Patent ID: 6945436

Claim:
A dispenser for dispensing extrudable material from a cartridge, said dispenser comprising: a housing including first and second recesses, the first recess configured to receive and position the cartridge so that a longitudinal axis of the cartridge is aligned with a longitudinal axis of the first and second recesses; a plunger movable along the longitudinal axis of the first and second recesses; a driver element, mounted in the second recess, that selectively engages and moves the plunger in a forward direction along the longitudinal axis of the first and second recesses, and selectively disengages from the plunger to allow the plunger to move in a rearward direction along the longitudinal axis of the first and second recesses; and a clutch element, confined within a cavity in the second recess, that selectively engages the plunger to restrain movement of the plunger in the rearward direction; such that, when the clutch element engages the plunger, movement of the plunger in the rearward direction is limited to a predetermined distance, said predetermined distance being controlled by a depth of said cavity and a thickness of the clutch element.