Door-actuated feed roll separator mechanism for an imaging device

An imaging device comprising:

• a frame having a pair of opposed panels spaced apart and having a media path therebetween;
• a door pivotally mounted along a bottom edge thereof to the frame, the door having a raised closed position and a lowered open position, the door substantially covering the media path between the pair of opposed panels when in the closed position;
• a feed roll pair mounted across the media path and between the pair of opposed panels, the feed roll pair having a drive roll and a backup roll forming a feed nip therebetween, the drive roll having a shaft having a radius R1, the backup roll having a shaft having a radius R2 wherein a distance between respective surfaces of the shafts of the backup roll and the drive roll is a predetermined distance D1, the drive roll being rotatably mounted to the pair of opposed panels, and, the backup roll being translateably mounted to the pair of opposed panels and spring-biased into contact with the drive roll;
• and,
• a separator mechanism for separating the backup roll from the drive roll, the separator mechanism including:
• a spring-biased first actuator arm pivotally mounted on an inner surface of the door and extending therefrom toward the feed roll pair, the first actuator arm having a free end with a cylindrical pin depending transversely therefrom;
• and,
• a first cam follower rotatably mounted on the shaft of the backup roll, the first cam follower comprising a compliant plate having:
• a top, a bottom, a first side surface and a second side surface;
• a mounting slot having a circular end having a radius equal to or greater than R2 and positioned approximately in the center of the plate and sized to rotatably receive the shaft of the backup roll, the mounting slot having an open end extending through the second side surface and the bottom with a width of the open end being less than 2R2;
• an engagement slot having a first wall and a second wall angled to form a generally V-shaped opening with an open end positioned in the top of the plate, the first and second walls having a first and a second catch point, respectively;
• the first side surface having an upper concave portion and a lower planar portion forming a first camming surface, the first camming surface positioned at a distance D2 from the surface of the shaft of the backup roll that is greater than distance D1;
• and,
• the second side surface and a portion of the top adjacent to the second side surface forming an inverted L-shaped second camming surface,
• wherein, when the door is in the closed position, the pin is biased into the engagement slot and the first cam follower is in a disengaged position with respect to the shaft of the drive roll and the feed nip is closed with a spacing between respective centers of the shafts of the backup roll and drive roll being substantially equal to R1+R2+D1, and, as the door is opened, the pin engages with the second catch point rotating the first cam follower in a first direction so that the first camming surface contacts the shaft of the drive roll translating the backup roll away from the drive roll to open the feed nip and placing the first cam follower in an engaged position with the shaft of the drive roll with the spacing between respective centers of the shafts of the backup roll and drive roll being substantially equal to R1+R2+D2, and, as the door continues to open, the pin disengages from the second catch point and exits the engagement slot disengaging the first actuator arm from the first cam follower.

An imaging device comprising:

• a frame having a pair of opposed panels spaced apart and having a media path therebetween;
• a door pivotally mounted along a bottom edge thereof to the frame, the door having a raised closed position and a lowered open position, the door substantially covering the media path between the pair of opposed panels when in the closed position;
• a feed roll pair mounted across the media path and between the pair of opposed panels, the feed roll pair having a drive roll and a backup roll forming a feed nip therebetween, the drive roll having a shaft having a radius R1, the backup roll having a shaft having a radius R2 wherein a distance between respective surfaces of the shafts of the backup roll and the drive roll is a predetermined distance D1, the drive roll being rotatably mounted to the pair of opposed panels, and, the backup roll having a pair of bushings mounted on respective ends of the shaft of the backup roll with the pair of bushings being translateably mounted to respective ones of the pair of opposed panels, and a pair of springs wrapped around a respective one of the pair of bushings and having ends fastened to a respective one of the pair of opposed panels, the pair of springs applying a force to the backup roll to bias the backup roll into contact with the drive roll;
• and,
• a separator mechanism for separating the backup roll from the drive roll, the separator mechanism including:
• a pair of upper stops and a pair of lower stops mounted adjacent a front and a back edge of the door on an inner surface thereof;
• a first and a second actuator arm respectively pivotally mounted adjacent the front and the back edge of the door on the inner surface thereof between the respective upper and lower stops of the pairs of upper and lower stops, the first and second actuator arms extending toward respective ends of the backup roll, each actuator arm having a first end and a second end with the second end having a cylindrical pin depending transversely therefrom;
• a pair of biasing springs positioned between the respective first ends of the first and second actuator arms and a respective one of the pair of lower stops, the pair of biasing springs biasing the respective first ends of the first and second actuator arms against the respective one of the pair of upper stops moving the respective second ends of the first and second actuator arms in a downward direction;
• and,
• a pair of cam followers rotatably mounted on respective ends the shaft of the backup roll, each cam follower comprising a compliant plate having:
• a top, a bottom, a first side surface and a second side surface;
• a downwardly angled mounting slot having a closed circular end having a radius equal to or greater than R2 and positioned approximately in the center of the plate and sized to rotatably receive the shaft of the backup roll, the mounting slot having an open end extending through the second side surface and the bottom with a width W of the mounting slot being less than 2R2;
• an upwardly oriented engagement slot having a first wall and a second wall acutely angled to form a generally V-shaped opening with an open end positioned in the top of the plate, the first and second walls having a first and a second catch point, respectively;
• the first side surface having an upper concave portion having a radius R3 with respect to a center of the shaft of the drive roll that is greater than R1 and a lower planar portion forming a first camming surface, the first camming surface positioned at a distance D2 from the surface of the shaft of the backup roll that is greater than the distance D1;
• and,
• the second side surface and a portion of the top adjacent to the second side surface forming an inverted L-shaped second camming surface,
• wherein, when the door is in the closed position, the pins are biased into their respective engagement slots and the pair of cam followers are in a disengaged position with respect to the shaft of the drive roll, the upper concave portion of the first side surface is adjacent to but spaced apart from the shaft of the drive roll and the feed nip is closed with a spacing between the respective centers of the shafts of the backup roll and drive roll being substantially equal to R1+R2+D1, and, as the door is opened, the pins engage with their respective second catch points rotating the pair of cam followers in a first direction so that the respective first camming surfaces contact the respective ends of the shaft of the drive roll translating the backup roll away from the drive roll to open the feed nip and placing the pair of cam followers in respective engaged positions with the shaft of the drive roll where the spacing between respective centers of the shafts of the backup roll and the drive roll substantially equals R1+R2+D2, and, as the door continues to open the pins disengage from their respective second catch points and exit their respective engagement slots disengaging each of the first and second actuator arms from their respective one of the pair of cam followers.