US3854562A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Electromagnetic clutch
Assignee: BARCLAYSAMERICAN/BUSINESS CREDIT INC 530 NORTH WATER STMILWAUKEE WS A CORP OF CT
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Filing: 1973-08-15
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Granted: 1974-12-17
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Expires: 1993-08-15
Abstract
Abstract A simplified compact electromagnetic clutch comprising a stationary field, a rotor and an armature, the field is a hollow cylindrical housing of magnetic material with inner and outer peripheral walls defining an annular recess to receive a plastic bobbin having a toroidal coil and a tubular offset extension through which the coil leads extend and which cooperates with a receiving aperture in the housing to extend therethrough as a lead wire strain relief and an anchor to prevent rotation of the field. The rotor comprises a hollow cylinder of magnetic material with a radial flange at one end, an outer collar, and a thinwalled, injection-molded, connecting portion of acetal homopolymer securing the cylinder and collar together and providing both radially and axially extending bearing surfaces for contact with the field housing which is retained on the rotor assembly by a snap ring. The rotor is mounted on a supporting shaft by press fitting the same onto a knurled portion of the shaft, and the armature is a disc of magnetic material having a square bore axially slidable on a square hub of a drive gear rotatably mounted on the supporting shaft.
Inventors
- 👤 R Wilczewski
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-03 11:45
CPC Classifications
F; F16; F16D; F16D27/00; F16D27/10; F16D27/108; F16D27/112; F16D2027/008
Claims Analysis
Total Claims: 12
Claim 1
Independent Claim
157 words
An electromagnetic clutch mounted on a supporting shaft, comprising a unitary rotor having a hollow cylindrical inner portion of magnetic material secured to said shaft with a radially extending flange at one end, an outer collar portion of magnetic material, and a thin-walled connecting member of nonmagnetic bearing material injection molded to secure said inner and outer portions together in radially spaced relation and define a cylindrical bearing, a stationary field comprising a coil housing of magnetic material having a bore supported by said bearing and inner and outer axial flanges joined by an outer end wall to define an annular recess, a bobbin of non-magnetic plastic mounted in said recess, a toroidal coil wound on said bobbin, and an armature disc movable axially into contact with said rotor in response to energization of said coil; and a drive member rotatably mounted on said shaft and having relative axially slidable and non-rotatable engagement with said armature disc.
Claim 2
Dependent Claim
157 words
An electromagnetic clutch mounted on a supporting shaft, comprising a unitary rotor having a hollow cylindrical inner portion of magnetic material secured to said shaft with a radially extending flange at one end, an outer collar portion of magnetic material, and a thin-walled connecting member of nonmagnetic bearing material injection molded to secure said inner and outer portions together in radially spaced relation and define a cylindrical bearing, a stationary field comprising a coil housing of magnetic material having a bore supported by said bearing and inner and outer axial flanges joined by an outer end wall to define an annular recess, a bobbin of non-magnetic plastic mounted in said recess, a toroidal coil wound on said bobbin, and an armature disc movable axially into contact with said rotor in response to energization of said coil; and a drive member rotatably mounted on said shaft and having relative axially slidable and non-rotatable engagement with said armature disc.
Claim 3
Dependent Claim
39 words
An electromagnetic clutch according to claim 1, wherein said cylindrical inner portion of said rotor is provided with a peripheral groove, and a snap ring mounted in said groove to prevent axial separation of said field from said rotor.
Claim 4
Dependent Claim
50 words
An electromagnetic clutch according to claim 2, wherein said shaft is provided with a knurled portion and said rotor is press-fitted onto said knurled portion of said shaft to comprise, with said snap ring, the sole means for connecting said field and said rotor as a unit on said shaft.
Claim 5
Dependent Claim
16 words
An electromagnetic clutch according to claim 1, wherein said injection-molded bearing material is an acetal homopolymer.
Claim 6
Dependent Claim
28 words
An electromagnetic clutch according to claim 1, wherein said injection-molded connecting member also defines a radial bearing for engaging the axially inner end of said field coil housing.
Claim 7
Dependent Claim
47 words
An electromagnetic clutch according to claim 1, wherein said outer end wall of said coil housing is provided with an aperture and said bobbin is provided with a tubular offset extension through said aperture accommodating leads from said coil and functioning as a lead wire strain relief.
Claim 8
Dependent Claim
25 words
An electromagnetic clutch according to claim 6, wherein said offset extension on said bobbin comprises means for preventing rotation of said field with said rotor.
Claim 9
Dependent Claim
55 words
An electromagnetic clutch according to claim 1, wherein the outer surface of said inner axial flange of said coil housing is provided with a peripheral groove, and said bobbin is provided with an inner annular rib which frictionally engages in said groove to maintain engagement of said bobbin in said annular recess of said housing.
Claim 10
Dependent Claim
41 words
An electromagnetic clutch according to claim 1, wherein said outer collar portion of said rotor is provided with an axially outer part aligned with said radially extending flange and an axially inner part overlying the inner end of said field housing.
Claim 11
Dependent Claim
47 words
An electromagnetic clutch according to claim 9, wherein the major portion of said field housing and said rotor have the same outer diameter, and said inner end of said field housing is peripherally reduced to provide clearance for said axially inner part of said rotor collar portion.
Claim 12
Dependent Claim
31 words
An electromagnetic clutch according to claim 1, wherein the bore of said field coil housing is axially stepped to reduce the surface area thereof engaging said cylindrical bearing of said rotor.
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) | 1977-12-16 | 1978-06-17 | 1978-12-17 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1981-12-16 | 1982-06-17 | 1982-12-17 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1985-12-16 | 1986-06-17 | 1986-12-17 | $7700.00 | Window Closed / Lapsed |