US4036342A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Inching valve with means preventing high pressure inching
Assignee: Caterpillar Industrial Inc
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Filing: 1976-06-28
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Granted: 1977-07-19
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Expires: 1996-06-28
Abstract
Abstract A pressure limiting arrangement is disclosed for automatically reestablishing full clutch engagement pressure to a hydraulic pressure actuated clutch of a vehicle whenever the operator, by the manipulation of an inching valve, attempts to slip the clutch above a predetermined partial engagement pressure and includes a mechanical biasing device connected to the inching valve and effective in overriding the manual control thereof to shift the valve to its full clutch engaging position, an actuator connected for effecting the disengagement of the biasing device to allow normal operation of the valve, and a control system to effect the selective operation of the actuator and including a first device responsive to a predetermined application of the manual control member of the valve to effect the initial disengagement of the biasing device and a second device responsive to the predetermined partial clutch engagement pressure to effect the reengagement of the mechanical biasing device.
Inventors
- 👤 David S. Finn
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-04 05:11
CPC Classifications
F; F16; F16D; F16D48/00; F16D48/06; F16D48/066; F16D2500/00; F16D2500/10; F16D2500/102; F16D2500/1026; F16D2500/104; F16D2500/10406; F16D2500/10412; F16D2500/11; F16D2500/1107; F16D2500/1112; F16D2500/30; F16D2500/302; F16D2500/3024; F16D2500/314; F16D2500/31406; F16D2500/31493; F16D2500/50; F16D2500/51; F16D2500/5104; F16D2500/70; F16D2500/704; F16D2500/70402; F16D2500/70406; F16D2500/7041; Y; Y10; Y10T; Y10T137/00; Y10T137/2496; Y10T137/2559; Y10T137/2574; Y10T137/2605; Y10T137/2607
Claims Analysis
Total Claims: 8
Claim 1
Independent Claim
170 words
In a control system for a hydraulic pressure actuated clutch including an inching valve variably shiftable between a full clutch engaging position and a clutch disengaging position and a manual control member connected for normally shifting the valve between said positions for controllably varying the clutch engaging pressure, a pressure limiting arrangement for automatically reestablishing full clutch engagement pressure to the clutch whenever partial clutch engagement pressure exceeds a predetermined level, said arrangement comprising: biasing means connected to said inching valve sufficient to shift the valve to its full clutch engaging position irrespective of the operation of the manual control apparatus; actuator means connected for disengaging said biasing means; and control means for selectively operating said actuator means and including first means responsive to the application of said manual control member to effect the disengagement of said baising means upon a predetermined application of said member, and second means responsive to said clutch engagement pressure for effecting the reengagement of the biasing means when said pressure exceeds a predetermined level.
Claim 2
Dependent Claim
170 words
In a control system for a hydraulic pressure actuated clutch including an inching valve variably shiftable between a full clutch engaging position and a clutch disengaging position and a manual control member connected for normally shifting the valve between said positions for controllably varying the clutch engaging pressure, a pressure limiting arrangement for automatically reestablishing full clutch engagement pressure to the clutch whenever partial clutch engagement pressure exceeds a predetermined level, said arrangement comprising: biasing means connected to said inching valve sufficient to shift the valve to its full clutch engaging position irrespective of the operation of the manual control apparatus; actuator means connected for disengaging said biasing means; and control means for selectively operating said actuator means and including first means responsive to the application of said manual control member to effect the disengagement of said baising means upon a predetermined application of said member, and second means responsive to said clutch engagement pressure for effecting the reengagement of the biasing means when said pressure exceeds a predetermined level.
Claim 3
Dependent Claim
12 words
The arrangement of claim 1 wherein said actuator means is a solenoid.
Claim 4
Dependent Claim
46 words
The arrangement of claim 2 wherein said first means is a mechanical switch mounted for actuation by said manual control member when said member is actuated beyond a position normally sufficient to modulate the clutch engagement pressure to a level at least below said predetermined level.
Claim 5
Dependent Claim
24 words
The arrangement of claim 3 wherein said second means is a pressure switch connected in communication with the fluid pressure for engaging said clutch.
Claim 6
Dependent Claim
47 words
The arrangement of claim 4 wherein said control means includes electrical circuit means including a source of electrical energy and means for interconnecting said source of electrical energy with said solenoid and said switches so that said solenoid is energized whenever either of said switches is closed.
Claim 7
Dependent Claim
131 words
The arrangement of claim 5 wherein said inching valve includes a reciprocably mounted valve spool having a first end portion and movable in one direction to effect the first position of the valve and in the opposite direction to effect the second position thereof; and wherein said mechanical biasing means includes an elongated stem extending from said first end portion of the valve spool and having a radially extending flange adjacent its distal end, a tubular sleeve slidably mounted about said stem and having a mating flange thereon for abutting said flange of the stem and a radially disposed shoulder thereabout, and a coil spring mounted between said shoulder of the sleeve and the inching valve for biasing said spool in said first direction through the abutting engagement of said flanges.
Claim 8
Dependent Claim
57 words
The arrangement of claim 6 wherein said solenoid is operatively connected to said sleeve for effecting the compression of said spring when said solenoid is energized so as to disengage the mating flange of the sleeve from the flange of the stem of the valve spool to permit the movement of the spool in said opposite direction.
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) | 1980-07-18 | 1981-01-17 | 1981-07-19 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1984-07-18 | 1985-01-17 | 1985-07-19 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1988-07-18 | 1989-01-17 | 1989-07-19 | $7700.00 | Window Closed / Lapsed |