Center punch
OwnerHorace C. Skeltoninventor
Life of this patent
Estimating the term…
Abstract
A center punch particularly adapted for locating and marking the center position of a circular opening, as for making a center mark in a stud that has been broken off below the surface, to facilitate drilling and removing the stud. Movable jaws are each provided with an end portion of reduced thickness that extends into the opening adjacent the stud and a shoulder that abuts the exposed surface to retain the punch in a center position.
Claims3
A center punch comprising a tubular barrel having a plurality of parallel slots extending from one and thereof thereby to define a plurality of spaced circumferentially-positioned jaws, each of said jaws having a tapered external surface, a punch member having a point at one end thereof, means slidably retaining said punch member for longitudinal movement within said barrel, and clamping means releasably forcing said jaws inward comprising a collar in threaded engagement with said barrel and in compressive engagement with said tapered surfaces whereby adjustment of said collar causes radial movement of said jaws.
Dependencies are inferred from the claim text.