Patent ID: 6170348
Filing Date: 2001-01-09
Classification: B41J,B65H,Y10T

Abstract:
A transmission for transmitting power from a printing device drive to drive a media pick roller to move media from a printing device media supply tray comprising:a) a support chassis;b) a transmission power input gear mounted on said chassis;c) a sun gear mounted on said chassis for rotation about a first axis and driveably connected to said power input gear;d) a media pick roller drive gear mounted for rotation on said chassis;e) a planetary gear mounting arm mounted on said chassis for pivotal movement about said first axis;f) a planet gear mounted for rotation on said mounting arm, said planet gear being driveably connectable to said pick roller drive gear;g) a cam track mounted on said chassis centered on said first axis and arcuately extending from a first location to a second location proximate said media pick roller drive gear, said cam track having a transmission engagement cam surface which inclines from said first location to said second location, said cam track also having a transmission reset cam surface spaced from said engagement cam surface, said reset cam surface extending from said second location to said first location;h) a swing arm mounted on said chassis for movement with said mounting arm about said first axis, said swing arm having a cam follower thereon engageable with said cam track surfaces and said cam follower when engaged with said inclined engagement cam surface being resiliently biased away from said mounting arm; whereby,(1) during a transmission engagement phase, said power input gear may rotate said sun gear, said mounting arm and said swing arm together in a first direction to arcuately move said follower in engagement with said engagement cam surface from said first location to said second location to move said planet gear into driving relationship with said pick roller drive gear,(2) during a drive phase, said swing arm and said mounting arm remain stationary while power may be transmitted by rotation of said input gear in a second direction to rotate said sun gear to rotate said planet gear to rotate said drive gear,(3) during a transmission disengagement phase, said power input gear again may rotate said sun gear, said mounting arm and said swing arm together in said first direction to arcuately move said follower past an end of said cam track to disengage said follower from said engagement cam surface and to disengage said planet gear from driving relationship with said pick roller drive gear, and(4) during a reset phase, said power input gear may rotate said sun gear, said mounting arm and said swing arm in a second direction with said follower engaged with said reset cam surface to return said mounting arm and said swing arm to said first position.