JPH0327603Y2 - - Google Patents

Description

[Detailed description of the invention] <Industrial application field> The present invention relates to a cable equipped with a bending mechanism, and is particularly useful when applied to optical fiber sensors such as medical or industrial endoscopes, or laser scalpels. It is.

<Conventional technology and problems> In optical fiber sensors for medical devices or industrial endoscopes, it is necessary to bend the imaging unit at the tip in a desired direction by external operation to capture a desired image. There are many things. An optical fiber sensor cable, as shown in FIG. 3, has been developed in response to such demands. In FIG. 3, a large number of nodal rings 10 are inserted around the optical fiber sensor body 9, and each nodal ring 10 is butted against a protruding fulcrum 11 provided at the center of each nodal ring 10. Also, a plurality of operating wires 12 are arranged symmetrically around each node ring, and by contracting one and extending the other, the tip imaging section of the optical fiber sensor is bent and moved in a desired direction. It has a structure that allows you to move towards it.
However, in the optical fiber sensor cable having such a structure, when the thickness of the cable increases due to the use of the joint ring 10, the frictional force of the operating wire 12 at the through hole of the joint ring 10 increases due to the length of the optical fiber sensor cable. Since it is accumulated as it increases, there is a drawback that the controllable distance is limited to within several meters. On the other hand, recently, the development of new technology has made it possible to manufacture image fibers that are the main body of optical fiber sensors with extremely small diameters and long lengths. In order to eliminate the above-mentioned drawbacks and further expand the field of application of optical fiber sensors, the development of new optical fiber sensors is expected. The present invention was made in view of the deficiencies of the prior art, and it is an object of the present invention to provide a cable that has a small outer diameter and is equipped with a bending mechanism that allows the tip end to be easily manipulated in a desired direction.

<Means for solving the problems> The cable according to the present invention, which has achieved the above-mentioned purpose, has a deformable member made of a shape memory alloy built into the sheath of the cable, and an electric current is applied to the deformable member to bring the deformable member to a predetermined temperature. and an operating device for bending the cable according to a predetermined memorized shape, the deformable member being formed in a linear shape and having a shape memory in the direction of the length of the wire, a plurality of deformable members substantially parallel to the axis of the cable,
The plurality of linear deformable members are built into the sheathing part, and further include the plurality of linear deformable members around the axis of the cable;
Another linear deformable member given a shape memory in the opposite direction to the linear deformable member is symmetrically built into the covering portion, and each of the plurality of linear deformable members and the linear deformable member symmetrically built into these It is characterized in that it is connected to other linear deformable members at the tip of the cable.

<Example> A cable equipped with a bending mechanism according to the present invention will be described with reference to the drawings of an example. FIG. 1 is a cross-sectional view of an optical fiber sensor cable equipped with a bending mechanism according to an embodiment of the present invention. FIG. 2 is a conceptual diagram illustrating the arrangement and operation of the linear deformable member shown in FIG. 1. In the optical fiber sensor cable equipped with the bending mechanism shown in FIG. 1, there is an image transmission section 1 consisting of an image fiber arranged in the center constituting the optical fiber sensor body, and an illumination light transmission section 2 arranged around it. A highly expandable and flexible cable sheathing section 3 is disposed surrounding the optical fiber sensor main body. Inside the cable sheathing section 3, a pair of deformable members 4a ₁ , 4a 2 ...4a 6 made of memory material and a pair of deformable members 4a 1 , 4a ₂ ... 4a ₆ and a pair of deformable members 4a 1 , 4a 2 . Other deformable members (hereinafter referred to as other deformable members) 4b _{1 , 4b 2 .} It is connected at the tip 3a with a conductor 5, and at the base 3b of the cable sheath 3, it is introduced into the operating device 6 by the conductor 5, and connected to a power source 8 via a resistor R and a switch 7. In the example shown in FIG. 2, when the switch 7 is turned on, current flows through the deformable member 4a ₁ and the other deformable member 4b ₁ located symmetrically to it, and the deformable member 4a ₁ generates heat due to its own electrical resistance, causing the surrounding Due to the conditions, the temperature is kept almost constant, and that temperature is the deformable member 4a ₁
When the transformation temperature reaches , the memory material such as TiNi wire forming the deformable member 4a ₁ returns to its memorized shape.
In this embodiment _, the deformable members 4a _{1 ,} . This results in different lengths between the two. Since the deformable member 4a ₁ and the other deformable member 4b ₁ are fixed to the cable sheathing section 3 at the tip end 3a and base 3b of the cable sheathing section, respectively, the cable sheathing section 3 is fixed to the cable sheathing section 3 as shown by the dashed line in FIG. Bend in the direction shown in a. Next, when the switch 7 is turned off and the deformable member _4a1 returns to room temperature, it returns to its original straight shape. Other pairs 4a ₂ and 4b ₂ ,...4a ₆ and 4b ₆
shows similar deformation depending on the power supply connection. Therefore, if the power source 8 of the operating device 6 is switched and applied to the pair shown at 4a ₆ and 4b ₆ , the cable sheath 3 is deformed in the direction shown by the arrow c in FIG. In the example shown in FIG.
Since a structure in which _{a 1} , . Therefore, in order to bend the cable sheathing portion 3 in the opposite direction, it is sufficient to rotate the entire cable body by 180 degrees and then apply electricity. In addition, as another method, another deformable member 4
Deformable members are buried closer to b ₁ , 4b ₂ ... 4b ₆ , respectively, and correspondingly deformable members 4a ₁ ,
If other deformable members are further buried in the vicinity _{of 4a 2 ,} . Further, in the operating device 6, only one resistor R can be used for energizing each deformable member. Note that by sequentially switching between a desired pair of one deformable member and another deformable member using the operating device 6, the cable sheathing portion 3 can be bent in a desired direction. Furthermore, as shown in FIG. 1, the cable sheath of the embodiment is equipped with an optical fiber sensor consisting of an image transmission part 1 made of an image fiber and an illumination light transmission part 2, so that by switching the switch using the operating device 6,
The imaging section at the tip of the optical fiber sensor can be turned in a desired direction. In order to bend the cable structure in which the optical fiber sensor is installed in the cable sheathing part 3 in the desired direction by the desired amount, it is necessary to resist the bending strength of the cable structure made up of the optical fiber sensor and the cable sheathing part 3. , the shape memory material must be designed to exhibit its restoring power. Furthermore, the optical fiber sensor cable as shown in FIG. 2 can be maintained at a desired bent position by delicately adjusting the resistance R in the operating device 6. Although the power source 8 is shown as a DC power source, it may be an AC power source or a pulse power source with adjustable pulse width or pulse period.

In the example of the optical fiber sensor cable shown in Figure 1, especially if it is long like an industrial optical fiber sensor cable, the only part that needs to be bent is about 5 cm at the tip of the cable. Up to that point, you can use normal lead wires instead of shape memory alloys.

Although the optical fiber sensor cable shown in FIG. 1 has been described as an example, the cable having the bending mechanism according to the present invention may have any main body within the sheathing part, such as an image transmission part using an image fiber, an illumination light A transmission section or a fiber for transmitting optical energy such as a laser scalpel may be covered with a cable covering section singly or in any combination thereof. For example, by inserting an energy transmission fiber made of AgBr, AgCl, etc. that transmits CO ₂ laser light well into the optical fiber sensor cable shown in Figure 1, the direction of laser irradiation can be controlled by bending the cable, allowing laser treatment. It can be an endoscope capable of

<Effects of the invention> According to the cable equipped with the bending mechanism according to the invention, the deformable member of the shape memory alloy incorporated in the highly elastic and flexible cable sheath is provided with a heating means by supplying electric current. Therefore, the disadvantage of having a significantly large outer diameter as in the case of conventional joint rings is eliminated, and it is advantageous that the outer diameter can be formed into a small diameter. In addition, by simply heating one of the multiple shape memory alloy thin wires in the cable sheath, the memory shape in the length direction, that is, the direction of expansion and contraction can be restored, and the image fiber cable etc. can be moved in the desired direction. Because it can be bent,
It does not require mechanical operating wires like conventional ones, and the operating distance can be extremely long.
In particular, it can be expected to be used in a wider range of industrial applications.

[Brief explanation of drawings]

Fig. 1 is a cross-sectional view of one embodiment of the present invention, Fig. 2 is a conceptual diagram for explaining the arrangement of deformable members and their functions shown in Fig. 1, and Fig. 3 is a diagram of a conventional optical fiber sensor cable. It is an explanatory view of a bending mechanism. In the drawings, 1 is an image transmission section, 2 is an illumination light transmission section,
3 is a cable covering part, 4a ₁ , 4a ₂ ... 4a ₆ is a deformable member, 4b ₁ , 4b ₂ ... 4b ₆ is another deformable member, 5 is a conductor, 6 is an operating device, 7 is a switch, and 8 is a power source .

Claims (1)

[Claims for Utility Model Registration] (1) A deformable member made of a shape memory alloy built into the sheath of the cable, and an operation of energizing the deformable member to bring the deformable member to a predetermined temperature and bend the cable into a predetermined memorized shape. the deformable member is formed in a linear shape and given shape memory in the direction of the length of the wire, and a plurality of deformable members are built into the sheathing section substantially parallel to the axis of the cable, and further, The plurality of linear deformable members and another linear deformable member given a shape memory in a direction opposite to that of the linear deformable members are built into the covering part symmetrically about the axis of the cable, and the A cable characterized in that each of the plurality of linear deformable members and the other linear deformable member built symmetrically therein are connected at a distal end portion of the cable. (2) The cable according to claim 1, characterized in that the covering portion covers an image transmission fiber. (3) The cable according to claim 1 or 2, characterized in that the covering portion covers a lighting fiber. (4) The cable according to claim 1, 2, or 3 of the utility model registration claim, characterized in that the covering portion covers an energy transmission fiber.