Patent ID: 8087550

Claim:
A dispensing device for dispensing viscous material wherein said dispensing device is convertible from being arranged to dispense viscous material in bulk to dispensing viscous material packaged in a cartridge, said cartridge including a conical tip and an internal axially-moveable disc, said device comprising: a. an elongated chamber for housing the viscous material, said elongated chamber having an opening at a distal end comprising a passage though which the viscous material can be dispensed; b. a piston rod in sliding relation with a trigger assembly, said piston rod having a forward end; c. an ejector removably retained on the forward end of said piston rod, wherein said ejector is capable of engaging the axially-moveable disc within said cartridge containing the viscous material to be dispensed; and, d. a piston cup having at least one outer peripheral edge sealingly received in said elongated chamber and slidable therein, wherein when said dispensing device is configured for dispensing viscous material in bulk, said ejector and said piston cup are situated adjacent one another on the forward end of said piston rod, and wherein when the dispensing device is configured for dispensing viscous material packaged in a cartridge, said piston cup is slid back and away from said ejector while being retained on said piston rod to reduce the possibility of the piston cup from being lost.