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US4934930A Expired / Lapsed US ⏱️ 0.0 years remaining

Heat roller fixing device and image fixing method

Assignee: Ricoh Co Ltd
•
Filing: 1988-12-23
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Granted: 1990-06-19
•
Expires: 2008-12-23
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Abstract

Abstract A heating roller having a surface layer of Teflon® and a pressing roller having a surface layer of an elastomeric material are held rotatably against each other for fixing a full-color toner image to a toner carrier therebetween. The ratio (1/V) between the nip width 1 of the heating and pressing rollers and the peripheral speed V of the rollers is selected to be at least 0.06, and the pressure of contact per unit area between the heating and pressing rollers at their nip region is selected to be at least 7 kg/cm 2 , for increasing a temperature range corresponding to the rubber range of toners used. The toners which have a small molecular weight and a small molecular weight distribution are prevented from being offset before the toners are fixed. Teflon® with desirable features can therefore be used as the surface layer of the heating roller.

Inventors

  • 👤 Setsuo Soga

Bibliographic Details

Application Number —
Jurisdiction US
Data Source google_patents
Last Synchronized 2026-11-04 03:32
CPC Classifications
G; G03; G03G; G03G13/00; G03G13/20; G03G15/00; G03G15/20

Claims Analysis

Total Claims: 6
Claim 1
Independent Claim 121 words
A fixing device for fixing a toner image by passing a toner carrier with toner images of plural colors carried on a surface thereof, between a heating roller and a pressure roller which are pressed against each other, wherein said heating roller has a surface layer made of silicone rubber having a thickness ob 0.4 mm at most, and said pressing roller has a surface layer made of an elastic material, wherein each of said rollers has a nip width, L, and a peripheral speed, v, with the ratio L/v being at least 0.07 sec., and the pressure of contact between said rollers per nip area is at least 6 kg/cm 2 , wherein a wide toner fixing range is obtained.
Claim 2
Dependent Claim 121 words
A fixing device for fixing a toner image by passing a toner carrier with toner images of plural colors carried on a surface thereof, between a heating roller and a pressure roller which are pressed against each other, wherein said heating roller has a surface layer made of silicone rubber having a thickness ob 0.4 mm at most, and said pressing roller has a surface layer made of an elastic material, wherein each of said rollers has a nip width, L, and a peripheral speed, v, with the ratio L/v being at least 0.07 sec., and the pressure of contact between said rollers per nip area is at least 6 kg/cm 2 , wherein a wide toner fixing range is obtained.
Claim 3
Dependent Claim 22 words
The fixing device of claim 1, wherein said pressing roller has a surface layer made of silicone rubber as said elastic material.
Claim 4
Dependent Claim 20 words
The fixing device of claim 1, comprising a means for detecting the temperature of the surface of said heating roller.
Claim 5
Dependent Claim 36 words
The fixing device of claim 1, comprising a means for detecting the temperature of the surface of said heating roller and a temperature controller means for controlling the temperature of the surface of said heating roller.
Claim 6
Dependent Claim 20 words
The fixing device of claim 1, comprising a means for pressing said rollers against each other and a drive means.

References Cited (Backward Citations)

US4038026A Cited
US4101267A Cited
US4119831A Cited
US4487158A Cited
US4653897A Cited
US4639405A Cited
US4745431A Cited
US4727394A Cited
US4814819A Cited

USPTO Annuity & Maintenance Windows

Annuity Stage Window Opens Payment Deadline Surcharge Period Until Estimated Fee Status
3.5 Years (Year 4) 1993-06-18 1993-12-18 1994-06-19 $2000.00 Window Closed / Lapsed
7.5 Years (Year 8) 1997-06-18 1997-12-18 1998-06-19 $3760.00 Window Closed / Lapsed
11.5 Years (Year 12) 2001-06-18 2001-12-18 2002-06-19 $7700.00 Window Closed / Lapsed

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