FIXING DEVICE AND IMAGE FORMING APPARATUS WITH SAME

摘要

A fixing device includes a housing, a magnetic flux generation source, a first rotary body, a second rotary body, a first core, a second core, a shaft portion, a magnetic shielding body and an air flow generator. The shaft portion has a hollow cylindrical shape, holds the second core on a peripheral surface and includes an internal space extending in an axial direction inside. The shaft portion serves as a rotary shaft in the rotation of the second core. The air flow generator generates an air flow flowing in the internal space of the shaft portion from one end side toward the other end side in the axial direction.

主权项

1. A fixing device, comprising:
a housing; a magnetic flux generation source fixed to the housing and configured to generate a magnetic flux; a first rotary body configured to be rotated in a predetermined direction and induction-heated by the magnetic flux; a second rotary body configured to be rotated in a predetermined direction, a nip portion through which a sheet carrying a toner image passes being formed between the first and second rotary bodies; a first core made of a magnetic material and configured to form a magnetic path, along which the magnetic flux passes, together with the first rotary body; a second core made of a magnetic material, arranged between the first core and the first rotary body when viewed from the magnetic path and rotatable in a predetermined direction; a shaft portion having a hollow cylindrical shape, configured to hold the second core on a peripheral surface, including an internal space extending along an axial direction inside and serving as a rotary shaft in the rotation of the second core; a magnetic shielding body made of a nonmagnetic material, arranged on a peripheral surface of the second core or the shaft portion and configured to shield or suppress the magnetic flux by being located in the magnetic path with rotation about the shaft portion; and an air flow generator configured to generate an air flow flowing in the internal space from one end side toward the other end side in the axial direction; the magnetic flux generation source being fixed to the housing to surround the second core extending in the axial direction when viewed in a direction perpendicular to the axial direction.