Improvements relating to Connecting of Tapered Spigots and Sockets

Abstract

Abstract 1,160,769. Tool shanks. PADLEY & VENABLES Ltd. 19 Oct., 1967 [28 Oct., 1966], No. 48360/66. Heading B4C. [Also in Divisions B3 and F2] A tapered spigot or socket comprises ductile material secured thereto and standing proud of the tapered surface, the exposed area of the ductile material not exceeding 50% of the area of the tapered surface and projecting beyond the tapered surface by 1À5%-4À5% of the largest dimension in cross-section at the mid-point of the taper so that upon the spigot or socket being assembled tightly with a complementary socket or spigot the ductile material is extruded between and wiped over the tapered surfaces. The tapered surface may be of circular, polygonal or elliptical cross-section and can be used in connecting a rotary drill bit or a percussive masonry bit to a driving member. The ductile material may be copper, zinc, aluminium or alloys thereof, or a plastics material such as nylon, and it may be secured by an adhesive such as varnish. The ductile material may be secured to the spigot or socket or both. In an example, Fig. 2, a length of copper wire 4 is bent around an annular groove 3. Material of part-circular cross-section may be used, giving the insert a frusto-conical outer surface. Longitudinal inserts may be used, Figs. 3, 4 (not shown), which may run in a spiral fashion, the receiving slots being of rectangular or rounded cross-section. A filigree sleeve (11), Fig. 6 (not shown), of knitted copper wire may be used, secured by shellac. Sockets.-Grooves 10 of rectangular or rounded cross-section are provided for rectangular strips or wire, respectively.

Inventors

• 👤 Michael John Henry Fowler

Bibliographic Details