Heater and image heating apparatus including same

An image heating apparatus comprising:

• an endless belt;
• a heater that is in contact with an inner surface of the endless belt;
• and
• a nip portion forming member that forms a nip portion together with the heater through the endless belt,
• wherein a recording material bearing an image is heated while being pinched and conveyed by the nip portion,
• the heater comprising:
• an elongated substrate having a longer longitudinal dimension in a longitudinal direction thereof than a lateral dimension in a lateral direction thereof;
• and
• a first heat generation line provided on the substrate along the longitudinal direction;
• a second heat generation line provided on the substrate along the longitudinal direction at a position that is different in the lateral direction from that of the first heat generation line,
• wherein each of the first and second heat generation lines includes two heat generation blocks arranged in the longitudinal direction and electrically connected in series,
• wherein each of the heat generation blocks includes:
• a first conductive member provided along the longitudinal direction;
• a second conductive member provided along the longitudinal direction at a position that is different in the lateral direction from that of the first conductive member, and
• a plurality of heat generation resistive members electrically connected in parallel between the first conductive member and the second conductive member, each heat generation resistive member having a positive temperature coefficient of resistance.

A heater comprising:

• an elongated substrate having a longer longitudinal dimension in a longitudinal direction thereof than a lateral dimension in a lateral direction thereof;
• a first heat generation line provided on the substrate along the longitudinal direction;
• and
• a second heat generation line provided on the substrate along the longitudinal direction at a position that is different in the lateral direction from that of the first heat generation line,
• wherein each of the first and second heat generation lines includes two heat generation blocks arranged in the longitudinal direction and are electrically connected in series,
• wherein each of the heat generation blocks includes:
• a first conductive member provided along the longitudinal direction;
• a second conductive member provided along the longitudinal direction at a position that is different in the lateral direction from that of the first conductive member, and
• a plurality of heat generation resistive members electrically connected in parallel between the first conductive member and the second conductive member, each heat generation resistive member having a positive temperature coefficient of resistance.

An image heating apparatus comprising:

• an endless belt;
• a heater that is in contact with an inner surface of the endless belt;
• and
• a nip portion forming member that forms a nip portion together with the heater through the endless belt,
• wherein a recording material bearing an image is heated while being pinched and conveyed by the nip portion,
• the heater comprising:
• an elongated substrate having a longer longitudinal dimension in a longitudinal direction thereof than a lateral dimension in a lateral direction thereof;
• and
• a first heat generation line provided on the substrate along the longitudinal direction;
• and
• a second heat generation line provided on the substrate along the longitudinal direction at a position that is different in the lateral direction from that of the first heat generation line,
• wherein each of the first and second heat generation lines includes only one heat generation block,
• wherein the heat generation block includes:
• a first conductive member provided along the longitudinal direction;
• a second conductive member provided along the longitudinal direction at a position that is different in the lateral direction from that of the first conductive member, and
• a plurality of heat generation resistive members electrically connected in parallel between the first conductive member and the second conductive member, each heat generation resistive member having a positive temperature coefficient of resistance.

A heater comprising:

• an elongated substrate having a longer longitudinal dimension in a longitudinal direction thereof than a lateral dimension in a lateral direction thereof;
• a first heat generation line provided on the substrate along the longitudinal direction;
• and
• a second heat generation line provided on the substrate along the longitudinal direction at a position that is different in the lateral direction from that of the first heat generation line,
• wherein each of the first and second heat generation lines includes only one heat generation block,
• wherein the heat generation block includes:
• a first conductive member provided along the longitudinal direction;
• a second conductive member provided along the longitudinal direction at a position that is different in the lateral direction from that of the first conductive member, and
• a plurality of heat generation resistive members electrically connected in parallel between the first conductive member and the second conductive member, each heat generation resistive member having a positive temperature coefficient of resistance.