JPH0611475B2 - Bending exercise device - Google Patents

Description

Description: TECHNICAL FIELD The present invention relates to a bending exercise device capable of bending a tip portion so as to move it to an arbitrary position in a three-dimensional space within a predetermined range.

[Prior art]

In a conventional manipulator, generally, a rotational movement, a turning movement, and an extension / contraction movement are combined to move the tip end portion of the arm portion to an arbitrary position in a three-dimensional space. Therefore, there is a drawback that it cannot be used for the purpose of inserting the tip of the arm into a narrow space.

[Object of the Invention]

The present invention has been made in view of the above circumstances,
It is an object of the present invention to provide a bending motion device capable of moving a tip portion to a desired position in a three-dimensional space at high speed with a large force by the bending motion.

[Structure of Invention]

The bending exercise apparatus according to the present invention stores a long flexible core body and a predetermined length respectively, and one end side is one end side of the core body and the other end side is the other end of the core body. Three or more linear shape memory alloys fixed to each side, guide means for guiding each of these shape memory alloys so as to extend along the core, and each of the shape memory alloys heated independently. The shape memory alloy has a length memorized in a state where all of the shape memory alloys have a temperature equal to or lower than a certain temperature, the core is in a straight state or has an arbitrary curved shape. When the shape becomes a predetermined neutral shape selected in advance, all of the shape memory alloy is stretched and deformed as compared with the memorized length by being pulled by the core body. It is the length.

Note that, for example, when a wire rod that is curved or bent in a spiral shape or a zigzag shape is pulled, the pitch of the spiral shape and the zigzag shape formed by the wire material becomes large, so that apparently,
The wire rod extends, but the deformation occurring in the wire rod at this time is actually bending deformation or twisting deformation,
Macroscopically, the accumulation of these bending and torsional deformations seems to cause elongation. In the present specification, the term “elongational deformation” refers to pure elongational deformation that does not include macroscopic elongation due to bending deformation or torsional deformation as described above.

[Action]

In the present invention, when each shape memory alloy is heated to a constant temperature zone, the shape memory effect causes the shape memory alloy to shrink in an attempt to return to the length memorized by the alloy. The amount of shrinkage of each shape memory alloy corresponds to the amount of thermal energy input to each alloy. Therefore, by selecting the shape memory alloy to be heated and by selecting the magnitude of the thermal energy input to each alloy, the core body is bent from a predetermined neutral state to a desired direction and size. You can

〔Example〕

 Hereinafter, the present invention will be described based on embodiments shown in the drawings.

1 to 4 show an embodiment of the present invention. In these figures, 1 is a bundle of optical fibers (hereinafter referred to as an optical fiber bundle), and in the present embodiment, the optical fiber bundle 1 is a core. Discs 2, 3 and 4 are fixed to the optical fiber bundle 1 at appropriate intervals (note that 2 is the disc on the leading edge side, 4 is the disc on the rearmost end side, and 3 is the middle thereof). Showing any number of discs arranged in). In addition, the optical fiber bundle 1 includes the respective discs 2, 3,
4 penetrates through the central part.

The disk 2 on the most distal side has three linear Ti-Ni
One ends of shape memory alloys 5a, 5b, 5c such as alloys are fixed at intervals of 120 degrees around the optical fiber bundle 1. Then, the shape memory alloys 5a, 5b, 5
The other end of c is fixed to the disk 4 on the rearmost end side at intervals of 120 degrees with the optical fiber bundle 1 as the center. Further, a pipe 6 made of fluororesin is attached to each of the intermediate disks 3 at a position corresponding to the fixed position of the shape memory alloys 5a, 5b, 5c with respect to the disks 2, 4, and these pipes are attached. As shown in FIG. 3, shape memory alloys 5a, 5b, and 5c are inserted into 6 so as to be freely movable in the axial direction. Disc 3
The pipe 6 and the pipe 6 are the shape memory alloy 5 in this embodiment.
A guide means for guiding the a, 5b, and 5c so as to extend along the optical fiber bundle 1 (core body), respectively.

Here, in the present embodiment, the core body, that is, the neutral state of the optical fiber bundle 1 is set to a state in which the optical fiber bundle 1 is straight. In addition, the shape memory alloy 5
a, 5b, 5c store a straight shape having a predetermined length by being subjected to a predetermined shape memory process.
In the initial state of the apparatus (the state where the optical fiber bundle 1 is straightened, has the neutral shape in this embodiment, and all of the shape memory alloys 5a, 5b, 5c are below a certain temperature), Each alloy 5a, 5b, 5c
Are the disks 2, 4 in a state where they are stretched and deformed by being pulled by the optical fiber bundle 1 as compared with the stored length.
It is in a state of being stretched between.

The tip of each shape memory alloy 5a, 5b, 5c is
As shown in the figure, they are connected to the output of the current-carrying device 8 via conductors 7a, 7b, 7c, respectively. Further, the rear end portions of the shape memory alloys 5a, 5b, 5c are connected to the output of the current-carrying device 8 via conductors 9a, 9b, 9c, respectively (in FIG. 4, conductors 7a-7c). And 9a-9c are omitted).

Here, the energization device 8 receives the signal e,
The shape memory alloys 5a, 5b and 5c are independently supplied with electric currents through which the electric power corresponding to the input signal e is obtained through the conductors 7a to 7c and 9a to 9c. Further, the conductors 7a to 7c and 9a to 9c
Are inserted into the intermediate disc 3 so as to be freely movable in the axial direction.

Next, the operation of this embodiment will be described.

When a certain amount of current is applied from the energization device 8 to only the shape memory alloy 5c, the alloy 5c is heated by Joule heat to reach a certain temperature or higher, starts phase transformation, and returns to the memorized shape by the shape memory effect. To try. Therefore, in view of the expansion / contraction direction, the shape memory alloy 5c tends to contract. Since the other shape memory alloys 5a and 5b are still subjected to the initial elongation deformation, the optical fiber bundle 1
Bends toward the shape memory alloy 5c as shown in FIG.

Similarly, from the energization device 8 to the shape memory alloy 5a or 5
When a current is applied only to b, the optical fiber bundle 1 is bent toward the shape memory alloy 5a or 5b, respectively. Also, shape memory alloys 5a and 5b, 5b and 5c, or 5c
If currents are simultaneously applied to and 5a, the optical fiber bundle 1 bends in the intermediate direction between the shape memory alloys 5a and 5b, the intermediate direction between 5b and 5c, or the intermediate direction between 5c and 5a.

Here, the amount of shrinkage of each of the shape memory alloys 5a, 5b, 5c when each of the alloys 5a, 5b, 5c is energized (that is, the length of each alloy 5a, 5b, 5c approaches the memorized length). Corresponds to the state of progress of the phase transformation of each alloy 5a, 5b, 5c, and thus the amount of thermal energy input to each alloy 5a, 5b, 5c. Therefore, the bending direction and the bending size of the optical fiber bundle 1 can be controlled by controlling the magnitude of the electric power applied from the current-carrying device 8 to each of the alloys 5a, 5b, 5c. Can be moved to any position in the three-dimensional space within a certain range.

Therefore, in the present embodiment, as described above, the optical fiber bundle 1 is curved in a desired direction, and the tip end of the optical fiber bundle 1 is positioned at a desired position, and the optical fiber bundle 1 is moved from the front end to the rear end. Light can be transmitted to the section (for example, when the optical fiber bundle 1 is inserted into a narrow passage such as a pipe and the inside of the passage is observed,
Moreover, in the case where the passage has a branching portion, the shape memory alloys 5a, 5b, 5c are energized to bend the optical fiber bundle 1 in a desired branching direction as described above, so that the optical fiber bundle 1 is made into a desired one. While intruding in the branching direction,
It becomes possible to transmit light from the front end to the rear end of the optical fiber bundle 1).

Here, in general, the recovery force generated in the process of recovering the shape memory alloy from the deformed state to the memorized shape is more remarkable when the shape memory alloy is subjected to extensional deformation than when the shape memory alloy is subjected to bending deformation or torsional deformation. It is well known that the larger the size, the faster the shape memory alloy recovers from the deformed state to the memorized shape.

Since this bending motion device utilizes the shape recovery from the elongation deformation of the shape memory alloys 5a, 5b, 5c, the optical fiber bundle 1 can be bent with a large force and at a high speed.

In the present embodiment, the shape memory alloys 5a, 5b, 5c memorize the straight shape, but as described above, the shape recovery force of the shape memory alloy is bending deformation when it is from elongation deformation. Since it is significantly larger than that of the shape memory alloys, a similar effect can be obtained even if the shape memory alloys 5a, 5b, 5c memorize the bent shape as long as the predetermined length is memorized.

Further, in this embodiment, the intermediate disk 3 and the shape memory alloy 5 are used.
Pipe 6 made of fluororesin between a, 5b and 5c
As described above, the optical fiber bundle 1
There is no possibility that a large friction will occur between the shape memory alloys 5a, 5b, 5c and the disc 3 when the is bent, and the bending operation will be hindered.

Further, although three shape memory alloys are used in the above embodiment, it goes without saying that four or more shape memory alloys may be used so that they can be heated independently.

Further, in the above embodiment, the shape memory alloys 5a, 5b, 5c are used.
Is heated by directly energizing the alloy,
In the present invention, it goes without saying that the shape memory alloy may be heated by other methods.

Further, in the above embodiment, the neutral shape of the core body (fiber bundle 1) is a straight state of the core body, but in the present invention, the specific curved state may be the neutral state of the core body.

Further, in the above-mentioned embodiment, although the optical fiber is used as the core, it is needless to say that a material other than the optical fiber such as a piano wire can be used as the core depending on the application, and only the bending operation is performed. As for the core, any core may be used as long as it can withstand a compressive force generated as a reaction that gives elongation deformation to the shape memory alloy.

〔The invention's effect〕

As described above, the bending motion apparatus according to the present invention can move the tip portion to an arbitrary position in the three-dimensional space within a certain range by (a) bending motion.

(B) Since the shape recovery force from the elongation deformation of the shape memory alloy is used, the core body can be bent with a large force and at a high speed.

It is possible to obtain excellent effects such as.

[Brief description of drawings]

FIG. 1 is a plan view showing an embodiment of a bending exercise apparatus according to the present invention, FIG. 2 is a side view showing the embodiment, and FIG. 3 is a penetrating state of a shape memory alloy with respect to an intermediate disk in the embodiment. FIG. 4 is an enlarged cross-sectional view, and FIG. 4 is a perspective view showing a curved state of the embodiment. 1 ... Optical fiber, 3 ... Disc (guide means), 5
a, 5b, 5c ... Shape memory alloy, 6 ... Pipe (guide means), 8 ... Energizing device.

 ─────────────────────────────────────────────────── ─── Continuation of the front page (72) Inventor Eiichi Nakano 10 of 427 Tehiro, Kamakura City, Kanagawa Prefecture (56) References: Showa 59-2344 (JP, U)

Claims (1)

[Claims] 1. A long flexible core body, which stores predetermined lengths, one end side of the core body and the other end side of the core body, respectively. Fixed 3
A plurality of linear shape memory alloys, guide means for guiding each of these shape memory alloys to extend along the core, and means for independently heating each shape memory alloy. The length memorized by each of the shape memory alloys is preselected from a straight state of the core body or an arbitrary curved shape in a state where all of the shape memory alloys have a constant temperature or less. When it has a predetermined neutral shape, all of the shape memory alloy has a length such that when it is pulled by the core body, it is subjected to extensional deformation as compared with the memorized length. Characteristic bending exercise device.