Joint construction for angle section of endoscopic insertion rod

摘要

A joint construction for connecting a flexibly bendable angle section of an endoscopic insertion rod with an anteriorly and/or posteriorly located section of the insertion rod, including a line-wrapping layer formed on a fore end portion of a resilient outer skin layer of the angle section at a joint with the adjoining section, and a rigid cover ring fitted on the line-wrapping layer for protective purposes. The rigid cover ring is externally tapered or gradually thinned down in its front and rear end portions to provide front and rear bevel surfaces. The rear bevel surface of the rigid cover ring is embedded under an annular fin which is formed in and out of a resilient skin layer at a position bordering on outer edges of the rear bevel surface, precluding possibilities of rear edges of the rigid cover ring hitting against a sharp-edged fore end of a tubular sheath member of a trocar particularly at the time of extraction of the endoscopic insertion rod from the trocar, and ensuring smooth retraction and protrusion of the endoscopic insertion rod into and out of a trocar.