Endoscope and bending tube unit of endoscope

Abstract

The present invention provides an endoscope and a curved tube unit of the endoscope, the endoscope having: a curved tube provided along a longitudinal axis; a wire that bends the bent tube; a first sheath into which the wire is inserted; and an annular plate disposed on the base end side of the bent tube. The plate material has a first annular surface on the front end side, a second annular surface on the base end side perpendicular to the longitudinal axis, and a hole penetrating through the first annular surface and the second annular surface and through which a wire is inserted, at least a part of the first sheath is disposed on the base end side of the plate material, and at least a part of the front end of the first sheath presses the peripheral edge portion of the hole on the second annular surface.

Description

Technical Field

[0001] The present invention relates to an endoscope and a bending tube unit of the endoscope, which has a bending tube that is bent by pulling or relaxing a wire. Background Art

[0002] In the past, endoscopes equipped with a bending tube (also called a bending portion) have been proposed. The bending tube changes the direction of the distal end by pulling or loosening a bending wire, thereby changing the observation direction of the endoscope. The bending wire is inserted from the operating portion of the endoscope into the bending tube.

[0003] In a flexible tube, a bending wire is inserted into a guide wire sheath, and a structure is sometimes employed to reduce friction between the sheath and the wire.

[0004] For example, when watertightness in the insertion portion can be ensured, a lubricant such as silicone oil or carbon powder may be used to reduce friction.

[0005] In addition, when the watertightness in the insertion portion cannot be ensured, an inner sheath having less friction with the wire than the sheath is sometimes provided. In this case, the wire is inserted into the sheath in a state of being inserted into the inner sheath.

[0006] For example, Japanese Patent No. 6028136 describes the use of a spiral sheath formed by winding a wire into a helical shape as a sheath for inserting a bending wire. Specifically, the bending wire is inserted into an inner spiral sheath, which is then inserted into an outer spiral sheath. The distal end of the outer spiral sheath is fixed to the inner surface of the distal end of the flexible tube, and the proximal end of the outer spiral sheath is fixed to a fixing plate within the operating unit. Summary of the Invention

[0007] An endoscope according to one embodiment of the present invention comprises: a bending tube arranged along a longitudinal axis extending from a base end side to a front end side; a wire configured to be pulled or relaxed to bend the bending tube; a first sheath through which the wire is inserted; and an annular plate arranged on the base end side of the bending tube, the plate having: a first annular surface on the front end side; a second annular surface on the base end side, which is perpendicular to the longitudinal axis; and a hole passing through the first annular surface and the second annular surface, and through which the wire is inserted, at least a portion of the first sheath being arranged on the base end side of the plate, and the front end of the at least a portion pressing a peripheral portion of the hole on the second annular surface.

[0008] An endoscope according to one embodiment of the present invention comprises: a bending tube arranged along a longitudinal axis extending from a base end side to a front end side; a wire configured to be pulled or relaxed to bend the bending tube; a first sheath through which the wire is inserted; and an annular plate arranged on the base end side of the bending tube, the plate having: a first annular surface on the front end side; a second annular surface on the base end side, which is perpendicular to the longitudinal axis; and a hole passing through the first annular surface and the second annular surface, the wire being inserted into the hole, at least a portion of the first sheath being arranged on the base end side of the plate, the front end of the at least a portion generating a friction force in a direction intersecting the longitudinal axis with a peripheral portion of the hole on the second annular surface.

[0009] An endoscope according to one embodiment of the present invention comprises: a bending tube arranged along a longitudinal axis extending from a base end side to a front end side; a wire configured to be pulled or relaxed to bend the bending tube; a first sheath; a second sheath inserted into the first sheath, and the wire inserted into the second sheath; and an annular plate arranged on the base end side of the bending tube, the plate having: a first annular surface on the front end side; a second annular surface on the base end side; and a hole passing through the first annular surface and the second annular surface, the wire inserted into the hole, at least a portion of the first sheath being arranged on the base end side of the plate, the front end of the at least portion pressing a peripheral portion of the hole on the second annular surface, the wire and the second sheath inserted into the hole, and the front end of the second sheath being arranged at a position closer to the front end side than the hole.

[0010] The bending tube unit of an endoscope according to one embodiment of the present invention comprises: a bending tube, which is arranged along a longitudinal axis extending from the base end side to the front end side; a wire, which is configured to be pulled or relaxed to bend the bending tube; a first sheath, in which the wire is inserted; and an annular plate, which is arranged on the base end side of the bending tube, the plate having: a first annular surface on the front end side; a second annular surface on the base end side, which is perpendicular to the longitudinal axis; and a hole, which passes through the first annular surface and the second annular surface, and in which the wire is inserted, at least a portion of the first sheath is arranged on the base end side of the plate, and the front end of the at least a portion presses the peripheral portion of the hole on the second annular surface. BRIEF DESCRIPTION OF THE DRAWINGS

[0011] Figure 1 This is a perspective view showing a configuration of the endoscope according to the first embodiment of the present invention with part omitted.

[0012] Figure 2 In the first embodiment described above, the cross-sectional view shows the structure of the bending wire at the connection portion between the bending tube and the flexible tube.

[0013] Figure 3 It is a partial perspective view showing the structure of the bending wire, inner sheath, sheath, and plate material in the first embodiment.

[0014] Figure 4 This is a cross-sectional view perpendicular to the longitudinal axis of the bent pipe near the plate in the first embodiment.

[0015] Figure 5 This is a cross-sectional view of a modified example of the plate material in the first embodiment, taken along a plane parallel to the longitudinal axis.

[0016] Figure 6 This is a cross-sectional view showing the structure of a second plate member disposed on the front end side of the curved pipe in the first embodiment from an oblique direction.

[0017] Figure 7 This is a cross-sectional view showing the lines inserted into the four holes of the second plate member in the first embodiment.

[0018] Figure 8 This is a cross-sectional view showing two wires respectively inserted into two holes of the second plate member in the first embodiment.

[0019] Figure 9 This is a perspective view showing a fixing member disposed in the operating portion in the first embodiment.

[0020] Figure 10 It is a cross-sectional view showing a part of the structure of the fixing member in the first embodiment.

[0021] Figure 11 This is a diagram showing a state in which the position for cutting the sheath is set according to the actual length of the flexible tube body in the first embodiment.

[0022] Figure 12 This is a side view showing the operating mechanism disposed in the operating portion in the first embodiment.

[0023] Figure 13 It is from Figure 12 The arrow A1 direction shows a partial perspective view of the operating mechanism of the first embodiment.

[0024] Figure 14 This is a diagram for explaining the process of fixing the bending wire to the operating mechanism in the first embodiment.

[0025] Figure 15 This is a diagram showing a state in which the sheath is held so as to press the plate and the fixing member in the first embodiment.

[0026] Figure 16This is a cross-sectional view showing the relationship between the sheath and the wire in the case where no inner sheath is provided in the first embodiment.

[0027] Figure 17 It is a diagram showing a configuration example of a sheath in a second embodiment of the present invention.

[0028] Figure 18 This is a diagram showing a first example of the swing angle of the wire in the third embodiment of the present invention.

[0029] Figure 19 This is a diagram showing a second example of the swing angle of the wire in the third embodiment.

[0030] Figure 20 It is a diagram showing a configuration example of a sheath in a fourth embodiment of the present invention.

[0031] Figure 21 This is a diagram showing a configuration example of a portion of the second annular surface of the plate material that contacts the front end of the sheath in the fifth embodiment of the present invention. DETAILED DESCRIPTION

[0032] Typically, a sheath through which a bending wire is inserted receives a pulling force when the bending wire is pulled to bend the bending tube. Therefore, the sheath is firmly fixed to the distal end of the flexible tube or the proximal end of the bending tube, for example, by welding.

[0033] However, welding and the like require skilled workers to use tools and are therefore not suitable for manufacturing low-cost endoscopes.

[0034] According to the embodiment described below, it is possible to provide an endoscope including a sheath through which a bending wire is inserted, which is suitable for manufacturing an inexpensive endoscope.

[0035] Hereinafter, embodiments of the present invention will be described with reference to the accompanying drawings. However, the present invention is not limited to the embodiments described below.

[0036] In the description of the drawings, identical or corresponding elements are denoted by the same reference numerals, as appropriate. It should also be noted that the drawings are schematic, and for simplicity of description, the length relationships, length ratios, and number of elements within a single drawing may differ from reality. Furthermore, multiple drawings may also contain portions that differ in length relationships, ratios, and numbers.

[0037] [First embodiment]

[0038] Figures 1 to 16 A first embodiment of the present invention will be described. Figure 1 This is a perspective view showing a configuration of the endoscope 1 according to the first embodiment with part of the configuration omitted.

[0039] The endoscope 1 is an insertion device having a portion to be inserted into a subject. The subject may be any of a living body such as a human or an animal, or a non-living body such as a machine or a building.

[0040] The endoscope 1 includes an insertion portion 2 , an operation portion 3 , and a universal cable 4 .

[0041] The insertion portion 2 is configured to be inserted into a subject and includes a distal end portion 2a, a bending tube 2b, and a flexible tube 2c in this order from the distal end side toward the proximal end side.

[0042] An imaging element, an imaging optical system, an illumination optical system, a nozzle 22a (see FIG. 2 ) are arranged at the distal end portion 2a. Figure 8 ), the channel front end side opening 21a (refer to Figure 8 ) etc. The illumination optical system irradiates illumination light to the subject. The imaging optical system forms an optical image of the subject. The imaging element performs photoelectric conversion on the optical image formed by the imaging optical system and generates an imaging signal. The nozzle 22a passes through the air and water supply channel 22 (refer to Figure 4 、 Figure 6 、 Figure 8 The gas and liquid transported by the imaging optical system are ejected toward the observation window at the front end of the imaging optical system. The channel front end opening 21a is the treatment instrument channel 21 (see Figure 2 、 Figure 4 、 Figure 6 The opening on the front end side of the device.

[0043] The bending tube 2b is a portion that can be bent in four directions, such as up, down, left, and right. The bending tube 2b is also called a bending portion. The bending tube 2b extends along the longitudinal axis O (refer to FIG. 1 ) extending from the base end side to the front end side of the endoscope 1. Figure 2 、 Figure 3 etc.) settings.

[0044] The flexible tube 2c is a flexible tube portion, also referred to as a flexible tube portion. The flexible tube 2c is provided along the longitudinal axis O at the proximal end of the curved tube 2b. While the endoscope 1 is exemplified herein as a soft endoscope having the flexible tube 2c, the endoscope 1 may also be a rigid endoscope in which the portion corresponding to the flexible tube 2c is rigid.

[0045] The operating section 3 is provided on the proximal end side of the flexible tube 2c of the insertion section 2. The operating section 3 is a portion for the user to operate the endoscope 1. The operating section 3 includes a grip 5, a bending operation knob 6, various operation switches 7, an air and water supply button 8a, a suction button 8b, and a treatment instrument insertion port 9.

[0046] The grip 5 is a portion where the user grips the endoscope 1 with the palm of his or her hand.

[0047] The bending operation knob 6 is an operating device for operating the bending of the bending tube 2b. The bending operation knob 6 is operated, for example, by the thumb of the hand holding the grip 5. When the bending operation knob 6 is operated, the bending wire 11 (see FIG. Figure 2 、 Figure 3 etc.) is pulled and the bending tube 2b is bent.

[0048] The bending operation knob 6 includes a vertical bending operation knob 6a and a horizontal bending operation knob 6b. The vertical bending operation knob 6a is operated to bend the bending tube 2b upward and downward, and the horizontal bending operation knob 6b is operated to bend the bending tube 2b leftward and rightward.

[0049] When the bendable tube 2b bends, the direction of the distal end portion 2a changes. Consequently, the imaging direction of the imaging element and the imaging optical system, as well as the irradiation direction of the illumination optical system, change. Furthermore, the bendable tube 2b bends to improve the insertability of the insertion portion 2 within the subject.

[0050] The operation switches 7 include push-button switches related to imaging. Specific examples of the operation switches 7 include a freeze button for temporarily pausing the monitor screen and a release button for capturing a still image.

[0051] The air and water supply button 8a is used to operate the air and water supply to the observation window of the front end 2a. The observation window is cleaned by water supply, and the cleaned liquid is blown away by air supply. The air and water supply are carried out through the air and water supply channel 22.

[0052] The suction button 8b is a button for performing suction from the distal end portion 2a into the subject. Suction from the subject is performed, for example, via the treatment instrument channel 21, which also serves as a suction channel. When suction is performed, for example, liquid or mucous membrane is sucked from the subject.

[0053] The treatment instrument insertion port 9 is the opening at the proximal end of the treatment instrument channel 21. A treatment instrument, such as a forceps, is inserted through the treatment instrument insertion port 9 into the treatment instrument channel 21. The distal end of the treatment instrument is guided through the treatment instrument channel 21 to the channel distal end opening 21a and protrudes into the subject. Various treatments are performed on the subject using the protruding distal end of the treatment instrument.

[0054] The universal cable 4 extends from a side surface, for example, on the proximal side, of the operation portion 3. A connector is provided at the extended end of the universal cable 4. The connector connects the endoscope 1 to an endoscope processor (video processor), a light source device, a suction pump, a water supply tank, and the like.

[0055] Figure 2 This is a cross-sectional view showing the structure of the bending wire 11 at the connection portion between the bending tube 2b and the flexible tube 2c in the first embodiment. Figure 3 It is a partial perspective view showing the structure of the bending wire 11 , the inner sheath 12 , the sheath 13 , and the plate material (plate body) 14 in the first embodiment. Figure 4 1 is a cross-sectional view perpendicular to the longitudinal axis O, showing the bent pipe 2b near the plate 14 in the first embodiment. Figure 4 This is a diagram obtained by observing the cross section toward the distal end direction along the longitudinal axis O.

[0056] The wire 11 is configured to bend the bendable tube 2b by being pulled or relaxed.

[0057] When the bending tube 2b is bendable in four directions, upward, downward, leftward, and rightward, the bending wire 11 includes an upward bending wire 11u, a downward bending wire 11d, a leftward bending wire 11l, and a rightward bending wire 11r.

[0058] The upper bending wire 11u is pulled to bend the bending tube 2b upward. The lower bending wire 11d is pulled to bend the bending tube 2b downward. The left bending wire 11l is pulled to bend the bending tube 2b leftward. The right bending wire 11r is pulled to bend the bending tube 2b rightward.

[0059] The bending wires 11u, 11d, 11r, and 11l for each direction are slidably inserted into four inner sheaths 12 (second sheaths). Furthermore, the four inner sheaths 12 through which the bending wires 11u, 11d, 11r, and 11l are inserted are each inserted into four sheaths 13 (first sheaths). Therefore, the wires 11 are inserted into the sheaths 13 via the inner sheaths 12.

[0060] The inner sheath 12 is formed of a thermoplastic elastomer as a resin, and may be formed of, for example, a PTFE (polytetrafluoroethylene) or PP (polypropylene)-based resin.

[0061] The sheath 13 is configured as, for example, an elastic spiral sheath and is assembled to the endoscope 1 in a state compressed relative to its natural length in the direction of the longitudinal axis O. The sheath 13 configured as a spiral sheath is spirally shaped along its entire length. However, the drawings simplify the illustration appropriately, showing the sheath 13 as a cylindrical shape except for the end portions (such as those near the plate 14). However, it is also possible to form only a portion of the sheath 13 in a spiral shape along its entire length.

[0062] Here, the friction coefficient between the inner sheath 12 and the wire 11 is smaller than the friction coefficient between the sheath 13 and the wire 11. In addition, by providing the inner sheath 12 that reduces friction, it is unnecessary to use lubricants such as silicone oil and carbon powder, and it is unnecessary to ensure watertightness within the insertion portion 2, resulting in a structure suitable for manufacturing low-cost endoscopes.

[0063] An annular plate 14 is disposed on the proximal end side of the bendable tube 2b. The plate 14 is a ring member that is separate from the bendable tube 2b.

[0064] like Figures 2 to 4 As shown, the plate 14 has a first annular surface 14a on the distal end side, a second annular surface 14b on the proximal end side, and a hole 14c penetrating the first annular surface 14a and the second annular surface 14b. The second annular surface 14b is perpendicular to the longitudinal axis O.

[0065] At least a portion of the sheath 13 is disposed on the base end side of the plate 14. Figure 2 and Figure 3 In the example shown, the sheath 13 is entirely disposed on the proximal side of the plate 14. The sheath 13 is assembled to the endoscope 1 in a compressed state as described above. Therefore, the distal end 13a of the sheath 13 presses the peripheral edge of the hole 14c in the second annular surface 14b due to the restoring force of the sheath 13 generated by compression.

[0066] That is, the front end 13a of the sheath 13 applies vertical resistance to the peripheral portion of the hole 14c on the second annular surface 14b. Therefore, frictional force in a direction intersecting the longitudinal axis O is generated between the front end 13a of the sheath 13 and the peripheral portion of the hole 14c on the second annular surface 14b.

[0067] At this time, because the second annular surface 14b is perpendicular to the longitudinal axis O, the front end 13a of the sheath 13 is in stable contact with the second annular surface 14b. Therefore, the plate 14 does not require a structure such as a long hole for inserting the sheath 13 to ensure stable contact between the front end 13a and the second annular surface 14b, and the thickness of the plate 14 in the direction of the longitudinal axis O can be reduced. Furthermore, if desired, the second annular surface 14b can be configured to intersect the longitudinal axis O at an angle.

[0068] The plate 14 is sandwiched between the front end 13a of the sheath 13 and the proximal end of the bendable tube 2b (for example, the guide member 16 disposed at the most proximal end among the guide members 16 disposed on the bendable tube 2b).

[0069] The plate 14 is neither welded nor bonded to the bendable tube 2b. The plate 14 abuts against the proximal end of the bendable tube 2b (the proximal end of the bendable tube 2b). The plate 14 is secured to the proximal end of the bendable tube 2b by the pressing force received from the sheath 13. Thus, the plate 14 functions as a sheath stopper that retains the distal end 13a of the sheath 13.

[0070] The wire 11 inserted into the inner sheath 12 is inserted into the hole 14c. Therefore, the front end 12a of the inner sheath 12 is arranged on the front side of the hole 14c.

[0071] The portion of the inner sheath 12 that is inserted into the hole 14c of the plate 14 is bonded to the hole 14c. The inner sheath 12 and the plate 14 are bonded together to form a unit. The plate 14 functions as a member that secures the distal end of the inner sheath 12. The proximal end of the inner sheath 12 is disposed within the operating portion 3 and is not secured.

[0072] Here, the inner sheath 12 is fixed at its distal end by adhesive bonding to the hole 14c of the plate 14 disposed in the bending tube 2b, leaving its proximal end free. This advantageously simplifies the manufacturing process for fixing the inner sheath 12.

[0073] However, it is not limited to this structure. For example, a structure may be adopted in which the base end side of the inner sheath 12 is fixed to a component (for example, a component described later) disposed in the operating portion 3. Figure 9 and Figure 10 The front end side is free. And, as long as there is no obstacle in use, the inner sheath 12 can be made into a free structure without being fixed.

[0074] The bending tube 2b includes a plurality of guide members 16 for holding (guiding) the wire 11 (see Figure 8 etc.). For example, the plurality of guide members 16 each serve as a bending block. Figure 2 As shown, the guide member 16 disposed on the most proximal end side of the bendable tube 2b is connected to the flexible tube body 2c1 of the flexible tube 2c.

[0075] The hole 14 c is provided at a position in a plane perpendicular to the longitudinal axis O that is different from the position at which the guide member 16 holds the wire 11 .

[0076] The guide member 16 includes, for example, a hole 16a that functions as a guide hole for the wire 11. The wire 11 is inserted into the hole 16a so as to be movable in a direction parallel to the longitudinal axis O. The position of the hole 16a in a plane perpendicular to the longitudinal axis O is the position at which the guide member 16 holds the wire 11.

[0077] By making the position of the hole 14c of the plate 14 and the position of the hole 16a of the guide member 16 different in the plane perpendicular to the longitudinal axis O (here, particularly the radial position centered on the longitudinal axis O), a swing angle is generated in the line 11 entering the curved tube 2b from the flexible tube 2c.

[0078] Thus, the wire 11 can be provided with a swing angle without providing an inclined long hole in the plate 14. Consequently, the thickness of the plate 14 in the direction of the longitudinal axis O can be reduced. Consequently, the length of the inflexible portion of the insertion portion 2 in the direction of the longitudinal axis O is shortened, thereby improving the insertability of the insertion portion 2.

[0079] exist Figure 2In the example shown, in a plane perpendicular to the longitudinal axis O, the hole 14c is provided closer to the longitudinal axis O than the hole 16a of the guide member 16 holding the wire 11. In this case, the hole 16a is located radially outward of the hole 14c with the longitudinal axis O as the center.

[0080] Therefore, the wire 11 swings radially outward when entering the bendable tube 2b from the flexible tube 2c, thereby more reliably preventing the wire 11 in the bendable tube 2b from contacting other internal components, including when the bendable tube 2b is bent.

[0081] like Figure 4 As shown, the width W14 of the second annular surface 14b around the hole 14c is greater than the width W13 of the front end 13a of the sheath 13. In this case, the entire surface of the front end 13a of the sheath 13 abuts the second annular surface 14b. Thus, the front end 13a of the sheath 13 and the second annular surface 14b are in stable contact.

[0082] Figure 5 This is a cross-sectional view of a modified example of the plate material 14 of the first embodiment cut along a plane parallel to the longitudinal axis O.

[0083] Figure 5 The plate 14 shown in the modified example has a groove 14d formed around the periphery of the hole 14c on the second annular surface 14b at the base end. The groove 14d is configured to abut against the distal end 13a of the sheath 13. The provision of the groove 14d prevents the distal end 13a from abutting against the plate 14 in a direction perpendicular to the longitudinal axis O, thereby stabilizing the abutment.

[0084] Figure 6 This is a cross-sectional view showing the structure of the second plate material 15 disposed on the front end side of the bent pipe 2b in the first embodiment from an oblique direction.

[0085] The endoscope 1 includes a second plate 15 disposed on the distal side of the bendable tube 2b. The second plate 15 is disposed so as to intersect the longitudinal axis O. The second plate 15 includes a distal surface 15a and a proximal surface 15b. The second plate 15 is disposed on the distal side of the bendable tube 2b such that the distal surface 15a and the proximal surface 15b are perpendicular to the longitudinal axis O.

[0086] However, in this embodiment, the upward bending wire 11u and the left bending wire 11l are integrally connected at the front end and constituted by a single wire 11a. In other words, a portion of the single wire 11a functions as the upward bending wire 11u, while the other portion of the single wire 11a functions as the left bending wire 11l.

[0087] The downward bending wire 11d and the rightward bending wire 11r are integrally connected at the distal end and constituted by a single wire 11b. In other words, a portion of the single wire 11b functions as the downward bending wire 11d, while the other portion functions as the rightward bending wire 11r.

[0088] Therefore, the bending wire 11 is bent in the vertical and horizontal directions by a total of two wires 11a and 11b.

[0089] In such a structure, the second plate member 15 further includes a plurality of holes penetrating the distal end side surface 15 a and the proximal end side surface 15 b .

[0090] Specifically, the second plate 15 has four holes (however, it is not limited to four and may be an even number of two or six or more) for inserting the wire 11a. The four holes are arranged around the longitudinal axis O (for example, Figure 6 ) in the clockwise direction of the axial direction, it has a first hole 15u1, a second hole 15u2, a third hole 15l2 and a fourth hole 15l1 in sequence.

[0091] The wire 11a is inserted from the base end of the second plate 15 into the first hole 15u1, and then sequentially into the second hole 15u2, the third hole 15l2, and the fourth hole 15l1. The wire 11l extends toward the base end of the second plate 15.

[0092] Figure 7 This is a cross-sectional view showing the line 11 a inserted through the four holes 15 u 1 , 15 u 2 , 15 l 2 , and 15 l 1 of the second plate member 15 in the first embodiment. Figure 8 This is a cross-sectional view showing two wires 11 a and 11 b respectively inserted into the two holes 15 u 1 and 15 d 1 of the second plate member 15 in the first embodiment.

[0093] Regarding the wire 11a, the wire 11u is inserted into the first hole 15u1 from the proximal end of the insertion portion 2 and extends as the first portion 11a1 of the wire 11a from the distal surface 15a. The first portion 11a1 of the wire 11a is arranged circumferentially on the distal surface 15a and inserted into the second hole 15u2.

[0094] The wire 11a inserted through the second hole 15u2 extends to the base end surface 15b as the second portion 11a2. The second portion 11a2 is arranged along the circumferential direction on the base end surface 15b and inserted through the third hole 15l2.

[0095] The wire 11a inserted through the third hole 1512 extends to the distal surface 15a as a third portion 11a3. The third portion 11a3 is arranged along the circumferential direction on the distal surface 15a and inserted through the fourth hole 1511.

[0096] The wire 11 a is inserted into the fourth hole 15 l 1 , and the wire 11 l extends toward the proximal end side of the insertion portion 2 .

[0097] In addition, the second plate 15 has four holes (however, it is not limited to four and may be an even number of two or six or more) for inserting the wire 11b as a plurality of holes. The four holes are arranged around the longitudinal axis O (for example, Figure 6 The first hole 15d1, the second hole 15d2, the third hole 15r2 and the fourth hole 15r1 are provided in sequence (in the clockwise direction of the ).

[0098] The wire 11b is inserted from the base end of the second plate 15 into the first hole 15d1, and then into the second hole 15d2, the third hole 15r2, and the fourth hole 15r1 in that order. The wire 11r extends toward the base end of the second plate 15.

[0099] Although the cross-sectional view is omitted for line 11b, Figure 7 Like the wire 11a shown in FIG. 1 , the wire 11d is inserted into the first hole 15d1 from the base end side of the insertion portion 2, and the surface 15a on the front end side serves as the first portion 11b1 of the wire 11b (see FIG. 1 ). Figure 6 The first portion 11b1 of the wire 11b is arranged along the circumferential direction on the surface 15a on the distal end side and is inserted into the second hole 15d2.

[0100] The wire 11b inserted into the second hole 15d2 serves as the second portion 11b2 (see Figure 6 The second portion 11b2 is arranged along the circumferential direction on the surface 15b on the base end side and is inserted into the third hole 15r2.

[0101] The wire 11b inserted into the third hole 15r2 serves as the third portion 11b3 (see Figure 6 The third portion 11b3 is arranged along the circumferential direction on the front end surface 15a and is inserted into the fourth hole 15r1.

[0102] The wire 11 b is inserted into the fourth hole 15 r 1 , and the wire 11 r extends toward the proximal end side of the insertion portion 2 .

[0103] Thus, the wires 11a and 11b are arranged in an M-shape relative to the second plate 15. Alternatively, a structure in which the wires 11a and 11b are formed in an M-shape on the second plate 15 may be prefabricated, and the bending wires 11 may be unitized. In this case, the unitized wires 11 are assembled into the endoscope 1.

[0104] like Figure 8As shown, the base end surface 15b of the second plate 15 abuts against the guide member 16, which is located at the distal end and also serves as a bending block. By applying tension in the tensile direction to the wires 11a and 11b, the second plate 15 is secured to the guide member 16. In this case, neither the bonding nor welding of the second plate 15 to the guide member 16 is necessary, reducing manufacturing costs.

[0105] Furthermore, since tension is applied to the wires 11 a and 11 b , frictional force acts between the wire 11 a and the second plate 15 and between the wire 11 b and the second plate 15 in the M-shaped portion.

[0106] Therefore, even if wire 11u is pulled, wire 11l is not pulled to the front end, and even if wire 11l is pulled, wire 11u is not pulled to the front end. Similarly, even if wire 11d is pulled, wire 11r is not pulled to the front end, and even if wire 11r is pulled, wire 11d is not pulled to the front end. Therefore, the second plate 15 functions as a wire stopper.

[0107] One wire 11a serves as both the upward bending wire 11u and the leftward bending wire 11l, while one wire 11b serves as both the downward bending wire 11d and the rightward bending wire 11r. This eliminates the need to secure the distal ends of each of the four wires to the distal end of the bending tube 2b (or the proximal end of the distal end portion 2a), thereby reducing manufacturing costs. Furthermore, by unitizing the two wires 11a and 11b with the second plate 15, assembly time and costs can be shortened.

[0108] Furthermore, although the configuration in which the endoscope 1 is bent in four directions using the two wires 11 a and 11 b has been described here, the endoscope 1 may also adopt a general configuration in which the endoscope 1 is bent in four directions using four independently provided bending wires.

[0109] Figure 9 This is a perspective view showing the fixing member 31 disposed in the operation unit 3 in the first embodiment. Figure 10 It is a cross-sectional view showing a part of the structure of the fixing member 31 in the first embodiment.

[0110] The operating unit 3 includes an operating unit body 3a, which also serves as an exterior. A fixing member (fixing body) 31 is secured to the operating unit body 3a using screws 32 or the like. The fixing member 31 bundles internal components such as the treatment instrument channel 21, the air and water supply channel 22, and the signal cable connected to the imaging element, securing the fixing member within the operating unit 3.

[0111] The fixing member 31 has a receiving surface 31 a. The receiving surface 31 a is configured as, for example, a surface perpendicular to the longitudinal axis O. At least a portion of the sheath 13 is disposed on the distal end side of the receiving surface 31 a.

[0112] exist Figure 9 as well as Figure 10 In the example shown, the sheath 13 is entirely disposed on the front end side of the receiving surface 31a. In this case, the base end 13b of the sheath 13 abuts against the receiving surface 31a. The inner sheath 12 extends from the base end 13b of the sheath 13 toward the base end side. The base end 12b of the inner sheath 12 (see Figure 9 ) is arranged at a position closer to the proximal end side than the fixing member 31. Moreover, as described above, the proximal end side of the inner sheath 12 is not fixed in the operation portion 3.

[0113] The sheath 13 is not fixed to other components, with one end of the sheath 13 merely being in contact with the second annular surface 14 b of the plate 14 and the other end of the sheath 13 being in contact with the receiving surface 31 a .

[0114] As described above, the sheath 13 is assembled to the endoscope 1 in a compressed state. Therefore, the proximal end 13b of the sheath 13 presses the receiving surface 31a of the fixing member 31 by the restoring force of the sheath 13 generated by the compression.

[0115] That is, the base end 13b of the sheath 13 applies vertical resistance to the receiving surface 31a. Therefore, a friction force in a direction intersecting the longitudinal axis O is generated between the base end 13b of the sheath 13 and the receiving surface 31a.

[0116] At this time, the base end 13b of the sheath 13 stably contacts the receiving surface 31a because the receiving surface 31a is perpendicular to the longitudinal axis O. Alternatively, the receiving surface 31a may be configured to obliquely intersect the longitudinal axis O as needed.

[0117] The fixing member 31 further includes a pressing structure 31b. The pressing structure 31b is located on the distal end of the receiving surface 31a of the fixing member 31. The pressing structure 31b abuts against the side surface of the sheath 13, preventing the sheath 13 from buckling. This prevents the sheath 13, the inner sheath 12 inserted therein, and the wire 11 from buckling, preventing any obstruction to the bending operation performed by the bending operation knob 6.

[0118] The filling rate of internal components, such as the treatment instrument channel 21, within the flexible tube 2c is higher than that within the operating portion 3. Consequently, other internal components within the flexible tube 2c prevent the sheath 13 from shifting perpendicularly to the longitudinal axis O. Consequently, the structure corresponding to the pressing structure 31b is not provided within the flexible tube 2c. In contrast, the operating portion 3, which has a lower filling rate of internal components than the flexible tube 2c, has more space available and therefore is provided with the pressing structure 31b.

[0119] However, as long as the sheath 13 , the inner sheath 12 , and the wire 11 are not offset in the direction perpendicular to the longitudinal axis O, the pressing structure 31 b of the operation portion 3 may be omitted.

[0120] Figure 11 This is a diagram showing a state in which the position for cutting the sheath 13 is set according to the actual length of the flexible tube body 2c1 in the first embodiment.

[0121] The actual length of the flexible tube main body 2c1 included in the flexible tube 2c may differ from the designed length due to product variations.

[0122] Furthermore, the sheath 13 is manufactured by cutting a long spiral sheath blank. If the actual length of the flexible tube 2c differs from the designed length, if the sheath 13 is cut to the designed length, the sheath 13 may not be properly compressed when assembled into the endoscope 1.

[0123] Therefore, the sheath 13 is adapted to the actual length of the flexible tube body 2c1, as shown in FIG. Figure 11 It is formed by cutting as shown.

[0124] exist Figure 11 In the process, one end of the manufactured flexible tube body 2c1 is aligned with the starting line LS, and the leading end of the spiral sheath blank is aligned with the starting line LS.

[0125] The design length of the flexible tube body 2c1 is the length from the start line LS to the flexible tube design line LD1. However, in the example shown, the actual length of the flexible tube body 2c1 is longer by a length L1 than the length from the start line LS to the flexible tube design line LD1.

[0126] On the other hand, the design length of the sheath 13 is the length from the start line LS to the sheath design line LD2. In this case, corresponding to the length L1 being longer than the design length of the flexible tube body 2c1, the cutting line LC for cutting the sheath 13 is set at a position longer than the sheath design line LD2 by the length L1, and the longitudinally long spiral sheath blank is cut.

[0127] By adopting such a manufacturing method, even when there is product variation in the length of the flexible tube body 2 c 1 , an appropriate compressed state can be maintained when the sheath 13 is assembled to the endoscope 1 .

[0128] Figure 12 This is a side view showing the operating mechanism 33 disposed in the operating portion 3 in the first embodiment. Figure 13 It is from Figure 12 The direction of arrow A1 shows a partial perspective view of the operating mechanism 33 of the first embodiment.

[0129] The operating portion 3 includes an operating mechanism 33 configured to receive an operation for pulling or loosening the wire 11. The proximal end of the wire 11 is fixed to the operating mechanism 33.

[0130] The operating mechanism 33 includes a pulley 34 and a pulley 35. The pulley 34 rotates about the rotation axis R in conjunction with the rotation of the vertical bending operation knob 6a. The pulley 35 rotates about the rotation axis R in conjunction with the rotation of the horizontal bending operation knob 6b.

[0131] In addition, the example in which the operating mechanism 33 is linked to the bending operation knob 6 is shown here, but the present invention is not limited to this structure. For example, the operating mechanism 33 may be electrically rotated by an actuator or the like in response to the operation of a joystick, or other appropriate structures may be adopted.

[0132] The pulley 34 is wound with the upper bending wire 11u and the lower bending wire 11d, and the base ends of the wires 11u and 11d are fixed. The pulley 35 is wound with the right bending wire 11r and the left bending wire 11l, and the base ends of the wires 11r and 11l are fixed.

[0133] The pulley 34 includes an upper bending wire winding chamber 34u and a lower bending wire winding chamber 34d at different positions in the direction of the rotation axis R. The upper bending wire winding chamber 34u and the lower bending wire winding chamber 34d are partitioned from each other by, for example, a flange or the like.

[0134] The pulley 35 includes a right bending wire winding chamber 35r and a left bending wire winding chamber 35l at different positions in the direction of the rotation axis R. The right bending wire winding chamber 35r and the left bending wire winding chamber 35l are separated from each other by, for example, a flange or the like.

[0135] For example, Figure 13 As shown, the wire 11r and the wire 11l cross at the base end of the pulley 35. After crossing, the wire 11r is wound once in the right bending wire winding chamber 35r and secured to the fixed portion 35a of the pulley 35 via the first positioning pin 36. The wire 11l, after crossing, is wound once in the left bending wire winding chamber 35l and secured to the fixed portion 35a of the pulley 35 via the second positioning pin 36. This structure prevents the wires 11r and 11l from overlapping, allowing them to transmit traction independently and relax independently.

[0136] Wires 11u and 11d are fixed to pulley 34 in the same manner as wires 11r and 11l. Specifically, wires 11u and 11d cross at the base end of pulley 34. After crossing, wire 11u is wound once in the upper bending wire winding chamber 34u and secured to the fixed portion 34a of pulley 34 via the third positioning pin 36. Wire 11d, after crossing, is wound once in the lower bending wire winding chamber 34d and secured to the fixed portion 34a of pulley 34 via the fourth positioning pin 36. This structure prevents wires 11u and 11d from overlapping, allowing them to transmit traction independently and relax independently.

[0137] Here, standard general-purpose parts may be used as the first to fourth positioning pins 36. By using general-purpose parts, the manufacturing cost of the endoscope 1 can be reduced compared to the case of using dedicated parts.

[0138] In addition, as referenced Figures 6 to 8 As described, when the wire 11u and the wire 11l are composed of a wire 11a, one end of the wire 11a (the base end of the wire 11u) is fixed to the pulley 34, extends toward the front end side, and is inserted into the flexible tube 2c and the bending tube 2b. After being arranged in an M shape on the second plate 15, it extends toward the base end side, is inserted into the bending tube 2b and the flexible tube 2c, and the other end (the base end of the wire 11l) is fixed to the pulley 35.

[0139] Similarly, when the wire 11d and the wire 11r are composed of a wire 11b, one end of the wire 11b (the base end of the wire 11d) is fixed to the pulley 34, extends toward the front end side, and is inserted into the flexible tube 2c and the bending tube 2b. After being arranged in an M shape on the second plate 15, it extends toward the base end side, is inserted into the bending tube 2b and the flexible tube 2c, and the other end (the base end of the wire 11r) is fixed to the pulley 35.

[0140] Figure 14 This is a diagram for explaining the process of fixing the bending wire 11 to the operating mechanism 33 in the first embodiment.

[0141] As described above, the wire 11 is fixed in the endoscope 1 in a state where tension is applied. The wire 11 is fixed in the endoscope 1 by, for example, the following steps.

[0142] The bending tube port fitting 37 , the fixing member 31 , and the operating mechanism 33 provided on the distal end side of the operating portion 3 are fixed to the auxiliary tool at positions spaced a predetermined distance apart from each other.

[0143] Then, the fixing portions 34 a and 35 a of the operating mechanism 33 are brought into contact with the anti-rotation tool 38 , thereby holding the pulleys 34 and 35 in a non-rotating state.

[0144] Then, the proximal end side of the wire 11 is wound around the winding jig 39 , and the winding jig 39 is rotated to wind the proximal end side of the wire 11 .

[0145] When the wire 11 is wound around the auxiliary tool 39, the bending tube 2b bends according to the winding amount. When the bending tube 2b reaches the maximum bending state, the wire 11 is stretched at a constant tension by adjusting the winding force of the auxiliary tool 39.

[0146] In this state, the positioning pin 36 is pushed into the fixing portions 34 a and 35 a to fix the proximal end side of the wire 11 .

[0147] By performing such operations on the wires 11u, 11d, 11r, and 11l, even when the bending tube 2b is in a straight state, a constant tension can be applied to the wires 11u, 11d, 11r, and 11l.

[0148] Here, if a certain tension is not applied to the wire 11, there is play. In this case, even if the bending operation is started, the bending will not start before the wire 11 is tightened, and the responsiveness of the bending to the user's operation is reduced.

[0149] In contrast, the wire 11 fixed in the above-mentioned process is in a state where a certain tension is applied, and therefore no play occurs, and the wire 11 can be bent with high responsiveness in response to user operations.

[0150] Figure 15 This is a diagram showing a state in which the sheath 13 is held so as to press the plate 14 and the fixing member 31 in the first embodiment.

[0151] The front end 13a of the sheath 13 contacts the second annular surface 14b of the plate 14, and the base end 13b contacts the receiving surface 31a of the fixing member 31. As shown by the double-headed arrows, the sheath 13 presses the plate 14 and the fixing member 31.

[0152] As a structure for such a function, the sheath 13 is described above as an example of a spiral sheath in a compressed state. However, it is not limited to a spiral sheath, and the sheath 13 may also be another structure having elasticity. For example, the sheath 13 may also be a cylindrical member formed of elastic rubber.

[0153] Furthermore, the sheath 13 does not need to be made of a typical elastic material (a compressible material). For example, in narrow-diameter endoscopes, a thin-walled metal tube is sometimes used as the tubular component forming the channel. Even if it is a metal tube, as long as it can be assembled into the endoscope 1 with both ends pressed, it will generate vertical resistance to the plate 14 and the fixing member 31, generating friction between the plate 14 and the fixing member 31 in a direction intersecting the longitudinal axis O. Therefore, the sheath 13 can also be a tubular component formed of a hard material, such as a metal tube.

[0154] Figure 16 This is a cross-sectional view showing the relationship between the sheath 13 and the wire 11 when the inner sheath 12 is not provided in the first embodiment.

[0155] When the wire 11 is pulled or relaxed, it moves in the direction of the length axis O. On the other hand, Figure 15 As shown, the sheath 13 is held by the plate 14 and the fixing member 31 and does not move in the direction of the longitudinal axis O. Therefore, when the wire 11 is pulled or loosened, the relative position of the wire 11 and the sheath 13 in the direction of the longitudinal axis O changes.

[0156] like Figure 16 As shown, assuming that the inner sheath 12 is not provided, if the relative positions of the wire 11 and the sheath 13 change, the wire 11 contacts the surface of the wire material of the sheath 13, which is a spiral sheath, and friction occurs, which may cause the wire 11 to wear. In addition, if the relative positions of the wire 11 and the sheath 13 change, the wire 11 contacts the edge of the end of the sheath 13 and friction occurs, which may cause the wire 11 to wear.

[0157] In contrast, in this embodiment, as described above, the distal end 12a of the inner sheath 12 is located distally of the hole 14c of the plate 14, and the proximal end 12b of the inner sheath 12 is located proximal of the proximal end 13b of the sheath 13.

[0158] That is, the inner sheath 12 is inserted throughout the entire length of the sheath 13, and the wire 11 does not directly contact the sheath 13. As described above, the friction coefficient between the inner sheath 12 and the wire 11 is smaller than the friction coefficient between the sheath 13 and the wire 11.

[0159] This can prevent the wire 11 from coming into contact with the surface or edge of the wire material of the sheath 13 and being worn. Furthermore, an increase in force due to friction when the wire 11 is pulled can be suppressed.

[0160] In addition, the front end 12a of the inner sheath 12 is arranged at a position closer to the front end than the hole 14c. Therefore, the wire 11 does not contact the sheath 13, nor does it contact the plate 14. This prevents the wire 11 from contacting the surface or edge of the plate 14 and being worn.

[0161] Furthermore, as described above, the base end 12b of the inner sheath 12 is disposed closer to the base end than the fixing member 31. Therefore, the wire 11 does not contact the fixing member 31. This prevents the wire 11 from contacting the surface or edge of the fixing member 31 and being worn.

[0162] According to the first embodiment, the sheath 13 is not fixed, with one end pressing against the plate 14 and the other end pressing against the fixing member 31. Therefore, when assembling the sheath 13 to the endoscope 1, there is no need for a skilled operator to perform welding or gluing operations using auxiliary tools. Consequently, the endoscope 1 having the sheath 13 through which the bending wire 11 is inserted is suitable for low-cost manufacturing.

[0163] Furthermore, the plate 14 is fixed by the pressing force of the sheath 13, and the second plate 15 is fixed by the tension of the wire 11, so welding and bonding are unnecessary.

[0164] Furthermore, by making the positions of the holes 14c of the plate 14 different from the positions of the holes 16a of the guide member 16, the wire 11 is given a swing angle. Therefore, the placement of the wire 11 can be made different within the bendable tube 2b and the flexible tube 2c, thereby increasing the degree of freedom in the placement of the internal components.

[0165] [Second embodiment]

[0166] Figure 17 1 is a diagram showing a configuration example of a sheath 13 in a second embodiment of the present invention. In the second embodiment, the same reference numerals are given to the same parts as in the first embodiment, and description thereof is omitted as appropriate. In the second embodiment, the differences from the first embodiment will be mainly described.

[0167] Part 13x of sheath 13 is disposed on the proximal side of second annular surface 14b of plate 14, and part 13y is disposed on the distal side of second annular surface 14b of plate 14. Part 13x is longer than part 13y in the longitudinal axis O direction.

[0168] A flange 13f protruding radially outward is provided at the front end of a portion 13x of the sheath 13. Therefore, even if the flange 13f is provided at the front end side of the sheath 13, it is not the front end 13a of the sheath 13 as a whole.

[0169] The flange 13f of the sheath 13 contacts the second annular surface 14b, pressing the plate 14. The surface of the flange 13f that contacts the second annular surface 14b is the tip 13a' of the portion 13x of the sheath 13. Therefore, the tip 13a' of the portion 13x of the sheath 13 serves as the portion that presses the plate 14.

[0170] Alternatively, a configuration may be adopted in which a protrusion or the like protruding radially outward from the sheath 13 is provided in place of the flange 13 f , and the plate 14 is pressed by the protrusion or the like.

[0171] In addition, when the sheath 13 is formed of an incompressible material, a configuration may be adopted in which a separate elastic member is provided so that the flange 13 f is pressed against the plate 14 by the elastic member.

[0172] Furthermore, instead of using the flange 13 f to press the plate 14 , a structure may be employed in which a portion of the outer peripheral surface of the sheath 13 is integrally bonded to the plate 14 so that the sheath 13 presses the plate 14 .

[0173] According to the second embodiment, even when the plate 14 is pressed by a portion of the front end 13a that is not the entire sheath 13, that is, the front end 13a' of a portion 13x of the sheath 13 disposed on the proximal end side of the plate 14, substantially the same effects as those of the first embodiment are achieved.

[0174] [Third embodiment]

[0175] Figure 18 and Figure 19 The third embodiment of the present invention is shown. In the third embodiment, the same reference numerals are given to the same parts as those in the first and second embodiments, and the description thereof is omitted as appropriate. In the third embodiment, the differences from the first and second embodiments will be mainly described.

[0176] As described above, by making the position of the hole 14 c of the plate 14 and the position of the hole 16 a of the guide member 16 different from each other, the wire 11 can be given a swing angle.

[0177] Figure 18 This is a diagram showing a first example of the swing angle of the wire 11 in the third embodiment.

[0178] In a plane perpendicular to the longitudinal axis O, the hole 14 c of the plate 14 is provided closer to the longitudinal axis O than the position where the guide member 16 holds the wire 11 , that is, the hole 16 a of the guide member 16 . Figure 18 The swing angle of the illustrated first example is substantially the same as the swing angle of the wire 11 described in the first embodiment.

[0179] In this case, the swing angle of the wire 11 becomes radially outward when it moves from the flexible tube 2c to the bendable tube 2b. By swinging the wire 11 radially outward, the internal space of the bendable tube 2b is expanded, which can increase the degree of freedom in the arrangement of the internal components in the bendable tube 2b.

[0180] Figure 19 This is a diagram showing a second example of the swing angle of the wire 11 in the third embodiment.

[0181] In a plane perpendicular to the longitudinal axis O, the hole 14 c of the plate 14 is provided at a position farther from the longitudinal axis O than the position where the guide member 16 holds the wire 11 , that is, the hole 16 a of the guide member 16 .

[0182] In this case, the swing angle of the wire 11 becomes radially inward when moving from the flexible tube 2c toward the bendable tube 2b. The bendable tube 2b tends to thicken its outer skin and increase its outer diameter. Therefore, by swinging the wire 11 radially inward, the interior of the bendable tube 2b is narrowed, thereby suppressing an increase in the outer diameter of the bendable tube 2b.

[0183] In addition, in the above description, the example of shifting the radial positions of the holes 14c and 16a is shown, but the present invention is not limited thereto and the circumferential positions of the holes 14c and 16a may be shifted. In this case, the arrangement of the built-in components can be easily adjusted.

[0184] According to the third embodiment, substantially the same effects as those of the first and second embodiments described above are achieved.

[0185] According to the third embodiment, by providing the swing angle on the wire 11 , the degree of freedom in arrangement of the built-in components can be increased, and adjustment of the arrangement of the built-in components can be facilitated, or an increase in the outer diameter of the bendable tube 2 b can be suppressed.

[0186] [Fourth embodiment]

[0187] Figure 20 The fourth embodiment of the present invention is shown. In the fourth embodiment, the same reference numerals are given to the same parts as those in the first to third embodiments, and the description thereof is omitted as appropriate. In the fourth embodiment, the differences from the first to third embodiments will be mainly described.

[0188] Figure 20 It is a diagram showing a configuration example of the sheath 13 in the fourth embodiment.

[0189] Part 13x' of sheath 13 is disposed on the distal side of receiving surface 31a of fixing member 31, and part 13y' is disposed on the proximal side of receiving surface 31a of fixing member 31. Part 13x' is longer than part 13y' in the direction of longitudinal axis O.

[0190] A flange 13g protruding radially outward is provided at the proximal end of a portion 13x' of the sheath 13. Therefore, even though the flange 13g is provided at the proximal end side of the sheath 13, it is not the proximal end 13b of the entire sheath 13.

[0191] The flange 13g of the sheath 13 contacts the receiving surface 31a of the fixing member 31, pressing the fixing member 31. The surface of the flange 13g that contacts the receiving surface 31a is the base end 13b' of the portion 13x' of the sheath 13. Therefore, the base end 13b' of the portion 13x' of the sheath 13 serves as the portion that presses the fixing member 31.

[0192] Alternatively, a configuration may be adopted in which a protrusion or the like protruding radially outward from the sheath 13 is provided in place of the flange 13 g so that the fixing member 31 is pressed by the protrusion or the like.

[0193] In addition, when the sheath 13 is formed of an incompressible material, a configuration may be adopted in which a separate elastic member is provided and the flange 13 g is pressed toward the fixing member 31 by the elastic member.

[0194] Furthermore, the sheath 13 may also be provided with Figure 17 The flange 13f shown and Figure 20 The flange 13g shown has both structures.

[0195] According to the fourth embodiment, even when the fixing member 31 is pressed by a portion that is not the base end 13b of the entire sheath 13, that is, the base end 13b' of a portion 13x of the sheath 13 arranged on the front end side of the fixing member 31, the same effects as those of the first to third embodiments described above are achieved.

[0196] [Fifth embodiment]

[0197] Figure 21 The fifth embodiment of the present invention is shown. In the fifth embodiment, the same reference numerals are given to the same parts as those in the first to fourth embodiments, and the description thereof is omitted as appropriate. In the fifth embodiment, the differences from the first to fourth embodiments will be mainly described.

[0198] Figure 21 This is a diagram showing a configuration example of a portion of the second annular surface 14 b of the plate 14 that comes into contact with the front end 13 a of the sheath 13 in the fifth embodiment.

[0199] As described above, the plate 14 is formed as a ring member for insertion of the built-in object. In this case, the ring width of the plate 14 in a plane perpendicular to the longitudinal axis O is preferably small so as not to hinder the insertion of the built-in object.

[0200] However, the plate 14 receives a pressing force from the front end 13a of the sheath 13. Therefore, the width W14 of the portion of the plate 14 that contacts the front end 13a is preferably greater than the width (outer diameter) W13 of the front end 13a of the sheath 13. Figure 21 In the example shown in column A, plate 14 is configured so that W14 ≥ W13 (specifically, W14 > W13 in the example shown). However, the width of plate 14, other than the portion contacting tip 13a, is smaller than W14. Therefore, the portion of plate 14 with width W14 protrudes radially inward.

[0201] according to Figure 21 The structural example shown in the column A can achieve both improved penetration of the built-in object and stable pressing force applied to the plate 14 from the front end 13a of the sheath 13.

[0202] in addition, Figure 21 The example shown in column B is to make the width of the portion of the plate 14 that contacts the front end 13a smaller than Figure 21 In this case, not all of the front end 13a contacts the second annular surface 14b of the plate 14, but only a portion of the front end 13a contacts the second annular surface 14b.

[0203] exist Figure 21 In the structure of column A, the front end 13a is in contact with the second annular surface 14b in a circular shape, and Figure 21In the structure of the B column, the front end 13a is in contact with the second annular surface 14b in a D shape (a part of the arc shape). In the case where the plate 14 receives a stable pressing force from the front end 13a of the sheath 13, it is also possible to adopt Figure 21 The structure shown in column B.

[0204] according to Figure 21 The structural example shown in the column B of FIG. 1 can reduce the filling rate of the built-in objects inserted into the plate 14. In addition, the material used to manufacture the plate 14 can be reduced.

[0205] on the other hand, Figure 21 The example shown in the C column is an example in which the width of the plate 14 in the plane perpendicular to the longitudinal axis O is set to a certain width equal to or greater than the width of the front end 13a of the sheath 13. As long as there is enough space in the flexible tube 2c and it does not hinder the insertion of the built-in object, it is also possible to adopt Figure 21 The structure shown in column C. Figure 21 In the structural example shown in the column C, when four holes 14c are provided in the plate 14, it is not necessary to perform alignment with the portion with a wider ring width.

[0206] According to the fifth embodiment, substantially the same effects as those of the first to fourth embodiments are achieved.

[0207] According to the fifth embodiment, the plate 14 having an appropriate structure can be selected based on the stability of the contact between the sheath 13 and the plate 14, the need to reduce the filling rate of the internal components, and the ease of forming the hole 14c in the plate 14.

[0208] In addition, the present invention is not directly limited to the above-mentioned embodiments. During the implementation stage, the present invention can be modified and concretized to the constituent elements within the scope of the main purpose of the invention. In addition, the multiple constituent elements disclosed in the above-mentioned embodiments can be appropriately combined to form various inventive methods. For example, some constituent elements can be deleted from all the constituent elements disclosed in the embodiments. In addition, constituent elements of different embodiments can also be appropriately combined. In this way, various modifications and applications can of course be made within the scope of the main purpose of the invention.

Claims

1. An endoscope, wherein: The endoscope comprises: a bending tube provided along a longitudinal axis extending from a base end side to a front end side; a wire configured to be pulled or relaxed to cause the bending tube to bend; a first sheath through which the wire is inserted; and an annular plate disposed on the base end side of the bending tube, The plate has: a first annular surface on the front end side; The second annular surface on the base end side is perpendicular to the longitudinal axis; and A hole passes through the first annular surface and the second annular surface, and the wire is inserted into the hole, at least a portion of the first sheath is arranged on the base end side of the plate, and the front end of the at least a portion presses the peripheral portion of the hole on the second annular surface.

2. The endoscope according to claim 1, wherein The first sheath has elasticity, and the front end of the at least a portion of the first sheath presses the peripheral edge portion of the hole in the second annular surface due to a restoring force generated by compression of the first sheath in the direction of the longitudinal axis.

3. The endoscope according to claim 2, wherein: The first sheath is a spiral sheath.

4. The endoscope according to claim 1, wherein The endoscope further includes a second sheath inserted into the first sheath, and the wire is inserted into the second sheath. The second sheath is inserted into the hole, and the front end of the second sheath is arranged on the front end side of the hole.

5. The endoscope according to claim 4, wherein: The portion of the second sheath inserted into the hole is bonded to the hole.

6. The endoscope according to claim 4, wherein: The coefficient of friction between the second sheath and the wire is less than the coefficient of friction between the first sheath and the wire.

7. The endoscope according to claim 6, wherein: The second sheath is formed of resin.

8. The endoscope according to claim 1, wherein The first sheath is entirely disposed on the base end side of the plate member, and the front end of the first sheath presses the peripheral edge portion of the hole in the second annular surface.

9. The endoscope according to claim 8, wherein: The width of the second annular surface at the peripheral edge of the hole is greater than the width of the front end of the first sheath. The entire surface of the front end of the first sheath abuts against the second annular surface.

10. The endoscope according to claim 1, wherein The bending tube has a guide member for holding the wire, The hole is provided at a position different from a position at which the guide member holds the wire in a plane perpendicular to the longitudinal axis.

11. The endoscope according to claim 10, wherein: The hole is provided at a position closer to the longitudinal axis than a position at which the guide member holds the wire in a plane perpendicular to the longitudinal axis.

12. The endoscope according to claim 10, wherein: The hole is provided at a position farther from the longitudinal axis than a position at which the guide member holds the wire in a plane perpendicular to the longitudinal axis.

13. The endoscope according to claim 1, wherein The endoscope further includes: a flexible tube provided on the proximal end side of the bending tube along the longitudinal axis; and an operation portion provided on the proximal end side of the flexible tube. The operating portion has a fixing component having a receiving surface perpendicular to the longitudinal axis. At least a portion of the first sheath is disposed on the distal end side of the receiving surface, and a proximal end of the at least a portion presses the receiving surface.

14. The endoscope according to claim 13, wherein: The first sheath is entirely disposed on the distal end side of the receiving surface, and the proximal end of the first sheath presses the receiving surface.

15. The endoscope according to claim 13, wherein The fixing member includes a pressing structure portion on the front end side of the receiving surface, which contacts a side surface of the first sheath to prevent buckling of the first sheath.

16. The endoscope according to claim 13, wherein The operating portion includes an operating mechanism configured to receive an operation of pulling or loosening the wire. The base end side of the wire is fixed to the operating mechanism.

17. The endoscope according to claim 16, wherein: The operating mechanism includes a pulley around which the wire is wound. The base end side of the wire is fixed to the pulley via a positioning pin.

18. The endoscope according to claim 1, wherein The endoscope further includes a second plate member disposed on the distal end side of the bending tube so as to intersect the longitudinal axis. The second plate has a first hole, a second hole, a third hole, and a fourth hole that pass through the front end side surface and the base end side surface of the second plate in order around the longitudinal axis. The wire is inserted into the first hole, the second hole, the third hole, and the fourth hole in sequence from the base end side of the second plate member, and extends toward the base end side of the second plate member.

19. An endoscope, wherein: The endoscope comprises: a bending tube provided along a longitudinal axis extending from a base end side to a front end side; a wire configured to be pulled or relaxed to cause the bending tube to bend; a first sheath through which the wire is inserted; and an annular plate disposed on the base end side of the bending tube, The plate has: a first annular surface on the front end side; The second annular surface on the base end side is perpendicular to the longitudinal axis; and A hole passes through the first annular surface and the second annular surface, the wire is inserted into the hole, at least a portion of the first sheath is arranged on the base end side of the plate, and the front end of the at least a portion generates a friction force in a direction intersecting the longitudinal axis between the peripheral portion of the hole on the second annular surface.

20. An endoscope, wherein: The endoscope comprises: a bending tube provided along a longitudinal axis extending from a base end side to a front end side; a wire configured to be pulled or relaxed to cause the bending tube to bend; First sheath; a second sheath inserted into the first sheath, and the wire is inserted into the second sheath; and an annular plate disposed on the base end side of the bending tube, The plate has: a first annular surface on the front end side; The second annular surface on the base end side; and a hole penetrating the first annular surface and the second annular surface, the wire being inserted into the hole, at least a portion of the first sheath being disposed on the base end side of the plate, the front end of the at least a portion pressing the peripheral edge of the hole on the second annular surface, The wire and the second sheath are inserted into the hole, and the front end of the second sheath is arranged on the front end side of the hole.

21. A curved tube unit for an endoscope, wherein: The bending tube unit of the endoscope includes: a bending tube provided along a longitudinal axis extending from a base end side to a front end side; a wire configured to be pulled or relaxed to cause the bending tube to bend; a first sheath through which the wire is inserted; and an annular plate disposed on the base end side of the bending tube, The plate has: a first annular surface on the front end side; The second annular surface on the base end side is perpendicular to the longitudinal axis; and A hole passes through the first annular surface and the second annular surface, and the wire is inserted into the hole, at least a portion of the first sheath is arranged on the base end side of the plate, and the front end of the at least a portion presses the peripheral portion of the hole on the second annular surface.

Images