Patent US4432444A successfully refreshed from Google Patents.
US4432444A
Expired / Lapsed
US
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Fluid friction clutch
Assignee: SUEDDEUTSCHE KUEHLERFABRIK JULIUS FR BEHR & Co KG GmbH
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Filing: 1981-03-12
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Granted: 1984-02-21
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Expires: 2001-03-12
Abstract
Abstract Disclosed is a fluid friction clutch, comprising a drive disk having at least one first working surface; a housing enclosing said drive disk and being mounted rotatably with respect thereto, the housing including at least one second working surface in spaced relationship with the first working surface to form a gap therebetween; a device for selectively introducing a fluid working medium into the gap; and a device for removing the fluid working medium from the gap, wherein the first and/or second working surfaces comprise roughened surfaces.
Inventors
- 👤 Kurt Hauser
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-02 07:31
CPC Classifications
F; F01; F01P; F01P7/00; F01P7/02; F01P7/04; F01P7/042; F16; F16D; F16D35/00; F16D35/02; F16D35/021; F16D35/022
Claims Analysis
Total Claims: 20
Claim 1
Independent Claim
116 words
A fluid friction clutch, comprising: a drive disk having at least one first working surface; a housing enclosing said drive disk and being mounted rotatably with respect thereto, said housing including at least one second working surface in spaced relationship with said first working surface to form a gap therebetween; means for selectively introducing a fluid working medium into said gap; and means for removing the fluid working medium from said gap wherein at least one of said first and second working surfaces comprises a roughened surface, said roughening providing a more uniform filling of the working gap thus reducing uncontrollable throwing of said working medium and fluctuations in r.p.m. as said working medium is introduced.
Claim 2
Dependent Claim
116 words
A fluid friction clutch, comprising: a drive disk having at least one first working surface; a housing enclosing said drive disk and being mounted rotatably with respect thereto, said housing including at least one second working surface in spaced relationship with said first working surface to form a gap therebetween; means for selectively introducing a fluid working medium into said gap; and means for removing the fluid working medium from said gap wherein at least one of said first and second working surfaces comprises a roughened surface, said roughening providing a more uniform filling of the working gap thus reducing uncontrollable throwing of said working medium and fluctuations in r.p.m. as said working medium is introduced.
Claim 3
Dependent Claim
21 words
A fluid friction clutch according to claim 1, wherein said roughened surfaces have mean roughness values of R a ≧5 μm.
Claim 4
Dependent Claim
21 words
A fluid friction clutch according to claim 2, wherein said roughened surfaces have mean roughness values of R a ≦2000 μm.
Claim 5
Dependent Claim
22 words
A fluid friction clutch according to claim 1, wherein said roughened surfaces have mean roughness values of 5 μm≦R a ≦50 μm.
Claim 6
Dependent Claim
15 words
A fluid friction clutch according to claim 1, wherein said roughened surfaces comprise metallic surfaces.
Claim 7
Dependent Claim
16 words
A fluid friction clutch according to claim 1, wherein said roughened surfaces comprise synthetic resinous surfaces.
Claim 8
Dependent Claim
18 words
A fluid friction clutch according to claim 1, wherein said working surfaces comprise surfaces roughened by shot blasting.
Claim 9
Dependent Claim
18 words
A fluid friction clutch according to claim 1, wherein said working surfaces comprise surfaces produced by rough turning.
Claim 10
Dependent Claim
22 words
A fluid friction clutch according to claim 8, wherein the radius of the turning grooves is from about 0.4 to 1.2 mm.
Claim 11
Dependent Claim
18 words
A fluid friction clutch according to claim 1, wherein said working surfaces comprise surfaces roughened by straight knurling.
Claim 12
Dependent Claim
18 words
A fluid friction clutch according to claim 1, wherein said working surfaces comprise surfaces produced by chemical treatment.
Claim 13
Dependent Claim
14 words
A fluid friction clutch according to claim 11, wherein said chemical treatment comprises etching.
Claim 14
Dependent Claim
23 words
A fluid friction clutch according to claim 1, wherein said working surfaces comprise surfaces produced by the casting process using suitably shaped molds.
Claim 15
Dependent Claim
22 words
A fluid friction clutch according to claim 1, wherein said working surfaces comprise surfaces produced by the application of a grainy coating.
Claim 16
Dependent Claim
21 words
Fluid friction clutch according to claim 1, wherein said working surfaces comprise surfaces produced by the application of a fibrous coating.
Claim 17
Dependent Claim
50 words
A fluid friction clutch according to claim 1, wherein said removing means comprises an annular surface arranged on said drive disk in an axially offset manner with respect to said first working surface and a baffle barrier arranged on the side of the housing opposite to said offset annular surface.
Claim 18
Dependent Claim
22 words
A fluid friction clutch according to claim 16, wherein said annular surface comprises the same degree of roughness as said working surfaces.
Claim 19
Dependent Claim
44 words
A fluid friction clutch according to claim 1, wherein said drive disk comprises two of said first working surfaces and said housing comprises two of said second working surfaces, one in spaced relationship with each of said first working surfaces to define two gaps.
Claim 20
Dependent Claim
29 words
A fluid friction clutch according to claim 1, wherein said selective introducing means comprises means for selectively introducing said fluid working medium in response to a change in temperature.
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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) | 1987-02-20 | 1987-08-22 | 1988-02-21 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1991-02-20 | 1991-08-22 | 1992-02-21 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1995-02-20 | 1995-08-22 | 1996-02-21 | $7700.00 | Window Closed / Lapsed |