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US5380257A Expired / Lapsed US ⏱️ 0.0 years remaining

Electrohydraulic control device for a drive train of a vehicle

Assignee: Caterpillar Inc
•
Filing: 1993-03-25
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Granted: 1995-01-10
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Expires: 2013-03-25
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Abstract

Abstract An electrohydraulic control device for a drive train of a vehicle is provided. The drive train includes an engine, a transmission, a source of pressurized fluid, and an input clutch connected between the engine and the transmission. The control device senses the rotational output speed of the engine and responsively engages and disengages the input clutch as a function of the engine speed.

Inventors

  • 👤 Michael F. Coffman
  • 👤 Paul E. Jantz

Bibliographic Details

Application Number —
Jurisdiction US
Data Source google_patents
Last Synchronized 2026-10-30 10:42
CPC Classifications
F; F16; F16D; F16D48/00; F16D48/06; B; B60; B60W; B60W30/00; B60W30/18; B60W30/18009; B60W30/18063; F16D48/066; F16H; F16H59/00; F16H59/02; F16H59/04; F16H59/044; B60W2510/00; B60W2510/06; B60W2510/0638; F16D2500/00; F16D2500/10; F16D2500/104; F16D2500/10406; F16D2500/10412; F16D2500/30; F16D2500/306; F16D2500/3067; F16D2500/70; F16D2500/702; F16D2500/70205; F16D2500/70217; F16D2500/70252; F16D2500/7027; F16D2500/704; F16D2500/70402; F16D2500/70406; F16H59/0217; F16H59/36; F16H59/44

Claims Analysis

Total Claims: 2
Claim 1
Independent Claim 209 words
An electrohydraulic control device for a drive train of a vehicle including an engine, a transmission, a source of pressurized fluid, and an input clutch drivingly connected between the engine and the transmission, comprising: means for sensing the rotational output speed of the engine and responsively producing an engine speed signal; valve means for controllably directing fluid under pressure from the source to the input clutch to controllably engage and disengage the input clutch; and electronic control module means for receiving said engine speed signal and controllably actuating said valve means as a function of said engine speed signal, for comparing said engine speed signal with a first predetermined threshold and responsively actuating said valve means to maintain a first predetermined pressure within the input clutch in response to said engine speed signal being below said first predetermined threshold, for comparing said engine speed signal with a second predetermined threshold and responsively actuating said valve means to maintain a second predetermined pressure within the input clutch in response to said engine speed signal being above said second predetermined threshold, and for modulating pressure within the input clutch between said first and second predetermined pressures in response to said engine speed signal being between said first and second predetermined thresholds.
Claim 2
Dependent Claim 209 words
An electrohydraulic control device for a drive train of a vehicle including an engine, a transmission, a source of pressurized fluid, and an input clutch drivingly connected between the engine and the transmission, comprising: means for sensing the rotational output speed of the engine and responsively producing an engine speed signal; valve means for controllably directing fluid under pressure from the source to the input clutch to controllably engage and disengage the input clutch; and electronic control module means for receiving said engine speed signal and controllably actuating said valve means as a function of said engine speed signal, for comparing said engine speed signal with a first predetermined threshold and responsively actuating said valve means to maintain a first predetermined pressure within the input clutch in response to said engine speed signal being below said first predetermined threshold, for comparing said engine speed signal with a second predetermined threshold and responsively actuating said valve means to maintain a second predetermined pressure within the input clutch in response to said engine speed signal being above said second predetermined threshold, and for modulating pressure within the input clutch between said first and second predetermined pressures in response to said engine speed signal being between said first and second predetermined thresholds.

References Cited (Backward Citations)

US3074524A Cited
US3831726A Cited
US3862676A Cited
US3938631A Cited
US4718525A Cited
US5022287A Cited
US5040648A Cited

USPTO Annuity & Maintenance Windows

Annuity Stage Window Opens Payment Deadline Surcharge Period Until Estimated Fee Status
3.5 Years (Year 4) 1998-01-09 1998-07-11 1999-01-10 $2000.00 Window Closed / Lapsed
7.5 Years (Year 8) 2002-01-09 2002-07-11 2003-01-10 $3760.00 Window Closed / Lapsed
11.5 Years (Year 12) 2006-01-09 2006-07-11 2007-01-10 $7700.00 Window Closed / Lapsed

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