JP2009279292A - Endoscope - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide an endoscope capable of preventing breaking and failure of a flexible endoscopic element by reducing the friction between an expanding connection ring and the flexible endoscopic element. <P>SOLUTION: In the endoscope, a flexible insertion part is provided at the distal end of an operating part, the expanding connection ring having a tapered hole expanded toward the internal space in the operating part is fixed to an operating part side end of a flexible tube located inside the insertion part, and the continuous flexible endoscopic element is inserted into the internal space in the operating part, the expanding connection ring, and into the flexible tube. The expanding connection ring is composed of a metal outer ring fixed to an end of the flexible tube and a synthetic resin inner ring located on the inner side of the metal outer ring to be in contact with the flexible endoscopic element. A small-diameter tapered hole part at least on the flexible tube side of the tapered hole is formed in the inner ring. <P>COPYRIGHT: (C)2010,JPO&INPIT

Description

  The present invention relates to an endoscope including a flexible tube having flexibility in an insertion portion.

Medical and industrial endoscopes are provided with an insertion portion that is smaller in diameter and more flexible than the operation portion at the distal end of the operation portion in order to facilitate insertion of a bent path into an observation target. . Generally, a flexible tube is positioned in the insertion portion, and a metal diameter expansion connection having a tapered hole that expands toward the inner space of the operation portion at the operation portion side end portion of the flexible tube. The ring is fixed, and a continuous flexible endoscope element such as an air / water supply tube or a CCD signal cable is inserted through the internal space of the operation section, the enlarged diameter connection ring and the flexible tube. Such endoscopes are described in Patent Documents 1 to 3, for example.
Japanese Patent Laid-Open No. 08-187221 Japanese Patent Application Laid-Open No. 11-178783 Japanese Patent Laid-Open No. 2002-345741

  However, in an endoscope represented by, for example, a nasal endoscope, that is, an endoscope having a thin flexible tube, the movable space inside the operation unit increases as the diameter decreases, so the insertion portion is curved. Sometimes, the flexible endoscope element is rubbed by the enlarged connection ring extending from the flexible tube to the inside of the operation unit, and the flexible endoscope element may be damaged or broken. FIG. 5 shows an endoscope having a conventional structure, in which a contact portion between a metal diameter-expanded connecting ring 50 'and a flexible endoscope element E' is indicated by a broken line.

  An object of the present invention is to provide an endoscope that can reduce friction between the enlarged connection ring and the flexible endoscope element and prevent damage and failure of the flexible endoscope element.

  According to the present invention, a portion of the diameter expansion connecting ring that comes into contact with the flexible endoscope element is made of a synthetic resin, and at least a part of a tapered hole whose diameter is expanded toward the internal space of the operation portion is formed in the portion. Thus, the present invention has been completed by paying attention to the fact that the friction between the enlarged connection ring and the flexible endoscope element can be reduced by reducing the contact area with the flexible endoscope element.

  That is, according to the present invention, an insertion portion having a smaller diameter and flexibility than the operation portion is provided at the distal end of the large diameter operation portion, and a flexible tube is located in the insertion portion. A diameter expansion connection ring having a tapered hole that expands toward the internal space of the operation section is fixed to the operation section side end, and the flexible space that is continuous in the operation section inner space, the diameter expansion connection ring, and the flexible tube is fixed. In an endoscope through which an endoscopic element is inserted, the above-mentioned enlarged diameter connection ring is positioned inside the metal outer ring and the metal outer ring fixed to the end of the flexible tube. It is composed of an inner ring made of synthetic resin that comes into contact with the mirror element, and a small diameter tapered hole portion of at least the flexible tube side of the tapered hole is formed in the inner ring.

  All the tapered holes can be formed in the inner ring. Alternatively, a small-diameter tapered portion on the flexible tube side can be formed in the inner ring, and a large-diameter tapered hole portion on the side can be formed in the outer ring.

  The inner ring made of synthetic resin is preferably screwed to the outer ring made of metal by a screw centered on the axis of the flexible tube.

  The inner ring made of synthetic resin is formed with a reverse taper hole that is positioned closer to the flexible tube side than the small diameter tapered hole portion and expands the diameter toward the flexible tube side. More preferably, the portion and the reverse tapered hole are connected by a smooth circular arc surface. According to this aspect, the flexible tube side of the inner ring does not contact the flexible endoscope element due to the reverse tapered hole, and locally contacts the flexible endoscope element at the cross-sectional arc surface of the inner ring. The burden (stress) applied to the flexible endoscope element when the insertion portion is curved can be reduced. It is practical that the inner diameter of the arcuate section is equal to or larger than the inner diameter of the flexible tube.

  The synthetic resin constituting the inner ring of the expanded connection ring can be, for example, a tetrafluoroethylene resin, polyacetal, polyamide, or polyolefin. If these synthetic resin materials are used, a friction coefficient becomes small compared with the case where the inner ring is made of a metal material, and friction generated between the flexible endoscope elements can be suppressed.

  According to the present invention, the inner ring contacting the flexible endoscope element of the diameter expansion connecting ring is made of a synthetic resin having a smaller friction coefficient than that of the metal material, and has a taper that expands toward the inner space of the operation portion. Since the hole has a small-diameter tapered hole portion on at least the flexible tube side, the friction between the enlarged-diameter connecting ring and the flexible endoscope element is reduced, and damage and failure of the flexible endoscope element can be prevented. An endoscope can be provided.

  An embodiment of an endoscope according to the present invention will be described with reference to FIGS. 1 to 4. An electronic endoscope 10 shown in FIG. 1 is a medical endoscope, and includes an insertion portion 11 to be inserted into a body cavity and an operation portion 12 connected to the base side thereof.

  The insertion portion 11 includes a distal end portion 13, a bending portion 14, and a flexible tube portion 15 in order from the distal end side, and is connected to the operation unit 12 via the flexible tube portion 15. The distal end portion 13 has a distal end portion main body (not shown) made of a rigid member. The distal end portion main body has an objective lens holding hole, a light distribution lens holding hole, an air / water supply channel outlet, a treatment instrument insertion channel outlet (not shown). Etc. are formed. An objective lens for image formation and a light distribution lens for illumination are held in the objective lens holding hole and the light distribution lens holding hole, and a CCD (imaging device) (not shown) is arranged behind the objective lens. The bending portion 14 is arbitrarily bent by a turning operation of the bending operation knobs 20A and 20B provided in the operation unit 12. The bending state of the bending portion 14 can be fixed by operating the lock knob 21A and the lock lever 21B provided in the operation portion 12. The lock knob 21A restricts the rotation of the bending operation knob 20A that bends the bending portion 14 in the left-right direction, and the lock lever 21B restricts the rotation of the bending operation knob 20B that causes the bending portion 14 to bend in the vertical direction. As shown in FIG. 2, the outer shape of the flexible tube portion 15 is configured by a flexible tube (outer tube) 39 having flexibility. A partial region on the proximal end side (insertion portion 12 side) of the flexible tube 39 is covered with a conical anti-fold rubber tube 44, and the flexible tube 39 is bent excessively by the anti-fold rubber tube 44. Not regulated. The portion of the flexible tube portion 15 that is covered with the bend preventing rubber tube 44 is not inserted into the observation target.

  A universal tube 22 extends from the operation unit 12, and a connector unit 23 connected to a processor (not shown) is provided at the end of the universal tube 22. The connector portion 23 faces the signal transmission cable 30 and the end of the light guide 31 shown in FIG. 2, the inlet of the air supply channel 32 and the water supply channel 33, and the like, by connecting the connector portion 23 to the processor, The signal transmission cable 30, the light guide 31, the air supply channel 32, and the water supply channel 33 are connected to an image processing device on the processor side, a light source, an air supply source, and a water supply source, respectively. The image of the observation object that has entered the light receiving surface of the CCD from the objective lens at the distal end portion 13 is photoelectrically converted by the CCD, and passes through the signal transmission cable 30 arranged from the CCD to the connector portion 23 at the end of the universal tube 22. And sent to the processor as an electronic image. The processor can display an electronic image on a monitor (not shown) or record it on an image recording medium. The operation unit 12 is provided with a plurality of remote operation button switches 35 for performing remote operations related to image processing. Further, illumination light from a light source provided in the processor is given to the light distribution lens of the distal end portion 13 through the above-described light guide 31 disposed from the connector portion 23 of the universal tube 22 to the distal end portion 13.

  The operation unit 12 is provided with an air / water button 36, a treatment instrument insertion port protrusion 37, and a suction button 38. When the air / water supply button 36 is pushed in, the water supply source provided on the processor side communicates with the water supply channel 33 and water is supplied into the water supply channel 33. A nozzle is provided toward the objective lens at the outlet of the water supply channel 33 provided at the tip portion 13, and a liquid such as washing water sent to the water supply channel 33 is ejected from the nozzle toward the objective lens. Wash the objective lens. Further, a hole (not shown) is provided on the upper surface of the air / water supply button 36. When this hole is closed, the positive pressure of the air supply source provided on the processor side acts on the air supply channel 32 to send air. . Similarly to the water supply channel 33, a nozzle is provided at the outlet of the air supply channel 32 provided at the distal end portion 13 toward the objective lens, and when air is sent to the air supply channel 32, the nozzle to the objective lens is provided. Air can be ejected toward the objective lens to remove water droplets of cleaning water and other liquids such as body fluids.

  The treatment tool insertion port projection 37 is for inserting a treatment tool such as forceps or a high-frequency cautery treatment tool, and the treatment tool insertion channel 34 (FIG. 2) extends from the treatment tool insertion port projection 37 toward the inside of the endoscope. ) Is extended. The treatment instrument insertion channel 34 communicates with a treatment instrument insertion channel outlet formed at the distal end portion 13, and the treatment instrument inserted from the treatment instrument insertion port projection 37 passes through the treatment instrument insertion channel 34 and is treated as a treatment instrument insertion channel. Can protrude from the outlet. The treatment instrument insertion channel 34 is also connected to a negative pressure source (suction source) (not shown) provided outside the electronic endoscope 10. Therefore, it is possible to insert a treatment tool such as forceps through the treatment tool insertion port projection 37 and apply a negative pressure to the treatment tool insertion channel 34 through a negative pressure source. When the treatment instrument insertion channel 34 is used as a suction conduit, the suction button 38 is pressed. Then, the negative pressure source side pipe line and the treatment instrument insertion channel 34 are communicated with each other, so that negative pressure acts on the treatment instrument insertion channel 34 and fluid such as a body fluid can be sucked from the treatment instrument insertion channel outlet.

  Endoscopic elements (built-in) that pass through the bending portion 14, the flexible tube portion 15, and the operation portion 12, that is, the signal transmission cable 30, the light guide 31, the air supply channel 32, the water supply channel 33, and the treatment. The instrument insertion channel 34 has flexibility so as to correspond to the bending operation of the bending portion 14 and the deformation of the flexible tube portion 15. As will be described below, the electronic endoscope 10 according to the present embodiment can reduce friction generated in the flexible endoscope element at the connecting portion from the flexible tube portion 15 to the operation portion 12.

  2 shows the connecting portion of the flexible tube portion 15 and the operation portion 12 as viewed from the side, and FIGS. 3 and 4 show the base end side (the operation portion side end portion of the flexible tube portion 15). ) Is enlarged.

  The flexible tube 39 has a form in which an outermost flexible tube outer skin 40, a mesh tube 41, a spiral tube 42, and an inner tube 43 made of resin are stacked. The flexible tube outer skin 40 is made of an elastomer such as polyurethane, and the inner tube 43 is made of a resin material, each of which has non-ventilating (and non-water-permeable) and non-conductive properties. The spiral tube 42 disposed between the flexible tube outer skin 40 and the inner surface tube 43 imparts a certain bending rigidity to the flexible tube 39. Further, the mesh tube 41 is formed by braiding a stainless metal wire, and mainly prevents the flexible tube 39 from extending in the longitudinal direction. The diameter φ of the flexible tube 39 varies depending on the use of the endoscope. For example, in a small-diameter endoscope represented by a nasal endoscope, the flexible tube portion 15 has a very small diameter of about φ = 5 mm to 6 mm.

  As shown in FIGS. 2 to 4, an enlarged diameter connection ring 50 that connects the flexible tube 39 to the operation unit 12 is fixed to the base end (operation unit side end) of the flexible tube 39. The enlarged diameter connection ring 50 includes a metal outer ring 51 having an uneven surface 51a formed on the outer peripheral surface, which is joined to the inner peripheral surface on the distal end side of the operation unit 12, and a flexible internal view located inside the outer ring 51. The inner ring 52 is made of a synthetic resin and comes into contact with the mirror element. The inner ring 52 is not flexible as a whole, and supports the flexible tube 39 and the bend preventing rubber tube 44. The inner ring 52 is screwed to the outer ring 51 by a screw 53 centered on the axis C of the flexible tube 39.

  The enlarged diameter connection ring 50 is provided with a tapered hole 54 whose diameter is increased toward the inner space of the operation portion 12 on the inner peripheral surface thereof. The tapered hole 54 of this embodiment is continuously formed on the inner peripheral surface of the inner ring 52 from the small diameter tapered hole portion on the flexible tube 39 side to the large diameter tapered hole portion on the operation portion 12 side. Further, the inner circumferential surface of the inner ring 52 is provided with a reverse tapered hole 55 that is positioned closer to the flexible tube 39 than the small-diameter tapered hole portion of the tapered hole 54 and is expanded toward the flexible tube 39. The reverse tapered hole 55 and the small diameter tapered hole portion of the tapered hole 54 are connected by a smooth circular arc surface 56. The reverse tapered hole 55 creates a clearance space that prevents contact with the endoscope element at the connection end with the flexible tube 39.

  Here, the end diameter (inner diameter of the end portion on the side of the flexible tube 39) φ2 of the reverse tapered hole 55 is larger than the inner diameter φ of the flexible tube 39 and the inner diameter φ3 of the large diameter tapered hole portion of the tapered hole 54. It is set small. Further, the inner diameter φ4 of the circular arc surface 56 is set to be equal to or larger than the inner diameter φ of the flexible tube 39. The inner diameter φ1 of the small-diameter tapered hole portion of the tapered hole 54 is smaller than the inner diameter φ3 of the large-diameter tapered hole portion and is approximately the same as the inner diameter φ4 of the circular arc surface 56 (φ ≦ φ1≈φ4 <φ3, φ <φ2 <Φ3). In other words, the inner peripheral surface of the enlarged diameter connection ring 50 (inner ring 52) has a minimum inner diameter at the cross-sectional arc surface 56.

  Therefore, the diameter expansion connecting ring 50 extending from the flexible tube 39 to the internal space of the operation unit 12 is a cross-sectional arc surface 56 and is in local contact with the flexible endoscope element inserted therethrough. In other words, the contact area between the enlarged diameter connecting ring 50 and the flexible endoscope element is suppressed by making point contact with the circular arc surface 56 in cross section. Furthermore, since the inner ring 52 of the enlarged diameter connection ring 50 that is a contact portion is made of a synthetic resin, the diameter of the expanded endoscope element is larger than when the flexible endoscope element is in full contact with the enlarged diameter connection ring made of metal. Friction generated between the connection ring 50 (circular arc surface 56) and the flexible endoscope element can be reduced. Thereby, the movement of the flexible endoscope element inserted through the insertion portion 11 and the operation portion 12 becomes smooth. The material constituting the inner ring 52 is a synthetic resin having a smaller coefficient of friction than the metal outer ring 51. Specifically, tetrafluoroethylene resin, POM (polyacetal), PA (polyamide), polyolefin and the like are used.

  As the flexible endoscope element, a signal transmission cable 30, a light guide 31, an air supply channel 32, a water supply channel 33, and a treatment instrument insertion channel 34 are provided, but the flexible endoscope element is omitted in FIG. Thus, the flexible tube portion 39 is shown as a single unit, and in FIG. 4, the treatment instrument insertion channel 34 is shown as a representative example as the flexible endoscope element E.

The above electronic endoscope 10 is used as follows.
When the insertion part 11 of the electronic endoscope 10 is introduced into the body cavity of the patient, an observation area located in front of the objective lens provided on the distal end body of the insertion part 11 is converted into an electronic image by the CCD, and the image is obtained via the processor. It is displayed on the monitor device. While observing this projected endoscopic image, proceed with the observation inside the body cavity and bend as necessary so that the desired endoscopic image can be obtained or the inspection and treatment can be performed at the desired position The operation knobs 20A and 20B, the lock knob 21A and the lock lever 21B are operated to bend the bending portion 14 in the vertical and horizontal directions. As described above, in the insertion portion 11 and the operation portion 12 of the electronic endoscope 10, the signal transmission cable 30, the light guide 31, the air supply channel 32, the water supply channel 33, and the treatment instrument insertion channel 34 are flexibly viewed. A mirror element is inserted, and the flexible endoscope element moves forward and backward in the insertion portion 11 and the operation portion 12 in accordance with a bending operation of the bending portion 14. Specifically, when the bending portion 14 is bent, the flexible endoscope element is pulled toward the outside of the endoscope in conjunction with the bending state, and the bending portion 14 is restored from the bending state to the original linear shape. Then, the flexible endoscope element is pushed into the endoscope. Thus, the flexible endoscope element moves, but the contact between the enlarged connection ring 50 and the flexible endoscope element is only the cross-sectional arc surface 56 of the inner ring 52 made of a synthetic resin material. The friction generated between the diameter connecting ring 50 and the flexible endoscope element can be suppressed satisfactorily. Therefore, the load applied to the flexible endoscope element due to friction is reduced, and damage and failure of the flexible endoscope element can be prevented. At the same time, since the flexible endoscope element moves smoothly during the bending operation of the bending portion 14, the bending operability is improved.

  In the present embodiment, all the tapered holes 54 of the enlarged diameter connection ring 50 are formed in the inner ring 52, but at least a small diameter tapered hole part on the flexible tube 39 side is formed in the inner ring 52, and the operation part 12 side is provided. A large diameter tapered hole may be formed in the outer ring 51.

  FIG. 5 shows an endoscope in which a diameter-expanded connecting ring 50 ′ having a conventional structure is provided at the proximal end of the flexible tube 39. The enlarged diameter connection ring 50 ′ is made of metal and has a structure in which it is in full contact with the inner peripheral surface of the enlarged diameter connection ring 50 ′ in the middle from the flexible tube 39 to the internal space of the operation unit 12. . For this reason, when the flexible endoscope element tries to move forward and backward in the insertion portion and the operation portion in accordance with the bending operation of the bending portion, a load caused by friction with the enlarged-diameter connecting ring 50 ′ is applied to the flexible endoscope. It will be applied to the element and cause damage or failure of the flexible endoscope element. In particular, in a small-diameter endoscope in which a flexible tube portion such as a nasal endoscope has a very small diameter, the space occupied by the flexible endoscope element is small in the insertion portion and the operation portion, and the movable space Therefore, a load due to friction is more likely to be applied. On the other hand, according to the present embodiment, the contact between the enlarged connection ring 50 and the flexible endoscope element is only the cross-sectional arc surface 56 of the inner ring 52 made of a synthetic resin material. The load applied by friction is reduced, and damage and failure of the flexible endoscope element can be prevented.

1 is an overall view of an endoscope to which the present invention is applied. It is sectional drawing which shows the connection part of the flexible tube part and operation part of the endoscope. It is sectional drawing which showed the base end side (operation part side edge part) of the flexible tube which comprises a flexible tube part with the flexible tube single-piece | unit. It is sectional drawing which expands and shows the base end side of the flexible tube. It is an endoscope provided with the diameter expansion connection ring of the conventional structure, Comprising: It is sectional drawing which shows the connection part of a flexible tube part and an operation part.

Explanation of symbols

DESCRIPTION OF SYMBOLS 10 Electronic endoscope 11 Insertion part 12 Operation part 13 Tip part 14 Bending part 15 Flexible tube part 20A 20B Bending operation knob 21A Lock knob 21B Lock lever 22 Universal tube 23 Connector part 30 Signal transmission cable 31 Light guide 32 Air supply channel 33 Water supply channel 34 Treatment tool insertion channel 35 Remote operation button switch 36 Air supply / water supply button 37 Treatment tool insertion port projection 38 Suction button 39 Flexible tube 40 Flexible tube outer skin 41 Reticulated tube 42 Spiral tube 43 Inner tube 44 Bending rubber tube 50 Expanded Connection Ring 51 Outer Ring 52 Inner Ring 53 Screw 54 Tapered Hole 55 Reverse Tapered Hole 56 Cross Section Arc Surface E Flexible Endoscope Element (Built-in)

Claims (6)

A flexible insertion portion having a smaller diameter than the operation portion is provided at the distal end of the large-diameter operation portion, and a flexible tube is located in the insertion portion. , An enlarged connection ring having a tapered hole that expands toward the internal space of the operation portion is fixed,
In an endoscope in which a continuous flexible endoscope element is inserted into the operation portion inner space, the enlarged diameter connection ring and the flexible tube,
A metal outer ring that is fixed to the end of the flexible tube, and a synthetic resin inner ring that is located inside the metal outer ring and contacts the flexible endoscope element. Consisting of
An endoscope characterized in that a small-diameter tapered hole portion on at least the flexible tube side of the tapered hole is formed in the inner ring. The endoscope according to claim 1, wherein a large-diameter tapered hole portion on the operation portion side is formed in the metal outer ring among the tapered holes. 3. The endoscope according to claim 1, wherein the inner ring made of synthetic resin is screwed to the outer ring made of metal with a screw centered on the axis of the flexible tube. The endoscope according to any one of claims 1 to 3, wherein the inner ring made of synthetic resin is positioned on the flexible tube side from the small diameter tapered hole portion and has a diameter toward the flexible tube side. An endoscope in which a reverse taper hole for expanding the diameter is formed, and the small diameter taper hole portion and the reverse taper hole are connected by a smooth circular arc surface. The endoscope according to claim 4, wherein an inner diameter of the circular arc surface in cross section is equal to or larger than an inner diameter of the flexible tube. The endoscope according to any one of claims 1 to 5, wherein the synthetic resin constituting the inner ring of the expanded connection ring is a tetrafluoroethylene resin, polyacetal, polyamide, or polyolefin.

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