Patent ID: 8170435
Filing Date: 2012-05-01
Classification: G03G

Abstract:
1. A belt driving mechanism, comprising: a first belt supporter and a second belt supporter; an endless belt rotatably wound around the first belt supporter and the second belt supporter; a driving source connected to one of the first belt supporter and the second belt supporter to rotate the endless belt; a pressure member that presses against the first belt supporter via the endless belt, forming a nip therebetween; a deviation detector to detect a deviation of the endless belt in a thrust direction of the endless belt; a cam mechanism to adjust pressure between the pressure member and the first belt supporter between both end portions thereof in the thrust direction of the endless belt, the cam mechanism including: a second pressure change member disposed coaxially with the first pressure change member, to press a second end portion opposite the first end portion of one first belt supporter and the pressure member and to rotate in synchronization with the first pressure change member, a controller to change a rotational position of the first pressure change member by rotating the cam shaft according to a detection result generated by the deviation detector, wherein the second pressure change member has a shape different from that of the first pressure change member, the first pressure change member and the second pressure change member have a reference point where lift amounts of the first pressure change member and the second pressure change member are substantially identical, and the lift amounts of the first pressure change member and the second pressure change member change differently according to a rotational angle of the first pressure change member and the second pressure change member from the reference point.