JPH11295615A - Endoscope - Google Patents

Abstract

PROBLEM TO BE SOLVED: To shorten the length of an actuator part, to secure a sufficient space for passing a filamentary body at the central part of an endoscope and to smoothly shake the head of the endoscope. SOLUTION: This endoscope is provided with a filamentary body 1 provided with a head shaking part 1a on the side of a top end and first and second wires 3 and 4 for head shaking connecting their top end parts to the top end part of the head shaking part 1a on a cross section oppositely an 180 deg. with respect to an axial center. This endoscope is provided with an actuator part 2 having first, second and third shape memory spring parts 5, 6 and 7 successively serially provided from the side of the top end along the filamentary body 1 so as to be extended/contracted in lengthwise direction, a first movable part 8 arranged at the border part of the first and second shape memory spring parts 5 and 6, and a second movable part 9 arranged at the border part of the second and third shape memory spring parts 6 and 7.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

[0001] The present invention relates to an endoscope.

[0002]

2. Description of the Related Art As an endoscope for observing the inside of a body or a thin tube, for example, as shown in FIGS.
The base end of the oscillating wire b for oscillating the oscillating portion a on the distal end side of the striated body c is connected to a ring body d slidably fitted to the striated body c, and the ring body A coil spring e is arranged on the distal end side of the ring member d, and a shape memory coil spring f shortened by heating is arranged on the proximal end side of the ring body d to form an actuator portion g. As described above, an endoscope in which the shape memory coil spring f of the actuator g is shortened by heating so that the oscillating portion a can be oscillated in one direction is known.

[0003]

However, in the above-mentioned conventional endoscope, the swing operation can be performed only in one direction. Also, to enable bidirectional swing operation,
It is necessary to provide two actuators g in series or in parallel. In this case, variations in friction and manufacturing errors in the individual actuators g occur, and a difference in traction force occurs during wire pulling, and a smooth operation cannot be obtained. And so on. And when they are provided in series, the length is doubled and the structure becomes complicated, which makes production difficult. In addition, when provided in parallel, there is a problem that components need to be reduced and a space around the striatum is occupied greatly.

Accordingly, the present invention solves the above-mentioned problems, and can shorten the length of the actuator portion, and can secure a sufficient space for passing the striatum at the center of the endoscope. Further, it is an object of the present invention to provide an endoscope which can suppress fluctuation of a swing due to friction or the like and can smoothly swing.

[0005]

In order to achieve the above-mentioned object, an endoscope according to the present invention comprises a striated body having a oscillating portion formed on the distal end side and the oscillating body in a cross section. And a first and second oscillating wires, the distal ends of which are connected at 180 ° opposite positions with respect to the axis with respect to the distal end of the part, in the longitudinal direction along the striatum. A first, a second, and a third shape memory spring, which are provided in series from the distal end side so as to be extendable and contractible, and are disposed at a boundary between the first shape memory spring and the second shape memory spring; A first movable portion connected to a base end of the first swinging wire; a first movable portion connected to a boundary between the second shape memory spring portion and the third shape memory spring portion; An actuator having a second movable portion connected to the base end.

A first heating state in which the first and third shape memory spring portions are heated and the second shape memory spring portion is not heated, a first heating state in which the second shape memory spring portion is heated, and a first and third state in which the second shape memory spring portion is heated.
It is configured to be switchable between a second heating state in which the shape memory spring portion is not heated. Further, the first, second, and third shape memory spring portions are formed in a coil spring shape that is elongated by heating, and are wound around the filament.

[0007]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS The present invention will be described below in detail with reference to the drawings showing embodiments.

In FIG. 1, FIG. 2, and FIG. 3, A is an insertion portion of an endoscope to be inserted into a blood vessel or the like of a human body. In this endoscope (insertion portion A), the distal end portions 3a and 4a are connected to the striatum 1 and the distal end portion of the oscillating portion 1a in a cross section at a position 180 ° opposite to the axial center. First and second swing wires 3,
4, an actuator unit 2 for selectively pulling the first and second oscillating wires 3 and 4 to drive the oscillating unit 1a to oscillate,
Is provided. In addition, the striatum 1, the actuator part 2, and the first
The second oscillating wires 3, 4 and the like are inserted into the tubular outer casing, but the outer casing is not shown in FIGS. 1, 2 and 3.

The striated body 1 includes a oscillating portion 1 formed on the distal end side.
a and a main body 1b extending toward the base end of the oscillating portion 1a. At least an image guide and a light guide are inserted into the striatum 1, and a working channel tube or the like may be inserted therein.

The actuator section 2 is provided with first, second, and third shape memory spring sections 5, 6, 7, which are extendable in the longitudinal direction along the striated body 1 and are provided in series from the distal end side.
A first movable portion 8 disposed at a boundary between the first shape memory spring portion 5 and the second shape memory spring portion 6; and a boundary portion between the second shape memory spring portion 6 and the third shape memory spring portion 7. And a second movable portion 9 disposed at the second position.

First, second, and third shape memory spring portions 5, 6,
Numeral 7 is made of a shape memory alloy, and is formed in a coil spring shape that is elongated by heating. Further, the first movable portion 8 and the second movable portion 9 are each formed in a ring shape. Then, a first movable portion 8 is interposed between the first shape memory spring portion 5 and the second shape memory spring portion 6, and between the second shape memory spring portion 6 and the third shape memory spring portion 7. The first, second, and third shape memory springs 5, 6, 7, and the first
The second movable parts 8 and 9 are externally fitted to the main body 1b of the linear body 1 in series. In other words, the first, second, and third shape memory spring portions 5, 6, 7 are wound around the striated body 1, and the first and second movable portions 8, 9 are slidably fitted to the main body 1b. I do.

Further, the tip of the first shape memory spring 5 is locked to the main body 1b of the striated body 1 {receiving the tip}.
A distal locking portion 10 and a proximal locking portion 11 for locking the proximal end of the third shape memory spring portion 7 {receiving the proximal end} are formed. Specifically, the distal locking portion 10 and the proximal locking portion 11,
An annular protrusion is provided fixedly on the outer peripheral surface of the main body 1b. Further, between the distal locking portion 10 and the proximal locking portion 11,
The first, second, and third shape memory spring units 5, 6, 7
It is assembled in a compressed state through the second movable portions 8 and 9 so as to oppose each other with a repulsive urging force in the compression direction. That is,
The first, second, and third shape memory spring portions 5, 6, and 7 are shortened from the state in which the shape has been recovered by heating to form a compression coil spring.

In this endoscope, as shown in FIG. 2, a first heating state in which the first and third shape memory spring portions 5, 7 are heated H, H and the second shape memory spring portion 6 is not heated. As shown in FIG. 3, the second shape memory spring section 6 is heated and the first and third
A second heating state in which the shape memory spring portions 5 and 7 are not heated;
Is configured to be switchable.

More specifically, the heating is performed by a not-shown energizing unit or a laser beam irradiating unit. That is, in the case of energization, the first and second movable parts 8 and 9 are formed of an insulator,
A power supply lead wire and a grounding lead wire are electrically connected to the second and third shape memory spring portions 5, 6, and 7, respectively; A control means capable of switching between energization of only the second shape memory spring portion 6 and energization of only the second shape memory spring portion 6 is provided. When using laser light, the first
At least three optical fibers for individually irradiating the laser light to the second and third shape memory spring portions 5, 6, 7 are provided.
Control means capable of switching between irradiation of only the third shape memory spring portions 5 and 7 and irradiation of only the second shape memory spring portion 6;
It may be provided.

Thus, as shown in FIG.
When only the shape memory spring portions 5 and 7 are heated H, H (ie, when the first heat state is set), the first and third shape memory spring portions 5 and 7 extend (recover the shape), Since the first movable portion 8 moves to the proximal end side and the first oscillating wire 3 is pulled to the proximal end side, the oscillating portion 1a moves toward the first oscillating wire 3 as shown by the arrow B. Bend. In addition, the second movable portion 9 moves to the distal end side, and the second oscillating wire 4 is connected to the oscillating portion 1.
Following the curvature of a, the second shape memory spring portion 6 is pressed from both sides and shortened. Thus, in the first heating state,
It is maintained in a curved state (head swing state) in the direction of arrow B as shown in FIG.

As shown in FIG. 3, when only the second shape memory spring portion 6 is heated to H (ie, when it is set to the second heating state), the second shape memory spring portion 6 is extended, 2 Since the movable portion 9 moves to the proximal end and the second oscillating wire 4 is pulled to the proximal end, the oscillating portion 1a is moved to the second position indicated by the arrow C (opposite to the arrow B direction). It bends toward the oscillating wire 4. In addition, the first movable portion 8 moves to the distal end side, and the first oscillating wire 3 follows the curvature of the oscillating portion 1a. At this time, the first and third shape memory spring portions 5 and 7 are pushed by the second shape memory spring portion 6 to be shortened. The force required to move the second movable portion 9 to the proximal side during the transition from the straight state of FIG. 1 to the curved (head swing) state of FIG. Since the force is greater than the force required to move 8 toward the distal end, the first shape memory spring section 5 starts to shrink first, and then the third shape memory spring section 7 shrinks when the balance is achieved. Thus, in the second heating state, a curved state (head swing state) in the direction of arrow C as shown in FIG. 3 is maintained.

In order to return from the swinging state as shown in FIG. 2 to the straight state as shown in FIG. 1, only the intermediate second shape memory spring portion 6 is heated weakly to such an extent that the shape cannot be completely recovered. do it. Also, in order to return from the swinging state as shown in FIG. 3 to the straight state as shown in FIG. 1, only the first shape memory spring section 5 and the third shape memory spring section 7 are not completely recovered. What is necessary is just to heat slightly.

As described above, according to this endoscope, the length of the actuator section 2 can be reduced. And,
The actuator section 2 is not bulky, and a sufficient space for passing the striatum 1 at the center of the endoscope can be secured. Further, the friction at the time of the swing is reduced, and the variation of the swing can be suppressed, and the swing can be performed smoothly.

The endoscope of the present invention can be modified in design in addition to the above-described embodiment.
In some cases, the third shape memory spring portions 5, 6, and 7 may be formed of one continuous shape memory alloy coil spring without being separated. In that case, the first part is provided in the middle of the coil spring.
The movable section 8 and the second movable section 9 may be provided in a fixed manner. The endoscope can be used not only for medical purposes but also for observing the inside of a thin tube for industrial use.

[0020]

Since the present invention is configured as described above, the following effects can be obtained.

According to the endoscope of the first aspect, the length of the actuator section 2 can be reduced (even though the head is swung in two directions). In addition, the actuator section 2 is not bulky, and a sufficient space for passing the striatum 1 at the center of the endoscope can be secured. Further, the friction at the time of the swing is reduced, the variation of the swing angle can be suppressed, and the swing can be performed smoothly.

According to the endoscope of the second aspect, it is possible to reliably perform the swing to the first swing wire 3 side and the swing to the second swing wire 4 side. According to the endoscope according to the third aspect, the structure is simplified and the endoscope can be easily manufactured. Further, the actuator section 2 can be made more compact.

[Brief description of the drawings]

FIG. 1 is an enlarged simplified side view of a main part of a non-heated state according to an embodiment of the present invention.

FIG. 2 is an enlarged simplified side view of a main part in a first heating state.

FIG. 3 is an enlarged simplified side view of a main part in a second heating state.

FIG. 4 is an explanatory view of a conventional example.

[Explanation of symbols]

 Reference Signs List 1 striatum 1a oscillating part 2 actuator part 3 first oscillating wire 4 second oscillating wire 5 first shape memory spring part 6 second shape memory spring part 7 third shape memory spring part 8 first movable Part 9 Second movable part

Claims (3)

[Claims] 1. A striated body having a oscillating portion formed on the distal end side,
In the cross section, 180 ° about the axis at the tip of the oscillating part
A first and a second oscillating wire having a distal end connected to the opposite position, and extendable in the longitudinal direction along the striatum so as to be sequentially provided in series from the distal end side. A first, a second, and a third shape memory spring portion, and a boundary portion between the first shape memory spring portion and the second shape memory spring portion and a base end portion of the first oscillating wire. A first movable part to be connected, a second movable part disposed at a boundary between the second shape memory spring part and the third shape memory spring part, and connected to a base end of the second oscillating wire; An endoscope comprising: an actuator unit having: 2. A first heating state in which the first and third shape memory springs are heated and the second shape memory spring is not heated, and a first and third state in which the second shape memory spring is heated and the second shape memory spring is heated. 2. The endoscope according to claim 1, wherein the endoscope is configured to be switchable between a second heating state in which the shape memory spring portion is not heated. 3. The endoscope according to claim 1, wherein the first, second, and third shape memory spring portions are formed in a coil spring shape that is elongated by heating, and are wound around the striated body. mirror.