Abstract: A flexible tube for use in an endoscope comprises a flexible basic tubular core structure including an outer meshwork tube, and a thermoplastic synthetic resin tube bonded to the outer meshwork tube of the tubular core structure in a manner such that the resin tube maintains an inherent compressive pre-stress in the finished flexible tube. An endoscope tube having flexibility which varies in a step-wise manner from one end of the tube to the other is obtained by integrally bonding two or more thermoplastic synthetic resin tube sections formed of respective resin materials having different hardnesses to the outer surface of the tubular core structure to form a coating layer in an analogous manner.

Abstract: A flexible tube for use in an endoscope comprises a flexible basic tubular core structure including an outer meshwork tube, and a thermoplastic synthetic resin tube bonded to the outer meshwork tube of the tubular core structure in a manner such that the resin tube maintains an inherent compressive pre-stress in the finished flexible tube. An endoscope tube having flexibility which varies in a step-wise manner from one end of the tube to the other is obtained by integrally bonding two or more thermoplastic synthetic resin tube sections formed of respective resin materials having different hardnesses to the outer surface of the tubular core structure to form a coating layer in an analogous manner.

Abstract: A flexible pipe assembly for an endoscope including a body of flexible material having both hollow grooves with side walls formed in outer wall portions thereof and cylindrical through-holes formed in a central portion of the body both of which extend along the axis of the body. Channel forming pipes are laterally arranged in any of the hollow grooves and cylindrical through-holes. The channel forming pipes may be bundled together to prevent them from being twisted. Various tube members such as multi-purpose tubes having plural channels which can convey air, water and suction as well as optical and electrical conductors may be positioned in the hollow grooves.

Abstract: An endoscope includes a forceps-control member movably mounted in a forward region of the elongate portion which is adapted to be inserted into a body cavity for selectively projecting and retracting forceps from and into the forward region of the insertion portion and an operating wire having one end connected to the forceps-control member and extending to the manipulator unit through an operating wire guide tube such that the projection and retraction of the forceps is controlled from the manipulator unit through the displacement of the operating wire.

Abstract: A device for preventing the observing objective lens window of an endoscope from collecting moisture by directing a small flow of air over the front surface of the observing objective lens window to form a layer of air which has the same temperature as the ambient atmosphere thereby stabilizing the temperature of the window. A control valve is provided which shuts off the flow of air in the event that the pressure within the body cavity in which the endoscope is inserted becomes too high due to the flow of air. A first embodiment of the control valve includes a cylinder and piston arrangement in which at a first position of the piston air is allowed to flow through the tube to the endoscope end. At a second position of the piston, air is vented directly to the atmosphere. In a second embodiment, a lateral hole is provided in the piston with the area of the hole and hence flow of air controlled by a screw the position of which determines the area of the lateral aperture.

Abstract: A flexible tube for use in an endoscope comprises a flexible basic tubular core structure and a homogeneous thermoplastic synthetic resin tube bonded to the outer surface of the tubular core structure to form a coating layer by positioning the synthetic resin tube tightly over the basic tubular core structure with a contact pressure therebetween and heating the synthetic resin tube to a temperature higher than a softening point of the thermoplastic synthetic resin forming the same. A flexible tube having flexibility which varies in a step-wise manner from one end of the tube to the other is obtained by integrally bonding as a whole two or more homogeneous thermoplastic synthetic resin tube sections formed of respective resin materials having different hardnesses to the outer surface of the tubular core structure to form a coating layer in an analogous manner.

Abstract: The high frequency incising device includes a flexible tubular member secured to a manipulating unit. The tubular member has an open ended tip portion and a pair of longitudinal spaced openings in the wall of the tube. An electrically conductive wire extends through the flexible tube passing outwardly thereof through a forward one of the longitudinal openings and being anchored to the flexible tube at a rearward one of the longitudinal openings. Such anchoring is accomplished by bending the wire toward the tip portion of the tube. A second bend portion in the outwardly exposed wire is directed away from the tip portion such that the outwardly exposed wire takes on the shape of a fan or sector. An opposite end of the wire is connected to an electrically conductive pipe that is movably disposed in the manipulating unit and the tube. An end of the movable pipe that projects beyond the manipulating unit is connected to an anchoring device that is movable with respect to the manipulating unit.

Abstract: A curvature control mechanism in an endoscope is disclosed. The endoscope is of the type which has a manipulator unit to which a flexible tubular member is connected and whose front end region constitutes a bendable portion. A knob member is rotatably mounted on the manipulator unit and control wires extend from the manipulator unit through the flexible member to the bendable portion so the latter can be bent by the wires in a selectively controlled manner through rotation of the knob. The curvature control mechanism includes a double cylinder type drum device including two drums fixedly mounted on a rotary shaft coupled to the knob.

Abstract: A tonometer having a construction whereby thermal expansion or contraction of the material forming the tonometer casing will have substantially no influence upon the precision of measurement of the instrument. The tonometer comprises a casing, a bellows mounted in a bottom portion of the casing, a rod resting on the bellows adapted to be axially shifted as the bellows expands and contracts, a base plate mounted above the bellows in the main portion of the casing, and an amplifying mechanism including a pointer mounted on the base plate in operative association with the rod for swinging the pointer. The base plate includes at least one leg forming an extension thereof which is fixed with respect to the casing so that the leg or legs constitute the sole means by which the base plate is fixedly mounted with respect to the casing. The rod rests on the bellows at a position closely adjacent to a position at which the base plate is fixed with respect to the casing.

Abstract: An endoscopic laser coagulator provides laser beam irradiation in an oblique direction relative to the axis of the insertion tube of the endoscope and includes an insertion tube having a leading end adapted to be introduced into the body and an elongate laser beam conducting fibre extending through the insertion tube. The laser beam conducting fibre is bent at a region proximate to the leading end of the insertion tube such that an oblique laser beam irradiation is obtained relative to the axis of the insertion tube.

Abstract: A device for changing a direction of the top end part of an endoscope in which a manual operating section is coupled to a top end part curving section through wires and the top end part curving section is curved vertically and horizontally by pulling the wires. A pair of wires are adapted to drive the top end part curving section vertically and horizontally, respectively, and a pair of drive members pull the wires directly or through intermediate members. Rotating knobs are integrally coupled to the pair of drive members so as to control the top end part curving section vertically and horizontally. A pair of brake drums confront one another, and a frictional member or brake shoe is mounted on a stationary member of the device in such a manner that it is movable with respect to the pair of brake drums. An external operating lever controls the movement of the brake shoe and the brake shoe abuts against the pair of brake drums by operation of the external operating lever so that simultaneous braking occurs.

Abstract: A direction changing device for a bioptic instrument having a protrusion provided at the top opening edge of an insertion passage into which a bioptic member or the like of an endoscope is inserted. The top opening edge is positioned in the vicinity of an objective lens of the endoscope or before the objective lens. The protrusion serves as a fulcrum to bend a pipe of bioptic instrument.A depressing member is located adjacent the protrusion to deflect an element of the instrument over the protrusion.The inserted member may be a device for taking samples or a fluid injection system. The instrument body may have a hood attached to the outer end with a direction changing protrusion on it. The hood may be rotatable relative to the instrument body. Deflection of the sample device of fluid stream is accomplished by positioning the deflection member relative to the passage in the instrument. A valve may be employed to seal the passage from contaminating elements.

Abstract: A suction device for an endoscope in which there is no need for the operator to close a suction pipe with his finger and in which cleaning and sterilizing are readily implemented. A suction path extends from a forceps insertion hole in a forceps receiver. A plug assembly is detachably inserted in the suction path in close contact therewith. The plug assembly includes a piston at least a portion of which is made of an elastic material and a cylinder member into which the piston is loosely fitted. The cylinder member has valve seats formed at first and second ends thereof while the piston is furnished with corresponding first and second abutting portions. An elastic extended member biases the piston outwardly. A suction hole is formed in the cylinder member through which suction pressure is communicated.

Abstract: In an endoscope having an optical fibre bundle for illumination communicating with an illumination window, an optical fibre bundle for observation communicating with a viewing window, an opening through which an implement, such as forceps for collection of vital tissue or tube for observation or photography of pancreatic duct or bile duct, is projected out, and a raiser adapted to bend the forward end of the implement to be guided into the visual field of the viewing window, wherein the opening is formed laterally of the viewing window and in parallel to the vertical plane including the optical central axis of the viewing window, and the raiser which is pivotally supported in the opening is adapted to be rotated in the vertical plane including the optical central axis of the viewing window and having a groove inclined towards the viewing window for guiding the implement into the visual field.

Abstract: An illumination device for photographing a portion of the body cavity to be examined with an endoscope having a light source using a discharge tube circuit for illuminating the portion to be examined and a mechanical shutter arranged in the optical path of illuminating light from the light source. A light quantity detecting circuit detects information on the brightness of illumination of the light source and a correct exposure time setting circuit together a correct exposure time estimating circuit receive the output from the light quantity detecting circuit. The closure of the mechanical shutter is controlled by the control operations of the correct exposure time setting circuit and correct exposure time estimating circuit. The discharge tube circuit comprises a time constant circuit, a relay circuit and a high voltage circuit. The high voltage circuit is controlled by the relay circuit to intermittently apply a voltage to start discharge until ignition takes place.

Abstract: A curvable tube assembly for an endoscope which can be inserted through insertion paths of different curvature and along narrow and zigzag paths in a body cavity. First and second curvable tube sections are arranged in succession with one another with each of the first and second curvable sections including a plurality of articulation rings supporting one another at at least two points so as to make the curvable sections bendable in at least two directions. The free end of the second curvable section is connected to a flexible tube. At least one pair of stay coils is provided having ends fastened to the connecting point of the first and second curvable sections. Pull strings are disposed in the stay coils having first ends fastened to the first curvable section and extending to a manual operation unit of the endoscope.

Abstract: An air and water supplying device for an endoscope, having air supplying tubes connecting an air pump and an endoscope provided with an air and water switching valve. A water storing tank is provided with a compressed air receiving inlet and a cleaning water delivering outlet, and a water supplying tube connects the endoscope and the water supplying tank to supply air and water to the top end part of said endoscope. An inlet receives the compressed air in the air pump in a water supplying path made up of the water supplying tube and a water pumping-up tube in the water storing tank in such a manner that the particular inlet is normally closed by an operating valve mechanism provided therefore. When the particular inlet is opened by the operating valve mechanism, the compressed air introduced into the particular inlet causes to discharge the water left in the water supplying path.

Abstract: An illuminating light control device for an endoscope for controlling both the intensity and hue of illuminating light over a wide range. A shutter mechanism is disposed between a discharge lamp light source and the receiving end of an optical fiber bundle. The shutter mechanism may be moved between at least three positions. At the first position, the light is allowed to pass directly from the light source to the optical fiber bundle and the light source is allowed to vary between its maximum and minimum limits. At the minimum limit, the shutter mechanism disposes a transmission light control means in the light path and the light source is returned to its maximum limit whereupon the output light to the optical fiber bundle is the same before the change as afterward. The light source can then be varied again between its maximum and minimum limits thereby effectively doubling the range of light output intensity.

Abstract: An electrical surgical knife which may be inserted into a body cavity of a patient through an endoscope in which electrical shock to the patient or user of the knife is prevented. A positive polarity electrode of the knife is disposed inside a flexible insulating tube. Around all but an end protruding active portion of the positive polarity electrode there is disposed a conductive metal sheath which is insulated therefrom. The metal sheath is electrically connected to a metal plate electrode which is adapted to be disposed in electrical contact with the skin of a patient.

Abstract: A slack absorbing device in the bending operation mechanism of an endoscope. Slack absorbing members are moved along the passage ways of connecting wires as the bending section is bent. Each slack absorbing member has a long groove extending along the direction of movement of said slack absorbing member and a theaded groove formed in a portion of the long groove. Threaded rods connect the ends of the wires extending to the bending section provided in the top end part of the endoscope in such a manner that the threaded rods are moved together with the wires at least when the wires are pulled towards the manual operating section. A part of each threaded groove is cut off so that the threaded rod can engage the threaded groove by aligning the theaded rod, in a direction corresponding to the direction of movement of the wire, and placing it into the groove.