ROLLER TRANSFER APPARATUS

摘要

A transfer roller apparatus for use for example in an electrostatographic copier including a dielectric member adapted to carry electrostatically developed marking particle images on successive image receiving areas. The transfer roller apparatus, employing a locating and tacking mechanism capable of accurately locating a receiver member on the periphery of the transfer roller (12) is driven to synchronize transfer roller rotation with dielectric member movement for accurate transfer of marking particle images to a receiver member on such roller peripheral surface. The drive for the transfer roller (12) includes a gear train with the first gear coupled to a motive source and the last gear (94) to the roller (12). The transfer roller (12) is articulatable to a first position in operative relation with the dielectric member, a second position in operative relation with a roller surface cleaner, or a third rest position intermediate the first and second positions. Further, an electrical bias is applied to the roller (12) to establish a transfer field between the roller and the dielectric member to effect transfer of marking particle images from the dielectric member to a receiver member accurately located on the peripheral surface of the roller. A discontinuity in the transfer field is created in the area of the roller surface over which locating and tacking of a receiver member are effected. Additionally, the locating and tacking mechanism includes a flexible member (32) having a receiver member locating feature. The flexible member (32) is attached to the transfer roller (12) such that the feature is normally in a first position extending above the peripheral surface of the roller for locating the receiver member on the peripheral surface, and is urged to a second position at least coincident with the peripheral surface to prevent damage to the dielectric member as the roller rotates to bring the flexible member in opposed relation to the dielectric member.