JP2008237843A - Endoscope - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide an endoscope in which an insertion tube has difference in hardness in the axial direction without adding any special member to a coil sleeve as a guide member of an operation wire. <P>SOLUTION: The operation wire 12 for operating to bend a bending section 3b is inserted into the coil sleeve 14 within a soft part 3a. Both ends of the coil sleeve 14 are respectively connected with attachment pipes 15a, 15b. The attachment pipe 15a is fixed within a body control section 2 and the other attachment pipe 15b to a migration part between the soft part 3a and the bending section 3b. The diameter D of the coil sleeve 14 is small, that is D1, at a small-diameter coil part 14a at the rear end side and is large, that is D2, at a large-diameter coil part 14b at the distal end part. The small-diameter coil part 14a is harder in the bending direction and harder to bend compared to the large-coil diameter part 14b. <P>COPYRIGHT: (C)2009,JPO&INPIT

Description

  The present invention relates to an endoscope having an insertion portion in which a connection side from a predetermined position to a main body operation portion is harder to bend than a distal end side, such as a colonoscope.

  In an endoscope having an insertion portion in which a bending portion is provided at the distal end of a flexible portion and a distal end hard portion provided with an endoscope observation means or the like is provided at the distal end of the bending portion, for example, a colonoscope is inserted into a body cavity. The resistance to insertion into the insertion path is large, and it is inserted into a complicated curved path. Therefore, in order to reliably transmit the pushing force to the insertion portion to the tip, and to smoothly advance along the insertion path that is bent in a complicated manner, In order to transmit the pushing force effectively, the part on the connecting part side should be hard and hard to bend, and the tip side should be flexible in the bending direction so that it can proceed smoothly along the curved path. It is configured to be high.

  As described above, various attempts have been made in the past to make the flexible portion of the insertion portion of the endoscope have a difference in hardness in the length direction, and it has been put into practical use. Here, the tubular member as the structure part of the soft part in the insertion part is generally composed of a spiral tube in which a metal strip is spirally wound, and this spiral tube has a double structure by changing the winding direction. . The spiral tube is covered with a metal net, and the outermost layer is covered with a resin layer. Therefore, by changing the degree of flexibility in the bending direction in the axial direction of any of these constituent members, the connecting side to the main body operation unit is hardened and the distal end side is easily bent.

For example, in Patent Document 1, the resin layer in the soft part is composed of a mixture of a soft elastomer and a hard elastomer, and the distal end side of the insertion part has a high content ratio of the soft elastomer and the rear part has a higher content ratio of the hard elastomer. What has been made is disclosed. In addition, not only the tubular member of the insertion part has a difference in hardness in the axial direction but also a structure in which the hardness is changed by a member built in the insertion part is known. For example, in patent document 2, it is set as the structure which gives the difference of the hardness of a bending direction to the axial direction of the guide member which penetrated the operation wire for bending the bending part of an insertion part by remote control. Generally, an operation wire for bending operation is inserted into a closely wound coil. However, in the configuration of Patent Document 2, another closely wound coil or the like is provided between the densely wound coil and a predetermined length from the main body operation unit side. It is made to pass through a metal pipe made of
Japanese Patent Laid-Open No. 2-131738 Japanese Patent Laid-Open No. 10-127469

  However, in the configuration of Patent Document 1, a special molding machine must be used, which not only makes molding of the resin layer difficult, but also causes deterioration of the resin layer due to cleaning and disinfection performed each time an endoscope is used. Considering that the hardness changes, there is a problem that stable characteristics cannot be provided for a long period of time. Further, as described in Patent Document 2, in addition to the guide means for the operation wire, if only a tightly wound coil is provided in order to give the insertion portion a difference in hardness, the number of parts will increase. There is a problem that the assembly is troublesome.

  The present invention has been made in view of the above points, and its object is to provide hardness in the axial direction of the insertion portion without adding a special member to the coil sleeve as the guide member of the operation wire. There is a difference between them.

  In order to achieve the above-described object, the present invention provides an insertion unit connected to a main body operation unit, and the insertion unit is formed as a distal end hard portion, a bending portion, and a soft portion in order from the front end side. At least one operation wire is attached to be bent by the operation wire, and the operation wire is inserted into the coil sleeve in the main body operation portion from the inside of the soft portion, and the coil sleeve Is composed of a spirally wound metal wire, and changes the winding state from the middle position in the axial direction, the change in the winding state of the coil sleeve, the rear side, It is characterized in that it is set so that the resistance to bending is larger than the tip side.

  Even when the coil sleeve is wound in a coil shape using a metal wire having the same wire diameter, the hardness in the bending direction changes depending on the winding method, for example, the size of the coil diameter. Further, the hardness in the bending direction varies depending on whether the winding is performed densely or roughly. Therefore, when the coil sleeve is formed, a difference in hardness in the axial direction is generated by changing the winding method of the coil shape, that is, by changing the winding state. If the coil diameter is reduced, that is, if it is a small-diameter coil part, the degree of hardness in the bending direction becomes larger than that of a large-diameter coil part having a large coil diameter. Further, the resistance in the bending direction is greater in the densely wound coil portion in which the coil sleeve is densely wound than in the coarsely wound coil portion in which the coil sleeve is roughly wound. Therefore, in the axial direction of the coil sleeve, the coil diameter is changed, or the winding state is changed such that the coil is partially wound with a change in density, or the change in density and the coil diameter are changed. By combining the change, a difference in hardness can be generated in the axial direction of the insertion portion. In the case of providing a difference in density between the coil pitches, the difference in hardness becomes larger when the coil sleeve is assembled in a compressed state in the insertion portion.

  The bending portion in the insertion portion includes, for example, only one direction in the up direction, which can be bent in two directions in the up and down direction, and further one in which the bending operation can be performed in four directions in the up, down, left and right directions. Accordingly, the number of operation wires attached is one, two, four, and the like according to the possible bending operation directions, and naturally the same number of coil sleeves are provided. The change portions of the winding state of each of the coil sleeves can all be at the same position, or the change positions of the winding state can be shifted.

  By configuring as described above, the hardness of the insertion portion can be changed without adding any member.

    Hereinafter, embodiments of the present invention will be described with reference to the drawings. First, FIG. 1 shows the overall configuration of the endoscope. The endoscope 1 is provided with an insertion unit 3 connected to a main body operation unit 2 and a universal cord 4 that is detachably connected from the main body operation unit 2 to a light source device or the like. The insertion portion 3 is inserted into the body of the subject, and becomes a flexible portion 3a that bends in an arbitrary direction along the insertion path for a predetermined length from the connection portion to the main body operation portion 2. The bending portion 3b is provided at the distal end of the soft portion 3a, and the distal end hard portion 3c is connected to the bending portion 3b.

  The bending portion 3b in the insertion portion 3 is configured to be bendable by remote operation, and a bending operation means 5 is attached to the main body operation portion 2 in order to perform this bending operation. In the illustrated endoscope 1, the bending portion 3b is configured to be able to bend in four directions, up and down and left and right. Thus, by providing the curved portion 3b, the distal end hard portion 3c fitted with the endoscope observation means can be directed in a desired direction, and the distal end hard portion 3c can be guided in a predetermined insertion direction. Moreover, the direction of the observation visual field of the endoscope observation means can be changed.

  FIG. 2 shows a schematic configuration of a bending operation mechanism for bending the bending portion 3b in two directions, for example, in the vertical direction. In addition, in order to perform the bending operation in the four directions of up and down and left and right, another same bending operation mechanism is provided.

  In the figure, reference numeral 10 denotes a pulley provided in the main body operation unit 2 and rotationally driven by a shaft 11, and the shaft 11 is provided in connection with the bending operation means 5. A pair of operation wires 12 and 12 are wound around the pulley 10. Both operation wires 12 extend into the insertion portion 3, and their distal ends are fixed to a distal end ring 13 of the curved rings constituting the curved portion 3 b.

  The operation wire 12 is inserted through the coil sleeve 14 in the soft part 3a. At a predetermined position in the main body operation unit 2, the rear end portion of the coil sleeve 14 is connected to the attachment pipe 15 a, and the attachment pipe 15 a is fixed at a predetermined position in the main body operation unit 2. On the other hand, as shown in FIG. 3, the distal end portion of the coil sleeve 14 extends to the transition portion between the flexible portion 3 a and the bending portion 3 b in the insertion portion 3. The flexible portion 3 a and the curved portion 3 b are connected by a connecting ring 16, and the attachment pipe 15 b is fixed to the connecting ring 16.

  The operation wire 12 is further led out from the attachment pipe 15b. In the bending portion 3b, the operation wire 12 is positioned so as to be held at a predetermined position in the circumferential direction of the distal end ring 13 constituting the bending portion 3b. It extends to a position and is fixed to the tip ring 13. Therefore, when four operation wires 12 are provided, each of the operation wires 12 is extended to the tip ring 13 while maintaining a positional relationship of 90 degrees, and is fixed to the tip ring 13.

  The coil sleeve 14 is formed by spirally winding a metal wire, and the operation wire 12 is inserted through the coil sleeve 14. The coil sleeve 14 is formed in a tightly wound coil shape, and an operation wire 12 inserted inside can be pushed and pulled. Therefore, the inner diameter of the coil sleeve 14 is larger than the outer diameter of the operation wire 12, and the operation wire 12 can slide smoothly inside the coil sleeve 14. As shown in FIG. 4, the coil sleeve 14 is not constant in coil diameter, and has a small-diameter coil portion 14 a in which the diameter D <b> 1 is reduced on one end side, and the diameter gradually increases in the middle portion. Thus, the other end portion is a large diameter coil portion 14b having a large diameter D2. Although it depends on the diameter difference between the diameters D1 and D2, the transition portion 14c between the small diameter coil portion 14a and the large diameter coil portion 14b is several turns or more.

  Here, when the coil sleeve 14 is made of the same material and has the same wire diameter, it becomes difficult to bend when the coil diameter is reduced, and it is easy to bend when the coil diameter is increased. That is, by changing the coil diameter, that is, the winding state with a single coil sleeve 14, the small diameter coil portion 14a having the coil diameter of the diameter D1 is larger than the large diameter coil portion 14b having the coil diameter of the diameter D2. It becomes harder and more difficult to bend in the bending direction. And the difference in hardness becomes large, so that the diameter difference of diameter D1 and D2 becomes large. The transition portion 14c between the small-diameter coil portion 14a and the large-diameter coil portion 14b may be about two or three turns, but the hardness in the bending direction changes suddenly and a part of the coil is forcibly deformed. If so, the length of the transition portion 14c can be lengthened to some extent, for example, about 7 or 8 turns.

  The small-diameter coil portion 14a has a predetermined length from the rear side, that is, the connecting portion to the mounting pipe 15a, and the large-diameter coil portion 14b is the front end side, that is, the connecting portion side to the mounting pipe 15b. As a result, in the insertion portion 3, the flexible portion 3 a has a rear end side, that is, a connection side to the main body operation portion 2 stiffened in a bending direction, and a distal end side is easily bent. Therefore, by appropriately setting the position of the transition portion 14c of the coil sleeve 14 in the soft portion 3a, the pushing force can be reliably transmitted to the distal end hard portion 3c when inserted into the body cavity of the insertion portion 3, and It bends smoothly following the bending of the insertion path.

  In order to make the bending portion 3b bendable in four directions, up and down and left and right, when four operation wires 12 inserted through the coil sleeve 14 are provided, the positions of the transition portions of the coil sleeves 14 are the same position. It is also possible to change the position of the transition portion 14c in each coil sleeve 14 in the axial direction. As a result, the hardness of the soft part 3a changes stepwise or almost continuously from a predetermined position on the connection side to the main body operation part 2 toward the connection part to the bending part 3b. Therefore, the insertion operability is further improved.

  Here, in order to give a difference in hardness in the bending direction in the axial direction of the coil sleeve, as described above, not only the coil diameter is changed in the axial direction of the coil sleeve 14, but also as shown in FIG. Further, a difference in hardness in the bending direction can also be provided by changing the coil winding pitch. That is, one end side of the coil sleeve 114 is a densely wound coil portion 114a wound so that the pitch is in close contact, and the other end side is a coarsely wound coil portion 114b having a large pitch interval. Have a difference. This increases the hardness of the densely wound coil portion 114a compared to the coarsely wound coil portion 114b.

  Although the coil sleeve 114 is connected between the attachment pipes 115a and 115b, the entire length of the coil sleeve 114 can be made longer than the distance between the attachment pipes 115a and 115b in the insertion portion 3. Therefore, the coil sleeve 114 is mounted in a compressed state. Here, the degree of compression of the coarsely wound coil portion 114b is larger than that of the densely wound coil portion 114a, and the elastic winding is more greatly deformed. However, the tightly wound coil portion 114a increases the degree of close contact between the coils. As a result, the tightly wound coil portion 114a is harder than the coarsely wound coil portion 114b when the coil sleeve 114 is attached in a compressed state rather than the coil sleeve 114 attached without being compressed or stretched. The difference in thickness becomes more prominent.

  Therefore, the end of the coil sleeve 114 on the side of the densely wound coil portion 114a is connected to the attachment pipe 115a on the rear end side, and the end on the side of the coarsely wound coil portion 114b is connected to the attachment pipe 115b. It is possible to provide a difference in hardness in the axial direction of the coil sleeve 114 located at the position. Of course, also in this case, it is desirable to provide a transition portion 114c in which the winding pitch interval is changed between the densely wound coil portion 114a and the coarsely wound coil portion 114b.

  As described above, the hardness in the length direction of the flexible portion 3a of the insertion portion 3 can be changed by simply changing the winding state of the coil sleeve and without adding any member. The configuration for providing the difference is greatly simplified. Here, the intended purpose can be achieved by any configuration in which the coil diameter of the coil sleeve is changed or the coil pitch is changed. Moreover, you may make it change both a coil diameter and a coil pitch.

1 is an overall configuration diagram of a general endoscope. FIG. It is a schematic block diagram of the bending operation mechanism for bending the bending part of an insertion part by remote control. It is sectional drawing which shows the connection part of the soft part and bending part in an insertion part. It is sectional drawing of the coil sleeve which shows the 1st Embodiment of this invention. It is sectional drawing of the coil sleeve which shows the 2nd Embodiment of this invention.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Endoscope 2 Main body operation part 3 Insertion part 3a Soft part 3b Curved part 3c Hard tip hard part 14,114 Coil sleeve 14a Small diameter coil part 14b Large diameter coil part 14c Transition part 15a, 15b, 115a, 115b Attachment pipe 114a Close winding Coil part 114b Coarse winding coil part

Claims (3)

An insertion part is connected to the main body operation part, and this insertion part is made into a hard tip part, a bending part and a soft part in order from the tip side, and at least one operation wire is connected to bend by an operation from the main body operation part. In an endoscope that is configured to be inserted into a coil sleeve in the main body operation part from the inside of the flexible part,
The coil sleeve is configured by spirally winding a metal wire, so that the winding state is changed from the middle position in the axial direction,
The endoscope is characterized in that the change in the winding state of the coil sleeve is set so that the rear side is more resistant to bending than the tip side. By increasing at least one of the winding diameter on the front end side of the coil sleeve or rough winding, and the winding diameter on the rear end side is reduced or dense winding, the rear side is the The endoscope according to claim 1, wherein resistance to bending is greater than that at a distal end side. In order to enable the bending portion to be bent in four directions, four operation wires inserted through the coil sleeve are provided, and the change position of the winding state of each of the coil sleeves is the axis of the insertion portion. The endoscope according to claim 1, wherein the endoscope is configured to have different positions in the direction.

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