Caulk dispensing device with multi-position thrust selection dial

Claim 1

A caulking gun, comprising: a frame for carrying a caulking composition; a plunger shaft having a piston at one end for urging said caulking composition out of said frame; a plunger driving assembly for driving said plunger shaft, said plunger driving assembly further comprising, a housing having a downwardly extending handle, a trigger extending upwardly within the housing, said trigger being pivoted to said housing above said plunger shaft for hand contracting against said handle, a first gripping member enclosed within said housing, said first gripping member encircling the plunger shaft and protruding upwardly beyond the plunger shaft within said housing, a first compression spring oppositely biasing said first gripping member toward said trigger; a selection dial pivotally mounted for axial rotation about an upward tip of said trigger for varying a thrust output of said caulking gun, said selection dial being selectively rotatable into a first position for engagement with the upward protrusion of said first gripping member when said trigger is contracted, and into a second non-engaging position when said trigger is contracted; whereby said first gripping member may be driven by said selection dial when in the first position to increase the incremental displacement of said plunger shaft when said trigger is contracted.