Patent ID: 7494462

Claim:
A method for manufacturing an endoscopic manual control knob to be used on an endoscope for manipulation of an insertion instrument, said manual control knob being of the sort having a knob body of synthetic resin molding largely constituted by a ring-like top plate and a peripheral wall portion of a predetermined width formed integrally along marginal edges of said top plate, an aperture perforated centrally through said top plate, a plural number of lever portions projected radially outward from angularly spaced positions around outer periphery of said top plate, each one of said lever portions being provided with a finger grip surface at an outer distal end, and said aperture of said top plate being fitted on a rotating shaft projected from a manipulating head assembly of said endoscopic insertion instrument, said method comprising the steps of: preparing an insert member having a plural number of implant blocks at outer distal ends of radial connecting arms extending radially outward from a center core; setting said insert member within a cavity of a mold in a molding stage of said knob body, in such positions that the respective implant blocks of said insert member are located in lever portions to be formed; introducing a synthetic resin material into said mold to form said knob body on said insert member, having said implant blocks completely embedded in said lever portions of said knob body by a cover wall portion formed integrally with said knob body to cover lower side of said implant blocks remote from said top plate of said knob body; and cutting off at least radial connecting arm portions falling within boundaries of said aperture in said top plate.