Media guide mechanism, fixing device and image forming apparatus incorporating same

摘要

A mechanism for guiding a recording medium into a nip formed between a first rotary member subjected to heating, and a second rotary member pressed against the first rotary member includes a guide member and a biasing member. The guide member is disposed upstream from the nip to guide the recording medium therealong. The biasing member is connected to the guide member to mechanically bias the guide member. The guide member is subjected to a constant biasing force from the biasing member and to a pressure force from the recording medium. The pressure force is opposite the biasing force and variable with a stiffness of the recording medium being guided. The guide member is movable to different operational positions depending on the biasing and pressure forces acting thereon.

主权项

1. A mechanism for guiding a recording medium into a nip formed between a first rotary member subjected to heating, and a second rotary member pressed against the first rotary member, the mechanism comprising:
a guide member disposed upstream from the nip to guide the recording medium therealong; and a biasing member connected to the guide member to mechanically bias the guide member, the guide member being subjected to a constant biasing force from the biasing member and to a pressure force from the recording medium, the pressure force being opposite the biasing force and variable with a stiffness of the recording medium being guided, the guide member being movable to different operational positions depending on the biasing and pressure forces acting thereon, wherein the guide member comprises: a shaft defining a rotational axis around which the guide member is rotatable; a pair of upstream and downstream guide plates arranged in series in a direction in which the recording medium is conveyed to together define a smooth, continuous guide surface along which the recording medium is guided, and the shaft is affixed to the downstream guide plate but not to the upstream guide plate.