US3672478A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Hydraulically operated wet-type friction clutch
Assignee: ZF Friedrichshafen AG
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Filing: 1971-05-11
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Granted: 1972-06-27
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Expires: 1991-05-11
Abstract
Abstract The release mechanism of a wet-type friction clutch is actuated by a piston which divides the cavity of a cylinder into two compartments. One compartment is connected to an oil pump through a control valve which either admits high-pressure oil to the compartment or vents the compartment to a sump. The other compartment is continuously supplied with oil under lower pressure by the sump pump through a pressure reducing valve, and the oil flows from the other compartment to a nozzle which directs it toward the engageable friction faces of the driving and driven clutch members. When the high-pressure compartment is vented, the oil in the other compartment acts on the piston to retract the clutch release bearing from the release levers or the diaphragm spring of the clutch.
Inventors
- 👤 Hans-Walter Riese
- 👤 Gerhard Friedrich
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-01 19:03
CPC Classifications
F; F16; F16D; F16D25/00; F16D25/12; F16D25/123; F16D13/00; F16D13/58; F16D13/72; F16D25/08; F16D25/082; F16D25/087; F16D25/083
Claims Analysis
Total Claims: 10
Claim 1
Independent Claim
271 words
In a hydraulically operated, wet-type friction clutch arrangement including a driving clutch member, a driven clutch member, said members being mounted for rotation about a common axis and having respective friction faces, clutch spring means biasing said members toward torque-transmitting engagement of said faces, clutch release means for disengaging said faces against the biasing force of said spring means, hydraulically operated actuating means for actuating said clutch release means, said actuating means including a source of hydraulic fluid under pressure, a cylinder member having an axis and defining a cavity therein, a piston member axially movable in said cavity and dividing the same into two compartments, connecting means connecting said piston member to said clutch release means for disengaging said faces when said piston member moves in said cavity in one axial direction, said faces being engaged by said clutch spring means when said piston member moves in the other axial direction, and flow control means interposed between one of said compartments and said source of hydraulic fluid and alternatively operative for admitting said fluid to said one compartment and for thereby moving said piston member in said one direction, and for releasing the admitted fluid from said one compartment, a source of cooling oil under a pressure lower than the pressure of said fluid, and nozzle means communicating with said source of cooling oil for discharging said oil toward said faces, the improvement which comprises: conduit means connecting said source of cooling oil to the other compartment in said cavity and to said nozzle means, whereby said cooling oil tends to move said piston member in said other axial direction.
Claim 2
Dependent Claim
271 words
In a hydraulically operated, wet-type friction clutch arrangement including a driving clutch member, a driven clutch member, said members being mounted for rotation about a common axis and having respective friction faces, clutch spring means biasing said members toward torque-transmitting engagement of said faces, clutch release means for disengaging said faces against the biasing force of said spring means, hydraulically operated actuating means for actuating said clutch release means, said actuating means including a source of hydraulic fluid under pressure, a cylinder member having an axis and defining a cavity therein, a piston member axially movable in said cavity and dividing the same into two compartments, connecting means connecting said piston member to said clutch release means for disengaging said faces when said piston member moves in said cavity in one axial direction, said faces being engaged by said clutch spring means when said piston member moves in the other axial direction, and flow control means interposed between one of said compartments and said source of hydraulic fluid and alternatively operative for admitting said fluid to said one compartment and for thereby moving said piston member in said one direction, and for releasing the admitted fluid from said one compartment, a source of cooling oil under a pressure lower than the pressure of said fluid, and nozzle means communicating with said source of cooling oil for discharging said oil toward said faces, the improvement which comprises: conduit means connecting said source of cooling oil to the other compartment in said cavity and to said nozzle means, whereby said cooling oil tends to move said piston member in said other axial direction.
Claim 3
Dependent Claim
59 words
In an arrangement as set forth in claim 1, said conduit means including a first conduit connecting said source of cooling oil to the other compartment in said cavity and a second conduit connecting said other compartment to said nozzle means for passage of said cooling oil from said source thereof through said other compartment toward said nozzle means.
Claim 4
Dependent Claim
33 words
In an arrangement as set forth in claim 2, said first and second conduits constituting the only connection between said source of cooling oil and said nozzle means, said connection being permanently open.
Claim 5
Dependent Claim
39 words
In an arrangement as set forth in claim 1, wherein a clutch shaft is coaxially secured to said driven clutch member for joint rotation, said piston member and said cylinder member being tubular and coaxially enveloping said clutch shaft.
Claim 6
Dependent Claim
41 words
In an arrangement as set forth in claim 4, said sources including a common sump and a common oil pump communicating with said sump for drawing liquid from the same, said liquid constituting both said hydraulic fluid and said cooling oil.
Claim 7
Dependent Claim
29 words
In an arrangement as set forth in claim 5, a pressure reducing valve in said conduit means for reducing the pressure of said cooling oil to said lower pressure.
Claim 8
Dependent Claim
27 words
In an arrangement as set forth in claim 6, said flow control means including a control valve communicating with said one compartment, said pump, and said sump.
Claim 9
Dependent Claim
89 words
In an arrangement as set forth in claim 4, said conduit means including a first conduit connecting said source of cooling oil to said other compartment in said cavity, and a second conduit connecting said other compartment to said nozzle means for passage of said cooling oil from said source thereof through said compartment toward said nozzle means, a part of said second conduit being elongated axially between said piston member said clutch shaft, an axially terminal portion of said second conduit constituting a portion of said nozzle means.
Claim 10
Dependent Claim
91 words
In an arrangement as set forth in claim 4, said conduit means including a first conduit connecting said source of cooling oil to said other compartment in said cavity, and a second conduit connecting said other compartment to said nozzle means for passage of said cooling oil from said source thereof through said compartment toward said nozzle means, a part of said second conduit being constituted by an axial bore in said clutch shaft, and said nozzle means including a radial bore in said clutch shaft communicating with said axial bore.
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) | 1975-06-27 | 1975-12-27 | 1976-06-27 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1979-06-27 | 1979-12-27 | 1980-06-27 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1983-06-27 | 1983-12-27 | 1984-06-27 | $7700.00 | Window Closed / Lapsed |