JP7410564B2 - Actuator manufacturing method and actuator - Google Patents

Description

The present invention relates to an actuator, and particularly to an actuator that can be expanded and contracted by supplying pressure to the inside thereof, and a method for manufacturing the actuator.

Conventionally, as shown in Patent Document 1, an example of an actuator that can be used as an artificial muscle is one in which rubber is formed into a cylindrical shape with fibers as a restraining material inserted therein, and both ends of the rubber are sealed. It has been known. In this actuator, by supplying pressure such as air from the outside into the sealed internal space, the rubber expands in the radial direction and contracts in the axial direction due to the restraint of the inserted fibers. Therefore, it functions as an excellent actuator with a predetermined stretching force.

Japanese Patent Application Publication No. 2011-137516

However, the above-mentioned method of inserting fibers into rubber involves a step of aligning multiple fibers along the axis to form a sheet, and a step of winding the sheet-shaped fibers around latex molded into a tube. This requires a process of integrating the fibers by applying latex to the outer periphery of the integrated tube, making it difficult to ensure the uniformity of the fibers and to achieve continuous production.

The present invention has been made in view of the conventional problems, and provides a method of manufacturing an actuator, etc., in which restraining materials can be arranged uniformly and with high productivity.

One aspect of solving the above problem is to provide a method for manufacturing an actuator including an elastic cylindrical body that has a plurality of restraining members extending in the axial direction and that can be expanded and contracted by supplying and discharging pressure to the inside. a step of forming a cylindrical fiber group by connecting the restraining materials along the circumferential direction of the elastic cylindrical body with a restricting material that cannot be separated from each other, and a step of fixing the elastic material on the surface of the fiber group; The embodiment includes the following.
According to this aspect, the elastic material is fixed to the cylindrical fiber group in which the plurality of restraining materials cannot be separated from each other along the circumferential direction of the elastic cylindrical body by the regulating material. In contrast, the restraining materials can be arranged uniformly, and these steps can be performed continuously.
In another embodiment, the method further includes a step of releasing the connection by the regulating material after fixing the elastic material.
According to this aspect, the elastic cylindrical body expands smoothly in the radial direction by releasing the connection of the regulating member. Further, in the releasing step, it is preferable that the regulating material be melted, dissolved in water, broken, stretched, or a combination thereof.
Moreover, the actuator obtained by the above manufacturing method has a plurality of restraining members extending in the axial direction and a restricting member that prevents the plurality of restraining members from separating from each other along the circumferential direction, and has pressure supply to the inside. The actuator is equipped with an elastic cylindrical body that can be expanded and contracted by evacuation, and the restricting member is configured to break or expand due to the expansion and expansion caused by the supply of pressure to the elastic cylindrical body, and the plurality of restraint members can be released. .
Note that the above-mentioned summaries of each invention do not list all the necessary features of the present invention, and subcombinations of these feature groups may also constitute an invention.

FIG. 3 is a diagram schematically showing an actuator. It is a sectional view of an elastic cylindrical body. It is a figure showing a part of manufacturing process of an actuator.

FIG. 1 is a diagram showing the basic configuration of an actuator 1 according to an embodiment. As shown in FIG. 1, the actuator 1 includes an elastic cylindrical body 10 (hereinafter referred to as the cylindrical body 10) as an elastic part, and a sealing body that tightly closes openings 10a and 10b at both ends of the cylindrical body 10. 20a; 20b. Although details will be described later, the cylindrical body 10 is made of rubber having a predetermined thickness and is formed into a cylindrical shape, and has openings 10a and 10b at both ends in the axial direction. Note that natural latex rubber, silicone rubber, etc. are suitable as the rubber.

As shown in FIG. 2, inside the rubber constituting the cylindrical body 10, a plurality of fibers 15 as a restraining material extending parallel to each other along the axial direction are arranged at an approximately uniform density along the circumferential direction. Interpolated. Note that although this example shows an example in which the fibers 15 are embedded and inserted into the rubber, they may also be partially exposed on the rubber surface or arranged along the rubber surface. good. The fibers 15 may be, for example, carbon, nylon, polyester, aramid, or other fibers, and more preferably carbon or aramid fibers with low elongation. By subjecting these fibers to a suitable primer treatment or surface oxidation treatment, their adhesion to rubber can be sufficiently improved and integration can be achieved. Further, the fiber 15 can be used in any form such as filament, yarn (spun yarn and filament yarn), strand, etc. Furthermore, untwisted fiber that is converged without twisting, or these fibers can be used. It is also possible to use fibers made by twisting a plurality of fibers. Although it depends on the type of fiber, two or more types of fibers made of different materials or fibers with different shapes may be combined.

The openings 10a and 10b of the cylindrical body 10 are respectively closed by sealing bodies 20a and 20b. The openings 10a; 10b and the sealing bodies 20a; 20b are respectively fastened by rings 12a; 12d that firmly fasten the outer peripheries. Further, rings 12b and 12c are interposed between the rings 12a and 12d at equal intervals in the axial direction and cannot be removed.

By closing the openings 10a and 10b of the cylindrical body 10 with the sealing bodies 20a and 20b, a chamber C is formed inside the cylindrical body 10 to which pressure of fluid such as air can be supplied. Further, although not shown, a pressure supply hole communicating with the chamber C is formed in the sealing body 20a, 20b or one of them, and by connecting a tube or the like to the pressure supply hole, an air compressor, etc. It is possible to supply and discharge pressure from the outside.

As shown in FIG. 1(b), when pressure such as air is supplied into the chamber C of the cylindrical body 10, the cylindrical body 10 expands in the radial direction and expands along the axial direction. As a result of the axial extension being restricted by the plurality of fibers 15, the fibers 15 contract in the axial direction. At this time, since the four rings 12a to 12d are arranged in the axial direction of the cylindrical body 10, the three parts located between these rings become the expansion parts 14a to 14c. Note that the number of rings and their presence/absence can be set arbitrarily. In this way, the actuator 1 according to the present example can expand and contract in the axial direction by supplying and discharging pressure.

Next, a method for manufacturing the actuator 1 having the above structure will be described. FIG. 3A is a schematic diagram showing a cylindrical fiber group 30 made up of fibers 15 inserted into the cylindrical body 10. The cylindrical fiber group 30 according to this example is continuously formed along the axial direction by a predetermined loom K. As shown in the figure, the cylindrical fiber group 30 includes a plurality of fibers 15 as warp threads extending along the axial direction, and a circle of the cylindrical body 10 that is woven into each fiber 15 and perpendicular to the fibers 15. The regulating thread 17 as a weft extending along the circumferential direction forms a cylindrical shape with openings at both ends.

The regulating threads 17 are arranged at predetermined intervals along the extending direction of the fibers 15, and serve to regulate and connect the fibers 15 so that they cannot be separated. Furthermore, the regulating thread 17 is preferably made of a material that can regulate and disconnect the fibers 15 from each other when the actuator 1 is used. For example, fibers that can be melted or dissolved in water by heat, water, or other solvents, fibers that have low strength and break when the cylindrical body 10 expands, fibers that have high extensibility and can restrict and connect the fibers 15 by expansion. Included are releasable fibers.

That is, the regulating thread 17 regulates and connects the fibers 15 before fixing the rubber in the next step, and can release the regulation and coupling of the fibers 15 after fixing the rubber or when the cylindrical body 10 expands. It is a fiber. By creating the cylindrical fiber group 30 in advance using such regulating threads 17, the fibers 15 before the rubber is fixed are arranged uniformly along the circumferential direction and are aligned along the axial direction. They can maintain a state in which they extend parallel to each other.

Next, as shown in FIG. 3(b), a cylindrical core material (not shown) is inserted into the cylindrical fiber group 30 that is continuously drawn out from the knitting machine, and the cylindrical fiber group 30 that is continuously formed is pulled out. while transferring to the rubber fixing process. As shown in the figure, in the rubber fixing step, natural latex rubber or silicone rubber is passed through a storage tank 40 filled with the rubber, or a certain amount of rubber is sprayed onto the outer peripheral surface of the cylindrical fiber group 30 by a predetermined spraying means. Apply rubber to a thickness of . Through this process, rubber is impregnated through the mesh of the cylindrical fiber group 30, and a rubber layer of a predetermined thickness having the cylindrical fiber group 30 on the surface or inside the mesh is formed. In addition, if it is necessary to fix the rubber on the inner peripheral surface side from the viewpoint of durability, it is possible to fix the inner peripheral surface by continuously turning over the cylindrical fiber group 30 from one end of the core material toward the other end. The surface may be exposed as the outer peripheral surface and the above fixing step may be performed again. After the fixing step is completed, vulcanization is performed to integrate the rubber and the cylindrical fiber group 30, so that the cylindrical fiber group 30 in which the fibers 15 are uniformly arranged and the rubber are integrated. A cylindrical body 10 can be obtained. Thereafter, by cutting the integrated cylindrical body 10 into a predetermined length, a cylindrical body 10 having a desired predetermined length and applicable to the actuator 1 can be obtained.

In addition, if the regulating thread 17 is a heat-fusible fiber, regulation and connection are released by heat during vulcanization or a separate heat treatment process, and if it is a water-soluble fiber, it is coated with rubber or separated separately. Regulation and connection are released by the liquid treatment process. Furthermore, in the case of breakable fibers or highly extensible fibers, the restriction and connection will be released by expansion of the cylindrical body 10 during the first operation of the actuator 1 (cylindrical body 10).
In other words, if the actuator 1 that is regulated and uncoupled by the regulating thread 17 is considered as a final product, the cylindrical body 10 that is regulated and coupled by the regulating thread 17, or the actuator 1 equipped with this, is It can be conceptualized as an intermediate product.

As described above, according to the above embodiment, it is possible to obtain the actuator 1 in which the fibers 15 extending in the axial direction are aligned in a uniform state with respect to the cylindrical body 10, and the stability of the expansion and contraction operation is improved. can be improved. Moreover, since the cylindrical fiber group 30 can be continuously molded and continuously transferred to the rubber fixing process, the manufacturing efficiency of the cylindrical body 10 and the actuator 1 can be dramatically improved.

1 actuator (artificial muscle), 10 cylindrical body, 12a to 12d ring,
15 fiber, 17 regulating thread, 20a; 20b sealing body, 30 cylindrical fiber group, 40 storage tank

Claims (4)

A method for manufacturing an actuator comprising an elastic cylindrical body having a plurality of restraining members extending in the axial direction and expandable and contractible by supplying and discharging pressure to the inside, the method comprising:
forming a cylindrical fiber group by connecting the plurality of restraining materials along the circumferential direction of the elastic cylindrical body with a restricting material that makes them impossible to separate from each other;
fixing an elastic material on the surface of the fiber group;
A method of manufacturing an actuator, comprising: releasing the connection by the regulating material after fixing the elastic material;
The method of manufacturing an actuator according to claim 1, further comprising: 3. The actuator manufacturing method according to claim 2, wherein in the step of releasing the regulating material, the connection is released by melting, breaking, elongating the regulating material, or a combination thereof. a plurality of restraints extending in the axial direction ;
An actuator including a regulating member that prevents the plurality of restraining members from being separated from each other along the circumferential direction, and an elastic cylindrical body that can be expanded and contracted by supplying and discharging pressure to the inside,
The actuator is characterized in that the restricting member is broken or elongated by expansion due to the supply of pressure to the elastic cylindrical body, and the plurality of restricting members can be released.

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