JPWO2019102799A1 - Actuator - Google Patents

Abstract

The actuator of the present invention includes a fibrous polymer material that is rotationally driven around a fiber axis by heating, and both ends of the fibrous polymer material are fixed by a tensile stress T (MPa). (MPa) has the relationship of the following formula (1) with Young's modulus E (MPa) in the fiber axis direction of the fibrous polymer material. 0.011 x E ≤ T ≤ 0.023 x E ... (1)

Description

The present invention relates to an actuator.
The present application claims priority based on Japanese Patent Application No. 2017-223548 filed in Japan on November 21, 2017, the contents of which are incorporated herein by reference.

With the advent of an aging society in developed countries, the development of robotics, and the shift to intellectual activities of humankind, the motorization of various articles is required, and various actuators have been proposed. For example, Patent Document 1 discloses that a reversible electric thermal twisting operation and a pulling operation have been demonstrated by an actuator containing a polymer fiber in which a twist is inserted in a coiled shape or a non-coiled shape.

The non-coiled twisted polymer fiber contained in the actuator inserts the twist into a high-strength, highly chain-oriented precursor polymer fiber that is single-filament or multifilament to a level that does not produce coiling. Is formed by

The coiled polymer fiber contained in the actuator is either twisted into the precursor polymer fiber until coiling occurs, or twisted to a level that does not generate coiling into the precursor polymer fiber. Is then formed by inserting the coiling in the same or opposite direction into the first inserted twist.

Japanese Unexamined Patent Publication No. 2016-42783

As described above, Patent Document 1 discloses a polymer actuator that gives a torsional operation (that is, rotational drive), but the drive stability of the actuator may decrease depending on the temperature environment for driving the actuator. ..

The present invention has been made in view of the above circumstances, and an object of the present invention is to provide an actuator having excellent drive stability in an environment in a wide temperature range.

As a result of examination by the present inventors in order to achieve the above object, the following findings were obtained. The fibrous polymer material constituting the polymer actuator has different temperature-mechanical properties depending on the material, and the mechanical strength (for example, Young's modulus) generally decreases in a temperature environment exceeding the glass transition temperature (Tg). .. As a result, when the actuator is driven at a temperature higher than the glass transition temperature (Tg) of the fibrous polymer material (for example, 80 ° C if the glass transition temperature (Tg) is 47 ° C), the actuator is attempted. It was found that the drive stability of the That is, it has been found that when the actuator is driven at the above-mentioned high temperature, a decrease in Young's modulus leads to a decrease in fixed tension (that is, tensile stress), and a decrease in fixed tension adversely affects the driving stability of the actuator. Further, even if the tension at room temperature is too high, there is a concern that the fibrous polymer material in the actuator may break.

The actuator according to the first aspect of the present invention based on such findings is as follows.
(1) A fibrous polymer material that is rotationally driven around a fiber shaft by heating and a fixing means for fixing both ends of the fibrous polymer material are provided.
Both ends of the fibrous polymer material are fixed by the fixing means with a tensile stress T (MPa), and the tensile stress T (MPa) is the Young's modulus E (Young's modulus E in the fiber axis direction of the fibrous polymer material). An actuator having the relationship of the following formula (1) with MPa).
0.011 x E ≤ T ≤ 0.023 x E ... (1)

(2) The actuator according to (1) above, further comprising a heating means.
(3) In the above (1) or (2), the polymer constituting the fibrous polymer material includes a polymer having a regular polymer orientation non-parallel to the fiber axis of the fibrous polymer material. The actuator described.
(4) The actuator according to (3) above, wherein the fibrous polymer material is twisted.

The actuator of the present invention can exhibit excellent drive stability in an environment over a wide temperature range.

It is the schematic which shows the actuator which concerns on one Embodiment of this invention. It is the schematic which shows the main part of the actuator which concerns on one Embodiment of this invention. It is the schematic which shows an example of the manufacturing method of the actuator which concerns on one Embodiment of this invention. It is the schematic which shows the measuring method of the power of an actuator. It is the schematic which shows the measuring method of the power of an actuator. It is a graph which shows an example of the result of the operation stability evaluation of the actuator of an Example. It is a graph which shows an example of the result of the operation stability evaluation of the actuator of the comparative example.

FIG. 1 is a schematic view showing an actuator 1 according to an embodiment of the present invention.
The actuator 1 includes a fibrous polymer material 10 that is rotationally driven around a fiber axis by heating, and fixing means 20 and 21 that fix both ends of the fibrous polymer material 10, and the fibrous polymer material 10 Both ends are fixed by the fixing means 20 and 21 with a tensile stress T (MPa), and the tensile stress T (MPa) is between the Young's modulus E (MPa) in the fiber axial direction of the fibrous polymer material 10. Has the relationship of the following formula (1).

0.011 x E ≤ T ≤ 0.023 x E ... (1)

The above formula (1) may be at any temperature regardless of the glass transition temperature (Tg) of the fibrous polymer material, and is any one of Tg-22 ° C. or higher and Tg or lower of the fibrous polymer material. It may be at a temperature, at Tg-22 ° C. of the fibrous polymer material, or at 25 ° C.
By setting the tensile stress T when fixing the fibrous polymer material 10 by the fixing means 20 and 21 as the condition of the equation (1), the actuator 1 of the embodiment has stable driveability in an environment of a wide temperature range. Can be obtained.

In the actuator of the embodiment, the fibrous polymer material 10 is preferably twisted. The twisted (ie, twisted) fibrous polymeric material 10 can usually be obtained by inserting the twist in a non-coiled manner while maintaining a linear shape without spiraling. Further, the twisted fibrous polymer material 10 is twisted at a stage of forming a fibrous shape in a general fiber spinning and twisting process, that is, production of a fibrous polymer material. It may be twisted in the process. Since the fibrous polymer material 10 is twisted, the actuator that can be driven by heating can be driven even more efficiently.

When an untreated fibrous polymer material is manufactured in advance and then the fibrous polymer material is twisted by a method of inserting a twist, the fibrous polymer material 10 is, for example, a monofilament of nylon 6 or 6 having a diameter of 500 μm. In an environment of 25 ° C., for example, when a moderate tensile stress of 1 × 10 ^-3 to 1 × 10 ⁻² times the Young's modulus of nylon 6 or 6 monofilaments is applied and twisted so as not to cause coiling, A non-coiled twisted monofilament that has been rotated up to about 400 to 600 times per meter can be obtained.

Further, as the fibrous polymer material 10, for example, a nylon 6,6 monofilament having a diameter of 250 μm is used in an environment of 25 ° C., and the Young's modulus of the nylon 6,6 monofilament is 1 × 10 ^-3 to 1 × ^10-2. When twisted by applying twice an appropriate tensile stress so as not to cause coiling, a non-coiled twisted monofilament rotated up to about 850 to 1150 times per meter can be obtained. If the monofilaments of nylons 6 and 6 are twisted beyond this rotation speed, coiling may occur or the nylon may break. In addition, when a tensile stress exceeding 1 × ^10-2 times the Young's modulus of the filament is applied, snails (rolls) tend to occur and the filament tends to break.

In this way, a fiber composed of a polymer having a glass transition temperature higher than 25 ° C. is twisted by applying an appropriate tensile stress in a temperature environment below the glass transition temperature of the polymer (for example, 25 ° C.). Then, a non-coiled twisted monofilament twisted to the state immediately before coiling at that temperature (25 ° C.) can be obtained.

Further, when twisted at a temperature higher than 25 ° C., for example, a temperature higher than the glass transition temperature of the polymer constituting the untreated fibrous polymer material to be twisted, the polymer is rotated to a higher number of revolutions. However, there are cases where it can be twisted without causing coiling or breaking of the fibrous polymer material.

In the fibrous polymer material 10 twisted in a temperature environment equal to or lower than the glass transition temperature of the fibrous polymer material 10, in order to suppress the action of untwisting, the temperature is equal to or higher than the glass transition temperature of the polymer. It is preferable to perform residual stress relaxation treatment such as leaving it in the environment of the above for a certain period of time.
In the above, the acquisition of the twisted monofilament has been illustrated as the fibrous polymer material 10, but the fibrous polymer material 10 may be a twisted multifilament.

As shown in Examples described later, at room temperature (25 ° C.), the twisted monofilament (nylon 6, 6), which is the fibrous polymer material 10, has the relationship of the above formula (1). By fixing with a tensile stress T of 30 MPa or more and 50 MPa or less, stable rotational driveability can be maintained in an environment in a wide temperature range from room temperature (25 ° C) to 80 ° C, and an actuator with heat resistance can be provided. can get. The polymer actuator having the relation of the formula (1) using the twisted monofilament of nylons 6 and 6 as the fibrous polymer material is stable in a high temperature environment of 80 ° C. without impairing the stability of the driveability at room temperature. Demonstrate the driving performance.

Further, when the tensile stress T is higher than the Young's modulus E in the fiber axial direction of the fibrous polymer material 10, the output of the actuator (for example, the power Wr) tends to decrease. The tensile stress T is 0.023 × E or less, preferably 0.022 × E or less, more preferably 0.021 × E or less, and particularly preferably 0.020 × E or less. preferable.

Further, when the tensile stress T is low with respect to the Young's modulus E in the fiber axial direction of the fibrous polymer material 10, the driving stability of the actuator tends to decrease. The tensile stress T is 0.011 × E or more, preferably 0.012 × E or more, and more preferably 0.013 × E or more.

In the twisted (twisted) fibrous polymer material, the polymer constituting the fibrous polymer material has a regular polymer orientation that is non-parallel to the fiber axis of the fibrous polymer material. It may include things. It is generally known that a fibrous polymer material exhibits high anisotropy in structure and physical properties in the fiber axis direction and the direction perpendicular to the fiber axis direction due to the orientation of the polymer chains. This is because the polymer chains are oriented parallel to the fiber axis direction and easily form a crystal structure. The polymer constituting the fibrous polymer material preferably contains a polymer having a regular polymer orientation non-parallel to the fiber axis of the fibrous polymer material. The fact that the polymer constituting the fibrous polymer material contains a polymer having a regular polymer orientation that is not parallel to the fiber axis is one means of imparting a rotational driving function to the fibrous polymer material. is there. By twisting the fibrous polymer material, the polymers constituting the fibrous polymer material can be obliquely oriented along the fiber axis, and if necessary, annealing can be performed to bring about the above state. Can be fixed.
The fact that the polymers constituting the fibrous polymer material include those having a regular orientation non-parallel to the fiber axis is determined by small-angle X-ray scattering analysis and wide-angle X-ray diffraction analysis of the fibrous polymer material. Can be identified.

The actuator of the embodiment can be suitably driven at a temperature near the glass transition temperature (Tg) when a fibrous polymer material having a predetermined glass transition temperature (Tg) is used as a driving source, and is of the formula. Since it has the relationship (1), it exhibits excellent drive stability in a wide temperature environment including a temperature near the glass transition temperature (Tg). Therefore, for example, by using nylon 6 having a glass transition temperature (Tg) of 45 ° C. or nylon 6 or 6 having a glass transition temperature (Tg) of 47 ° C. as the fibrous polymer material, the drivability at around room temperature is not impaired, and the temperature is about 80 ° C. The actuator can be an actuator having excellent drive stability in a high temperature environment.

As the type of polymer constituting the fibrous polymer material, a linear polymer is preferable from the viewpoint of promoting crystallization of the polymer. Here, the linear polymer means a polymer whose main chain does not contain a cyclic structure. Examples of the linear polymer include low-density polyethylene, high-density polyethylene, polyolefins such as polypropylene, nylon 6, nylons 6,6 and the like, polytetrafluoroethylene, polychlorotrifluoroethylene, polyvinylidene fluoride, polyvinylidene fluoride, etc. Among fluororesins such as perfluoroalkoxy alkane resin, acrylic resins, urethane resins, etc., those having no cyclic structure in the main chain can be mentioned.
The fibrous polymer material may be a fiber made of the polymer material.
In the actuator of the embodiment, the glass transition temperature (Tg) of the polymer constituting the fibrous polymer material is preferably higher than 25 ° C., and the glass transition temperature (Tg) of the polymer is 40 ° C. or higher. Is preferable. The upper limit of the glass transition temperature (Tg) of the polymer is preferably 160 ° C. or lower, more preferably 90 ° C. or lower, and even more preferably 60 ° C. or lower. For example, the types of polymers include nylon such as nylon 6 (Tg: 45 ° C.) and nylon 6,6 (Tg: 47 ° C.), acrylic resin such as polymethylmethacrylate (Tg: 100 ° C.), and polyethylene terephthalate (Tg). : 80 ° C.) and other polyester resins, polycarbonate (Tg: 145 ° C.), polyvinyl chloride (Tg: 82 ° C.), polycarbonate (Tg: 150 ° C.), polyetheretherketone (Tg: 143 ° C.) and the like. Examples of the type of polymer having a glass transition temperature (Tg) of 25 ° C. or lower include polyethylene (Tg: −120 ° C.) and polypropylene (Tg: −20 ° C.).

In the actuator of the embodiment, for example, in the case of an actuator using nylons 6 and 6 having a glass transition temperature (Tg) of 47 ° C. as a fibrous polymer material, the driveability near room temperature is not impaired and the temperature is about 80 ° C. It is possible to obtain an actuator having excellent drive stability in a wide temperature range including a high temperature environment. For example, an actuator using polyethylene having a glass transition temperature (Tg) of −120 ° C. as a fibrous polymer material can be an actuator having excellent drive stability in a wide temperature range including around −120 ° C. .. For example, by using a polyetheretherketone having a glass transition temperature (Tg) of 143 ° C. as a fibrous polymer material, an actuator having excellent drive stability can be obtained in a wide temperature range including around 143 ° C.

As described above, the actuator of the embodiment can be an actuator having excellent drive stability in a wide temperature range of Tg ± 40 ° C. including the glass transition temperature (Tg) of the fibrous polymer material. Considering the usage environment of the actuator, the glass transition temperature of the fibrous polymer material (from the viewpoint that the room temperature is included in the temperature range with a high probability of increasing the stability of the actuator drive and the fibrous polymer material is excellent in versatility. Tg) is particularly preferably above 25 ° C and below 60 ° C.

The polymer constituting the fibrous polymer material is preferably crystalline. The crystallinity of the polymer in the fibrous polymer material is preferably 50% or more, and more preferably 55% to 90%. When the crystallinity is in such a range, the anisotropy of the molecular orientation is high, and it becomes easy to make the effect as an actuator excellent.

In the actuator of the embodiment, the fibrous polymer material may include monofilament fibers, may be composed of monofilament fibers, may contain multifilament fibers, or may be from multifilament fibers. It may be.
The fibrous polymer material may be a twisted monofilament fiber, or may be a twisted monofilament fiber until just before coiling occurs, that is, just before hump occurs.

The actuator of the embodiment includes fixing means 20 and 21 for fixing both ends of the fibrous polymer material 10. The fixing means 20 and 21 are not limited as long as both ends of the fibrous polymer material 10 can be fixed with a predetermined tensile stress T. It may be a simple chuck (that is, a fixing jig) capable of fixing the length of the fibrous polymer material 10 to a constant length, or it may be a fixing means provided with a spring capable of adjusting the tensile stress T.

In the actuator of the embodiment, the fibrous polymer material 10 is rotationally driven around the fiber shaft by heating. The actuator of the embodiment may be provided with heating means, or may be rotationally driven around the fiber axis in response to an external environmental temperature without providing heating means.

The heating means included in the actuator of the embodiment is preferably a conductor that is in direct contact with the fibrous polymer material. The heating means is preferably a linear conductor wound around a fibrous polymer material with a predetermined gap spirally provided. The fibrous polymer material can be heated by applying a voltage to the conductor.
2, the fibrous polymer material 10 with a diameter D _10, is a schematic diagram showing an example in which the linear conductor 11 of diameter D ₁₁ is wound with a predetermined gap distance I helically.

Examples of the linear conductor 11 include a metal wire and a thread of carbon nanotubes. Preferred metal wires include tungsten wire, stainless wire, copper wire and the like.

The diameter _{D 10} of the fibrous polymeric material 10, 0.01 mm _<be a _{D 10} ≦ 40mm, 0.05mm _<be a _{D 10 ≦ 10mm, 0.1mm <D} 10 ≦ 1mm met You may.

Further, although the cross sections of the fibrous polymer material 10 and the linear conductor 11 are described on the assumption that they are circular, they may be substantially circular or substantially elliptical. It may have a flat shape. At that time, the major axis of the substantially circular, substantially elliptical or flat shape can be understood by substituting the circular diameter D ₁₁ or D ₁₀ (that is, in terms of Haywood diameter).

In order to set the electric resistance per length of the actuator 1 in a suitable range, the diameter D ₁₀ of the fibrous polymer material 10, the diameter D _{11 of} the linear conductor ₁₁ , and the pitch (I + D ₁₁ ) of the linear conductor ₁₁ Can be designed as appropriate. The diameter _{D 10} of the fibrous polymeric material 10, for example, when it is 0.1 mm _{<D 10} ≦ 1 mm, the diameter _{D 11} of the linear conductors 11 is preferably _{1μm ≦ D 11 ≦ 1000μm, 5μm} ≦ D 11 ≦ 500 μm is more preferable, and 10 μm ≦ D ₁₁ ≦ 100 μm is particularly preferable.

The diameter _{D 10} of the fibrous polymeric material 10, the relationship between the diameter _{D 11} of the linear conductors 11, preferably _{0.001 ≦ D 11 / D 10 <} 2, 0.005 ≦ D 11 / D 10 ≦ 1.0 is more preferable, and 0.01 ≦ D ₁₁ / D ₁₀ ≦ 0.5 is particularly preferable.

The relationship between the diameter D ₁₁ of the linear conductor ₁₁ and the distance I between the conductors of the linear conductor ₁₁ is preferably 0.01 ≦ I / D ₁₁ ≦ 10, and 0.05 ≦ I / D ₁₁ ≦ 5. Is more preferable, and 0.1 ≦ I / D ₁₁ ≦ 3 is particularly preferable.

The angle θ formed by the linear conductor 11 and the fibrous polymer material 10 is 0 ° <θ ≦ 90 °, preferably 30 ° ≦ θ ≦ 90 °, and more preferably 45 ° ≦ θ ≦ 75 °.

The linear conductor 11 is preferably fixed to the fibrous polymer material 10. It is preferable that the linear conductor 11 is spirally wound around the fibrous polymer material 10 and is adhesively fixed. Even if an adhesive is applied to the surface of the fibrous polymer material 10 around which the linear conductor 11 is wound, dried and cured to fix the linear conductor 11 on the surface 10 of the fibrous polymer material. Often, an adhesive is applied to the surface of the fibrous polymer material 10 in advance, and then the linear conductor 11 is wound on the adhesive layer on the surface of the fibrous polymer material 10 and dried / cured. The linear conductor 11 may be fixed on the surface of the fibrous polymer material 10.

In the embodiment in which the linear conductor 11 is spirally wound around the fibrous polymer material 10 and fixed by adhesion, the linear conductor 11 may be completely coated with the resin cured product of the adhesive, and the wire The resin cured product of the adhesive may be filled in the adjacent gaps of the spiral structure of the linear conductor 11, and a part of the linear conductor 11 may be exposed.

Since the linear conductor 11 is spirally wound around the fibrous polymer material 10 and adhered and fixed, the fixed position of the linear conductor 11 on the surface of the fibrous polymer material 10 is displaced. Easy to prevent.

An example of the method for manufacturing the actuator of the present invention will be described with reference to FIG. First, one end of the twisted monofilament fibrous polymer material 10 is stopped by the fixing means 20, and then the weight 40 is lowered to the other end of the fibrous polymer material 10. If the Young's modulus E of the twisted monofilament is measured in advance, the tensile stress T can be adjusted so as to have the relationship of the equation (1) by adjusting the weight of the weight 40. Further, the fibrous polymer material 10 is provided with the fibrous polymer material 10 and the fixing means 20 and 21 for fixing both ends of the fibrous polymer material 10 by stopping the fibrous polymer material 10 with the fixing means 21. Both ends of the 10 are fixed by the fixing means 20 and 21, and an actuator having the relationship of the formula (1) can be obtained.

Further, for example, a power transmission means 30 such as a stainless plate is provided in the center of the fibrous polymer material 10 fixed by the fixing means 20 and 21, and an object to be given motion is connected to one end or both ends of the stainless plate. As a result, the actuator functions as a power source. In this structure, the fibrous polymer material 10 is heated with respect to the power transmission means 30 by heating the half portion of the fibrous polymer material 10 on the fixing means 20 side in the range between the fixing means 20 and 21. Rotational drive around 10 fiber axes can be provided. Further, by heating the half portion of the fibrous polymer material 10 on the fixing means 21 side in the above range, the power transmission means 30 is reversed with respect to the fiber axis of the fibrous polymer material 10. Rotational drive can be given.

Hereinafter, the present invention will be described in more detail with reference to specific examples. However, the present invention is not limited to the examples shown below.

[Evaluation of Young's modulus of fibrous polymer material]
Twisted monofilaments (diameter 0.5 mm, number of twists 500 times / m) obtained in Examples and Comparative Examples were collected and subjected to a test length of 10 cm in a tensile tester with a constant temperature bath (Tensile tester 5581 manufactured by INSTRON). I installed it at. The constant temperature bath was kept at 25 ° C., 40 ° C., and 80 ° C., respectively, and the filament was attached and allowed to stand for 5 minutes or more before performing a tensile test. The tensile speed was 10 mm / min, and Young's modulus was calculated from the linear region of the obtained stress-strain curve.

[Evaluation of actuator operation stability]
Two stainless steel plates having a width of 4 mm, a length of 4 cm, and a thickness of 1 mm are fixed to the center (a portion 4 cm from the end) of the monofilament with a thin wire in the heat-responsive actuators obtained in Examples and Comparative Examples. (See Fig. 1). The total weight of this stainless steel plate was 6 g. In an environment of 25 ° C, a DC voltage of 5 V is applied to a part of half the length from the fixed part of one end of the monofilament with a thin wire to the central plate to cause rotational movement, and the central stainless plate. Was rotated. When the horizontal state of the stainless steel plate is set to the initial angle, the DC power is turned off when it is rotated by +20 degrees, and immediately after that, the half length part from the end fixing part of the other monofilament with a thin wire to the central stainless steel plate. Similarly, a DC voltage of 5 V was applied, and the rotation in the opposite direction was continued until the stainless plate reached -20 degrees. The same operation is repeated 60 times, the time t during which the motion is occurring in each rotation direction (“half cycle time”) t is measured for each cycle, and the relative standard deviation (RSD) of the half cycle time t is calculated. We compared and evaluated by. A similar operation test was performed at 40 ° C. and 80 ° C., and the relative standard deviation (RSD) of the half cycle time t was calculated for each temperature condition. Regarding the relative standard deviation (RSD), those below 5% were evaluated as "good", and those above 5% were evaluated as "bad".

[Measurement of actuator power]
A method of measuring the power of the actuator will be described with reference to FIGS. 4 and 5. A stainless steel plate having a length of 40 mm, a width of 7 mm, a thickness of 1 mm, and a weight of 2 g, which is a power transmission means 30, is used as a midpoint of a filament with a fine wire, which is a fibrous polymer material 10 of an actuator obtained in Examples and Comparative Examples. Was attached so as to intersect the filament with a thin wire at a right angle. As shown in FIG. 4, this measuring actuator is installed on the installation jigs 70 and 71 so that the filament with fine wire and the stainless plate are both horizontal, and are attached to both ends of the stainless plate which is the power transmission means 30. Nylon threads 50 and 51 having a diameter of 0.1 mm, which are so thin that the weight is negligible, were bonded. Next, a pulley 61 and a pulley 60 with an angle meter were installed above both ends of the stainless steel plate as shown in FIG. The positions of the pulley 61 and the pulley 60 with an angle meter are the positions where the nylon threads 50 and 51 extend vertically to reach the point of contact between the pulley 61 and the pulley 60 with an angle meter. The diameters of the pulley 61 and the pulley 60 with an angle meter were both 10 mm. Then, a 7 g weight 41 was attached to the tip of the nylon thread 50 that hangs down from the pulley 60 with an angle meter and is not connected to the stainless steel plate at a position 15 cm below the contact point with the pulley 60 with an angle meter. On the other hand, a 5 g weight 42 was attached to the tip of the nylon thread 51 hanging from the pulley 61 without an angle meter on the side not connected to the stainless steel plate.

Next, in an environment of 25 ° C., the installation jigs 70 and 71 are removed, and the stainless plate which is the central power transmission means 30 from the fixed portion of one end of the monofilament with a fine wire which is the fibrous polymer material 10. When a DC voltage of 12 V was applied for 2 seconds to the portion of half the length up to, the monofilament with a thin wire was rotationally driven and a 7 g weight 41 was suspended as shown in FIG. 5 (a). Subsequently, when a DC voltage of 12 V is applied for 2 seconds to the portion of the opposite half length of the monofilament with a thin wire, the monofilament with a thin wire is rotationally driven to drive a weight of 7 g, as shown in FIG. 5 (b). 41 was lifted. This was set as one cycle, and the work of lifting 2 g, which is the difference in weight between the weights on both sides, was repeated for 50 cycles. In this one cycle, the amount of movement d (mm) of the weight for 2 seconds to lift the weight difference of 2 g is calculated from the angle of the angle meter, and the power Wr is calculated from the following formula (2) using the value, and 50 cycles. Was calculated.
Wr (μJ / sec)
= 2 (g) ÷ 1000 × 9.8 × d (mm) ÷ 1000 × 10 ⁶ ÷ 2 (seconds)
= 9.8 × d (μJ / sec) ・ ・ ・ (2)

[Example 1]
A monofilament (manufactured by Toray Monofilament Co., Ltd.) made of nylon 6,6 (Tg: 47 ° C.) having a diameter of 0.5 mm is twisted under the conditions of a load of 400 g and a number of twists of 500 times / m, and annealing is performed at 180 ° C. for 40 minutes. This was performed to obtain a twisted monofilament. When the Young's modulus of the twisted monofilament was measured by the above evaluation method, the Young's modulus at 25 ° C. was 2.27 GPa. The Young's modulus E of nylon 6 and 6 monofilaments at 25 ° C. before twisting was 3.02 GPa, the Young's modulus E at 40 ° C. after twisting was 1.43 GPa, and the Young's modulus E at 80 ° C. was 0.95 GPa. Met.

Next, a fine tungsten wire having a diameter of 0.03 mm was wound around the twisted monofilament to serve as a heating means. The winding pitch of the tungsten thin wire (the sum of the width of one thin wire of one roll and the distance between the thin wire and the adjacent thin wire) was set to 0.12 mm.
The obtained filament with fine wires (that is, the fibrous polymer material 10) is collected, and one chuck (that is, fixing) of a jig provided with two chucks at a distance of 5 mm from one end. It was fixed to the means 20) (see FIG. 3). Then, the other end of the filament with fine wire is passed through another chuck (that is, fixing means 21) and connected to a weight 40 of 600 g, and the tension equal to the gravity applied to the weight 40 is the filament with fine wire. It was made to be applied to. Then, in that state, the lower chuck (that is, the fixing means 21) is closed and fixed to tension the filament with a fine wire at 600 gf (600 g ÷ 1000 × 9.8 ÷ ((0.25 mm ÷ 1000) ² × π) ÷. It was fixed at 10 ⁶ ≈ 30 MPa). The length of the portion stretched between the chucks of the filament with fine wire was 7 cm. In this way, a heat-responsive actuator for evaluation of operational stability was obtained. Further, in the same procedure, a heat-responsive actuator for measuring the power was obtained by setting the length of the portion stretched between the chucks of the filament with fine wires to 10 cm.

Table 1 shows the results of measuring the power by the above method for the heat-responsive actuator for measuring the power of Example 1. FIG. 6 and Table show the results of evaluating the operational stability of the heat-responsive actuator for evaluating the operational stability of Example 1 under the respective temperature environments of 25 ° C., 40 ° C., and 80 ° C. by the above method. Shown in 1.

[Example 2]
A heat-responsive actuator was obtained in the same manner as in Example 1 except that the mass of the weight 40 was changed and the tension for fixing the filament with a thin wire was set to 800 gf (about 40 MPa). Table 1 shows the results of measuring the power by the above method for the heat-responsive actuator for measuring the power of Example 2. Table 1 shows the results of evaluating the operational stability of the heat-responsive actuator for evaluating the operational stability of Example 2 under the respective temperature environments of 25 ° C., 40 ° C., and 80 ° C. by the above method. ..

[Example 3]
A heat-responsive actuator was obtained in the same manner as in Example 1 except that the mass of the weight 40 was changed and the tension for fixing the filament with a thin wire was set to 1000 gf (about 50 MPa). Table 1 shows the results of measuring the power by the above method for the heat-responsive actuator for measuring the power of Example 3. Table 1 shows the results of evaluating the operational stability of the heat-responsive actuator for evaluating the operational stability of Example 3 under the respective temperature environments of 25 ° C., 40 ° C., and 80 ° C. by the above method. ..

[Comparative Example 1]
A heat-responsive actuator was obtained in the same manner as in Example 1 except that the mass of the weight 40 was changed and the tension for fixing the filament with a thin wire was set to 400 gf (about 20 MPa). Table 1 shows the results of measuring the power by the above method for the heat-responsive actuator for measuring the power of Comparative Example 1. FIG. 7 and Table show the results of evaluating the operation stability of the heat-responsive actuator for the evaluation of the operation stability of Comparative Example 1 by the above method under each temperature environment of 25 ° C., 40 ° C. and 80 ° C. Shown in 1.

It was found that the heat-responsive actuators for measuring the power in Examples 1 to 3 and Comparative Example 1 all functioned at a power of 9 μJ / s or more.

When the operation stability of the heat-responsive actuators of Examples 1 to 3 and Comparative Example 1 for evaluation of operation stability was evaluated by the above method, both of the evaluations of 25 ° C. and 40 ° C. were "good". Was the judgment. Then, in the heating response type actuators of Examples 1 to 3, the judgment of the operation stability evaluation was "good" even at a high temperature of 80 ° C., but in the heating response type actuator of Comparative Example 1, at a high temperature of 80 ° C. , The judgment of the operation stability evaluation was a "bad" result.

By setting the tensile stress T when fixing the fibrous polymer material 10 by the fixing means 20 and 21 as the condition of the equation (1), the actuator 1 obtains stable driveability in an environment in a wide temperature range. It turns out that it can be done.

Each configuration and a combination thereof in each embodiment are examples, and the configurations can be added, omitted, replaced, and other changes are possible without departing from the spirit of the present invention. Moreover, the present invention is not limited to each embodiment, but is limited only to the scope of claims.

The actuator of the present invention can be used as an actuator for rotationally driving around a fiber shaft by heating in various articles for motorization.

1 ... Actuator, 10 ... Fibrous polymer material, 11 ... Linear conductor, 20, 21 ... Fixing means, 30 ... Power transmission means, 40, 41, 42 ... Weight, 50, 51 ... Nylon thread, 60 ... Slider with angle meter, 61 ... Slider, 70, 71 ... Installation jig, I ... Adjacent line of spiral structure of linear conductor Gap spacing between conductive conductors, D ₁₀ ... Diameter of fibrous polymer material, D ₁₁ ... Diameter of linear conductor, T ... Tension stress on fibrous polymer material by fixing means, E: Young's modulus of fibrous polymer material, d: Movement amount of weight

Claims (4)

It is provided with a fibrous polymer material that is rotationally driven around a fiber shaft by heating and a fixing means for fixing both ends of the fibrous polymer material.
Both ends of the fibrous polymer material are fixed by the fixing means with a tensile stress T (MPa), and the tensile stress T (MPa) is the Young's modulus E (Young's modulus E in the fiber axis direction of the fibrous polymer material). An actuator having the relationship of the following formula (1) with MPa).
0.011 x E ≤ T ≤ 0.023 x E ... (1) The actuator according to claim 1, further comprising a heating means. The actuator according to claim 1 or 2, wherein the polymer constituting the fibrous polymer material has a regular polymer orientation that is non-parallel to the fiber axis of the fibrous polymer material. The actuator according to claim 3, wherein the fibrous polymer material is twisted.

Images