JP2849794B2 - Optical actuator device - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an optical actuator device, and more particularly, to an optical actuator device suitable for application to micromachine technology requiring a mechanical operation in a narrow area.

[0002]

2. Description of the Related Art Conventionally, it has been applied to medical use, inspection and repair of aircraft engines and nuclear power plants, etc.
In addition, the use of a so-called micro-machine device for reliably performing a functional mechanical operation in an extremely limited small space is being studied. By the way, an actuator device is most widely adopted as a device for ensuring a functional mechanical operation. And
As the actuator device, a configuration in which a driving piece is connected to a driving source such as a motor via a driving force transmission mechanism such as a ball screw is employed. In particular, a motor driven by electric energy is most generally adopted as the driving source, since it is preferable that the driving source can be easily and accurately controlled at a place considerably away from a very limited small space.

Therefore, the driving source, the driving force transmitting mechanism and the driving piece are introduced into a small space in a compact integrated state, and the driving source and an external remote control device are connected by a power cable, Power on by remote control
A desired operation can be performed by performing -OFF control or the like.

[0004]

However, when fabricating a micromachine device by incorporating the above-described actuator device, the dimensions of the entire micromachine device generally depend on the size of a small space as a work area. Since it is limited, an actuator device having a size sufficiently smaller than this size must be employed. In particular, in the case of a micromachine device introduced into a blood vessel or the like of a human body, the size of the actuator device must be significantly reduced. Therefore, it is necessary to set the accuracy of a device for producing a large number of components constituting the actuator device to, for example, a micron order or a submicron order.
Further, when all the components are manufactured on the order of microns or submicrons, assembling all of these components requires assembling accuracy at the same level as when manufacturing. Therefore, as for the manufacturing and assembling, not only the workability is remarkably reduced with the downsizing of the micromachine device, but also the cost is remarkably increased.

Under these circumstances, there is no particular problem if the working area is relatively large, but if the working area is extremely small, an actuator that satisfies the manufacturing accuracy and assembly accuracy described above. It is almost impossible to obtain a device, and as a result, the size of the working area to which a micromachine device incorporating an actuator device can be applied cannot be expanded to a narrow side.

This inconvenience becomes more remarkable when, for example, it is necessary to simultaneously drive a plurality of operating units by transmitting the driving force via mutually independent driving force transmitting mechanisms. In view of such a problem, the present applicant assigns a piston to one end of an optical fiber optically coupled to a light source, and to project the piston from the free end of the cylinder to the other end. And an optical actuator device having a configuration in which a light absorbing fluid is contained in a space formed by the other end surface of the optical fiber, the inner surface of the cylindrical body, and the base end surface of the piston (Japanese Patent Laid-Open No. 5-1705). reference).

However, in the optical actuator device having this structure, the piston can be simply reciprocated in one direction. For example, it is necessary to transmit the driving force via mutually independent driving force transmission mechanisms. Therefore, when it is necessary to operate a plurality of operation units at the same time, a plurality of optical actuator devices are employed, and additional devices for regulating the relative positions of the optical actuator devices are required.

[0008]

SUMMARY OF THE INVENTION The present invention has been made in view of the above-mentioned problems, and can achieve simplification and downsizing of the structure of a micromachine device, greatly suppress the complexity of the structure, and simultaneously operate a plurality of micromachine devices. It is an object of the present invention to provide an optical actuator device that can apply a driving force to an operation unit.

[0009]

According to a first aspect of the present invention, there is provided an optical actuator device, wherein one end is connected to the other end of an optical fiber having one end optically coupled to a light source. The other end of the cylindrical body having a plurality of branched portions is attached, and a driving piece is inserted into the plurality of branched portions of the cylindrical body so as to be movable in the axial direction of the branched portions, respectively. A light-absorbing fluid is contained in a space formed by the end face, the inner surface of the cylindrical body, and the driving piece.

[0010]

According to the optical actuator device of the first aspect, one end of the optical fiber optically coupled to the light source is attached to the other end of the optical fiber. A driving piece is inserted into the plurality of branch portions of the cylindrical body so as to be movable in the axial direction of the branch portion, and a light absorbing material is formed in a space formed by the other end surface of the optical fiber, the inner surface of the cylindrical body, and the driving piece. Since the fluid is contained, when light emitted from the light source is guided through the optical fiber and introduced into the cylinder, the light-absorbing fluid absorbs the light and expands. Then, since the light absorbing fluid expands in a state of penetrating deeper into all the branch portions, all the driving pieces are moved in the axial direction of the corresponding branch portion of the cylinder with the expansion of the light absorbing fluid. . Therefore, a plurality of driving pieces can be moved at the same time simply by inflating a single light absorbing fluid with a single light source. be able to. Further, when the required movement amount differs for each driving piece, the inner diameter of each branch may be set in accordance with the required movement amount.

More specifically, the intensity of light guided through the optical fiber and introduced into the cylinder, and the expansion rate of the light-absorbing fluid when light of a unit intensity is irradiated for a unit time are known. Thus, for example, by controlling the lighting continuation time of the light source (or the ratio of the lighting time in the case of intermittent lighting), the expansion amount of the light-absorbing fluid can be controlled. Since one end of the cylindrical body is branched into a plurality of portions, the expansion of the light-absorbing fluid affects all the branch portions, and as a result, a plurality of driving pieces move at the same time. And the movement amount of each drive piece,
Since the moving speed can be determined based on the inner diameter of each branch, a micromachine device in which the relative moving amount and the relative moving speed are set to desired values can be obtained. In addition, as compared with the case where a light source, an optical fiber, and a cylinder are provided for each driving piece, the overall configuration can be significantly simplified, and the overall size can be significantly reduced.

[0012]

BRIEF DESCRIPTION OF THE DRAWINGS FIG. FIG. 1 is a schematic central longitudinal sectional view showing one embodiment of an optical actuator device according to the present invention, wherein one end is connected to the other end of an optical fiber 2 optically coupled to a light source 1, and
The other end 3a of the cylindrical body 3 branched into two is attached,
In addition, a driving piece 4 for applying a driving force to a driving mechanism (not shown) is accommodated in the two branch portions 3b of the cylindrical body 3 so as to be movable in the axial direction. And optical fiber 2
The light-absorbing fluid 6 is accommodated in the space defined by the other end face, the cylindrical body 3 and the driving piece 4. In addition, an outflow preventing member 7 is provided so that the light-absorbing fluid 6 does not flow out through the gap between the driving piece 4 and the branch portion 3b. A restoring member 8 is provided for surely restoring the driving piece 4 when the light source 1 is not turned on. The driving piece 4
The operation unit which performs a predetermined operation by being driven by the controller is not shown.

As the light source 1, various light sources, for example,
YAG laser, Ar laser, He-Ne laser, Nd-
Although a YAG laser, a Ho-YAG laser, a semiconductor laser, or the like can be employed, it is preferable to select a laser that emits light having a wavelength with high absorption efficiency by the light absorbing fluid 6.
As the optical fiber 2, various types, for example, a glass-based optical fiber, a plastic-based optical fiber, and the like can be used. However, it is preferable to use a multi-mode type optical fiber having a pure silica core. Can be guided with high efficiency.

The cylinder 3 may be made of various materials, for example, synthetic resin, metal, and the like. Specifically, it is preferable to have a rigidity such that it is not easily deformed even by the expansion of the light-absorbing fluid 6, and therefore, for example, a thin SUS cylinder is used. The other end 3a of the tubular body 3 may be attached to the other end of the optical fiber 2 by, for example, an adhesive or a contracting force of the tubular body 3 itself. Further, a stopper mechanism (in FIG. 1, a cap capable of inserting a small-diameter shaft of the driving piece 4 forms a stopper mechanism) is provided as needed to prevent the driving piece 4 from coming off. Further, the branch shape of the branch portion 3b of the cylindrical body 3 can be appropriately determined according to the environment to which the micromachine device is applied. Specifically, for example, a radial branch shape, a branch shape in which at least the distal ends of the plurality of branch portions 3b are set in parallel with each other, and the like can be exemplified.

It is preferable that the driving piece 4 be made of a material that is lightweight and has a certain degree of compressive rigidity. A flange is formed at the end on the side in contact with the outflow prevention member 7, and other parts are formed. Is preferably formed in a small diameter rod shape. Further, as the material, a synthetic resin, a metal, or the like can be appropriately selected. Further, a ball bearing is mounted on the outer peripheral surface of the flange portion of the driving piece 4 so that the driving piece 4
It is preferable to make the movement of the object smooth.

As the light-absorbing fluid 6, various fluids can be used as long as they expand in volume when irradiated with light. Therefore, not only a fluid that is generally recognized as a light-absorbing fluid and can obtain a large thermal expansion by light irradiation for a short time, but also a thermal expansion that is generally recognized as a light-absorbing fluid is not recognized. Even a fluid can be adopted as the light absorbing fluid 6 in the present invention. Therefore, not only various gases and liquids but also air can be adopted as the light absorbing fluid. However, it is preferable to employ a fluid having a high absorptance for the wavelength of the light emitted from the light source 1, and the driving piece 4 can be moved by a sufficiently long distance by short-time light irradiation. That is, a sufficiently large driving force can be given. Specifically, the excitation light wavelength is 2.
When a 1 μm Ho-YAG laser is used as the light source 1, it is preferable to use water having a high absorption efficiency for the above wavelength as the light absorbing fluid 6. Further, when an arbitrary light source 1 and an arbitrary light absorbing fluid 6 are employed, it is preferable to mix a powder having a high light absorbing property such as a carbon powder. In this case, the color of the mixed powder is black. Is most preferably set to. Further, the size (inner diameter and length) of the space in which the light-absorbing fluid 6 is accommodated is appropriately set based on the outer diameter of the optical fiber 2, the required pressing force of the driving piece 4, and the like. For example, if the inner diameter is 3
The length is set to about 0 to 600 μm and the length is set to about 1 to 100 mm.

Various types of the outflow prevention member 7 are provided.
For example, a thin rubber film, a synthetic resin film, or the like can be used. Further, the outflow preventing member 7 only needs to be able to prevent the outflow of the light-absorbing fluid 6 from the gap between the cylindrical body 3 and the driving piece 4.
Any shape can be used as long as it can cover at least the gap. However, it is preferable to employ a bag capable of accommodating all of the light absorbing fluid 6, and it is possible to completely prevent the outflow of the light absorbing fluid 6. In this case, it is preferable to use a material having high elasticity, high pressure resistance, high heat resistance, and high light transmittance. In particular,
When a load of 10 gf is applied from the upper portion of a bag having a substantially cylindrical cross section in which the light absorbing fluid 6 is sealed, the width of the bag changes by about 2 to 5 times the original width and the load is changed. It is preferable that the resin has elasticity enough to return to the original shape immediately by removing the same, and that the desired properties including the elasticity and the like can be maintained in an environment of 50 ° C. or more. It preferably has heat resistance. However, with respect to heat resistance, it is more preferable to have heat resistance at 100 ° C. or higher to maintain the above desired characteristics in consideration of laser light irradiation. As for the pressure resistance, it is preferable to have as high a pressure resistance as possible within a range where the above-mentioned elasticity and heat resistance can be satisfied. Furthermore, since it is required to efficiently guide the light emitted from the optical fiber 2 to the light absorbing fluid 6,
It is preferable to employ a bag having the highest possible transparency. Examples of materials that can satisfy the above requirements include silicon, polyamide, polyethylene, polytetrafluoroethylene, polycarbonate, polyester, polystyrene, acetylcellulose, and latex. The thickness of the bag is set to about 5 to 100 μm. In order to obtain a sealed bag in which the light-absorbing fluid 6 is sealed, for example, the light-absorbing fluid 6 is sealed in a bag having one opening, and then the opening is closed by heat sealing or the like. Is adopted. Further, when the outflow prevention member 7 having the former configuration is employed, various materials can be employed without being limited to the above-described materials.

As the restoring member 8, an elastic body made of a coil spring, an air spring, rubber or the like can be adopted, but the restoring member 8 can be omitted as shown in FIG. . However, in this case, it is preferable that a part of the outflow prevention member 7 and a part of the driving piece 4 are integrated by an adhesive or the like. The operation of the optical actuator device having the above configuration is as follows.

When the light source 1 is turned on in a state in which the cylinder 3 and the operation unit (not shown) are guided to the work area by a predetermined method, light emitted from the light source 1 is transmitted through the optical fiber 2 to the light absorbing fluid 6. Can be irradiated. The light-absorbing fluid 6 expands when it is irradiated with light. However, since the other end faces of the cylindrical body 3 and the optical fiber 2 are prevented from expanding, the force caused by the expansion is applied to each branch 3b. Act on the flange portion of the driving piece 4 inserted in the optical fiber 2 to move the driving piece 4 in a direction away from the optical fiber 2. In this case, since the moving amount and moving speed of each driving piece 4 are determined based on the inner diameter of the corresponding branch portion 3b, the relative moving amount and relative moving speed of each driving piece 4 are set to desired values, and A desired operation can be performed by the operation unit. Also, in order to control the amount of movement of the driving piece 4,
When the light source 1 is continuously turned on, the amount of movement of the driving piece 4 can be accurately controlled by controlling the lighting duration time (the ratio of the lighting time when the light source 1 is turned on intermittently). it can. However, although it is impossible to control the movement amount of each driving piece 4, the relative movement amount
Since the relative speed is set to a desired value, no inconvenience occurs.

After the predetermined operation by the operating section is performed, the light source 1 may be turned off, and the light absorbing fluid contracts and the restoring force acts on the driving piece 4 by the restoring member 8. , The driving piece 4 is restored to the original position.
If the restoring member 8 is omitted, the time required for the driving piece 4 to be restored to the original position is slightly longer, but since the predetermined operation has been performed by the operating unit, it is not particularly inconvenient. No.

[0021]

Embodiment 2 FIG. 3 is a schematic central longitudinal sectional view showing another embodiment of the optical actuator device of the present invention. The only difference from the embodiment of FIG. 1 is that the outflow preventing member 7 is omitted. . Therefore, in this embodiment, the same operation as in the above embodiment can be achieved, and the outflow preventing member 7 can be provided.
Is omitted, the configuration can be simplified.

In this embodiment, it is impossible to mount a ball bearing as in the first embodiment. However, instead of the ball bearing, the inner surface of the cylindrical body 3 and the flange of the driving piece 4 are replaced. By forming a fine rough surface on at least one of the outer peripheral surfaces and holding the fluid on the rough surface, a movement smoothing action similar to that of a ball bearing can be achieved, and the outflow of the light-absorbing fluid can be achieved. A blocking effect can be achieved. In this case, it is preferable to use a liquid as the light-absorbing fluid. Since the light-absorbing fluid is held on a fine rough surface, it is necessary to specially prepare a fluid for holding the rough surface. Disappears.

[0023]

As described above, according to the first aspect of the present invention, the amount of movement of the plurality of driving pieces is accurately controlled by controlling the lighting duration or the ratio of the lighting time of the light source, and the relative movement of each driving piece is controlled. The amount can be set to a desired value, and the size can be significantly reduced as a whole as compared with the case where an actuator mechanism is employed. This has a unique effect that the workability of assembly can be improved.

[Brief description of the drawings]

FIG. 1 is a schematic central longitudinal sectional view showing one embodiment of an optical actuator device of the present invention.

FIG. 2 is a schematic central longitudinal sectional view showing a modified example of the optical actuator device of the present invention.

FIG. 3 is a schematic central longitudinal sectional view showing another embodiment of the optical actuator device of the present invention.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Light source 2 Optical fiber 3 Cylindrical body 3a The other end part 3b Branch part 4 Drive piece 6 Light absorbing fluid

────────────────────────────────────────────────── ─── Continuation of the front page (56) References JP-A-57-53721 (JP, A) JP-A-5-180148 (JP, A) (58) Fields investigated (Int. Cl. ⁶ , DB name) F15B 21/06 F15B 15/14

Claims (1)

(57) [Claims] 1. An optical fiber (2) having one end optically coupled to a light source (1) and the other end of a cylindrical body (3) having one end branched into a plurality. (3a) is attached, and the driving piece (4) is inserted into the plurality of branch portions (3b) of the cylindrical body (3) so as to be movable in the axial direction of the branch portion (3b). The other end face of the fiber (2) and the cylindrical body (3)
An optical actuator device characterized in that a light-absorbing fluid (6) is accommodated in a space defined by an inner surface of the first member and a driving piece (4).