JP4109352B2 - Multilayer structure connection method - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to a method for connecting a multilayer structure composed of a plurality of layers.
[0002]
[Prior art]
A multilayer structure such as a belt or a sheet in which a plurality of reinforcing layers having a rubber coating applied to a fiber layer such as canvas or cord are stacked and integrated is used for various purposes.
[0003]
As an example of using this multi-layer structure, rubber gates for pipelines used as sewer pipes, drainage pipes of rivers and canals, etc., and acting as valves (for example, Bridgestone Corporation's Expand Gate (trade name) )).
[0004]
As shown in FIG. 1, the rubber gate 100 for pipelines is used by being installed inside the pipeline 102.
[0005]
The rubber gate 100 for pipes is a bag body in which the outer peripheral portion of two rubber multilayer structures 104 is fixed to the inner wall of the pipe with a metal fitting 106, and the outer surface of the pipe is expanded by supplying air to the inside. The water flow is stopped by contacting the inner wall.
[0006]
As shown in FIG. 2, the multilayer structure 104 is bonded so that reinforcing layers 108 </ b> A to 108 </ b> C coated with rubber coating are stacked on a fiber layer 106 such as canvas or cord, and a thin cover rubber 110 is formed on the inner surface side. A thick cover rubber 112 is bonded to the side and integrated by high pressure pressing.
[0007]
As shown in FIG. 2, when a crack (penetration flaw) 114 occurs in the multilayer structure 104, conventionally, the repair has been performed by the following method.
[0008]
First, as shown in FIG. 3, the cover rubber 110, the reinforcing layers 108 </ b> A to 108 </ b> C, and steps are attached to each layer from the inner side (arrow IN direction side) to the outer side (arrow OUT direction side) around the crack 114. A part of the cover rubber 112 is removed using a cutter or the like, and a stepped recess 115 is formed.
[0009]
Next, a rubber pad 116 is bonded to a concave portion formed by the cover rubber 110 and the reinforcing layer 108A adjacent to the cover rubber 110 so that no gap is formed, and the end of the reinforcing layers 108B and 108C is projected to the outside. The repair reinforcing layer 118A and the reinforcing layer 118B are bonded so that there is no gap between them, and then the cover rubber for repair is placed on the outside so as to abut against the end of the cover rubber 112 of the multilayer structure 104. 120 is adhered, and a tape-like rubber 122 is adhered so as to cover a joint portion between the cover rubber 112 and the repair cover rubber 120 of the multilayer structure 104, and finally the shape shown in FIG.
[0010]
[Problems to be solved by the invention]
However, when a tension as shown by an arrow f in FIG. 4 is applied to the multilayer structure 104, stress concentrates on the abutting portion between the end portion of the layer and the end portion of the layer, so that the joint portion (repair portion) There is a problem that the strength is lower than that of the main body portion of the multilayer structure 104 and the fatigue property is poor, and this tendency is remarkable particularly when the modulus of the reinforcing layer is low.
[0011]
The present invention was made as a result of studying as a subject to solve such problems of the prior art, and an object of the present invention is to provide a method for connecting multilayer structures capable of increasing the strength of a joint portion. It is to provide.
[0012]
[Means for Solving the Problems]
The invention according to claim 1 is a connection method of a multilayer structure in which the end faces of the multilayer structure composed of a plurality of layers are connected to each other, each layer extending in an opening area toward one surface. A first stepped recess that is stepped every time is formed around the connection portion of the multilayer structure, and at least one first coupling layer is formed so as to cover all the stepped portions. Layers constituting the multilayer structure so as to fill the second stepped recesses formed in the first connection layer bonded to the stepped recesses and further bonded so as to cover all the stepped portions. A multi-layer structure connection method, wherein a plurality of second connection layers arranged along the line are adhered and stacked.
[0013]
The operation of the multilayer structure connecting method according to claim 1 will be described.
[0014]
In the connection method of the multilayer structure according to claim 1, first, the first stepped recess that is stepped for each layer in the direction in which the opening area increases toward one surface is centered on the connection portion of the multilayer structure. Formed as. That is, here, the layers are cut (deleted) so as to increase the cut area for each layer around the connection portion.
Next, at least one first connection layer is bonded along the inner wall surface of the first stepped recess so as to cover all the stepped portions. By bonding the first connection layer along the inner wall surface of the first stepped recess, a second stepped recess corresponding to the first stepped recess is formed in the first connection layer. Will be.
[0015]
Next, a plurality of second linking layers are bonded and stacked along the layers constituting the multilayer structure so as to fill the second stepped recesses, and the connection of the multilayer structures is thus completed.
[0016]
In the multilayer structure thus connected, the ends of the layers constituting the multilayer structure, or the ends of the layers constituting the multilayer structure and the ends of the first coupling layer and the second coupling layer The number of places where and are directly matched decreases.
[0017]
Where the ends of the layers directly abut each other, stress tends to concentrate when tension is applied to the multilayer structure, but in the multilayer structure connected so that the location decreases as described above, Stress concentration is relaxed.
[0018]
Furthermore, in the connection method of the multilayer structure according to the first aspect, the number of layers is increased by at least one in the connection portion, so that the strength is improved against the tension.
[0019]
The layer referred to here may be made of a plurality of materials such as canvas, cords or the like coated with rubber, or may be formed of a single material such as resin film or rubber.
According to a second aspect of the present invention, in the method for connecting multilayer structures according to the first aspect, the first coupling layer is formed so as to cover only the first stepped recess. It is said.
[0020]
DETAILED DESCRIPTION OF THE INVENTION
Hereinafter, an embodiment of the present invention will be described with reference to the drawings.
[0021]
As described in the prior art, the rubber gate 100 for pipes shown in FIG. 1 has reinforcing layers 108A to 108C formed by applying rubber coating to the fiber layer 106 such as canvas or cord shown in FIG. The multilayer structure 104 is used in which a thin cover rubber 110 is bonded to the inner surface side and a thick cover rubber 112 is bonded to the outer surface side and integrated by a high-pressure press.
[0022]
In the present embodiment, when a crack (penetration flaw) 114 occurs in the multilayer structure 104, the repair is performed by the following method.
[0023]
First, as shown in FIG. 5, the reinforcing layers 108B and 108C and the cover rubber 112 are stepped for each layer from the inside (arrow IN direction side) to the outside (arrow OUT direction side) centering on the crack 114. A part (the peripheral part of the crack 114) is deleted using a cutter or the like, and a part of the inner cover rubber 110 is also removed.
[0024]
Next, the thickness of the reinforcing layers 108A to 108C is the same as that of the reinforcing layers 108A to 108C so that no gap is formed in the stepped portion at the bottom of the stepped recess 124 formed by removing a part of the reinforcing layers 108B and 108C and the cover rubber 112. The reinforcing reinforcing layer 126 for repairing is bonded with an adhesive, and the adhesive 130 is embedded in the recessed portion 128 formed by removing a part of the cover rubber 110 on the opposite side. Use and glue. Note that the ends of the reinforcing layer 108A are also bonded using an adhesive.
[0025]
Since the repair reinforcing layer 126 has a constant thickness like the reinforcing layers 108 </ b> A to 108 </ b> C, the repair reinforcing layer 126 bonded to the stepped recess 124 has a stepped recess corresponding to the stepped recess 124. 131 will be formed.
[0026]
Next, the repair reinforcing layers 132 and 134 having the same thickness as the reinforcing layers 108A to 108C are bonded using an adhesive so as to fill the stepped recess 131 formed in the repair reinforcing layer 126. Also at this time, the repair reinforcing layer 126 and the repair reinforcing layers 132 and 134 are bonded so that no gap is generated.
[0027]
Thereafter, a repair cover rubber 136 formed in accordance with the shape of the recess remaining in the multilayer structure 104 is adhered using an adhesive so as to cover the joint portion between the cover rubber 112 and the repair cover rubber 136. A tape-like rubber 122 is bonded to the end to finally have a shape as shown in FIG.
[0028]
As the adhesive, it is preferable to use a rubber-based natural vulcanized adhesive having excellent adhesion between rubbers.
[0029]
According to the repair method of the present embodiment, since the repair reinforcing layer 126 is bonded so as to cover the end portion of the reinforcing layer of the multilayer structure 104, the end portions of the reinforcing layer are directly butted together and joined. The number is reduced.
[0030]
The portion where the ends of the reinforcing layer are directly abutted and joined is a portion where stress tends to concentrate when the tension f acts on the multilayer structure 104. Therefore, the concentration of stress is reduced by reducing the portion. Since the number of reinforcing layers in the joint portion is increased, the strength of the joint portion can be improved. Moreover, since the strength of the joint portion is improved, it is also resistant to fatigue.
[0031]
In the present embodiment, an example in which the crack 114 generated in the multilayer structure 104 is repaired is shown, but the present invention can also be applied to a case where the multilayer structures 104 are jointed.
[0032]
The present invention can also be applied to repair or joint cracks such as belts, rubber dams, and the like that are formed of a plurality of layers similar to the multilayer structure 104.
[0033]
【The invention's effect】
As described above, in the connection method of the multilayer structure of the present invention, the stress concentration point generated when tension is applied to the multilayer structure can be reduced in the connection part, and the strength against tension can be improved. It has the excellent effect of being able to.
[Brief description of the drawings]
FIG. 1 is a cross-sectional view of a rubber gate for pipelines to which a multilayer structure is applied.
FIG. 2 is a cross-sectional view of a multilayer structure.
FIG. 3 is an explanatory diagram illustrating a process of a conventional repair method for a multilayer structure.
FIG. 4 is a cross-sectional view of a multilayer structure repaired by a conventional repair method.
FIG. 5 is a cross-sectional view of the multilayer structure being repaired using the multilayer structure connection method of the present embodiment.
FIG. 6 is an explanatory diagram illustrating a process of a connection method for a multilayer structure according to the present embodiment.
FIG. 7 is a cross-sectional view of a multilayer structure repaired by the multilayer structure connection method of the present embodiment.
[Explanation of symbols]
104 Multilayer structure 108A Reinforcing layer (layer)
108B Reinforcement layer (layer)
108C Reinforcement layer (layer)
124 Stepped recess (first stepped recess)
126 Reinforcing layer (first connecting layer)
131 Stepped recess (second stepped recess)
132 Reinforcement layer (second tie layer)
134 Reinforcing layer (second connecting layer)

Claims (2)

A connection method for a multilayer structure in which the end faces of the multilayer structure composed of a plurality of layers are connected in a face-to-face state,
Forming a first stepped recess that is stepped for each layer in the direction in which the opening area increases toward one surface, with the connection portion of the multilayer structure as a center,
Adhering at least one first connecting layer to the first stepped recess so as to cover all the stepped portions;
Further, the first step is disposed along the layers constituting the multilayer structure so as to fill the second stepped recess formed in the first coupling layer bonded so as to cover all the stepped portions. A method for connecting multilayer structures, wherein a plurality of the two connection layers are bonded and stacked. 2. The method for connecting multilayer structures according to claim 1, wherein the first coupling layer is formed to cover only the first stepped recess.

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