JPH06327269A - Actuator device - Google Patents

Abstract

PURPOSE:To provide an actuator device which can transfer the amount of generated force and is capable of small displacement operation. CONSTITUTION:An actuator device 2 for curvature in upper and lower direction and for curvature in left and right directions is provided inside the area near the curvature part of an endoscope insertion part and then the actuator device 2 is mainly constituted of a fixed member 3 which is provided inside the endoscope insertion part, an operation wire 4 which is inserted into the fixed member 3 and where the tip is fixed near the tip inside the endoscope insertion part, and a bimorph type piezoelectric element 5 where a plurality of holes where the operation wire 4 is inserted are provided at a center part opposingly and where the an outer diameter is fixed to the inside of the fixed member 3. Then, the operation wire 4 is moved relatively for the fixed member 3 when a voltage is applied to the piezoelectric element 5 at one side and then the operation wire 4 is fixed to the fixed member 3 or when application of voltage is released for releasing the fixing of the operation wire 4 and the fixed member 3.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an actuator device used, for example, in a bending mechanism of an endoscope.

[0002]

2. Description of the Related Art In recent years, various solid displacement elements having displacement amounts such as magnetostriction, piezoelectric strain, and electrostriction of solids caused by changes in magnetic field and electric field as external factors have been developed and put into practical use. Displacement elements have begun to be used in various actuator devices in accordance with characteristics such as responsivity and displacement amount.

By the way, there is provided an endoscope capable of observing internal organs in a body cavity by inserting an elongated insertion portion into the body cavity and performing various kinds of medical treatments by using a treatment instrument inserted in a treatment instrument channel as necessary. Widely used. Among such endoscopes, some flexible endoscopes having a flexible insertion portion are provided with a bending portion capable of bending at the distal end side of the insertion portion, and the bending operation knob provided on the operation portion is operated. Then, the bending operation of the bending portion is performed by pushing and pulling the operation wire inserted through the insertion portion.

[0004]

However, in the bending operation as described above, particularly in the case of an endoscope having a long insertion portion,
Since the operation wire in the insertion section becomes long, it is difficult to sufficiently transmit the force of the operation section to the curved portion, and it is difficult to determine a minute curved amount.

The present invention has been made in view of the above circumstances. For example, even in a device such as a bending mechanism of an endoscope, the generated force can be sufficiently transmitted and a slight displacement can be achieved. It is an object of the present invention to provide an actuator device that can be operated.

[0006]

In order to achieve the above object, an actuator device according to the present invention is an actuator device having a moving member that moves relative to a fixed member, wherein the moving member can be released from the fixed member. And a solid displacement element that moves the moving member relative to the fixed member, is provided on at least one of the fixed member and the moving member.

[0007]

[Operation] In the above structure, the fixing of the moving member to the fixed member and the release of the fixing are performed by displacing the solid displacement element in a predetermined manner. Then, the relative movement of the moving member with respect to the fixed member displaces the solid displacement element to release the fixation between the fixed member and the movable member when fixing the fixed member and the movable member. When you do.

[0008]

Embodiments of the present invention will be described below with reference to the drawings. 1 to 3 show a first embodiment of the present invention, FIG. 1 is an explanatory diagram showing the structure and operation of an actuator device, FIG. 2 is an explanatory diagram showing the actuator device in an endoscope insertion portion, and FIG. It is a perspective explanatory view of a displacement element.

In these drawings, reference numeral 1 indicates an endoscope insertion portion, and an actuator device 2 is provided inside the endoscope insertion portion 1. This actuator device 2
Is provided on the upper side and the lower side inside the vicinity of the curved portion of the endoscope insertion portion 1 in the drawing so as to be able to bend the endoscope insertion portion 1 in the vertical direction (vertical direction in FIG. 2). A pair of actuator devices (not shown) are provided inside the endoscope insertion portion 1 so that the endoscope insertion portion 1 can be bent in the left-right direction.

Further, the actuator device 2 has a cylindrical fixing member 3 fixed inside the endoscope insertion portion 1.
And an operating wire 4 as an example of a moving member which is inserted through the fixing member 3 and whose tip is fixed near the tip inside the endoscope insertion portion 1, and the operation wire 4 which is substantially conical and has a central portion. A plurality of holes are formed through which the wires 4 are inserted, and a plurality of piezoelectric elements 5 are arranged so as to face each other, and the piezoelectric element 5 is an example of a solid displacement element whose outer diameter is fixed inside the fixing member 3. ing.

Further, each piezoelectric element 5 is a bimorph type piezoelectric element 5 formed by joining two piezoelectric thin plates 5a and 5b as shown in FIG. The piezoelectric thin plate 5a on the inner side (inside of the cone) expands, and the piezoelectric thin plate 5b on the outer side contracts. That is, when a voltage is applied in a free state, the outer diameter of the piezoelectric element 5 increases, and the diameter of the hole through which the operation wire 4 is inserted decreases, and further, the fixing in which the piezoelectric element 5 is arranged is fixed. The axial length of the member 3 (conical height dimension) is reduced.

Next, referring to FIG.
The operation of will be described. It should be noted that, in FIG. 1, only the operation of the pair of piezoelectric elements 5 of the actuator device 2 which are provided oppositely will be described.

First, as shown in FIG. 1 (a), when a voltage is applied to the piezoelectric element 5 on the right side in the figure from a state in which no voltage is applied to the pair of piezoelectric elements 5, it is shown in FIG. 1 (b). As described above, the inner diameter of the piezoelectric element 5 on the right side is contracted, and the operation wire 4 is sandwiched and pulled in the right direction. Here, since no voltage is applied to the piezoelectric element 5 on the left side, the operation wire 4 is moved to the right side.

Next, as shown in FIG. 1C, when a voltage is applied to the left piezoelectric element 5, the inner diameter of the left piezoelectric element 5 contracts, and the operating wire 4 is sandwiched and pulled leftward. . Here, since the operation wire 4 is fixed by the piezoelectric element 5 on the right side, the operation wire 4 does not move leftward and the piezoelectric element 5 on the left side does not move.
Fixed to.

Next, as shown in FIG. 1D, when the voltage application to the right piezoelectric element 5 is stopped, the right piezoelectric element 5 pushes the operating wire 4 to the left while
The fixation to the operation wire 4 is released. At this time,
Since the operation wire 4 is fixed by the left piezoelectric element 5, the operation wire 4 does not move leftward, and the fixation of the right piezoelectric element 5 to the operation wire 4 is released.

When the voltage application to the left piezoelectric element 5 is stopped, the left piezoelectric element 5 releases the fixation to the operation wire 4 while pushing the operation wire 4 in the right direction, as shown in FIG. Return to the state of (a). Here, since no voltage is applied to the piezoelectric element 5 on the right side, the operation wire 4 is moved to the right side.

By repeating this, the operation wire 4 is moved to the right side. The movement amount of the operation wire 4 can be adjusted by the number of times the above cycle is repeated. Further, when the operation wire 4 is moved to the left side, the right and left operations described above are reversed.

In order to bend the endoscope insertion portion 1 in the vertical direction, the actuator wire 2 provided on the upper side in FIG. 2 moves the operation wire 4 to the right side (on the operation section side), and the lower side. The operation wire 4 is moved to the left side (tip side) by the actuator device 2 provided in the. Then, the endoscope insertion portion 1 is bent upward as shown by a broken line in the figure. In addition, each operation wire 4 is moved by each actuator device 2 in the opposite direction to the above.
Is moved, the endoscope insertion portion 1 is bent downward. Similarly, when bending the endoscope insertion portion 1 in the left-right direction, the operation wires 4 are moved by a pair of actuator devices (not shown).

As described above, the amount of bending of the endoscope insertion portion is given by the amount of displacement of the piezoelectric element, and the displacement of the piezoelectric element can be adjusted by the number of repetitions, so the amount of bending of the endoscope insertion portion is very small. It is possible to reliably obtain with a large amount of displacement.

Further, since the actuator device can be provided in the vicinity of the curved portion of the endoscope insertion portion, the force generated in the actuator device can be efficiently and surely converted into the curved portion of the curved portion.

In the present embodiment, an example in which the actuator device is used for bending the endoscope insertion portion is shown, but the actuator device can also be used for devices other than the endoscope. Further, in this embodiment, since the moving member is the operation wire because it is the actuator device applied to the bending mechanism of the endoscope, when applied to other devices, the moving member may be a rod, a shaft or the like. .

Further, although the bimorph type piezoelectric element is used as an example of the solid displacement element in the actuator device of the present embodiment, the invention is not limited to this, and for example, a unimorph type piezoelectric element or the like may be used. For example, a solid displacement element that utilizes displacement other than piezoelectric strain such as magnetostriction may be used.

Next, FIG. 4 is an explanatory view showing the structure and operation of the actuator device according to the second embodiment of the present invention.
The second embodiment differs from the first embodiment in that the solid displacement element (piezoelectric element) of the actuator device is provided on the moving member (operation wire).

That is, as shown in FIG. 4, the actuator device 11 has a cylindrical fixed member 12, an operation wire 13 as an example of a moving member inserted through the fixed member 12, and a substantially conical shape. A bimorph-type piezoelectric element 14 as an example of a solid-state displacement element, which has a hole for inserting and fixing the operation wire 13 in the center and is arranged so as to face each other, is mainly configured.

Next, the operation of the actuator device 11 will be described. First, as shown in FIG. 4A, from the state in which no voltage is applied to the pair of piezoelectric elements 14,
When a voltage is applied to the piezoelectric element 14 on the right side of FIG.
As shown in (b), the outer diameter of the piezoelectric element 14 on the right side is enlarged, and the operation wire 1 is pressed while pressing the inner surface of the fixing member 12.
Pull 3 to the right. Here, since no voltage is applied to the left piezoelectric element 14, the left piezoelectric element 14 and the fixing member 12 are in a free state, and the operation wire 13 is moved to the right.

Next, as shown in FIG. 4 (c), when a voltage is applied to the left piezoelectric element 14, the outer diameter of the left piezoelectric element 5 increases, and the inner surface of the fixing member 12 is pressed while the above-mentioned pressure is applied. Pull the operating wire 13 to the left. Here, since the operation wire 13 is fixed by the piezoelectric element 14 on the right side, the operation wire 13 is fixed to the piezoelectric element 14 on the left side without moving leftward.

Next, as shown in FIG. 4 (d), when the voltage application to the right piezoelectric element 14 is stopped, the right piezoelectric element 14 pushes the operating wire 13 to the left while performing this operation. The fixing of the fixing member 12 to the wire 13 is released. At this time, the operation wire 13 is
Since it is fixed by the piezoelectric element 14 on the left side, the operation wire 13 does not move leftward, and the fixation of the fixing member 12 to the operation wire 4 by the piezoelectric element 14 on the right side is released.

When the voltage application to the left piezoelectric element 14 is stopped, the left piezoelectric element 5 is fixed to the fixing member 12 with respect to the operation wire 13 while pushing the operation wire 13 to the right. Is released, and Fig. 4 (a)
Return to the state of. Here, since no voltage is applied to the right piezoelectric element 4, the right piezoelectric element 14 and the fixing member 12 are in a free state, and the operation wire 13 is moved to the right. .

By repeating this, the operation wire 13 is moved to the right side relative to the fixing member 12 together with the piezoelectric elements 14. The operation wire 1
The movement amount of 3 can be adjusted by the number of repetitions of the above cycle. Further, when the operation wire 13 is moved to the left side, the right and left of the above-described operation are reversed.

As described above, by adopting the structure of the second embodiment, the same effect as that of the first embodiment can be obtained. The rest of the configuration and operation are the same as in the first embodiment, so a description thereof will be omitted.

Next, FIGS. 5 to 7 show a third embodiment of the present invention, FIG. 5 is an explanatory view showing an actuator device of a bending mechanism of an endoscope, and FIG. 6 shows the structure and operation of the actuator device. Explanatory drawing, FIG. 7 is a perspective explanatory view of a solid displacement element.
The third embodiment differs from the first embodiment in that the shape of the moving member is changed by the solid displacement element of the actuator device to obtain the amount of movement relative to the fixed member.

That is, inside the endoscope insertion portion 21, the endoscope insertion portion 21 can be bent in the vertical direction (vertical direction in FIG. 5). In the drawing, the bending portion of the endoscope insertion portion 21 is bent. Actuator devices 22 are provided on the upper and lower sides inside the vicinity, and a pair of actuator devices (not shown) are provided inside the endoscope insertion part 21 so that the endoscope insertion part 21 can be bent in the left-right direction. Has been.

Further, the actuator device 22 is fixed to a fixing member (not shown) inside the endoscope insertion portion 21 and its tip is fixed near the tip inside the endoscope insertion portion 21.
A knitting wire operation wire 23 as an example of a moving member having a swelling portion 23a formed by an elastic member in the middle, and a ring-shaped operation wire 23 provided around the swelling portion 23a of the above knitting wire operation wire 23. Piezoelectric element 2 as an example of a solid displacement element
It is mainly composed of 4 and.

The piezoelectric element 24 is formed so that its inner diameter contracts when a voltage is applied. The shape of the piezoelectric element 24 is shown in FIG.

In the actuator device 22 having the above structure,
When a voltage is applied to the piezoelectric element 24, as shown in FIG. 6 (b), the inner diameter of the piezoelectric element 24 contracts, and the bulging portion 23a of the braided wire 23 extends axially. As a result, the braided operating wire 23 is stretched in the axial direction.

When the application of the voltage to the piezoelectric element 24 is stopped, as shown in FIG.
3a again swells and the braided operation wire 23 contracts in the axial direction.

In order to bend the endoscope insertion portion 21 in the vertical direction, the operation wire 23 is contracted by the actuator device 22 provided on the upper side in FIG. 5, and the actuator device 22 provided on the lower side. The operation wire 23 is moved to the left side (tip end side) by. Then, the endoscope insertion portion 21 bends upward.
Further, if each operation wire 23 is moved by each actuator device 22 in the opposite direction to the above, the endoscope insertion portion 21 will bend downward. Similarly, when bending the endoscope insertion portion 21 in the left-right direction, the operation wires 23 are contracted / extended by a pair of actuator devices (not shown).

The number of actuator devices used in the bending mechanism of the endoscope and the number of piezoelectric elements used in the bulging portion of the operating wire are appropriately determined according to the amount of bending.

Next, FIGS. 8 to 11 show a fourth embodiment of the present invention, FIG. 8 is an explanatory view showing an actuator device of a bending mechanism of an endoscope, and FIG. 9 is an explanatory view showing the structure of the actuator device. 10 is an explanatory diagram of a voltage applied to the actuator device, and FIG. 11 is a perspective explanatory diagram showing the operation of the actuator device. In the fourth embodiment, the solid displacement element of the actuator device is formed of a laminated piezoelectric element, and the moving member is moved by moving the point of action with respect to the moving member (operation wire). Different from the one embodiment.

In these figures, reference numeral 31 indicates an endoscope insertion portion, and inside the endoscope insertion portion 31, a plurality of actuator devices 32 are provided. These actuator devices 32 are capable of bending the endoscope insertion portion 31 in the vertical direction (vertical direction in FIG. 8), and in the figure, the upper and lower sides inside the vicinity of the bending portion of the endoscope insertion portion 31. A plurality of actuator devices (not shown) are provided inside the endoscope insertion portion 31 so that the endoscope insertion portion 31 can be bent in the left-right direction.

Further, as shown in FIG. 9A, in each actuator device 32, a disk-shaped piezoelectric element 33 (33a to 33h) having a circular hole at its substantially central portion and an insulating layer 34 are alternately arranged. A laminated piezoelectric element 35 formed by laminating, and an operation wire 36 inserted through substantially the center of the laminated piezoelectric element 35.
And a fixing member (not shown) to which the laminated piezoelectric element 35 is fixed. Further, a predetermined clearance is formed between the laminated piezoelectric element 35 and the operation wire 36.

Each piezoelectric element 33 forming the laminated piezoelectric element 35 is provided with electrodes 37 for voltage application on both sides, as shown in FIG. 9B. The electrodes 37 of each of the piezoelectric elements 33 are divided into upper and lower parts with a horizontal line passing through the center of the circle as a boundary, and a space 38 is provided so as not to short-circuit.

On the other hand, as shown in FIG. 9B, the voltage application in this embodiment is performed by applying an AC voltage to the terminals A-B and C-D.
Of the piezoelectric elements 33, the piezoelectric elements 33a, 33c,
33e and 33g are connected to the terminal between A and B, and the piezoelectric elements 33b, 33d, 33f and 33h are connected to the terminal between C and D.

As shown in FIG. 10, the terminal between A and B and the terminal between C and D are applied with an AC voltage with a phase difference of 90 deg.

Next, FIG. 11 shows the principle of pulling and moving the operation wire 36. First, at time t = 0,
The piezoelectric elements 33b, 33d, 33f, 33h are compressed or contracted, and as shown in FIG.
Is transformed. At this time, when a constant tension is applied to the operation wire 36, the operation wire 36 receives a force from a part of the inner diameter of the laminated piezoelectric element 35.

Next, at time t = (1/2) π,
As shown in FIG. 11B, the piezoelectric elements 33a, 33c,
33e and 33g are compressed or contracted to form the laminated piezoelectric element 35.
Is transformed. As a result, the point receiving the force of the operation wire 36 moves, and the operation wire 36 is pulled to the left.

Similarly, as t = π, (3/2) π, the point receiving the force of the operating wire 36 moves as shown in FIGS. 11 (c) and 11 (d). The operation wire 36 is pulled to the left.

The operation wire 36 is pulled by continuously generating the above flow. In FIG. 10, the voltage applied to the terminal A-B is 90 degrees ahead of the voltage applied to the terminal C-D, but the phase difference is set to -90 deg. Is pulled in the opposite direction. Further, the pulling speed of the operation wire 36 can be changed by changing the frequency of the applied voltage. Further, the number of each piezoelectric element 33 constituting the laminated piezoelectric element 35 is not limited to the number in this embodiment. Furthermore, by operating an arbitrary actuator device, it becomes possible to bend an arbitrary curved portion.

[0049]

As described above, according to the present invention, even in a device such as a bending mechanism of an endoscope, the generated force can be sufficiently transmitted and a slight displacement can be achieved. Operation becomes possible.

[Brief description of drawings]

FIG. 1 is an explanatory diagram showing the structure and operation of an actuator device according to a first embodiment of the present invention.

FIG. 2 is an explanatory diagram showing an actuator device in an endoscope insertion portion according to the first embodiment of the present invention.

FIG. 3 is a perspective view illustrating a solid displacement element according to a first embodiment of the present invention.

FIG. 4 is an explanatory diagram showing the structure and operation of an actuator device according to a second embodiment of the present invention.

FIG. 5 is an explanatory view showing an actuator device of a bending mechanism of an endoscope according to a third embodiment of the present invention.

FIG. 6 is an explanatory diagram showing the structure and operation of an actuator device according to a third embodiment of the present invention.

FIG. 7 is an explanatory perspective view of a solid displacement element according to a third embodiment of the present invention.

FIG. 8 is an explanatory view showing an actuator device of a bending mechanism of an endoscope according to a fourth embodiment of the present invention.

FIG. 9 is an explanatory view showing the structure of an actuator device according to a fourth embodiment of the present invention.

FIG. 10 is an explanatory diagram of applied voltage to an actuator device according to a fourth embodiment of the present invention.

FIG. 11 is an explanatory perspective view showing the operation of the actuator device according to the fourth embodiment of the present invention.

[Explanation of symbols]

 2 Actuator device 3 Fixed member 4 Operation wire (moving member) 5 Piezoelectric element (solid displacement element)

 ─────────────────────────────────────────────────── ─── Continuation of the front page (72) Koichi Umeyama 2-43-2 Hatagaya, Shibuya-ku, Tokyo Inside Olympus Optical Co., Ltd. (72) Inventor Sakae Takehata 2-43-2 Hatagaya, Shibuya-ku, Tokyo No. Olympus Optical Co., Ltd. (72) Inventor Hitoshi Mizuno 2-43-2 Hatagaya, Shibuya-ku, Tokyo Olympus Optical Co., Ltd. (72) Hiroki Hibino 2-43-2 Hatagaya, Shibuya-ku, Tokyo No. Olympus Optical Co., Ltd. (72) Inventor Tatsuya Yamaguchi 2-43-2 Hatagaya, Shibuya-ku, Tokyo Inside Olympus Optical Co., Ltd.

Claims (1)

[Claims] 1. An actuator device having a moving member that moves relative to a fixed member, wherein the moving member is releasably fixed to the fixed member, and the moving member is relatively moved with respect to the fixed member. An actuator device in which a solid displacement element to be moved is provided on at least one of the fixed member and the moving member.