Patent ID: 6017481
Filing Date: 2000-01-25
Classification: B29C,B29L,B60R,B62D

Abstract:
A method of making a unitary composite steering wheel and air bag cover assembly for an inflatable air bag system, the method comprising the steps of:injecting a first molten plastic at a first injection station having a shape defining a first part including a rim portion having circular inner and outer contact surfaces;hardening the resulting first part;providing a one-piece skeletal frame structure having an air bag aperture extending completely therethrough and surrounded by a circular rim portion;moving the hardened first part and the skeletal frame structure into a second injection station having a shape defining the entire assembly;injecting a second molten plastic at the second injection station at a temperature and pressure sufficient to melt the circular inner and outer contact surfaces of the rim portion of the first part;hardening the resulting assembly to bond the first and second plastics by diffusion at the circular inner and outer contact surfaces with the circular rim portion of the skeletal frame structure therebetween; andremoving the completed assembly from the second injection station wherein one of the molten plastics is a plastic which forms a one-piece body including the rim portion and an air bag cover portion with a predetermined tear seam design formed therein at its respective injection station and the other of the molten plastics is a plastic which forms a one-piece rear rim portion having circular inner and outer contact surfaces bonded to the inner and outer contact surfaces of the rim portion.