Browse Prior Art Database

Original Publication Date: 1981-Dec-31
Included in the Prior Art Database: 2004-Apr-02

Publishing Venue

Xerox Disclosure Journal


In document handlers employing belts for feeding documents onto the platen of a copy machine internal pressure and antiskew rollers may be provided to assure adequate drive force between the belt and platen for feeding documents onto and off of the platen, particularly in a document handler in which the document D is fed onto the platen in a first direction, then reversed and driven against a registration edge member 10 for exposure positioning, and then fed off from the platen. When the document D is reversed, minimal drive forces are desirable to prevent jamming of the document into the registration edge 10a with excessive force to damage the document. It is therefore known to release the pressure or antiskew rolls by means of solenoids or cams during the registration step. Here, by providing a non-rotating roll or bar 2 pressure loaded slidably against the interior of the document feed belt 4 by spring 5, at a downstream position along the belt 4, adequate pressure is provided to feed documents D onto and off of the copy machine platen glass 6. Roll 2 is mounted for pivotal movement about pivot 7. When a document D is being fed onto or off of the platen, the roll 2 is maintained in the illustrated position by integral lever arm 8 engaging stationary stop 9. However, when the belt 4 is reversed to register the document against registration edge 10, the entire roll assembly 2, 5, 8 pivots about pivot 7, thereby removing the force of roll 2 from the belt 4 to prevent overdriving the document into the registration edge by allowing slippage between the belt 4 and document D, which also assists deskewing the document D into alignment with edge 10a. The force of rotatable pressure roller 11 may be retained against belt 4 near the registration edge 10a at all times if desired. Preferably there can be an additional removable antiskew pressure member 2 spaced along the belt path from the first one illustrated here and similarly operated.