Solenoid-controlled mechanisms, particularly sheet registration mechanisms.

摘要

A solenoid-controlled sheet registration mechanism for a copier/printer includes registration fingers (13) for registering the lead edge of a sheet before it is fed to the transfer station (4) of the copier/printer, to receive a developed image from the photoreceptor (1). The mechanism also includes a pair of nip rolls (11, 12) for forwarding the sheet to the transfer station, after registration. Energization of the solenoid (16) moves the registration fingers into the registration position and disengages the nip rolls (11, 12). Conversely, release of the solenoid allows the registration fingers to return to a non-registration position and the nip rolls to return to paper-feeding engagement, both of those return movements taking place under a resilient bias. To soften the impact between the nip rolls as they re-engage, and so reduce any resulting noise, the release of the solenoid is controlled by applying a pulsed drive signal (35) to the solenoid during the release period after the energizing signal (28) has ceased.