Roller-shaped heater and fusing unit using a roller-shaped heater

A fusing unit comprising:

• a roller-shaped heater comprising:
• a cylindrically formed roller member;
• and a heat generator composed of a heat-resisting insulation material and resistance heating elements formed on the heat-resisting insulation material wherein the heat generator is composed of a multiple number of separated portions extending in the axial direction of a cylinder of the roller member, and each portion includes at least one of the resistance heating elements formed on a section of the heat-resisting insulation material, the section being non-integral to sections of the heat-resisting insulation material included in adjacent portions;
• and
• a pressing member is disposed abutting against the roller-shaped heater,
• characterized in that fusing is performed by conveying a recording medium having an unfused toner image supported thereon through a nip between the roller-shaped heater and the pressing member.

A fusing unit comprising:

• a roller-shaped heater comprising:
• a cylindrically formed roller member;
• and a heat generator composed of a heat-resisting insulation material and resistance heating elements formed on the heat-resisting insulation material wherein the heat generator is provided with a multiple number of resistance heating elements extending in parallel with each other in the axial direction of a cylinder of the roller member, wherein the heat-resisting insulation material comprises a plurality of discrete sections each having at least one of the resistance heating elements formed thereon;
• and
• a pressing member disposed abutting against the roller-shaped heater,
• characterized in that fusing is performed by conveying a recording medium having an unfused toner image supported thereon through a nip between the roller-shaped heater and the pressing member.

A fusing unit comprising:

• a roller-shaped heater comprising:
• a cylindrically formed roller member;
• and a heat generator composed of a heat-resisting insulation material and resistance heating elements formed on the heat-resisting insulation material wherein the heat generator is composed of a multiple number of separated portions extending in the axial direction of a cylinder of the roller member and each portion has the resistance heating element;
• and
• a pressing member is disposed abutting against the roller-shaped heater,
• characterized in that fusing is performed by conveying a recording medium having an unfused toner image supported thereon through a nip between the roller-shaped heater and the pressing member,
• wherein electric power is selectively supplied to one of the resistance heating elements in the heat generator which corresponds to the nip area formed between the roller-shaped heater and the pressing member.

A fusing unit comprising:

• a roller-shaped heater comprising:
• a cylindrically formed roller member;
• and a heat generator composed of a heat-resisting insulation material and resistance heating elements formed on the heat-resisting insulation material wherein the heat generator is provided with a multiple number of resistance heating elements extending in parallel with each other in the axial direction of a cylinder of the roller member;
• and
• a pressing member disposed abutting against the roller-shaped heater,
• characterized in that fusing is performed by conveying a recording medium having an unfused toner image supported thereon through a nip between the roller-shaped heater and the pressing member, and
• wherein electric power is selectively supplied to one of the resistance heating elements in the heat generator which corresponds to the nip area formed between the roller-shaped heater and the pressing member.

A fusing unit comprising:

• a roller-shaped heater comprising:
• a cylindrically formed roller member;
• and a heat generator composed of a heat-resisting insulation material and resistance heating elements formed on the heat-resisting insulation material wherein the heat generator is composed of a multiple number of separated portions extending in the axial direction of a cylinder of the roller member and each portion has the resistance heating element;
• and
• a pressing member is disposed abutting against the roller-shaped heater,
• characterized in that fusing is performed by conveying a recording medium having an unfused toner image supported thereon through a nip between the roller-shaped heater and the pressing member,
• wherein the roller-shaped heater has a power receiving portion at one end of the heat generator through which electric current is supplied to the resistance heating elements formed in the heat generator and the pressing member is disposed abutting against the roller-shaped heater, so that fusing is performed by conveying a recording medium having an unfused toner image supported thereon through the nip between the roller-shaped heater and the pressing member, and
• wherein electric power is selectively supplied to one of the resistance heating elements in the heat generator which corresponds to the nip area formed between the roller-shaped heater and the pressing member.

A fusing unit comprising:

• a roller-shaped heater comprising:
• a cylindrically formed roller member;
• and a heat generator composed of a heat-resisting insulation material and resistance heating elements formed on the heat-resisting insulation material wherein the heat generator is provided with a multiple number of resistance heating elements extending in parallel with each other in the axial direction of a cylinder of the roller member;
• and
• a pressing member disposed abutting against the roller-shaped heater,
• characterized in that fusing is performed by conveying a recording medium having an unfused toner image supported thereon through a nip between the roller-shaped heater and the pressing member,
• wherein the roller-shaped heater has a power receiving portion at one end of the heat generator through which electric current is supplied to the resistance heating elements formed in the heat generator and the pressing member is disposed abutting against the roller-shaped heater, so that fusing is performed by conveying a recording medium having an unfused toner image supported thereon through the nip between the roller-shaped heater and the pressing member, and
• wherein electric power is selectively supplied to one of the resistance heating elements in the heat generator which corresponds to the nip area formed between the roller-shaped heater and the pressing member.

A fusing unit comprising:

• a roller-shaped heater comprising:
• a cylindrically formed roller member;
• and a heat generator composed of a heat-resisting insulation material and resistance heating elements formed on the heat-resisting insulation material wherein the heat generator is composed of a multiple number of separated portions extending in the axial direction of a cylinder of the roller member and each portion has the resistance heating element;
• and
• a pressing member is disposed abutting against the roller-shaped heater,
• characterized in that fusing is performed by conveying a recording medium having an unfused toner image supported thereon through a nip between the roller-shaped heater and the pressing member, and
• wherein electric power can be supplied to all the resistance heating elements in the heat generator so that the entire roller-shaped heater is heated and also electric power can be selectively supplied to one of the resistance heating elements in the heat generator which corresponds to the nip area formed between the roller-shaped heater and the pressing member.

A fusing unit comprising:

• a roller-shaped heater comprising:
• a cylindrically formed roller member;
• and a heat generator composed of a heat-resisting insulation material and resistance heating elements formed on the heat-resisting insulation material wherein the heat generator is provided with a multiple number of resistance heating elements extending in parallel with each other in the axial direction of a cylinder of the roller member;
• and
• a pressing member disposed abutting against the roller-shaped heater,
• characterized in that fusing is performed by conveying a recording medium having an unfused toner image supported thereon through a nip between the roller-shaped heater and the pressing member, and
• wherein electric power can be supplied to all the resistance heating elements in the heat generator so that the entire roller-shaped heater is heated and also electric power can be selectively supplied to one of the resistance heating elements in the heat generator which corresponds to the nip area formed between the roller-shaped heater and the pressing member.

A fusing unit comprising:

• a roller-shaped heater comprising:
• a cylindrically formed roller member;
• and a heat generator composed of a heat-resisting insulation material and resistance heating elements formed on the heat-resisting insulation material wherein the heat generator is composed of a multiple number of separated portions extending in the axial direction of a cylinder of the roller member and each portion has the resistance heating element;
• and
• a pressing member is disposed abutting against the roller-shaped heater,
• characterized in that fusing is performed by conveying a recording medium having an unfused toner image supported thereon through a nip between the roller-shaped heater and the pressing member,
• wherein the roller-shaped heater has a power receiving portion at one end of the heat generator through which electric current is supplied to the resistance heating elements formed in the heat generator and the pressing member is disposed abutting against the roller-shaped heater, so that fusing is performed by conveying a recording medium having an unfused toner image supported thereon through the nip between the roller-shaped heater and the pressing member, and
• wherein electric power can be supplied to all the resistance heating elements in the heat generator so that the entire roller-shaped heater is heated and also electric power can be selectively supplied to one of the resistance heating elements in the heat generator which corresponds to the nip area formed between the roller-shaped heater and the pressing member.

A fusing unit comprising:

• a roller-shaped heater comprising:
• a cylindrically formed roller member;
• and a heat generator composed of a heat-resisting insulation material and resistance heating elements formed on the heat-resisting insulation material wherein the heat generator is provided with a multiple number of resistance heating elements extending in parallel with each other in the axial direction of a cylinder of the roller member;
• and
• pressing member disposed abutting against the roller-shaped heater,
• characterized in that fusing is performed by conveying a recording medium having an unfused toner image supported thereon through a nip between the roller-shaped heater and the pressing member,
• wherein the roller-shaped heater has a power receiving portion at one end of the heat generator through which electric current is supplied to the resistance heating elements formed in the heat generator and the pressing member is disposed abutting against the roller-shaped heater, so that fusing is performed by conveying a recording medium having an unfused toner image supported thereon through the nip between the roller-shaped heater and the pressing member, and
• wherein electric power can be supplied to all the resistance heating elements in the heat generator so that the entire roller-shaped heater is heated and also electric power can be selectively supplied to one of the resistance heating elements in the heat generator which corresponds to the nip area formed between the roller-shaped heater and the pressing member.