JPH0730003Y2 - Inward vision bending device - Google Patents

Description

[Detailed Description of the Invention] [Industrial field of application] The present invention relates to a bending device for an endoscope for arbitrarily bending a bending portion provided at a distal end of an insertion portion of the endoscope.

[Conventional technology]

The bending part of the endoscope has the maximum bending (maximum bending) depending on the direction.
There are quite a few cases where the angle is changed. For example, as shown in FIG. 5, the upper side is set to 210 degrees and the lower side is set to 90 degrees.

In FIG. 5, reference numeral 51 is a flexible tube forming an insertion portion of the endoscope. 52 is a curved portion connected to the tip of the flexible tube 51,
The tips of both the upper and lower operation wires 53a and 53b are attached to the tip portion of the bending portion 52. Also, guide coils 54a, 54b for guiding the operation wires 53a, 53b in the flexible tube 51.
Has its tip fixed near the connecting portion between the flexible tube 51 and the bending portion 52. A is the fixed portion.

[Problems to be solved by the device]

It is desirable that the curved portion 52 be bent at a portion as close to the tip as possible. However, since various built-in components such as forceps channels are fixed to the tip side, generally, the portion closer to the tip is less likely to bend.

Therefore, if all of the guide coils 54a and 54b are fixed near the connecting portion between the flexible tube 51 and the bending portion 52 as described above,
As shown in FIG. 5, when bent downward with a small maximum bending angle, the bending portion bends only at the base side, which impairs the guiding performance of the endoscope.

Therefore, for example, as shown in FIG. 6, it is possible to fix the tip of the lower guide coil 54b to the middle of the curved portion 52. By doing so, as shown in FIG. 7, when bent downward, only the tip end side of the bending portion 52 can be bent.

However, in this case, as shown in FIG. 8, when the upper guide is bent, the lower guide coil 54b is pulled, the resistance against operation is increased, and a sufficient bending angle cannot be obtained. There is a drawback that the durability of the operation wire and the optical fiber bundle inserted inside is impaired.

An object of the present invention is to provide a bending device for an endoscope which eliminates such conventional drawbacks and allows the distal end side portion of the bending portion to be smoothly and smoothly bent.

[Means for Solving the Problems]

In order to achieve the above-mentioned object, the bending device for an endoscope of the present invention is provided with a bendable bending portion at the tip of a flexible tube forming the insertion portion of the endoscope, and at the tip side of the bending portion. While attaching the tip of the operation wire, the operation wire is inserted into the flexible guide tube inserted into the flexible tube so that the operation wire can advance and retreat.
In a bending device for an endoscope in which the bending portion is bent by pulling the operation wire from the proximal end side, an intermediate portion of the guide tube is fixed near a connecting portion between the flexible tube and the bending portion. In addition, the tip end portion of the guide tube on the front side of the fixed portion is made to be a free end and protruded into the curved portion.

[Action]

Since the tip of the flexible guide tube protrudes from the flexible tube into the bending section, when the operation wire in the guide tube is pulled toward the base side, the bending section bends mainly at the tip side of the tip of the guide tube. To do.

When the other operation wire is pulled and the operation wire is on the loose side, the guide tube is not fixed in the bending portion, so that the guide tube is not pulled and an unreasonable force is not applied.

〔Example〕

 Embodiments will be described with reference to the drawings.

FIG. 2 shows the entire configuration of the endoscope. A bendable bending portion 2 is connected to a distal end portion of a flexible tube 1 forming an insertion portion, and an operation is performed on a proximal end side of the flexible tube 1. The parts 3 are connected.

The pair of operation wires 4a, 4b for bending in the vertical direction and the pair of operation wires 4c, 4d for bending in the left-right direction are respectively drawn from inside the bending portion 2 through the inside of the flexible tube 1 and into the operating portion 3. By rotating the vertical bending operation knob 6 and the left and right bending operation knob 7 protruding from the operation portion 3, the operation wires 4a, 4
The b, 4c, 4d are selectively pulled so that the bending portion 2 can be bent in a desired direction by a desired angle.

To the tip of the curved portion 2, a tip body 8 to which the tips of various built-in objects such as optical fiber bundles and forceps channels (not shown) are fixed is connected.

FIG. 1 schematically shows the configuration near the bending portion 2.

The curved portion 2 is provided with a large number of node rings 22,23,24,2 by rivets 21.
It is configured by connecting 5 rotatably. Then, the distal end main body 8 is connected to the distal end joint ring 22, and the proximal end joint ring 25
The flexible tube 1 is connected to the via a connecting ring 11. The tips of the operation wires 4a, 4b, 4c, 4d are fixed to the inner surface of the node ring 22 at the tips. 26 is an operation wire in the bending portion 2.
It is a wire guide projectingly provided on the inner surface of each node ring 23, 24 for guiding the traveling of 4a, 4b, 4c, 4d.

In the flexible tube 1, the operation wires 4a, 4b, 4c, 4d are inserted in flexible close-wound guide coils (guide tubes) 9a, 9b, 9c, 9d so as to be able to move back and forth. The guide coils 9a, 9b, 9c, 9d are inserted through the flexible tube 1, the base end side of which is fixed inside the operating portion 3, and the tip end side of which is fixed on the inner surface of the connecting ring 11. Part B is the fixed part.

However, only the lower guide coil 9b is fixed to the connecting ring 11 in the middle of the coil, and the front side from the fixed portion B is a free end that is not fixed anywhere and is projected halfway inside the bending portion 2. There is. Then, a slight gap (for example, about 1 mm) t is formed between the tip end surface of the guide coil 9b and the wire guide 26. Other guide coils 9a, 9c, 9d
Has a tip portion fixed to the connecting ring 11.

In FIG. 1, the front half (right side in the drawing) of the bending portion 2 is schematically shown, and a rubber tube or the like that covers the bending portion 2 is not shown.

FIG. 3 schematically shows a state in which the lower operation wire 4b is pulled from the operation section 3 side. The maximum downward bending angle is 180 degrees, for example.

At this time, the base portion side (E portion) of the bending portion 2 where the lower guide coil 9b projects is bent to a position where the gap t between the guide coil 9b and the wire guide 26 becomes zero. Therefore, if t is set to zero from the beginning, E
The portion does not bend at all, and if t is set to a large value, the E portion bends greatly. In this embodiment, t is a slight gap of about 1 mm, so the E portion is slightly bent.

On the other hand, since the E part hardly bends, the guide coil
The part (F part) on the tip side of the tip of 9b is largely bent.
Therefore, as the entire curved portion 2, a smooth curved shape in which the base side (E portion) is slightly bent and the tip side (F portion) is greatly bent is obtained.

FIG. 4 schematically shows a state in which the upper operation wire 4a is pulled from the operation portion 3 side. The maximum bending angle in the upward direction is 210 degrees, for example.

At this time, the bending portion 2 is located at the base side (E
Portion), and then the tip side (F portion) bends and bends at a large angle as a whole. At this time, the lower guide coil 9b is located on the outer peripheral side of the bending portion 2, but is not fixed inside the bending portion 2, so that the gap t with the wire guide 26 simply increases, and it is impossible anywhere. No force is applied.

Although the tip of the guide coil in the flexible tube 1 is extended and protruded into the bending portion 2 in the above-described embodiment, the present invention is not limited to this, and the inside of the flexible tube 1 is curved. It is also possible to use a coil different from that in the portion 2 on the parts and connect them in the vicinity of the fixing portion B.

Further, the guide coil that projects into the bending portion 2 is not limited to one, and a plurality or all of the guide coils may project into the bending portion 2. Then, the protruding length into the bending portion 2 may be changed depending on the bending angle or the like.

[Effect of device]

According to the bending device for an endoscope of the present invention, even if the maximum bending angle of the bending portion varies depending on the direction, the free end of the flexible guide tube is projected into the bending portion from the flexible tube side. By flexibly bending the tip end side portion of the bending portion in any direction, it is possible to obtain excellent guiding performance in a body cavity or the like.

[Brief description of drawings]

FIG. 1 is a schematic side sectional view of a bending device for an endoscope of an embodiment, FIG. 2 is an overall external view of an endoscope of the embodiment, and FIGS. 3 and 4 are drawings of the inside of the embodiment. FIG. 5 is a schematic side sectional view of a bending device of an endoscope when bent, and FIGS. 5 to 8 are schematic side views of a bending device of a conventional endoscope. DESCRIPTION OF SYMBOLS 1 ... Flexible tube, 2 ... Bending part, 4b ... Operation wire, 9b ... Guide coil (guide tube).

Claims (1)

[Scope of utility model registration request] 1. A flexible tube forming an insertion section of an endoscope is provided with a bendable bending section at its distal end, and a distal end of an operation wire is attached to the distal end side of the bending section and inserted into the flexible tube. In the bending apparatus for an endoscope, the operation wire is inserted into the flexible guide tube so as to be able to move back and forth, and the operation wire is pulled from the proximal end side to bend the bending portion. The guide tube is fixed midway near the connecting portion between the tube and the bending portion, and the tip end portion of the guide tube ahead of the fixing portion is made to be a free end and projected into the bending portion. Bending device for endoscopes.