Connecting rod with bearing-less large end

Abstract

A connecting rod of an internal combustion engine, that includes a large bore, and an interior bore surface. The current art uses soft metal bearing surfaces to reduce wear, and friction between the connecting rod inner diameter and the crankshaft journal surface. The soft metal bearing surface is a separate component of the engine. In this invention the large bore end interior diameter is coated with a hard material to reduce, or eliminate wear. The hard material is a metal or metal alloy applied to the inner diameter by a thermal spray method. A relatively soft polymer material can also be applied to the interior diameter surface of the con-rod bore. The relatively softer polymer acts as a first and sometimes a consumable layer, and applied over the thermal sprayed hard layer. The polymer layer is often used in conjunction with the sprayed metal layer. The polymer coating may be worn off the inner diameter surface; this delay in surface to surface contact to the sprayed metal layer has beneficial effects on the sprayed metal layer. The delay of surface to surface contact will usually result in a longer service life of the sprayed metal coating.