JPS6362213B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention provides an endoscope made of memory metal that enables arbitrary bending operations by disposing a memory metal in a curved part near the tip of a flexible tube of an endoscope inserted into a body cavity. This invention relates to a scope bending device.

A conventional flexible endoscope is configured as shown in the perspective view of FIG. 1, and the curved portion near the tip of the flexible tube inserted into the body cavity is configured as shown in the cross-sectional view of FIG. ing.

That is, in these figures, reference numeral 1 denotes an endoscope, which is composed of an operating section 2 and an insertion section 3, and the operating section 2 is an operation knob for bending an eyepiece section 4 and a bending section 5 provided on the insertion section 3. A flexible light guide cable 8 having a built-in light guide 7 for transmitting illumination light to the distal end of the insertion section 3 is connected, and the light guide cable 8 is connected to a light guide receptacle of a light source device (not shown). A light guide jack 9 is provided so as to be connected to the light guide jack 9.

An observation objective lens system 10 is housed in the distal end of the insertion section 3 approximately adjacent to the end surface of the light guide 7, and an image guide 11 is housed behind it. The optical image is transmitted to the eyepiece section 4, and by looking at the eyepiece section 4, the object at the tip of the insertion section 3 can be observed.

In order to enable wide observation of objects within the body cavity using the objective lens system 10 at the distal end of the insertion section 3, the following bending means is provided in the curved section 5 near the distal end.

The outer tube 12 of the curved portion 5 is made of a flexible material such as rubber, and the light guide 7 and the image guide 11 are housed inside thereof in the axial direction.
A large number of annular joint pieces 13, 13..., 13 are provided on the outside of the
are cascaded in the axial direction.

The cascade of these joint pieces 13, 13,..., 13 is
In order to enable the tip of the insertion portion 3 to bend upward and downward and in the left and right directions perpendicular to this in FIG. Wires 14, 14, 14, 1 for vertical and horizontal bending operations along
4 are inserted through and supported by the wire receivers 15, 15, . . . in the vicinity of the pivot portions of the joint pieces 13, 13, .

Each of the wire receivers 15, 15, . . . , 15 is fixed to the inner periphery of the joint pieces 13, 13, .

The tips of the wires 14, 14, 14, 14 are each fixed to the inner surface of the tip 16 of the insertion section 3, while the other end extends to the operating knob 6, which has two )
By rotating the wire 6, the two wires 14, 14 for up and down or left and right of the two sets expand and contract, so that the bending part 5 can be bent in the up and down direction, the left and right direction, and a combination thereof. It is composed of

In this way, by rotating the operation knob 6, the wires 14, 14, 14, 1 accommodated in the insertion section 3 are removed.
4 and bending the joint pieces 13, 13, . Even if you do this, the response on the tip side may be delayed, or the wire
4, 14 and the joint pieces 13, 13, . . . , 13 are made only by pulling and relaxing the wires 14, 14, 14, 14, so there is a problem that the amount of curvature is not determined depending on the operation of the operation knob 6. It was hot.

Another problem is that when the wires 14, 14, 14, 14 are cut, it is difficult to repair them.

This invention has been made in view of the above-mentioned problems, and includes a memory metal formed to expand and contract at a predetermined temperature above and below a predetermined temperature between the joint pieces of the curved part, and It is an object of the present invention to provide an endoscope bending device using a memory metal, which enables almost arbitrary bending by providing a means for heating the memory metal by supplying an electric current.

The present invention will be specifically described below with reference to the drawings.

FIG. 3 shows a first embodiment of the invention, which is constructed as described below.

As described in the conventional example, a large number of substantially annular joint pieces 21, 21, .
..., 21 are two pivot parts 22 each in the vertical direction and in the horizontal direction perpendicular thereto, as shown in FIG.
22, . . . , 22; 23, 23, .

The joint pieces 21, 21, . . . , 21 are arranged along the lines connecting the pivot parts 22, 22, . . . , 22; 23, 23, .
In between are memory metals 24, 24, ..., 24; 25, 2 shaped into a wave (single harmonic wave shape).
Both ends of 5, . . . , 25 are each fixed to the inner surface by brazing or the like. In the illustration, (shape) memory metals 24, 24,..., 24; 25, 2
Although the shapes 5, .

In general, (shape) memory metals are made of nickel-titanium alloys, copper-zinc-aluminum alloys, etc., and have a predetermined transformation temperature (this depends on the alloys used and their composition ratios, etc., and in this invention, the temperature is lower than body temperature). The structure changes at temperatures above and below the boundary (a few tens of degrees Celsius is desirable for operation. Since it has a shape memory effect that memorizes the shape of each phase, by processing the shape of each phase in advance, it can be made to exhibit each shape above and below the transformation temperature.

Each of the memory metals (alloys) 24, 24,..., 2
4; 25, 25, ..., 25 maintains the shape shown in the figure in the martensitic phase and keeps the curved part in a straight line, and in the high temperature phase above the transformation temperature due to heating, it curves along the central axis of the insertion part. Lead wires (conductor wires) 26, 26, .
26; 27, 27, ..., 27 are connected, and by supplying current to a pair of arbitrary (including specific times) lead wires (these lead wires are represented by 26a, 26a or 27a, 27a). The lead wires 26a, 26a or 27a, 27a are configured to heat a wavy memory metal (represented by 24a or 25a).

Therefore, when attempting to bend the bending portion by a desired amount in the vertical or horizontal direction, the (each) memory metal 24a or 25a (however, 1
By supplying current through the lead wires 26a, 26a or 27a, 27a connected to both ends of the (not necessarily limited to Can be curved. Alternatively, by combining vertical and horizontal bending operations, it is possible to bend in a wide range of directions.

In the above embodiment, each memory metal 24, 2
The amount of curvature of 4,..., 24; 25, 25,..., 25 when heated can be freely set within a wide range by adjusting the distance between both fixed ends, the number of times it is folded in a wave shape, the length of each folded side, etc. can.

The second embodiment shown in FIG. 4 differs from the first embodiment in that the memory metals 24, 24, ..., 24; 25, 25,
..., 25 are replaced by plate-shaped memory metal 28,
28,...,28;29,29,...,29 are arranged, and each of these plate-shaped memory metals 28,28,...,2
8; Connect one end of each of 29, 29,..., 29 to joint piece 2
1, 21, . . . , 21, and each other end is slidably fixed.

In this embodiment as well, the shape as shown in the figure is maintained in the martensitic phase of the low-temperature example, and the shape is formed so as to curve inward or outward in the high-temperature phase.

Therefore, in the same manner as in the above embodiments, a current is supplied to the predetermined plate-shaped shape memory metal 28a or 29a through the lead wires 26a, 26a or 27a, 27a at both ends thereof to heat it and transform it into a high-temperature phase. Accordingly, the shape memory metal 28a or 29a can be bent inward or outward, and the joint pieces 21a, 21a having both ends fixed (one end fixed and the other end slidably fixed) can be curved. Therefore, by applying the above to one or more shape memory metals 28a or 29a at a desired position, it is possible to curve the metal in a wide range of directions such as vertically or horizontally as desired.

The third embodiment shown in FIG. 5 shows the memory metals 24 arranged vertically and horizontally in the first or second embodiment.
24,...,24; 25,25,...,25 or 2
8, 28,..., 28; 29, 29,..., 29 are replaced by arcuate or semicircular memory metals 30, 3, respectively.
0, ..., 30; 31, 31, ... 31 on both sides near each pivot part 22, 22, ..., 22; 23, 23, ..., 23 of the vertical and horizontal joint pieces 21, 21, ..., 21 It was established in

Arcuate to semicircular memory metal 30, 30,..., 3
0; 31, 31, ... 31 have joint pieces 21,
They are inserted into the insertion holes of 21, . . . , 21 and fixed by brazing or the like.

Also in this embodiment, each memory metal 30, 30,
..., 30; 31, 31, ...31 maintains the shape shown in the figure in the martensitic phase on the low temperature side, keeping the curved part straight, and in the high temperature phase, the shape becomes more curved (reducing the radius of curvature). It is formed by processing as shown (in this case, it may be formed by processing so as to increase the radius of curvature).

Therefore, in substantially the same manner as described above, a pair (or several pairs) of lead wires 26a, 26a or 27a, 2 are attached to the memory metal 30a or 31a in the desired vertical or horizontal direction.
By supplying an electric current through 7a and heating it, it is possible to curve the predetermined joint pieces 21a, 21a and even the curved portions in directions such as left and right or up and down. Memory metal 30, 30,..., 30; 31, 3
1, . . . 31 are memory metals 25, 2 disposed in the left and right and up and down directions in the first (and second) embodiment.
5,...,25; corresponds to 24,24,...,24. ).

The fourth embodiment in FIG. 6 is the heating lead wires 26, 26, ..., 26; 27, 2 in the first embodiment.
Lead wires 26, 26,..., 26; 27, 27,..., 2 are obtained by connecting two adjacent pieces of 7,..., 27 in series in the vertical and horizontal directions, respectively.
This shows the number of pieces of 7 cut in half.

In this case, they are connected in series, but they may be connected in parallel depending on the case (this also applies to the following embodiments).

The above-mentioned embodiment can naturally be applied to the embodiment shown in FIG. 4 or 5, and is not limited to two connected in series as shown in the figure, but three or more connected in series. Connect to the twisted lead wire 26,
The number of 26, . . . , 26; 27, 27, . . . , 27 can also be reduced.

That is, FIG. 7 shows the front part 5A and the rear part 5 of the curved part.
Memory metals 24, 24, ..., 24; 25, 25, ..., 25 in the vertical and horizontal directions housed in B
(only the symbols of the first embodiment are shown) are connected in series, and the lead wires 26, 26,..., 26;
A fifth embodiment is shown in which the number of lines 7, 27, . . . , 27 is sufficiently reduced.

The sixth embodiment shown in FIG. 8 has lead wires 26, 26, . . . , 26 connected in the embodiment shown in FIG.
27, 27, ..., 27, the front part 5A and the rear part 5
B is shown in which the upper and lower parts and the left and right parts are connected in series.

Therefore, in this case, in one operation, the front part 5A and the rear part 5B are bent in opposite directions as shown in the figure, thereby performing a substantially S-shaped bending operation.

Not limited to the embodiment shown in FIG. 8, it is also possible to connect in combination in the vertical direction and the horizontal direction, or only the front part 5A and rear part 5B as in the embodiment shown in FIGS. 7 and 8. Instead, the above-mentioned lead wires 26, 26, ..., 26; 27,
It is also possible to apply the connection means of 27, . . . , 27.

Incidentally, by dispersing the bending parts in the insertion part, it is possible to perform a bending operation over a wide distance range.

As described above, according to the present invention, even in an endoscope whose insertion section is several meters or more in length, reliable and highly reproducible bending operation is possible. By applying current to and heating the shape memory alloy, the shape memory alloy is deformed and the spacing between the joint bodies changes, which has the advantage of enabling bending operations in a plurality of shapes.

Further, in the present invention, since the lead wire only supplies current, there is almost no risk of disconnection unlike the operating wire in the conventional example.

Furthermore, the present invention has the advantage that it can be applied even to cases where curved portions are scattered at distant positions.

Furthermore, the joint body increases the strength of the insertion portion of the endoscope, and provides excellent effects such as being able to effectively protect each component inserted through the joint body.

[Brief explanation of drawings]

FIG. 1 is a perspective view showing the appearance of a conventional flexible endoscope, and FIG. 2 is a sectional view showing the configuration of a conventional bending section.
3 is a sectional view showing a first embodiment of the invention, FIG. 4 is a sectional view showing a second embodiment of the invention, and FIG. 5 is a sectional view showing a second embodiment of the invention.
The figure is a sectional view showing a third embodiment of the invention, FIG. 6 is a sectional view showing a fourth embodiment of the invention, FIG. 7 is a perspective view showing a fifth embodiment of the invention, and FIG. 8 is a sectional view showing a fourth embodiment of the invention. FIG. 6 is a perspective view showing a sixth embodiment of the invention. 5... Curved portion, 21... Joint piece, 22, 23...
...Pivot part, 24, 25, 28, 29, 30, 31
...Memory metal, 26, 27...Lead wire.

Claims (1)

[Scope of Claims] 1. An insertion section of an endoscope, a curved section formed in the insertion section, a plurality of joint bodies provided within the curved section, and a shape memory alloy disposed between each of the joint bodies. An endoscope bending device using a memory alloy, characterized in that the shape memory alloy is provided with: means for passing an electric current through and heating the shape memory alloy to enable arbitrary bending operations.