US4320284A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Heated fuser roll
Assignee: Pitney Bowes Inc
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Filing: 1980-10-22
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Granted: 1982-03-16
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Expires: 2000-10-22
Abstract
Abstract A heated fuser roll for use in a fuser apparatus for fixing toner images to a support surface is disclosed. The fuser roll includes a circular sleeve member having at least one heating unit positioned within the sleeve member. Each heating unit includes (i) a plurality of axially disposed thermally conductive members each formed of a chordal section having a curved surface positioned in contiguous relation to the inside curved surface of the sleeve member and a substantially flat surface, (ii) a plurality of wafer shaped heating elements formed of a semiconducting ceramic material having a positive temperature coefficient of resistivity and exhibiting a Curie temperature transition point at which the resistance of the material increases with increasing temperature, the elements being positioned along the flat surface of each of the conductive members, and (iii) resilient means positioned in contiguous relation to the heating elements for exerting a substantially continuous pressure on the heating elements to keep them in contact with the conductive members. Each of the heating units is separated from each other by an insulating member.
Inventors
- 👤 Hugh S. Dannatt
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-08 23:45
CPC Classifications
G; G03; G03G; G03G15/00; G03G15/20; G03G15/2003; G03G15/2014; G03G15/2053; H; H05; H05B; H05B3/00; H05B3/0095
Claims Analysis
Total Claims: 15
Claim 1
Independent Claim
238 words
A heated fuser roll for use in a fuser apparatus for fixing toner images to a support surface, said fuser roll comprising: a. a circular sleeve member; b. a plurality of heating units positioned within said sleeve member, each unit including (i) a plurality of axially disposed thermally conductive members each formed of a chordal section having a curved surface positioned in contiguous relation to the inside curved surface of said sleeve member and a substantially flat surface, the chordal sections being set apart within said sleeve at about 120° one to another, (ii) a plurality of wafer shaped heating elements formed of a semiconducting ceramic material having a positive temperature coefficient of resistivity and exhibiting a Curie temperature transition point at which the resistance of said material increases with increasing temperature, said elements being positioned in contiguous relation to one another along said flat surface of each of said conductive members, and (iii) resilient means in the form of an open coil spring extending axially within said sleeve member positioned in contiguous relation to said heating elements for exerting a substantially continuous pressure on said heating elements to keep said elements in contact with said conductive members and to provide a plurality of independent multiple electrical contacts with said elements; and c. each heating unit being separated from the adjacent heating unit by an insulating member, said spring of each unit extending to abut the insulating member.
Claim 2
Dependent Claim
238 words
A heated fuser roll for use in a fuser apparatus for fixing toner images to a support surface, said fuser roll comprising: a. a circular sleeve member; b. a plurality of heating units positioned within said sleeve member, each unit including (i) a plurality of axially disposed thermally conductive members each formed of a chordal section having a curved surface positioned in contiguous relation to the inside curved surface of said sleeve member and a substantially flat surface, the chordal sections being set apart within said sleeve at about 120° one to another, (ii) a plurality of wafer shaped heating elements formed of a semiconducting ceramic material having a positive temperature coefficient of resistivity and exhibiting a Curie temperature transition point at which the resistance of said material increases with increasing temperature, said elements being positioned in contiguous relation to one another along said flat surface of each of said conductive members, and (iii) resilient means in the form of an open coil spring extending axially within said sleeve member positioned in contiguous relation to said heating elements for exerting a substantially continuous pressure on said heating elements to keep said elements in contact with said conductive members and to provide a plurality of independent multiple electrical contacts with said elements; and c. each heating unit being separated from the adjacent heating unit by an insulating member, said spring of each unit extending to abut the insulating member.
Claim 3
Dependent Claim
36 words
A fuser roll according to claim 1 wherein said resilient means has a self-adjusting resiliency whereby said resilient means remains in contiguous contact with said heating elements during the heating and cooling cycles of said fuser.
Claim 4
Dependent Claim
17 words
A fuser roll according to claim 1 wherein said spring is formed of an electrically conductive material.
Claim 5
Dependent Claim
23 words
A fuser roll according to claim 3 wherein said spring is formed of steel wire coated with a layer of copper or silver.
Claim 6
Dependent Claim
29 words
A fuser roll according to claim 1 wherein each of said heating elements have two opposed substantially flat and parallel surfaces, each of said surfaces being plated with metal.
Claim 7
Dependent Claim
15 words
A fuser roll according to claim 5 wherein said metal plating is silver or aluminum.
Claim 8
Dependent Claim
21 words
A fuser roll according to claim 1 further comprising means for supplying an electrical current to each of said heating units.
Claim 9
Dependent Claim
24 words
A fuser roll according to claim 1 wherein said ceramic material exhibits a Curie temperature ranging from about 150° C. to about 220° C.
Claim 10
Dependent Claim
21 words
A fuser roll according to claim 8 wherein said ceramic material comprises barium titanate, strontium titanate, and/or lead titanate and lanthanum.
Claim 11
Dependent Claim
17 words
A fuser roll according to claim 1 wherein said sleeve is made of aluminum, copper or brass.
Claim 12
Dependent Claim
18 words
A fuser roll according to claim 1 further comprising an outer layer of silicone rubber covering said sleeve.
Claim 13
Dependent Claim
17 words
A fuser roll according to claim 1 further comprising an outer layer of polytetra-fluoroethylene covering said sleeve.
Claim 14
Dependent Claim
232 words
A heated fuser roll for use in a fuser apparatus for fixing toner images to a support surface, said fuser roll comprising: a. a circular sleeve member; b. a plurality of heating units positioned within said sleeve member, each unit including (i) a plurality of axially disposed thermally conductive members each formed of a chordal section extending from the inside surface of said sleeve, said chordal sections each having a flat surface, the chordal sections being set apart within said sleeve at about 120° one to another, (ii) a plurality of wafer shaped heating elements formed of a semiconducting ceramic material having a positive temperature coefficient of resistivity and exhibiting a Curie temperature transition point at which the resistance of said material increases with increasing temperature, said elements being positioned in contiguous relation to one another along said flat surface of each of said conductive members, and (iii) resilient means in the form of an open coil spring extending axially within said sleeve member positioned in contiguous relation to said heating elements for exerting a substantially continuous pressure on said heating elements to keep said elements in contact with said conductive members and to provide a plurality of independent multiple electrical contacts with said elements; and c. each heating unit being separated from the adjacent heating unit by an insulating member, said spring of each unit extending to abut the insulating member.
Claim 15
Dependent Claim
232 words
A heated fuser roll for use in a fuser apparatus for fixing toner images to a support surface, said fuser roll comprising: a. a circular sleeve member; b. a plurality of heating units positioned within said sleeve member, each unit including (i) a plurality of axially disposed thermally conductive members each formed of a chordal section extending from the inside surface of said sleeve, said chordal sections each having a flat surface, the chordal sections being set apart within said sleeve at about 120° one to another, (ii) a plurality of wafer shaped heating elements formed of a semiconducting ceramic material having a positive temperature coefficient of resistivity and exhibiting a Curie temperature transition point at which the resistance of said material increases with increasing temperature, said elements being positioned in contiguous relation to one another along said flat surface of each of said conductive members, and (iii) resilient means in the form of an open coil spring extending axially within said sleeve member positioned in contiguous relation to said heating elements for exerting a substantially continuous pressure on said heating elements to keep said elements in contact with said conductive members and to provide a plurality of independent multiple electrical contacts with said elements; and c. each heating unit being separated from the adjacent heating unit by an insulating member, said spring of each unit extending to abut the insulating member.
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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) | 1985-03-15 | 1985-09-14 | 1986-03-16 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1989-03-15 | 1989-09-14 | 1990-03-16 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1993-03-15 | 1993-09-14 | 1994-03-16 | $7700.00 | Window Closed / Lapsed |