Dependent Claim
39 words
An automatic transmission according to claim 2, including a plurality of clutch means responsive to the automatic control means for selecting the plurality of transmission ratios, and wherein the means for selecting the predetermined transmission ratio includes clutch means.
Claim 7
Dependent Claim
31 words
An automatic transmission according to claim 5, wherein the clutch means for selecting the predetermined transmission ratio includes at least one of the clutch means responsive to the automatic control means.
Claim 8
Dependent Claim
85 words
An automatic transmission according to claim 1, including manual direction control valve means having forward, neutral and reverse positions, the manual control valve means communicating the output of the first pump with the automatic control means when in the forward position, and the manual control valve means including the means for selectively communicating the output of the second pump with the selecting means such that the second pump is communicated with the selecting means when the manual control valve means is in the forward position.
Claim 9
Dependent Claim
80 words
An automatic transmission according to claim 7, wherein the output of the second pump is also communicated with the input of the first pump, and the displacement of the first pump exceeds that of the second pump such that the output of the second pump is sufficiently diverted to the first pump when the engine is started so that the selecting means is automatically de-energized and the transmission ratio of the drive means is controlled by the automatic control means.
References Cited (Backward Citations)
US3654758A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1978-12-15 | 1979-06-16 | 1979-12-16 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1982-12-15 | 1983-06-16 | 1983-12-16 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1986-12-15 | 1987-06-16 | 1987-12-16 | $7700.00 | Window Closed / Lapsed |