Patent ID: 8813924

Claim:
A manufacturing method for an upper support wherein: the upper support comprises (a) a cup piece forming an inner piece, (b) an outer piece disposed around the inner piece in a position offset in a radial direction, and (c) a rubber elastic body integrally vulcanize adhered to the inner piece and the outer piece in a state where the inner piece and the outer piece are elastically connected to the rubber elastic body; and the upper support is anchored to a piston rod for a shock absorber on an inner piece side, and the upper support is anchored to a vehicle body on an outer piece side, the upper support elastically connecting the piston rod and the vehicle body and acting to prevent vibration; the manufacturing method for the upper support comprising: integrally vulcanize adhering the cup piece directly to the rubber elastic body, the cup piece including: a tubular portion; a base portion having a piston rod insertion hole in a center of a bottom end of the tubular portion; and a flanged portion jutting in a radially outward direction at a top end of the tubular portion on a side opposite to the base portion, providing the cup piece such that the shape of the tubular portion prior to integral vulcanized adhesion with the rubber elastic body is a shape comprising: an upper portion continuous with the flanged portion as a large diameter portion; a lower portion on the base portion as a small diameter portion; and a portion between the large diameter portion and the small diameter portion as a stepped portion, and following the integral vulcanized adhesion with the rubber elastic body, diameter widening the small diameter portion by press-fitting a diameter widening jig into the small diameter portion to impart pre-compression to a portion of the rubber elastic body corresponding to the small diameter portion while diameter widening is not performed on the large diameter portion, which retains its dimensions and shape.