Patent attributes
A screw-operated dispenser providing for prevention of breakage of an engaged screw when a user rotates a turn member in the wrong direction, i.e., repels rather than propels an elevator. A tubular body holds a supply of product, which is dispensed by action of the elevator along a threaded shaft upon turning a base to either propel or repel the elevator along the shaft which is threadably engaged with the elevator. Certain lowermost revolutions of the thread on the shaft are chamfered at the bottom edge thereof so that when the elevator is in a lowermost position on the screw shaft and a user mistakenly rotates the turn member in a repel direction, the thread of the elevator will not engage, i.e., will override, the thread of the screw shaft thereby eliminating stress and/or pressure between the threads which may result in breakage of the screw shaft and render the dispenser inoperable.
