JPH07238433A - Reversible cylindrical fabric having different diameters - Google Patents

Abstract

PURPOSE:To provide reversible cylindrical fabric having the diameter varied which is suitably used as a reinforcing material for the membranes in the air springs of a diaphragm type or air actuators, because reversing is smooth with high durability without fatigue failure. CONSTITUTION:In woven fabric of a cylindrical form, the lowered elongation warps 6 are arranged annularly in the axial direction of the cylinder all over the fabric length, while the lowered elongation wefts 7 are spirally woven into both ends 9, 10, the wefts 8 of covered yarn in which elastic yarn is covered with covering yarn of lowered elongation are spirally woven into the middle warps. At the same time, the diameter of the fabric is made larger in one fabric end 10 than that in the other 9, while, in the middle part 11, the diameter is almost equal to 9 on no loading, and is made almost equal to, or slightly smaller than the large one, when the weft 8 is fully stretched. The cylindrical woven fabric differing in diameter 5 is buried in a rubber tube of thick wall, and a cylindrical membrane is formed so that the end of the smaller diameter is fitted to the rod and the other end of larger diameter 10 is fitted to the outer shell body. Thus, a fluid pressure is applied between the rod and the outer shell body to make both of them slidable.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a reversible different-diameter tubular woven fabric, which relates to a different-diameter tubular woven fabric used as a reinforcing material for a membrane in a diaphragm type air spring, an air actuator or the like. Is.

[0002]

2. Description of the Related Art The film body is interposed between a rod and an outer shell body in a state of being folded inside and outside so that the folded portion moves when the rod and the outer shell body slide in the axial direction. By doing so, the rod and the outer shell are kept airtight while allowing the rod and the outer shell to slide.

A film body of this type is disclosed in JP-A-61-38.
The one described in Japanese Patent No. 238 is known. This product has a structure in which a rubber tube is reinforced with fibers only in the axial direction.

Further, Japanese Patent Publication No. 3-65254 discloses a film body in which a bias cloth is wound in a tubular shape and used as a reinforcing material.

[0005]

However, the fiber reinforced only in the axial direction of the film body is not reinforced in the circumferential direction, so that it tends to swell and tear in the radial direction due to the internal pressure.

Further, in the case of using the bias cloth, the reversal does not move smoothly because the overlapping portion is partially formed and the thickness is partially different.

Further, as shown in FIG. 4, a tubular fabric having a different diameter, which is woven in a tubular shape while changing the diameter according to the shape of the film body 1, can be used as the reinforcing material. When sliding 3 and 3, the diameter of the film body 1 cannot be changed, so that the folded-back portion 4 is sharply folded back as shown by the chain line in FIG.

Therefore, when the folded-back portion 4 moves, the folded-back state moves abruptly, so that the film body 1 is repeatedly subjected to abrupt bending and lacks durability.

The present invention has been made in view of the above circumstances, and is folded back by the internal pressure with a large radius of curvature in the folded portion 4, and is not subjected to sudden bending.
The purpose is to provide a film body 1 having excellent durability.

[0010]

SUMMARY OF THE INVENTION The present invention is a tubular woven fabric comprising a warp thread arranged in an annular shape and a weft thread spirally woven in the circumferential direction with respect to the warp thread. Is continuous over the entire length, and the weft yarns at both ends of the tubular fabric are made of low-elongation yarns, and the weft yarns in the central portion are made of low-elongation yarns around the elastic elastic core yarn. It is characterized in that it is composed of a covering yarn formed by winding a cover yarn, and the diameter of the tubular woven fabric changes in the longitudinal direction in the unloaded state.

In the present invention, one end of the tubular woven fabric has a diameter smaller than that of the other end, and the center portion has a diameter substantially equal to or smaller than the diameter of the one end in an unloaded state. Is preferred.

Further, it is preferable that the central portion has a diameter substantially equal to or smaller than the diameter of the other end portion when the weft cover thread is fully extended.

[0013]

Embodiments of the present invention will be described below with reference to the drawings. FIG. 1 shows a different-diameter tubular fabric 5 of the present invention. The different-diameter tubular fabric 5 includes warp yarns 6 arranged in an annular shape and extending in the axial direction, and circumferentially with respect to the warp yarns 6. The weft threads 7 and 8 woven in a spiral shape are woven in a tubular shape.

Thus, the warp yarn 6 of the tubular cloth 5 of different diameter is
A low elongation yarn is used, and the weft yarns 7 of both end portions 9 and 10 of the tubular fabric 5 having different diameters are also made of a low elongation yarn.

As shown in FIG. 2, the weft thread 8 in the central portion 11 is made of a stretchable elastic thread as a core thread 12, and a covering thread 13 having a low elongation is wound around the core thread 12. Is used.

Further, one end portion 9 of the different-diameter tubular fabric 5 has a small diameter and the other end portion 10 has a large diameter, and the central portion 1
It is preferable that 1 has a diameter substantially equal to or smaller than the diameter of the small-diameter end portion 9 in the unloaded state.

Then, the central portion 11 of the tubular fabric 5 having a different diameter is approximately the same as the diameter of the other end portion 10 when the cover yarn 13 of the weft yarn 8 is fully extended by the internal pressure.
Alternatively, the diameter is preferably smaller than that.

[0018]

The film body 1 is obtained by embedding the different-diameter tubular fabric 5 of the present invention within the thickness of the rubber tube. Then, as shown in FIG. 3, the film body 1 is fitted to the outside of the rod 2,
The small-diameter end 9 is attached to the rod 2, the large-diameter end 10 is folded back, and the end 10 is attached to the outer shell 3.
Install on.

When the rod 2 and the outer shell 3 are slid while the fluid pressure is applied between the rod 2 and the outer shell 3, the folded portion 4 of the film body 1 moves. Allow sliding of both.

Since the internal pressure acts on the portion folded back from the folding portion 4, the diameter of the weft yarn 8 can be expanded by extending the core yarn 12 of the weft yarn 8, as shown by the chain line in FIG. From the inside to the outside of the folded portion 4 of the film body 1, the film body 1 is bent with a large radius of curvature.

Therefore, when the folded-back portion 4 moves, the inner portion and the outer portion are reversed at the folded-back portion 4 having a large radius of curvature, so that the folded portion can be smoothly reversed without being subjected to sudden bending. .

Further, the weft thread 8 in the central portion is a stretchable core thread 12
Since the cover yarn 13 having a low elongation is wound around the core yarn 12,
Is extended and the cover thread 13 is in a fully extended state, the cover thread 13 bears the load and does not extend further, the film body 1 does not expand excessively, and the burst strength also increases. .

[0023]

According to the present invention, therefore, when the rod 2 and the outer shell 3 slide, the film body 1 can be smoothly inverted at the folded-back portion 4 to allow sliding. Since the film body 1 itself inverts along a large radius of curvature, the inversion is smooth.

Further, since the film body 1 does not undergo sharp bending at the folded-back portion 4, fatigue failure does not occur and durability is greatly improved.

As described above, the weft thread 8 in the central portion
Since the extension range of is limited, the cover thread 13 can bear the internal pressure, and the film body 1 in the outer portion does not excessively expand, and a high pressure can be applied.

Further, in the present invention, in the unloaded state,
Since the central portion 11 of the different-diameter tubular fabric 5 substantially matches the diameter of the small-diameter end portion 9 or has a diameter smaller than that, the central portion of the tubular body 5 when the film body 1 is fitted to the rod 2 is It is along the rod 2, and there is no possibility that the rod 2 and the film body 1 are displaced from each other due to the sliding of the rod 2 and the outer shell body 3, resulting in unnecessary behavior.

Even when the cover yarn 13 of the weft yarn 8 is fully extended, the diameter of the central portion 11 of the tubular fabric 5 with different diameters does not become larger than that of the end portion 10 having a large diameter, and the film body is largely outward. Since it does not swell, the air spring and the actuator can be made compact.

[Brief description of drawings]

FIG. 1 is a partially cutaway side view of an embodiment of a different-diameter tubular fabric 5 of the present invention.

FIG. 2 is an enlarged side view of the weft thread 8 in the central portion of the different-diameter tubular fabric 5.

FIG. 3 is a film body 1 using the different-diameter tubular fabric 5 of the present invention.
A central longitudinal cross-sectional view of the main part showing the usage state of

FIG. 4 shows a film body 1 using a conventional tubular fabric of different diameters 5,
Central longitudinal cross-sectional view of main parts showing usage

[Explanation of symbols]

 5 Cylindrical fabrics with different diameters 6 Warp yarns 7 Weft yarns at both ends 8 Weft yarns in the central portion 9 Small diameter end portions 10 Large diameter end portions 11 Central portion 12 Core yarns 13 Cover yarns

Claims (3)

[Claims] 1. A tubular fabric (5) comprising a warp thread (6) arranged in an annular shape and a weft thread (7, 8) woven spirally in the circumferential direction with respect to the warp thread (6). The warp yarn (6) is continuous over the entire length, the weft yarns (7) at both ends of the tubular fabric (5) are low elongation yarns, and the weft yarn (11) at the central portion (11) is 8) is a cover yarn (1) of low elongation yarn around a core yarn (12) of elastic yarn having elasticity.
3) A reversible tubular fabric of different diameter, comprising a covering yarn formed by winding 3), wherein the tubular fabric (5) changes in diameter in the longitudinal direction in the unloaded state. 2. The one end portion (9) of the tubular woven fabric (5) has a smaller diameter than the other end portion (10), and the central portion (11) has a diameter of the one end portion (9) in a non-loaded state. The reversible different-diameter tubular fabric according to claim 1, characterized in that the diameters are substantially the same or have a smaller diameter. 3. The central part (11) of the tubular fabric (5)
Is approximately equal to or smaller than the diameter of the other end portion (10) when the cover thread (13) of the weft thread (8) is fully extended.
Reversible different-diameter tubular fabric