GB540990A - Improvements in and relating to pistons - Google Patents

Abstract

540,990. Making pistons. AUTOMOTIVE ENGINEERING CO., Ltd., WHITE, P., DENNIS, E., and NICOLLE, A. V. July 12, 1940, No. 11641. [Classes 83 (i) and 83 (ii)] [Also in Group XXVI] . Casting composite articles.-In an aluminium or other light metal or alloy piston, a wear-resisting bearing surface for a piston ring is provided by a number of inserts 3 which are separated circumferentially by the metal of the piston and are made of iron, steel, or other material harder than that of the piston body 2. The inserts may comprise similar flat strips or stampings disposed edgewise around the piston and used separately or in small groups, or a fewer number of cast segments. To improve the interlocking of the inserts with the piston body, the former are provided with transverse openings or with lugs 4. To secure their proper location, the inserts may be threaded on a thin flat steel strip by means of openings, lugs, or projections on the outer edges of the inserts, this strip being subsequently removed and the lugs or projections removed during machining of the piston. Alternatively, the inserts may be formed integrally on their outer edge with a narrow lug 6 which locates the assembly in the mould and prevents relative radial displacement, and with a wider lug 5 which is welded to one or a pair of wires 7. The inserts rest in a groove in the mould to prevent axial displacement.