Thumbwheel operated metering dispenser for adhesives

Abstract

A hand-held dispenser for delivering small, precisely controllable amounts of fluid or semi-fluid adhesives includes an elongated container having a hollow cylindrical barrel section terminated at the rear end thereof by a pair of diametrically opposed flange wings protruding radially outwards from opposite sides of the barrel, a reduced diameter front tubular outlet section extending forward from the barrel, and a flexible capillary delivery tube protruding outwards from the outlet section. A piston longitudinally slidably located within the bore of the barrel displaces adhesive within the bore forward of the piston by the turning of a lead screw which contacts the rear wall of the piston and which is threadably held within a support member attached to the rear portion of the barrel section. The lead screw is advanceable in precisely controlled small increments by a thumbwheel located rearward of the flange wings, the thumbwheel having a central coaxial perforation that longitudinally slidably receives the lead screw. Rotation of the thumbwheel relative to the lead screw is prevented by contact between a longitudinally disposed flat in the outer surface of the lead screw and a chordal wall that truncates the perforation through the thumbwheel. Thus constructed, the dispenser may be grasped in the fingers of one hand, and the thumb of the same hand used to rotate the thumbwheel and lead screw.