JPH0680322B2 - Closure member for elastic contraction body - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION (Industrial field of use) The present invention relates to an a bag whose outer periphery is reinforced by a braided reinforcing structure and which expands and deforms by supplying and discharging a pressurized fluid to generate a contracting force in the axial direction. A type of elastic contraction closing member.

(Prior Art) An air bag type elastic contraction body that expands in the radial direction while contracting in the longitudinal direction by introducing a pressurized fluid is significantly lighter than a device using an electric motor or a hydraulic cylinder. In addition, it has many excellent features that conventional actuators do not have, such as smooth movement and easy control. As such an elastic contraction body, for example, the one shown in FIG. 5 is known from Japanese Patent Publication No. 52-40378. In FIG. 5, 1 is a tubular body, 2 is a braided reinforcing structure on the outer periphery thereof, 3 is a closing member at both ends, and 4 is a caulking cap.

For the tubular body 1, rubber or a rubber-like elastic material is useful in terms of air impermeability and flexibility, but a uniform material, for example, various plastic materials may be substituted.

The braided reinforcing structure 2 has such a braided structure as to reach a so-called static angle (54 ° 44 ′) at the time of maximum expansion due to filling of the internal pressure of the tubular body 1.
For example, aromatic polyamide fiber (Kevlar: trade name)
Also suitable are twisted or untwisted bundles of filaments such as ultrafine metal wires.

One of the closing members 3 is provided with a connecting hole 8 on at least one side, which communicates with an internal cavity 7 of the tubular body 1 through a hole 6 formed in the longitudinal direction thereof, and a fitting 9 is attached thereto. An operating pressure source (not shown), such as an air compressor, is connected to the fitting 9 by a pipe line including a flow control valve, and a control pressure is applied to the inner cavity 7 of the tubular body 1. The expansion of the assembly angle, that is, the pantograph movement brings about the expansion of the tubular body 1 and the contraction in the axial direction resulting therefrom, that is, the reduction of the distance between the connecting pin holes of the closing member 3.

(Problems to be solved by the invention) By the way, the air bag type elastic contraction body described above expands radially outwardly when a pressurized fluid is applied to its inner cavity, but at both ends thereof, Since the deformation of the tubular body and the braided reinforcing structure is constrained by the closing member 3 and the caulking cap 4 cooperating with these members, a rapid change in diameter occurs and a curved portion is generated near the closing member. Therefore, in this curved portion, the tension acting on each fiber constituting the braided reinforcing structure is different and uniform pantograph movement cannot be performed,
There is a problem that the energy of the pressurized fluid cannot be efficiently used for work. In addition, the braided reinforcing structure is apt to cause the braid to break, and as shown schematically in FIG. 6, the tubular body locally projects radially outward from the braided part in the vicinity of the closing member. There is a problem that the tubular body is easily damaged.

(Object of the Invention) The present invention has been made in view of such a problem, and an elastic contractor that can efficiently use the energy of a pressurized fluid without causing a sudden diameter change in the vicinity of the closing member. It is intended to provide a closure member for.

(Means for Solving the Problems) In order to solve the above-mentioned problems, the elastic contraction body closing member of the present invention particularly has at least an enlarged portion having a gradually increasing diameter and a diameter equal to the maximum diameter of the enlarged portion. Of the braided reinforcement structure in the columnar part of the tubular body before the application of the pressurized fluid from the center diameter of the braided reinforcement structure before applying the pressurized fluid. Expand.

(Operation) According to this closing member, since the center diameter of the braided reinforcing structure in the cylindrical portion is made larger than that of the braided reinforcing structure in the central portion of the tubular body before applying the pressurized fluid, the pressurized fluid is applied. The influence of the curved portion in the vicinity of each closing member of the elastic contraction body when expanded and deformed is reduced, and the energy can be efficiently used. Moreover, since the tubular body and the braided reinforcing structure are enlarged along the enlarged portion whose diameter is gradually increased, the axis line of each closing member is substantially surrounded when the closing members are inserted into the openings at both ends of the tubular body. It becomes easy to align them in a straight line, and it is possible to prevent the fatigue life and contraction force of the elastic contraction body from being reduced due to the deviation of these axes.

(Example) With reference to drawings, the closure member for elastic contraction bodies of the present invention is explained in full detail below.

FIG. 1 (a) is a view showing an embodiment of the closing member of the present invention in a partial cross section, and the same parts as those shown in FIG. 5 are designated by the same reference numerals. The closing member 10 of the present embodiment,
It is made of a metal material or a plastic material that is not deformed or damaged even when it receives a compressive force in its radial direction, that is, even when the caulking cap is caulked.
In the axial direction of the tubular body 2, there is provided an enlarged portion 11 having a gradually increasing diameter, and a cylindrical portion 12 located adjacent to the enlarged portion and having an outer diameter substantially equal to the maximum diameter of the enlarged portion.

The enlarged portion 11 has a cylindrical shape having a diameter equal to or slightly larger than the inner diameter of the tubular body in order to facilitate the insertion of the tubular body 1 shown in phantom in FIG. 1A into this enlarged portion. The protruding portion 13 is provided at the end on the tubular body side. It should be noted that the tubular body may be mounted more easily by chamfering the edge of the protrusion 13.

On the other hand, the columnar portion 12 is a columnar sealing portion 14 that is adjacent to the enlarged portion 11 sequentially in the axial direction of the closing member 10,
The first groove 15a, the first protrusion 16a, the hook portion 17 having a diameter substantially equal to that of the sealing portion 14, the second groove 15b, and the second protrusion 16b.
And with. These first and second grooves 15a and 16b are for accommodating an adhesive agent, and the adhesive agent accommodated in the first groove 15a is the first along the enlarged portion 11 and the sealing portion 14. The opening edge of the tubular body 1 extending to the protrusion 16a is set to the second groove 15b.
The adhesive material accommodated in the adhesive member adheres to the closing member 10 the edges of the braided reinforcing structure 2 that extend outwardly in the axial direction of the tubular body to the second protrusions 16b. As the adhesive, for example, if the closing member is integrally formed of mild steel, a rigid adhesion between the closing member and the tubular body made of rubber or a rubber-like elastic body is secured. For example, an alpha acrylate adhesive is used. However, it is appropriately selected according to each material. Further, by making these grooves annular, not only can a certain amount of adhesive be reliably accommodated, but also the width can be maintained substantially constant with respect to each closing member, so that in each product. The variation in performance can be reduced. As described above, the first and second protrusions 16a and 16b contact the respective end faces of the tubular body 1 and the braided reinforcing structure 2 to define their insertion lengths, and the caulking cap is caulked. At this time, the first protrusion 16a more firmly clamps the braided reinforcing structure 2 together with the crimping cap, and the second protrusion functions as a guide member. FIG. 1 (b) is an enlarged view showing how the closing member having such a structure is engaged with the tubular body and the braided reinforcing structure. Note that reference numeral 18 is an example of a screw portion as a connecting means for connecting the closing member 10 to a fixed wall or the like.

As described above, in this embodiment, a groove or a protrusion is provided in a cylindrical portion that is substantially equal to the maximum diameter of the enlarged portion 11, and the braided reinforcing structure that covers the tubular body and the outer periphery thereof is configured to be difficult to come out of the closing member. The present invention is not limited to this, and a cylinder having a cylindrical outer surface is applied, and an adhesive is applied to the whole or a part of the outer surface to adhere the tubular body and the braided reinforcing structure to the cylindrical portion, and they are joined with a caulking cap. May be.

The diameter of the cylindrical portion of such a closing member is variously changed, with respect to the center diameter of the braided reinforcing structure in the central portion of the tubular body,
The elastic contraction body using the closure member of the present invention with respect to the ratio of the center diameter of the braided reinforcing structure in the cylindrical portion, that is, the expansion ratio K, and the contraction force generated in the conventional elastic contraction body when the pressurized fluid is applied. The ratio of the contraction force generated in the skin, that is, the relationship with the contraction force ratio was obtained by an experiment. An example of this result is shown in FIG. The elastic contraction body used at this time had a tubular body inner diameter of 12
φ, the outer shape is made of synthetic rubber with a diameter of 14φ, while the braided reinforcement structure is made by braiding twisted polyester fibers.
The contraction rate of the elastic contraction body is used as a parameter, and the value is 0%,
5%. Ten%. Various changes were made to 15% and 20%.

As is clear from this figure, the enlargement ratio K is 1.10 to 1.5,
It is understood that the shrinkage force can be improved by more preferably selecting the range of 1.10 to 1.30. In particular, when the contraction rate of the elastic contraction body is set to 20%, the expansion ratio K =
It can be seen that at 1.3, the contraction force is 1.5 times or more that of the elastic contraction body using the conventional closing member, and the contraction force greatly increases. Even if the expansion ratio K is set to be larger than 1.30, the contraction force can be similarly increased, but if the ratio is large, it becomes difficult to insert the tubular body and the braided reinforcing structure into the closing member. Therefore, the expansion ratio is 1.10.
It is advantageous to select in the range of ~ 1.30.

3 and 4 are views showing other embodiments of the present invention.

The embodiment shown in FIG. 3 has the same structure as the embodiment shown in FIG. 1 (a), and the end portion of the second annular projection 16b is extended outward in the axial direction thereof. The support portion 18 is formed, and the support member can be used to fix the closing member to the column, the fixed wall, or the like.

The embodiment shown in FIG. 4 is a closing member capable of supplying and discharging pressurized fluid to and from the internal cavity 7 of the tubular body 1.
And a connection hole 8 which is open to the hole 6 and in which a fitting 9 can be attached. Further, reference numeral 19 is a connecting pin hole provided in the closing member.

The respective closing members of the present invention shown above are attached to the tubular body and the braided reinforcing structure by a dedicated wearing tool or manually.

(Effects of the Invention) As described in detail above, according to the closure member of the present invention, the diameter near the openings at both ends of the tubular body whose outer periphery is covered by the braided reinforcement structure is determined by the braided reinforcement in the central portion of the tubular body. By adopting a structure in which the pressure is held larger than the center diameter of the structure and sealed, it is possible to prevent a sudden diameter change in the vicinity of the closing member when a pressurized fluid is applied. Can reduce energy loss and efficiently convert the energy into work. Moreover, the enlarged part is
Since one end has a shape that is approximately equal to the inner diameter of the tubular member and its diameter gradually increases, not only is it easy to insert the tubular member into the closing member, but also the axes of the respective closing members inserted into both ends of the tubular member are mutually Since there is no deviation, an elastic contraction body having excellent durability is obtained.

[Brief description of drawings]

FIG. 1 (a) is a front view showing a partial cross section of the closing member of the present invention, and FIG. 1 (b) shows the closing member shown in FIG. FIG. 2 is a cross-sectional view showing a state of being inserted into an opening of a covered tubular body, FIG. 2 is a view showing a performance curve of an elastic contraction body using the closing member of the present invention, and FIGS. FIGS. 5 and 6 are partial cross-sectional front views and external views showing other embodiments of the present invention, and FIGS. 5 and 6 are partial cross-sectional views of a conventional air bag type elastic contraction body and the application of pressurized fluid. It is a figure when it did. DESCRIPTION OF SYMBOLS 1 ... Tubular body, 2 ... Braided reinforcement structure 3, 10 ... Closing member, 4 ... Caulking cap 7 ... Internal cavity, 8 ... Connection hole 11 ... Enlarged part, 12 ... Cylindrical part 13 ... Projection part, 14 ... Sealing part 15a, 15b ... Groove, 16a, 16b ... Protrusion 17 ... Locking portion, 18 ... Screw portion 19 ... Connecting pin hole

Claims (1)

[Claims] 1. A closure member for an elastic contraction body, which is inserted into an opening of a tubular body of rubber or a rubber-like elastic material whose outer periphery is reinforced by a braided reinforcing structure of high-tensile fibers, the tubular body being a tubular body. Of the braided reinforcing structure in the cylindrical portion, at least the enlarged portion of which the diameter gradually increases outwardly in the axial direction and the cylindrical portion having the diameter equal to the maximum diameter of the enlarged portion. A closing member for an elastic contraction body, characterized in that it is expanded from the center diameter of the braided reinforcing structure in the central portion of the tubular body before application.