Hand held electric caulking gun

A hand held electric caulking gun including in combination, a receptacle for receiving therein a caulk containing cartridge having a caulk dispensing nozzle, a piston movable when driven through said cartridge to force the caulking therein from said nozzle, a reciprocating cam surface, driving means for said reciprocating cam surface including an electric motor, a speed reducing drive train connecting said motor with said reciprocating cam surface whereby operation of said motor effects reciprocating movement of said cam surface, piston gripping means movable by reciprocating movement of said cam surface to engage in gripping relation the surface of said piston to move said piston through said cartridge to force the caulking therein from said nozzle and clutch means interposed between said motor and piston and operative to drivably disengage the motor from the piston upon a predetermined movement retarding pressure being applied to the piston during operation of said motor.

A hand held electric caulking gun including in combination, a receptacle for receiving therein a caulk containing cartridge having a caulk dispensing nozzle thereon, a piston movable when driven through said cartridge to force the caulking therein from said nozzle, driving means for said piston including a driving plate disposed about said piston and movable when driven to grip the surface of said piston to move said piston through said cartridge, driving means for said plate including a cam surface movable when driven to drive said plate, an electric motor, a speed reducing drive train connecting said motor with said cam surface and operable, upon operation of said motor, to drive said cam surface, and clutch means disposed between said piston and motor and operative upon a predetermined movement retarding force being applied to said piston during operation of said motor to drivably disengage the motor from said piston.

A hand held electric caulking gun including in combination, a receptacle for receiving therein a caulk containing cartridge having a caulk dispensing nozzle thereon, a piston movable when driven through said cartridge to force the caulking therein from said nozzle, driving means for said piston including plate means movable when driven to grip the surface of said piston to drive said piston through said cartridge, a reciprocating surface movable to drive said plate means, an electric motor, a speed reducing drive train connecting said motor with said reciprocating surface and operable when driven by said motor to effect movement of said reciprocating surface, holding means movable to hold said piston in its plate driven position and clutch means disposed in said speed reducing drive train between said motor and piston and operative to drivably disengage the motor from the piston upon a predetermined movement arresting pressure being applied to the caulk driving end of said piston during operation of said motor.