Ricoh Company, Ltd.

Richo Company, Ltd.

Yuichiro Higashi

Ryoichi Namiki

Yasuo Asahina

Setsuo Soga

Toshiyuki Kikuchi

Ichiro Fukushima

Tadaaki Kanno

A fixing apparatus installed in a copying machine or the like and having a fixing roller, a pressure roller and sheet separator pawls engagable with the fixing roller. A first mechanism of the fixing apparatus is operable to locate free or separating ends of the sheet separator pawls at a small spacing from the periphery of the fixing roller. A pivotable second mechanism is operable to move the sheet separator pawls over a substantial distance away from the fixing and pressure rollers to define a large space in front thereof, so that the peripheries of the rollers become accessible for services.

Fixing apparatus for copying machine or the like

An image fixing device for an electrophotographic copying apparatus and the like including a fixing roller and a pressing roller in pressing contact with each other. The fixing roller includes a metallic core, a resilient material layer and an offset preventing layer superposed one over another in the indicated order and having a heating member disposed therein for heating the metallic core. A copy sheet formed thereon with a toner image is passed between the two rolls so that the toner image will be fixed to the copy sheet by melt adhesion by being pressed between them while being heated. The offset preventing layer has a higher heat intake than the toner image so as to be highly responsive to heat. The offset preventing layer is formed of a material containing a synthetic resinous material, such as silicone rubber, silicone resin, etc., which is highly resistant to heat and which has a high parting property, added with over 1% by weight of metal powder of high thermal conductivity. To prevent the temperature at the surface of the fixing roll from dropping from a level necessary for obtaining satisfactory fixing of images when a plurality of toner images are consecutively fixed, the resilient material layer preferably has a thermal conductivity of over 1.times.10.sup.-3 cal/cm..degree.C. sec.

Image fixing device

Improved heat roller fixing apparatus comprising an inner cylinder having a heater therein, an outer cylinder, and a vacuum chamber which is formed between the inner cylinder and the outer cylinder and which contains a liquid heat transfer medium at low pressure is described. In particular, improvements obviating excessive heating of the inner cylinder are made by placing the heat transfer medium in the chamber so as to be in contact with the lower portion of the inner cylinder at least when said outer cylinder is stationary, or by mounting on the inner cylinder a member which serves to stir or pour the heating medium on the inner cylinder and also to transfer heat indirectly from the inner cylinder to the outer cylinder through the heating medium so that speedy evaporation of the heating medium and safe and stable fixing of images are accomplished.

Heat roller fixing apparatus

Growing community of inventors

Kawasaki, Japan

Yuichiro Higashi