JPH0673516B2 - Endoscope - Google Patents

Description

Description: TECHNICAL FIELD OF THE INVENTION The present invention relates to an endoscope having an improved structure for bending a bending tube portion formed in an insertion portion.

[Technical Background of the Invention and Problems Thereof] In general, an endoscope includes an operating section and an insertion section connected to the operating section. The insertion section includes a flexible tube section, a bending tube section connected to the tip of the flexible tube section, and a tip forming section connected to the tip of the bending tube section. The bending tube portion constitutes a bending core member by connecting a large number of tubular bodies rotatably in the vertical and horizontal directions. The bending tube portion can be remotely bent in the up, down, left, and right directions by an operation on the operation portion.

Conventionally, the means for remotely bending the bending tube portion has been performed by pushing and pulling an operation wire which is interlocked with an operation by an operation knob provided in the operation portion. That is, while the operation wire is slidably inserted over the entire length of the insertion portion, the distal end of the operation wire is connected to the tubular body located at the tip of the bending tube portion, and the rear end of the operation wire is connected to the operation knob. It was connected to, for example, a chain that is driven by rotation.

Then, the operation wire is pushed and pulled by rotating the operation knob, whereby the bending tube portion is bent in the vertical and horizontal directions.

However, in such a conventional structure, when the insertion portion is bent by being inserted into the body cavity of the patient, the operation wire is also bent accordingly. Then, the operation wire located inside the curved insertion portion is slackened, and the operation wire located outside is bent.

Even when the operation knob is rotated in such a state, the operation wire in the loosened or pulled state does not smoothly follow the operation operation of the operation knob. For this reason,
There is a problem that the bending operation of the bending tube portion cannot be reliably performed.

In addition, since the operation wire slidably inserted over the entire length of the insertion portion greatly increases the sliding friction resistance when the insertion portion is in a curved state, it is necessary to rotate the operation knob. The required operating force becomes large. For this reason, the operator may have difficulty in operating and may be tired early.

Furthermore, since the operation wire must be slidably provided over the entire length of the insertion portion, the operation portion must be provided with an operation knob, and an operation mechanism for pushing and pulling the operation wire interlocking with the operation knob must be provided. These structures have a drawback that they are extremely complicated and the weight is increased.

On the other hand, in Japanese Patent Laid-Open No. 58-25140, a shape memory alloy member is arranged between each tubular body (joint piece) that constitutes a bending core material of a bending tube portion, and each shape memory alloy member is energized. Then, the one that is bent and driven by being heated is proposed.

However, in this type, since a shape memory alloy member is arranged between each of a large number of tubular bodies (joint pieces) that form the bending core material of the bending tube portion, the structure is complicated. Become. Also, the wiring structure for energizing each shape memory alloy member becomes complicated.

Further, since the shape memory alloy member is arranged between each of the plurality of tubular bodies (joint pieces), the length of each shape memory alloy member is shortened and the electric resistance of the shape memory alloy member is reduced. There is an inconvenience that the energization amount for heating the shape memory alloy member has to be increased. Moreover, the shrinkage ratio of the entire shape memory alloy member with respect to the entire length of the bending tube portion tends to be small.

[Object of the Invention] The present invention has been made in view of the above problems, and an object thereof is to easily and surely perform a bending operation of a bending tube portion regardless of a bending state of an insertion portion. An object of the present invention is to provide an endoscope which is capable of simplifying the structure, enables the insertion portion to have a small diameter, and can perform a sufficient bending operation with a small amount of electricity.

[Summary of the Invention] An endoscope of the present invention includes a bending tube portion formed by connecting a plurality of electrically conductive tubular bodies provided in an insertion portion, and a shape memory alloy installed between both ends of the bending tube portion. And a bending drive member that shortens its length by being energized and heated, and one end of the bending drive member is electrically connected to the distal end side of the bending tube portion, and the bending drive member is bent to the rear end side. By electrically connecting a lead wire to the other end of the driving member and energizing and heating the bending driving member by energization, the bending driving member made of a shape memory alloy is energized through the bending tube portion to adjust its length. The length is shortened so that the bending tube portion is bent.

[Embodiment of the Invention] A first embodiment of the present invention will be described with reference to Figs.

The endoscope shown in FIG. 1 has an operation section 1 and an insertion section 2 whose proximal end side is connected to the operation section 1. The insertion part 2
The tip forming portion 5 is connected to the tip of the flexible tube portion 3 via the bending tube portion 4. The operation part 1 includes an air supply / water supply operation button 6, a suction operation button 7, an eyepiece part 8, and first to fourth switches 9, 10 for bending the bending tube part 4 vertically and horizontally. 11 and 12 are provided. Further, a light guide cable 14 having a connector 13 to be connected to a light source device (not shown) is connected to the operation portion 1 at the extended tip.

As shown in FIG. 2, the bending tube portion 4 is configured so that a large number of cylindrical tubular bodies 15 each having a short length can be alternately turned in the vertical direction indicated by the arrow a and the horizontal direction indicated by the arrow b. To form a bending core material. That is, in each tubular body 15, the pair of connecting pieces 16 are displaced from the respective end surfaces in the circumferential direction by 180 degrees, and the pair of connecting pieces 16 on the front and rear end surfaces thereof are displaced by 90 degrees in the circumferential direction from the other end side. Is projected. The pair of connecting pieces 16 adjacent to each other in the adjacent tubular bodies 15 are pivotally attached by the support shafts 17, respectively.
In addition, each of the tubular bodies 15 at the most distal end and the rearmost end of the bending tube portion 4 has a connecting piece 16 protruding from only one end surface.

Therefore, the curved tubular portion 4 to which the tubular body 15 is connected is bendable in the vertical direction indicated by the arrow a and the horizontal direction indicated by the arrow b orthogonal to the vertical direction as described above. .

In addition, on the outer peripheral surface of the tubular body 15 at the most distal end and the rearmost end, there is a 90 degree offset to a portion in the circumferential direction corresponding to the bending direction of the bending tube portion 4.
Pins 18 project from the respective places. The ends of a bending drive coil member 19, which will be described later, are connected to and connected to the pair of four pairs of pins 18 corresponding to the most distal end and the rearmost end.

The bending drive coil member 19 is formed by bending a wire made of a bidirectional shape memory alloy into a coil shape. When heated to a temperature higher than the transformation temperature, the entire length is reduced, and the coil member 19 is cooled to the transformation temperature or lower. And it has come to return to the original length. The transformation temperature is set higher than the body temperature of the human body. The surface of the coil member 19 or the tubular body 15 is electrically insulated even if there is a member that comes into contact with the coil member 19 or the tubular body 15 by, for example, applying an insulating coating.

In addition, each coil member 19 has a tubular body 15 whose tip is the most advanced.
On the other hand, for example, it is electrically connected via a pin 18, and one end of a first lead wire 20 is electrically connected to the rear end of each coil member 19. The other ends of the four first lead wires 20 are guided to the light guide cable 14 through the insertion portion 2 and the first to fourth switches 9, 10, 11, 12 provided on the operation portion 1. The light guide cable 14 is connected to a connector 13 provided at the end.

Further, one end of the second lead wire 21 is connected to the tubular body 15 at the rearmost end. The ends of the four coil members 19 are electrically connected to each other through the tubular bodies 15. This second
The other end of the lead wire 21 is connected to the connector 13 through the insertion portion 2 and the light guide cable 14. Then, if this connector 13 is connected to a light source device (not shown),
The lead wires 20 and 21 are connected to a power source in the light source device 12. In this state, the first to fourth switches 9, 10, 11, 12 of the operation unit 1 are selectively turned on.
By doing so, a DC voltage is applied to the bending drive coil member 19 connected to the switches 9, 10, 11, and 12, and the coil members 19 are heated to a transformation temperature or higher.

According to the bending tube portion 4 of the endoscope configured as described above, the first switch 9 is turned on and is located on the upper side in the vertical bending direction shown by the arrow a connected to the first switch 9. When the coil member 19 is energized and heated above the transformation temperature, the coil member 19 changes in shape and the coil length is reduced. Therefore, the tubular body 15 on the distal end side has the driving member 19
Since it is pulled upward by the bending tube portion 4, the bending tube portion 4 bends upward. At this time, the coil member 19 provided on the lower side in the direction of the arrow a elastically extends according to the bending of the bending tube portion 4, and does not prevent the bending of the bending tube portion 4. When the bending tube portion 4 is bent downward, the second
The switch 10 is turned ON to energize the coil member 19 located on the lower side in the arrow a direction, and when the coil member 19 is further bent in the left-right direction indicated by the arrow b, the third switch 11 or
If the switch 12 is turned ON and the left and right coil members 19 are energized and heated, the same operation as in the vertical direction can be performed. Further, if the upper and lower coil members 19 and the left and right coil members 19 are electrically heated, the bending tube portion 4 can be bent in either the left or right direction while being bent in either the up or down direction.

That is, according to the endoscope having the above configuration, the coil member 19 provided on the bending tube portion 4 and the first to fourth switches 9, 10, 11, 12 provided on the operation portion 1 are electrically connected. However, the bending tube portion 4 can be bent by an electric signal generated by operating these switches 9, 10, 11, 12. Therefore, no matter how the flexible tube section 3 which is the insertion section 2 between the bending tube section 4 and the operating section 1 is bent, its operation is not affected and the shape of the drive member 19 is changed. The bending tube portion 4 can be surely bent.

The present invention is not limited to the above embodiment, and various modifications can be made without changing the gist thereof. For example, in the above embodiment, the means for cooling the coil member 19 that has been electrically heated to a transformation temperature or lower may be natural cooling,
A cooling gas may be sent to the insertion portion 2 to perform forced cooling.

Further, although the drive member 19 is provided on the outer peripheral side of the tubular body 15 in the above embodiment, it may be provided on the inner peripheral surface side thereof, and in this way, the shape of the drive member 19 can be smoothly changed. Not only can this be achieved, but the outer diameter of the curved tube portion 4 can be reduced.

[Effects of the Invention] As described above, according to the present invention, the length of the bending drive member is shortened by electrically heating the bending drive member that is installed between both ends of the bending pipe and is made of a shape memory alloy. As a result, there are drawbacks such as being unable to reliably bend depending on the bending state of the insertion part like the conventional method of pushing and pulling the operation wire to bend the bending tube part, and requiring a large operation force. Is eliminated. In addition, the operation wire can be slidably inserted over the entire length of the insertion part,
Since it is not necessary to provide a mechanism for pushing and pulling the operation wire on the operation portion, the structure can be simplified. In addition, since the bending driving member is configured to be electrically heated through the bending tube portion, it is not necessary to dispose the lead wire along the bending tube portion, the number of parts can be reduced, and the diameter can be reduced. .

[Brief description of drawings]

FIG. 1 is a schematic configuration diagram of an endoscope showing an embodiment of the present invention, FIG. 2 is a perspective view of the internal structure of the bending tube portion, and FIG.
The figure is a side view of the most advanced tubular body as seen from the axial direction. 2 ... insertion part, 4 ... curved tube part, 15 ... tubular body, 19,30
…… Bending drive coil member.

 ─────────────────────────────────────────────────── ─── Continuation of the front page (72) Minoru Okada 2-43-2 Hatagaya, Shibuya-ku, Tokyo Olympus Optical Co., Ltd. (72) Shinroku Sogi 2-43-2 Hatagaya, Shibuya-ku, Tokyo No. Olympus Optical Co., Ltd. (72) Inventor Issei Kobayashi 2-34-2 Hatagaya, Shibuya-ku, Tokyo Olympus Optical Co., Ltd. (72) Inventor Koji Takamura 2-43 Hatagaya, Shibuya-ku, Tokyo No. 2 In Olympus Optical Co., Ltd. (72) Inventor Ryoji Masubuchi 2-43-2 Hatagaya, Shibuya-ku, Tokyo No. 2 In-line Optical Co., Ltd. (72) Inventor Katsuyuki Konpei 2-43, Hatagaya, Shibuya-ku, Tokyo No. 2 Olympus Optical Co., Ltd. Inside the panel of referees Chief referee Tetsuo Yasuda Referee Toshiaki Yoshida Referee Hatsuo Miyasaka (56) References Japanese Patent Application Laid-Open No. 57-164034 (JP, A) Japanese Patent Application Laid-Open No. 58-25140 (JP, A) Japanese Patent Application No. 57-96750 (Japanese Utility Model Application No. 59-2344). And a microfilm of the drawing contents (JP, U)

Claims (1)

[Claims] 1. A bending tube portion formed by connecting a plurality of electrically conductive tubular bodies provided in an insertion portion of an endoscope, and made of a shape memory alloy, installed between both ends of the bending tube portion. A bending drive member that is shortened in length by being electrically heated and one end of the bending drive member is electrically connected to the distal end side of the bending tube portion, and the bending end portion and the bending end portion of the bending tube portion are electrically connected. An endoscope comprising: a driving member, the other end of which is electrically connected to the other end of the driving member to electrically heat the bending driving member.