Disclosed is a construction of an endoscopic fluid changing device which, attached to an endoscope, regulates the flow of a fluid in a channel of the endoscope. The fluid changing device comprises a cylindrical casing having a suction port, in the side wall thereof, a channel pipe provided in the center of the casing, and having an opening at the upper end portion thereof, the lower end portion of the channel pipe being connected to an instrument channel, extending to the distal end portion of the endoscope, a cap member covering the opening of the channel pipe, a piston disposed between the casing and the channel pipe, and capable of vertical motion, a spring for urging the piston upward, first valve device provided at the upper portion of the piston, and adapted to open or close a first passage as the piston is operated, the first passage extending from the suction port to the outside of the casing, and second valve device provided at the lower portion of the piston, and adapted to close or open a second passage, in contrast with the first passage, as the piston is operated, the second passage extending from the suction port to the instrument channel.

In a suction control unit used with an endoscope having a channel, a tubular main body has a suction port in the side wall and a bore and in the bore, an inner tube with a through hole communicating with the channel of the endoscope is installed. A sliding tube is located slidably in the axial direction between the main body and the inner tube. The proximal end portion of an operating lever is secured at an upper position of the sliding the tube while the distal end portion extends outside the main body. This suction control unit is equipped with passage switching unit to connect the suction port with the endoscope channel or the outside of the main body through a relief port when the operating lever is operated.

According to the method for terminating a cable and the apparatus used therefor of the present invention, first the thermosetting resin layer of the cable is heat-cured, for example, by laser beam. The heat-cured thermosetting resin layer is lowered in stress and strain at rupture and hence can be easily cut and then this thermosetting resin layer is cut and peeled off.

A suction operating apparatus in an endoscope consisting of an outer cylinder connected to a sucking channel of the endoscope, an inner cylinder removably fitted to this outer cylinder and having a sucking hole on the side, a valve body made of an elastic material and having a slit in a closing part provided in the lower end part of this inner cylinder and closing a lower end opening of the inner cylinder, an operating member provided so as to be free to advance and retreat within the inner cylinder, and to be pushed into the slit of the valve body to open and close this slit, thus forming a fluid flow path communicating with the sucking hole in the axial direction, and an elastic cover for elastically returning the operating member to the fixed position from the pushed-in position.

A gas pressure neutralizing device for use with a working channel of an inspection instrument. The device comprises means for providing a first gas pressure buffer, a second gas pressure buffer, a chamber formed therebetween and means for reducing the pressure in the chamber whereby gases are substantially prevented from exiting the instrument through a working inlet of the device at an elevated pressure or high velocity.