Matsushita Electric Industrial Co., Ltd.

Masaomi Inoue

Keisuke Fujimoto

Masaru Imai

Masaaki Nakano

Syuuiti Watanabe

Noboru Katakabe

Masahiro Inata

Yoshito Saji

Masakazu Mizusaki

A heating roller () includes a heat generating layer () that generates heat by electromagnetic induction, a heat insulating layer (), and a supporting layer (), which are provided inwardly in this order. The supporting layer () is formed of a material having a specific resistance of 1&#xd7;10&#x3a9;m or higher. Therefore, even when the heat generating layer () has a thickness smaller than a skin depth, i.e. a thickness defined by a flow of an induction current, so that magnetic flux penetrates the heat generating layer () and even reaches the supporting layer (), heat generation of the supporting layer () under an eddy current can be suppressed. Thus, the heat generating layer () can be decreased in thermal capacity, and heat generation of the supporting layer () is suppressed, so that only the heat generating layer () can be heated efficiently. As a result, a warm-up time can be reduced. Further, breakage by heat of, for example, bearings supporting the heating roller () can be prevented.

Heating roller, image heating apparatus, and image forming apparatus

A heating roller () includes a heat generating layer () that generates heat by electromagnetic induction, a heat insulating layer (), and a supporting layer (), which are provided inwardly in this order. The heat generating layer () is composed of at least two layers that are a first heat generating layer of a magnetic material and a second heat generating layer of a non-magnetic material. The first heat generating layer has a specific resistance higher than a specific resistance of the second heat generating layer and a thickness larger than a thickness of the second heat generating layer. This allows the second heat generating layer to function effectively as a heat generating part that generates heat by electromagnetic induction. Thus, compared with the case where the heat generating layer () is formed only of a single layer of a magnetic material, heat generation efficiency is increased, thereby allowing warm-up time to be reduced. Further, the heat generating layer () is heated intensively, so that heat generation of the supporting layer () is reduced, thereby allowing the prevention of breakage of, for example, bearings supporting the heating roller ().

Heating roller, heating belt, image heating device, and image forming device

An optical disk device of the present invention includes an optical pickup which performs at least recording or reproduction of signals on or from an optical disk; a guiding section which supports and guides the optical pickup along the radial direction of the optical disk; an upper cover which protects the guiding section; a lower cover which protects the guiding section; and a base which supports the guiding sections therein. A height between the upper cover and the lower cover adjacent to an outer periphery of the optical disk is greater than a height between the upper cover and the lower cover adjacent to an inner periphery of the optical disk.

Optical disk device having increased height at an outer periphery of the optical disk

Growing community of inventors

Onojo, Japan

Masaomi Inoue