Method of manufacturing tubular film
AssigneeCanon Kabushiki Kaisha
InventorsKazutaka Takeuchi, Shoichi Shimura
Life of this patent
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Abstract
A tubular film having a high film thickness uniformity and suitable for a fixing film of an image forming apparatus is provided. To achieve such a film, a thermoplastic sheet film is so wound that the leading and trailing end portions of the film partially overlap each other to form overlapping portions, and the wound film is heated between a core member and a tubular molding member.
Claims21
A method of manufacturing a tubular film used in an image forming apparatus, comprising the steps of:
- winding a thermoplastic sheet film on a columnar member;
- overlapping leading and trailing end portions of said film;
- fitting a tubular molding member on said wound film;
- and
- connecting the overlapped portions of said film by heating at least said film, thereby forming said sheet into a tubular film,
- wherein a thermal expansion coefficient of said columnar member is larger than a thermal expansion coefficient of said tubular molding member.
A method of manufacturing a tubular film, comprising the steps of:
- winding a thermoplastic sheet film on a columnar member, overlapping leading and trailing end portions of said film on each other, and fitting a tubular molding member on said wound film;
- connecting the overlapping portions of said film by heating at least said film, thereby forming said sheet film into a tubular film,
- wherein a difference between an inner diameter of said tubular molding member and an outer diameter of said columnar member is twice as large as a desired thickness of a tubular film at a temperature necessary for heating-welding of said sheet film, and
- wherein said film and said columnar member fitted in said tubular molding member are cooled to a predetermined temperature after being heated;
- and
- peeling said film from said tubular molding member after molding.
A method of manufacturing a tubular film used in an image forming apparatus, comprising the steps of:
- winding a thermoplastic sheet film 5 to 300 .mu.m in thickness on a columnar member so that leading and trailing end portions of said film partially overlap each other;
- covering said wound film with a tubular molding member whose inner diameter is larger by not less than 15 .mu.m than outer diameter of said columnar member;
- and
- connecting the overlapping portions of said film by holding at least said film within a temperature range from a melt temperature to a decomposition thereof temperature for a predetermined time.
A method of manufacturing tubular film, comprising the steps of:
- winding a first thermoplastic sheet film a plurality of number of times on a columnar member so that leading and trailing end portions partially overlap each other;
- winding a second thermoplastic sheet film a plurality of number of times on said wound first sheet film so that leading and trailing end portions partially overlap each other;
- covering said first and second films with a tubular molding member;
- connecting the overlapping portions by heating said first and second films to a temperature, at which the overlapping portions are connected, for a predetermined time, thereby forming a multilayered tubular films;
- cooling said columnar member, said films, and said tubular molding member after the heating step;
- and
- peeling said film from said tubular molding member after molding.
A method of manufacturing a tubular film, comprising the steps of:
- winding a thermoplastic sheet film on a columnar member so that leading and trailing ends of said film partially overlap each other;
- fitting a thermoplastic tube on said sheet film;
- fitting a tubular molding member on said thermoplastic tube;
- and
- connecting the overlapping portions by heating at least said sheet film within a temperature range from a melt temperature to a decomposition temperature thereof.
A method of manufacturing a tubular film, comprising the steps of:
- fitting a non-thermoplastic tube on a columnar member;
- winding a thermoplastic sheet film on said tube so that leading and trailing end portions of said film partially overlap each other;
- fitting a tubular molding member on said sheet film;
- and
- connecting the overlapping portions by heating at least said sheet film within a temperature range from a melt temperature to a decomposition temperature thereof.
A method of manufacturing a tubular film, comprising the steps of:
- fitting a non-thermoplastic first tube on a columnar member;
- fitting a thermoplastic second tube on said first tube;
- fitting a tubular molding member on said second tube;
- connecting overlapping portions of said first tube and said second tube by heating at least said second tube within a temperature range from a melt temperature to a decomposition temperature thereof;
- and
- cooling said columnar member, said film, and said tubular molding member after the heating step.
Dependencies are inferred from the claim text.