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US4714819A Expired / Lapsed US ⏱️ 0.0 years remaining

Directly heating fixing apparatus having current collecting bearings

Assignee: Proterial Ltd
•
Filing: 1986-07-14
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Granted: 1987-12-22
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Expires: 2006-07-14
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Abstract

Abstract A directly heating type fixing apparatus for use in an image forming device such as an electronic copying machine, has a heating roll which includes an heat generating electric resistance layer and a toner releasing layer both formed on the surface of a cylindrical body thereof, and a pressure roll which is arranged to contact the heating roll under pressure. Current collecting bearings made of an electrically conductive material are provided on both sides of the heating roll, respectively. These current collecting bearings and the heat generating electric resistance layer of the heating roll are electrically connected with each other.

Inventors

  • 👤 Keitaro Yamashita

Bibliographic Details

Application Number —
Jurisdiction US
Data Source google_patents
Last Synchronized 2026-11-03 16:12
CPC Classifications
G; G03; G03G; G03G15/00; G03G15/20; G03G15/2003; G03G15/2014; G03G15/2053

Claims Analysis

Total Claims: 10
Claim 1
Independent Claim 114 words
A directly heating-type fixing apparatus having a heating roll which includes a heat generating electric resistance layer and a covering layer of a heat resistant toner releasing material, both layers being formed on a surface of a cylindrical body, and a pressure roll which is arranged to contact said heating roll under pressure, the apparatus further comprising a pair of current collecting bearings each made of an electrically conductive material provided at ends of said heating roll, respectively, said current collecting bearings supporting said heating roll against contact by said pressure roll, and said current collecting bearings and the heat generating electric resistance layer of said heating roll being electrically connected with each other.
Claim 2
Dependent Claim 114 words
A directly heating-type fixing apparatus having a heating roll which includes a heat generating electric resistance layer and a covering layer of a heat resistant toner releasing material, both layers being formed on a surface of a cylindrical body, and a pressure roll which is arranged to contact said heating roll under pressure, the apparatus further comprising a pair of current collecting bearings each made of an electrically conductive material provided at ends of said heating roll, respectively, said current collecting bearings supporting said heating roll against contact by said pressure roll, and said current collecting bearings and the heat generating electric resistance layer of said heating roll being electrically connected with each other.
Claim 3
Dependent Claim 33 words
The apparatus as claimed in claim 1, wherein said cylindrical body is made of a metal and an insulating layer is formed between said cylindrical body and said heat generating electric resistance layer.
Claim 4
Dependent Claim 54 words
The apparatus as claimed in claim 2, wherein said heat generating electric resistance layer extends outwardly of both ends of said toner releasing layer in the axial direction, electrode rings are provided on extensions of said heat generating electric resistance layer, and said electrode rings are slidably in contact with said current collecting bearings.
Claim 5
Dependent Claim 17 words
The apparatus as claimed in claim 1, wherein said current collecting bearings are made of a graphite.
Claim 6
Dependent Claim 40 words
The apparatus as claimed in claim 1, wherein said cylindrical heating roll is hollow and a temperature fuse operatively connected to interrupt electric power to said heating roll is provided inside of said hollow roll for the prevention of overheating.
Claim 7
Dependent Claim 49 words
The apparatus as claimed in claim 1, wherein said cylindrical heating roll is hollow, and the apparatus further includes a temperature sensor operatively connected to control the electric power to said heating roll, wherein said temperature sensor is provided in contact with an inner surface of the cylindrical body.
Claim 8
Dependent Claim 17 words
The apparatus as claimed in claim 2, wherein said current collecting bearings are made of a graphite.
Claim 9
Dependent Claim 17 words
The apparatus as claimed in claim 3, wherein said current collecting bearings are made of a graphite.
Claim 10
Dependent Claim 50 words
The apparatus as claimed in claim 1, wherein said cylindrical heating roll is hollow, and the apparatus further includes a temperature sensor operatively connected to control the electric current to said heating roll, wherein said temperature sensor is provided to lie closely adjacent an inner surface of the cylindrical body.

References Cited (Backward Citations)

US1973234A Cited
US2957562A Cited
US3310655A Cited
US3417219A Cited
US3636306A Cited
US4105896A Cited
US4063066A Cited
US4116422A Cited
US4395109A Cited
US4362502A Cited
US4618240A Cited
US4560860A Cited

USPTO Annuity & Maintenance Windows

Annuity Stage Window Opens Payment Deadline Surcharge Period Until Estimated Fee Status
3.5 Years (Year 4) 1990-12-21 1991-06-22 1991-12-22 $2000.00 Window Closed / Lapsed
7.5 Years (Year 8) 1994-12-21 1995-06-22 1995-12-22 $3760.00 Window Closed / Lapsed
11.5 Years (Year 12) 1998-12-21 1999-06-22 1999-12-22 $7700.00 Window Closed / Lapsed

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