JP2005230135A - Flexible tube for endoscope - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a flexible tube for an endoscope, which has the most suitable flexibility to insert into a human body with a structure of a superelastic alloy pipe covered only by a shell. <P>SOLUTION: The flexible tube of the endoscope is so constituted that the shell 12 is applied on the superelastic alloy pipe 11 to surround a circumferential surface thereof, wherein a plurality of long and narrow peripheral slits 13 and 13' are formed in the superelastic alloy pipe at intervals in an axial direction and the peripheral slits 13 and 13' are made to exist at a plurality positions with intervals on a section which is perpendicular to the axis of the superelastic pipe 11. <P>COPYRIGHT: (C)2005,JPO&NCIPI

Description

  The present invention relates to a flexible tube of an endoscope.

In general, the flexible tube of an endoscope has a configuration in which a metal tube is coated on the outer periphery of a metal tube, and the outer periphery of the tube is further coated with a sheath made of a flexible tube or the like. However, since it is difficult to adopt such a configuration in the case of an extremely thin endoscope or the like, a configuration in which the outer peripheral surface of the superelastic alloy pipe is covered with an outer skin is employed (Patent Document 1).
JP-A-11-332822

  However, with the configuration in which the superelastic alloy pipe is simply covered with the outer skin as described above, the thickness of the superelastic alloy pipe is thin enough to the extent that the strength is not hindered, so that the flexibility is insufficient, and it is somewhat hard. The insertability was not good because it became a characteristic.

  In addition, the flexible tube of the endoscope is made flexible so that the distal part bends well along the shape of the organ in the body, and the part near the hand does not meander significantly during the pushing operation. It is preferable to give a hardness of a certain level or more, but such a characteristic cannot be obtained only by covering the superelastic alloy pipe with the outer skin, resulting in poor insertion.

  Accordingly, an object of the present invention is to provide a flexible tube for an endoscope that can obtain optimum flexibility for insertion into a human body even when the superelastic alloy pipe is simply covered with a skin. .

  In order to achieve the above object, an endoscope flexible tube according to the present invention is an endoscope flexible tube having a structure in which an outer skin is covered so as to surround an outer peripheral surface of a superelastic alloy pipe. The pipe is formed with a plurality of elongated circumferential slits spaced apart in the axial direction.

  The circumferential slits may be formed at a plurality of positions at intervals on a cross section perpendicular to the axis of the superelastic alloy pipe. In this case, the first cross section perpendicular to the axis of the superelastic alloy pipe , Two circumferential slits are formed at 180 ° symmetrical positions, and in the second cross section shifted in the axial direction from the first cross section, 90 ° with respect to the circumferential slit of the first cross section. Two circumferential slits may be formed at positions 180 ° symmetrical with the phase changed, and the first cross section and the second cross section may be alternately arranged.

  In addition, the flexible tube of an endoscope having excellent strength when the circumferential slit of the first cross section and the circumferential slit of the second cross section are formed so as not to overlap when viewed from the axial direction. Can be configured.

  Further, by making the circumferential length of the circumferential slit different depending on the direction in which the circumferential slit is located, the flexibility may be different depending on the direction. The flexibility may be changed in the middle by changing at least one of the arrangement intervals in the axial direction.

  According to the present invention, the superelastic alloy pipe is formed with a plurality of elongated circumferential slits at intervals in the axial direction. Optimum flexibility for insertion can be obtained.

  In a flexible tube of an endoscope having a structure in which an outer skin is covered so as to surround an outer peripheral surface of a superelastic alloy pipe, a plurality of elongated circumferential slits are formed in the superelastic alloy pipe at intervals in the axial direction. .

Embodiments of the present invention will be described with reference to the drawings.
FIG. 3 shows the overall configuration of the endoscope. The bending portion 2 is formed at the distal end portion of the flexible insertion portion 1, and the distal end portion body 3 on which the observation window 4 and the like are arranged is the bending portion 2. Connected to the tip. A bending operation knob 6 or the like for bending the bending portion 2 is disposed on the operation portion 5 connected to the base end of the insertion portion 1.

  FIG. 1 shows a flexible tube that covers the insertion portion 1, and illustration of optical fiber bundles and tubes that are inserted and disposed therein is omitted. In the case of an electronic endoscope, an imaging signal transmission cable and the like are also inserted and arranged.

  The flexible tube of the endoscope is closely attached to the outer peripheral surface of, for example, a Ti-Ni superelastic alloy pipe 11 having shape memory characteristics, by an outer skin 12 made of a flexible tube such as polyethylene or polyurethane. It is configured by covering. As the outer skin 12, a heat shrinkable tube may be used, or a synthetic resin may be directly extruded on the outer surface of the superelastic alloy pipe 11.

  The superelastic alloy pipe 11 is formed with a plurality of elongated circumferential slits 13 and 13 ′ spaced apart in the axial direction. In this embodiment, it is also shown in FIG. 2 illustrating a II-II cross section. Thus, in the first cross section perpendicular to the axis of the superelastic alloy pipe 11, the two circumferential slits 13 are formed at intervals of 180 ° at intervals.

  Then, in the second cross section whose position is shifted in the axial direction from the first cross section (II-II cross section), the position is symmetrical by 180 ° by changing the phase by 90 ° with respect to the circumferential slit 13 of the first cross section. Two circumferential slits 13 'are formed at intervals, and the first and second cross sections in which such circumferential slits 13 and 13' are formed are alternately arranged.

  Therefore, by appropriately selecting the circumferential length of the circumferential slit 13 and the arrangement interval in the axial direction, the flexibility of the flexible tube of the endoscope is set to the hardness most suitable for the insertion property of the endoscope. It can be set arbitrarily.

  As in this embodiment, the circumferential lengths of the circumferential slit 13 of the first cross section and the circumferential slit 13 'of the second cross section are both formed to be less than 90 ° and viewed from the direction parallel to the axis. In some cases, the circumferential slit 13 of the first cross section and the circumferential slit 13 ′ of the second cross section are configured not to overlap each other, so that the mechanical strength is significantly superior to the case where there are overlapping portions. Can be secured.

  Further, as in the example shown in FIG. 4, the circumferential lengths of the circumferential slit 13 of the first cross section and the circumferential slit 13 ′ of the second cross section are made different, for example, in the vertical direction flexibility. It is possible to make the flexibility different depending on the direction around the axis line, for example, by making it larger than the flexibility in the left-right direction.

  Further, as in the example shown in FIG. 5, by changing both or one of the circumferential lengths of the circumferential slits 13 and 13 ′ and the arrangement interval in the axial direction in the middle, flexibility can be achieved in the middle of the longitudinal direction. For example, the flexibility of the portion 1A near the distal end of the insertion portion 1 can be made larger than the flexibility of the portion 1B near the hand.

  It should be noted that the present invention can be applied not only to the flexible tube of an extremely thin endoscope but also to the flexible tube of an endoscope having a general diameter larger than the ultrafine diameter. Moreover, you may apply to the connection flexible tube which connects the operation part 5 and the connector part which is not shown in figure.

It is side surface sectional drawing of the flexible tube of the endoscope of 1st Example of this invention. It is front sectional drawing (II-II sectional drawing in FIG. 1) of the flexible tube of the endoscope of 1st Example of this invention. 1 is a side view showing an overall configuration of an endoscope to which the present invention is applied. It is front sectional drawing of the flexible tube of the endoscope of the 2nd Example of this invention. It is side surface sectional drawing of the flexible tube of the endoscope of the 3rd Example of this invention.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Insertion part 11 Superelastic alloy pipe 12 Outer skin 13, 13 'Circumferential slit

Claims (6)

In the flexible tube of the endoscope having a structure in which the outer skin is covered around the outer peripheral surface of the superelastic alloy pipe,
A flexible tube for an endoscope, wherein a plurality of elongated circumferential slits are formed in the superelastic alloy pipe at intervals in the axial direction. The endoscope flexible tube according to claim 1, wherein the circumferential slits are formed at a plurality of positions at intervals on a cross section perpendicular to the axis of the superelastic alloy pipe. In the first cross section perpendicular to the axis of the superelastic alloy pipe, two circumferential slits are formed at positions symmetrical to 180 °, and in the second cross section shifted in the axial direction from the first cross section. The two circumferential slits are formed at 180 ° symmetrical positions by changing the phase by 90 ° with respect to the circumferential slit of the first cross section, and the first cross section and the second cross section are alternately formed. The flexible tube of an endoscope according to claim 2, wherein the flexible tube is disposed. The endoscope according to claim 1, 2 or 3, wherein the circumferential slit of the first cross section and the circumferential slit of the second cross section are formed in a positional relationship that does not overlap when viewed from the axial direction. Flexible tube. The endoscope according to claim 1, 2, 3 or 4, wherein the circumferential length of the circumferential slit is made different depending on the direction in which the circumferential slit is located, whereby the flexibility is different depending on the direction. Flexible tube. The endoscope according to claim 1, 2, 3, 4, or 5, wherein flexibility is changed in the middle by changing at least one of a circumferential length of each of the circumferential slits and an arrangement interval in the axial direction. Flexible tube.

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