Patent ID: 9393814
Filing Date: 2016-07-19
CPC Classification: B41J

Claim Text:
1. A printing unit, comprising: a main body frame; a thermal head mounted on the main body frame; a platen roller arranged so as to be opposed to the thermal head, which is configured to convey a recording sheet by rotating about an axis extending along a first direction under a state in which the recording sheet is nipped between the platen roller and the thermal head; roller insertion grooves formed in the main body frame, into which the platen roller is inserted in a state of being removable from the roller insertion grooves along a second direction orthogonal to the first direction; a lock arm supported so as to be pivotable about a pivot shaft extending along the first direction, which is configured to hold the platen roller inserted into the roller insertion grooves; a moving mechanism configured to move the pivot shaft and including: biasing members configured to bias the lock arm; and gripping portions provided to the lock arm, which are configured to extend from a region opposite to the thermal head across the platen roller toward the thermal head under a holding state in which the gripping portions hold the platen roller, in which a distal end portion of each of the gripping portions is formed so as to be located close to the thermal head side with respect to an imaginary plane including a center axis of the platen roller and an axis of the pivot shaft under the holding state, in which the moving mechanism is configured to move the pivot shaft between a locking position where a pivot of the lock arm is restricted under the holding state and a pivoting position where the lock arm is freely pivotable between the holding state and a releasing state in which the platen roller is removable from the roller insertion grooves, and in which the biasing members are configured to: