Contact heat fixing device

A contact heat fixing device which comprises a driving heated roller having a heating mechanism disposed in the interior thereof and a surface coated with an offset preventing material, a press roller which is rotatable in intimate contact under pressure with said heated roller, said press roller and heated roller being rotatably mounted on a frame plate, a vessel for containing therein an offset preventing liquid and a feed mechanism for supplying the offset preventing liquid to the heated roller from the vessel, fixation of a toner image being accomplished by the passage of a support having the toner image thereon through the nip position of the heated roller and the press roller, wherein said feed mechanism includes an applicator for applying the offset preventing liquid to the surface of the heated roller and supply means for supplying the offset preventing liquid from the vessel to the applicator, said applicator being a roller, at least the surface portion of which is composed of a porous, heat-resistant and abrasion resistant material having a liquid absorbing property, said applicator roller being supported by a swingable arm so that it can be rotated only in the same direction as that of rotation of the heated roller and it can shift between a position (P1) where it has a pressing contact with said supply means and a position (P2) where it has a pressing contact with said heated roller, said swingable arm being fixed to a shaft which is rotatably mounted on the frame plate and connected through a linkage to an electromagnetic solenoid mechanism said solenoid mechanism being energized in connection with a mechanism to be actuated at every copying operation synchronously with feeding of the support, so that when said solenoid mechanism is energized, the applicator roller is moved to said position P2 to have a temporary contact with the surface of the heated roller and apply thereto the offset preventing liquid and when said solenoid mechanism is de-energized, said applicator roller being returned to the original position P1 by its own weight, and said applicator roller and said supply means being arranged in such a positional relationship that while the applicator roller shifts from the position P1 to the position P2, the applicator roller is rotated by frication with said supply means.