Patent ID: 8071213
Filing Date: 2011-12-06
Classification: F16F,F16J,Y10T

Abstract:
1. A resin coated piston manufacturing apparatus for a shock absorber in which a washer-shaped resin sheet is adhered to an outer periphery of a cylindrical piston raw material having a plurality of annular grooves in an outer periphery, comprising: a set mold coaxially provided with a piston set hole and a resin sheet set hole; a means for setting the piston raw material within the piston set hole of the set mold; a means for setting the resin sheet within the resin sheet set hole of the set mold; a means for pressing the piston raw material to the resin sheet including an axially reciprocating on a center axis of the set mold resin sheet presser foot provided at an upper portion of the set mold pressing an outer periphery of the resin sheet, the outer periphery of the resin sheet is pressed by the resin sheet presser foot at a time of locking the resin sheet by axial displacement of the piston raw material through a hole of the resin sheet until the resin sheet is locked to a resin sheet locking annular groove of the piston raw material; the outer periphery of the resin sheet is released after the locking, and the piston raw material to which the resin sheet is locked passes axially through an inner periphery of the resin sheet presser foot so as to be pressed into continuously arranged heating and cooling cylinder apparatuses in such a manner as to press the piston raw material to which the resin sheet is locked, the means for pressing the piston raw material is provided so as to freely reciprocate on a center axis of the set mold, is provided with an aligning guide capable of being fitted to an inner diameter of the piston raw material set to the piston set hole of the set mold, presses the piston raw material to the resin sheet so as to lock the resin sheet to the resin sheet locking annular groove of the piston raw material, and is capable of pressing the piston raw material to which the resin sheet is locked, to the heating and cooling cylinder apparatuses; wherein a heating cylinder of the heating and cooling cylinder apparatuses has an inlet end inner diameter (D) which is smaller than a dimension obtained by adding twice of a thickness of the resin sheet to an outer diameter of the piston raw material, and a heating cylinder inner diameter (E) which is continuously provided from the inlet end via an R chamfer portion and is smaller than the inlet end inner diameter (D); and a cooling cylinder of the heating and cooling cylinder apparatuses has an inner diameter which is larger than the heating cylinder inner diameter (E).