Patent US5437204A successfully refreshed from Google Patents.
US5437204A
Expired / Lapsed
US
⏱️ 0.0 years remaining
System for selecting the operating ranges of an automatic transmission
Assignee: Ford Global Technologies LLC
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Filing: 1993-12-20
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Granted: 1995-08-01
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Expires: 2013-12-20
Abstract
Abstract A system for directing line pressure alternately to a forward drive circuit and a reverse drive circuit includes three solenoid-operated select valves that direct pressure from a line pressure source to a reverse drive select valve, a forward drive select valve, reverse drive select valve, a range select switch assembly, pressure switches, and two coaxial range control valves. The two drive select valves are interconnected to form a hydraulic latch whose outputs are connected to the range control valve such that either the forward drive friction elements are pressurized, the reverse drive friction elements are pressurized, or none of the friction elements are pressurized.
Inventors
- 👤 Dennis W. Person
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-05 22:44
CPC Classifications
F; F16; F16H; F16H59/00; F16H59/02; F16H59/08; F16H59/10; F16H59/105; F16H61/00; F16H61/02; F16H61/0202; F16H61/0204; F16H61/0246; F16H61/0251; F16H2061/026; F16H61/0262; F16H61/0276; F16H2061/0288; Y; Y10; Y10T; Y10T74/00; Y10T74/19; Y10T74/19219; Y10T74/19251
Claims Analysis
Total Claims: 11
Claim 1
Independent Claim
175 words
A system for producing operating ranges of an automatic transmission having hydraulically actuated forward drive and reverse drive friction elements engaged and released alternately to produce a forward drive range, reverse drive range and neutral range, comprising: a range selector moveable manually among positions corresponding to the operating ranges of the transmission; a fluid pressure source; hydraulic circuit means including first, second and third solenoid-operated control valves, a forward select valve and reverse select valve controlled by the first, second and third solenoid-operated control valves, for opening and closing communication between the pressure source and friction elements in response to the position of the range selector; an electric power source; range select switch means for selectively connecting and disconnecting the electric power source and said solenoids in response to the position of the range selector; pressure switch means for disconnecting the electric power source and the first solenoid when the forward drive friction elements are pressurized, and for disconnecting the electric power source and the second solenoid when the reverse drive friction elements are pressurized.
Claim 2
Independent Claim
175 words
A system for producing operating ranges of an automatic transmission having hydraulically actuated forward drive and reverse drive friction elements engaged and released alternately to produce a forward drive range, reverse drive range and neutral range, comprising: a range selector moveable manually among positions corresponding to the operating ranges of the transmission; a fluid pressure source; hydraulic circuit means including first, second and third solenoid-operated control valves, a forward select valve and reverse select valve controlled by the first, second and third solenoid-operated control valves, for opening and closing communication between the pressure source and friction elements in response to the position of the range selector; an electric power source; range select switch means for selectively connecting and disconnecting the electric power source and said solenoids in response to the position of the range selector; pressure switch means for disconnecting the electric power source and the first solenoid when the forward drive friction elements are pressurized, and for disconnecting the electric power source and the second solenoid when the reverse drive friction elements are pressurized.
Claim 3
Dependent Claim
58 words
The system of claim 1 wherein the hydraulic circuit means vents the friction elements when the range selector is in the neutral range position, pressurizes the forward drive range friction elements when the range selector is in the forward range position, and pressurizes the reverse drive friction elements when the range selector is in the reverse range position.
Claim 4
Dependent Claim
106 words
The system of claim 1 wherein the range select switch means further comprises: neutral switch means for connecting the electric power source and said third solenoid when the range selector is in the reverse or forward drive range position, disconnecting the electric power source and said first solenoid when the range selector is in the neutral drive range position, potentially connecting the electric power source and said second solenoid when the range selector is in the neutral drive range position, and disconnecting the electric power source and said potential connection when the range selector is in the reverse drive range position or forward drive range position.
Claim 5
Dependent Claim
99 words
The system of claim 1 wherein the range select switch means further comprises: forward-reverse switch means for connecting the electric power source and said first solenoid when the range selector is in the forward drive range position, disconnecting the electric power source and said first solenoid when the range selector is in the reverse drive range position, potentially connecting the electric power source and said second solenoid when the range selector is in the reverse drive range position, and disconnecting the electric power source and said potential connection when the range selector is in the forward drive range position.
Claim 6
Dependent Claim
65 words
The system of claim 1 wherein the range select switch means further comprises a low switch means for potentially connecting the electric power source and said second solenoid when the range selector is in the low drive range position, and for disconnecting the electric power source and said potential connection when the range selector is in a position other than the low drive range position.
Claim 7
Dependent Claim
193 words
The system of claim 1 wherein the range select switch means further comprises: neutral switch means for connecting the electric power source and said third solenoid when the range selector is in the reverse or forward drive range position, disconnecting the electric power source and said first solenoid when the range selector is in the neutral drive range position, potentially connecting the electric power source and said second solenoid when the range selector is in the neutral drive range position, and disconnecting the electric power source and said potential connection when the range selector is in the reverse drive range position or forward drive range position; and forward-reverse switch means for connecting the electric power source and said first solenoid when the range selector is in the forward drive range position, disconnecting the electric power source and said first solenoid when the range selector is in the reverse drive range position, potentially connecting the electric power source and said second solenoid when the range selector is in the reverse drive range position, and disconnecting the electric power source and said potential connection when the range selector is in the forward drive range position.
Claim 8
Dependent Claim
71 words
The system of claim 1 wherein pressure switch means comprises: forward pressure switch means for connecting and disconnecting the electric power source and said first solenoid in response to the magnitude of pressure directed to the forward drive friction elements; and reverse pressure switch means for connecting and disconnecting the electric power source and said second solenoid in response to the magnitude of pressure directed to the reverse drive friction elements.
Claim 9
Dependent Claim
50 words
The system of claim 1 wherein the transmission includes low drive friction elements and the pressure switch means further comprises low pressure switch means for connecting and disconnecting the electric power source and said second solenoid in response to the magnitude of pressure directed to the low drive friction elements.
Claim 10
Independent Claim
419 words
A system for producing operating ranges of an automatic transmission having hydraulically actuated forward drive and reverse drive friction elements engaged and released alternately to produce a forward drive range, reverse drive range and neutral range, comprising: a range selector moveable manually among positions corresponding to the operating ranges of the transmission; a fluid pressure source; hydraulic circuit means including first, second and third solenoid-operated control valves, a forward select valve and reverse select valve controlled by the first, second and third solenoid-operated control valves, for opening and closing communication between the pressure source and friction elements in response to the position of the range selector; an electric power source; range select switch means for selectively connecting and disconnecting the electric power source and said solenoids in response to the position of the range selector, including neutral switch means for connecting the electric power source and said third solenoid when the range selector is in the reverse or forward drive range position, disconnecting the electric power source and said first solenoid when the range selector is in the neutral drive range position, potentially connecting the electric power source and said second solenoid when the range selector is in the neutral drive range position, and disconnecting the electric power source and said potential connection when the range selector is in the reverse drive range position or forward drive range position; and forward-reverse switch means for connecting the electric power source and said first solenoid when the range selector is in the forward drive range position, disconnecting the electric power source and said first solenoid when the range selector is in the reverse drive range position, potentially connecting the electric power source and said second solenoid when the range selector is in the reverse drive range position, and disconnecting the electric power source and said potential connection when the range selector is in the forward drive range position; and pressure switch means for disconnecting the electric power source and the first solenoid when the forward drive friction elements are pressurized, and for disconnecting the electric power source and the second solenoid when the reverse drive friction elements are pressurized, including forward pressure switch means for connecting and disconnecting the electric power source and said first solenoid in response to the magnitude of pressure directed to the forward drive friction elements, and reverse pressure switch means for connecting and disconnecting the electric power source and said second solenoid in response to the magnitude of pressure directed to the reverse drive friction elements.
Claim 11
Independent Claim
419 words
A system for producing operating ranges of an automatic transmission having hydraulically actuated forward drive and reverse drive friction elements engaged and released alternately to produce a forward drive range, reverse drive range and neutral range, comprising: a range selector moveable manually among positions corresponding to the operating ranges of the transmission; a fluid pressure source; hydraulic circuit means including first, second and third solenoid-operated control valves, a forward select valve and reverse select valve controlled by the first, second and third solenoid-operated control valves, for opening and closing communication between the pressure source and friction elements in response to the position of the range selector; an electric power source; range select switch means for selectively connecting and disconnecting the electric power source and said solenoids in response to the position of the range selector, including neutral switch means for connecting the electric power source and said third solenoid when the range selector is in the reverse or forward drive range position, disconnecting the electric power source and said first solenoid when the range selector is in the neutral drive range position, potentially connecting the electric power source and said second solenoid when the range selector is in the neutral drive range position, and disconnecting the electric power source and said potential connection when the range selector is in the reverse drive range position or forward drive range position; and forward-reverse switch means for connecting the electric power source and said first solenoid when the range selector is in the forward drive range position, disconnecting the electric power source and said first solenoid when the range selector is in the reverse drive range position, potentially connecting the electric power source and said second solenoid when the range selector is in the reverse drive range position, and disconnecting the electric power source and said potential connection when the range selector is in the forward drive range position; and pressure switch means for disconnecting the electric power source and the first solenoid when the forward drive friction elements are pressurized, and for disconnecting the electric power source and the second solenoid when the reverse drive friction elements are pressurized, including forward pressure switch means for connecting and disconnecting the electric power source and said first solenoid in response to the magnitude of pressure directed to the forward drive friction elements, and reverse pressure switch means for connecting and disconnecting the electric power source and said second solenoid in response to the magnitude of pressure directed to the reverse drive friction elements.
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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) | 1998-07-31 | 1999-01-30 | 1999-08-01 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 2002-07-31 | 2003-01-30 | 2003-08-01 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 2006-07-31 | 2007-01-30 | 2007-08-01 | $7700.00 | Window Closed / Lapsed |