Patent ID: 7223231

Claim:
In a casing for manipulating a head assembly of an endoscope, said casing being formed of a synthetic resin material and largely constituted by a main cover section and a grip cover section, said main cover section being adapted to support thereon an operating member of an angulation control mechanism, and said grip cover section being projected forward from said main cover section to provide a grip portion between said main cover section and an insertion tube of said endoscope: a rigid support plate provided mostly within said main cover section and partly in said grip cover section to support said angulation control mechanism; a passage forming structure for passing through internal components to or from said insertion tube of said endoscope comprising a plural number of tubular members successively connected one after another within said grip cover section, a base end tubular member of said passage forming structure being connected to said rigid support plate and a fore end tubular member thereof being connected to said insertion tube; a first anti-twist lock portion for blocking rotational movements of said grip cover section relative to said main cover section; and a second anti-twist lock portion formed between a joint portion of said passage forming structure and said grip cover section of said casing; wherein said first anti-twist lock portion being formed by placing opposite edge portions of said support plate in a pair of axial grooves provided on inner surfaces of said main and grip cover sections of said casing.