Roll fuser apparatus and release agent metering system therefor

Claim 1

In a contact fuser apparatus having a heated roll structure cooperating with a backup roll structure to form a nip through which copy substrates carrying toner images pass with said toner images contacting the heated fuser roll, wherein a release agent contained in a sump is applied to the surface of the heated roll structure to minimize offset of toner thereto and facilitate separation of the substrate from the heated fuser roll, the improvement comprising a rotatably supported donor roll contacting said heated roll structure and a smooth metal-surfaced rotatably supported metering roll supported for contact with said donor roll and said release agent in said sump, and a metering blade contacting said metering roll for metering said release agent to a predetermined thickness thereon, said donor roll comprising a deformable surface capable of having a pair of nips formed therein through pressure contact with said heated roll structure and said metering roll, and further comprising means coupled to said heated roll structure for effecting rotation of said structure and, in turn, rotation of said rolls by said heated roll structure.