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US4694945A Expired / Lapsed US ⏱️ 0.0 years remaining

Electromagnetic clutch with an improved magnetic rotatable member

Assignee: TAKATOSHI KOITABASHI A CORP OF JAPAN
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Filing: 1984-10-16
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Granted: 1987-09-22
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Expires: 2004-10-16
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Abstract

Abstract An electromagnetic clutch includes a first rotatable member of magnetic material having an axial end surface and a hollow portion in which an annular electromagnetic device is disposed in a stationary position. A second rotatable member, such as a drive shaft, is provided within the first rotatable member. A hub is secured on the second rotatable member and a magnetic armature plate is supported on and around the hub. The magnetic armature plate, which faces the axial end surface of the first rotatable member at a predetermined axial air gap, is capable of limited axial movement and is attracted to the first rotatable member when the electromagnetic device is energized to frictionally engage the first rotatable member. In particular, in the electromagnetic clutch of this invention, the first rotatable member includes an outer cylindrical member, an inner cylindrical member and an axial end plate member which has an axial end surface connected therebetween, with the outer diameter of the axial end plate member exceeding the diameter of the outer cylindrical member and the inner diameter being smaller than the diameter of the inner cylindrical member.

Inventors

  • 👤 Takatoshi Koitabashi

Bibliographic Details

Application Number —
Jurisdiction US
Data Source google_patents
Last Synchronized 2026-11-06 20:02
CPC Classifications
B; B21; B21D; B21D53/00; B21D53/26; B21D53/261; B23; B23P; B23P15/00; B23P15/14; F; F16; F16D; F16D27/00; F16D27/10; F16D27/108; F16D27/112; F16D2027/008

Claims Analysis

Total Claims: 3
Claim 1
Independent Claim 198 words
An electromagnetic clutch including a first rotatable member of magnetic material rotatably supported on a bearing, an annular electromagnetic device disposed in a stationary position in a hollow portion of said first rotatable member, said annular electromagnetic device including an annular magnetic housing, an annular magnetic coil disposed therein, a second rotatable member, a hub secured on said second rotatable member, a magnetic armature plate supported on and around said hub at a predetermined radial gap, said magnetic armature plate being capable of limited axial movement and facing said first rotatable member at a predetermined axial air gap, said magnetic armature plate further being attracted to said first rotatable member when said annular magnetic coil is energized, the improvement comprising said first rotatable member comprising an outer cylindrical member, an inner cylindrical member and an axial end plate member which has an axial end surface connecting said outer and inner cylindrical members, wherein the outer diameter of said axial end plate member is larger than the diameter of any part of the outer cylindrical member and the inner diameter of said axial end plate member is smaller than the diameter of any part of the inner cylindrical member.
Claim 2
Dependent Claim 198 words
An electromagnetic clutch including a first rotatable member of magnetic material rotatably supported on a bearing, an annular electromagnetic device disposed in a stationary position in a hollow portion of said first rotatable member, said annular electromagnetic device including an annular magnetic housing, an annular magnetic coil disposed therein, a second rotatable member, a hub secured on said second rotatable member, a magnetic armature plate supported on and around said hub at a predetermined radial gap, said magnetic armature plate being capable of limited axial movement and facing said first rotatable member at a predetermined axial air gap, said magnetic armature plate further being attracted to said first rotatable member when said annular magnetic coil is energized, the improvement comprising said first rotatable member comprising an outer cylindrical member, an inner cylindrical member and an axial end plate member which has an axial end surface connecting said outer and inner cylindrical members, wherein the outer diameter of said axial end plate member is larger than the diameter of any part of the outer cylindrical member and the inner diameter of said axial end plate member is smaller than the diameter of any part of the inner cylindrical member.
Claim 3
Dependent Claim 44 words
The electromagnetic clutch of claim 1 wherein said first rotatable member is a single piece of pressed and drawn metal and an axial end portion of both of said cylindrical members is connected to said axial end plate member through a drawn flange portion.

References Cited (Backward Citations)

US4160498A Cited
US4305198A Cited
US4425520A Cited
US4432446A Cited
US4391356A Cited

USPTO Annuity & Maintenance Windows

Annuity Stage Window Opens Payment Deadline Surcharge Period Until Estimated Fee Status
3.5 Years (Year 4) 1990-09-21 1991-03-23 1991-09-22 $2000.00 Window Closed / Lapsed
7.5 Years (Year 8) 1994-09-21 1995-03-23 1995-09-22 $3760.00 Window Closed / Lapsed
11.5 Years (Year 12) 1998-09-21 1999-03-23 1999-09-22 $7700.00 Window Closed / Lapsed

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