Patent ID: 7702270

Claim:
A fixing device comprising: a fixing part for conveying a sheet of paper that is held between a pressure body and a fixing body that are rotatably supported about substantially parallel shafts while simultaneously fixing supported unfixed toner; and a separation mechanism for separating the sheet of paper, which is carried away from the fixing part, from the fixing body or pressure body; wherein the separation mechanism has a separation member provided with a separation pawl for separating the sheet of paper and a shaft member, a support part for pivotably supporting the separation member via the shaft member so that the separation pawl can be brought near to and separated from the fixing body or pressure body, and a first urging mechanism for pivotably urging the separation member in a direction in which the separation pawl approaches the fixing body or pressure body; the shaft member is provided so as to be movable between an initial position on the support part for the separation, and a retracted position that is set apart from the fixing part with respect to the initial position; the urging force created by the first urging mechanism operates such that a pressing force is generated in a direction in which the shaft member is displaced from the retracted position toward the initial position; wherein a control part is provided for controlling, at said initial position, the pivoting range of the separation pawl toward the fixing body or pressure body by applying a contact pressure; a second urging mechanism is provided that is separate from the first urging mechanism and that is used for directly pressing and urging the shaft member toward the initial position; and the magnitude of the resultant force of the pressing force created by the urging force created by the first urging mechanism and the pressing force created by the urging force of the second urging mechanism is set such that, in a normal state in which a paper jam has not occurred, the shaft member can be prevented from moving from the initial position to the retracted position regardless of the magnitude of the adhesive force of the sheet of paper on the fixing body or the pressure body, and such that the shaft member is moved from the initial position to the retracted position by contact pressure exerted by a jammed sheet of paper on the separation pawl.