JP2015009903A - Belt for pipe conveyor - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a belt for pipe conveyor keeping an adequate tubular shape when the belt is rounded.SOLUTION: A belt 1 for pipe conveyor is provided with a core body 2, a cover rubber 3 including the core body 2, a conveyance face side-reinforcing layer 4a provided at the side of a belt conveyance face A of the core body 2 in the cover rubber 3, and a rear face side-reinforcing layer 4b provided at the side of a belt rear face B of the core body 2 in the cover rubber 3. The belt is characterized in that the rear face side reaction force at the time when deforming the rear face side-reinforcing layer 4b by a prescribed amount in a belt width direction is larger than the conveyance face side reaction force at the time when deforming the conveyance face side-reinforcing layer 4a by the prescribed amount in the belt width direction.

Description

  The present invention relates to a pipe conveyor belt.

  Conventionally, as a belt conveyor suitable for the conveyance of powder particles and the like that can suppress the spillage and scattering of the conveyed product, the endless belt that circulates is rounded into a cylindrical shape in most of the traveling path, and the conveyed product is belted Pipe conveyors are known that are wrapped in and continuously conveyed.

  Here, the pipe conveyor presses the belt from the back side with a shape-retaining roller arranged so as to surround the belt for the pipe conveyor, rounds it into a cylindrical shape, and places the conveyed product in the space inside it for conveyance However, when the belt is rolled into a cylindrical shape, the upper portion of the rolled belt (the outer portion in the width direction of the belt) supported the upper portion of the belt due to its own weight or bending of the belt. Away from the belt, the belt may be crushed. If the transported object is transported in such a state, the transported object may not be effectively spilled or scattered, or may not be transported while securing an internal volume for placing the transported object. Accordingly, various pipe conveyor belts having an appropriate cylindrical shape, that is, rigidity capable of maintaining a state in which the belt is in contact with the shape-retaining roller surrounding the belt when the shape-retaining roller is rolled into a cylindrical shape have been proposed. (For example, patent document 1).

JP 2001-253519 A

  As shown in the above-mentioned Patent Document 1, for example, in a cover rubber, a core body made of a steel cord and the like, a canvas made of an organic fiber, etc., embedded along the longitudinal direction of the belt, are embedded. In the case of the belt for pipe conveyors, when the belt is rolled with a shape-retaining roller, the cylindrical shape may not be sufficiently retained.

  An object of the present invention is to solve such problems of the prior art, and an object of the present invention is to provide a pipe conveyor belt that can maintain an appropriate cylindrical shape when the belt is rolled. It is to provide.

The belt for a pipe conveyor of the present invention includes a core body, a cover rubber, a transport surface side reinforcing layer provided on the belt transport surface side with respect to the core body in the cover rubber, and the core in the cover rubber. A back side reinforcing layer provided on the back side of the belt with respect to the body, the back side reaction force when the back side reinforcing layer is deformed by a predetermined amount in the belt width direction. It is larger than the reaction force on the conveying surface side when the surface side reinforcing layer is deformed by the predetermined amount in the belt width direction.
According to the present invention, the back side reaction force of the back side reinforcing layer is made larger than the transport side reaction force of the carrying surface side reinforcing layer. Compared to the case where the forces are equal, the belt is positioned on the back surface side of the belt, and the rigidity when the belt is rolled can be increased, so that an appropriate cylindrical shape can be maintained.

In the present invention, the term “tension-compression neutral shaft” refers to a boundary between a region receiving compression input and a region receiving tensile input when the belt is pressed from the back side and rolled into a cylindrical shape in a pipe conveyor belt. The belt region closer to the conveying surface than the neutral shaft receives a compression input, and the belt region closer to the rear surface than the neutral shaft receives a tensile input.
Further, in the present invention, “reaction force when the reinforcing layer is deformed by a predetermined amount in the belt width direction” means that deformation (distortion) caused by applying a load in the direction of the belt width when the reinforcing layer is embedded in the belt. The reaction force when the reinforcing layer is deformed by a predetermined amount within the elastic range that returns to its original shape when the load is removed. Specifically, a test piece of a strip-shaped reinforcing layer having a width of 30 mm was prepared and left in a constant temperature and humidity room at 25 ° C. and 20 to 40% RH for one week, followed by a chuck interval of 250 mm and a tensile speed. The ss curve (stress-strain curve) is measured by pulling in the direction corresponding to the belt width direction under the condition of 25 mm / min, and each reinforcement layer has a strain of 2 to 5% in the ss curve. The value (N) obtained by multiplying the stress at the time of occurrence by the cross-sectional area of the test piece.
Furthermore, the reinforcing layer used for the above test piece should be the one after vulcanization treatment, and when there are multiple cord reinforcing plies, which will be described later, etc., measure them together. And
“Belt conveying surface” or “conveying surface” refers to the surface on the side where the object is placed / conveyed, in the thickness direction of the belt, and “belt back surface” or “back surface”. Of the two surfaces in the thickness direction of the belt, the surface opposite to the belt conveying surface is meant.

Here, in the belt for a pipe conveyor of the present invention, the transport surface side reinforcing layer and the back surface side reinforcing layer are each composed of a cord reinforcing ply composed of one or more polyester cords, and constitute the back surface side reinforcing layer. The cord reinforcing ply is formed by juxtaposing the weft yarns made of the polyester cord in the belt width direction in parallel in the belt longitudinal direction via the warp yarns extending in the belt longitudinal direction, and the parallel density of the weft yarns in the belt longitudinal direction is It is preferable that the parallel density in the belt width direction is larger. According to this, the neutral axis of the tension-compression of the pipe conveyor belt can be located more effectively on the back surface side of the belt, thereby maintaining a proper cylindrical shape more fully when the belt is rolled. Can be made.
In the present invention, “parallel density” refers to the number of cords per unit distance measured along the direction in which wefts or warps are aligned.
In the present invention, the “cord reinforcing ply” refers to a material in which a large number of cords made of organic fiber cords or metal cords are coated with a reinforcing rubber.

  According to this invention, when conveying a conveyed product, the belt for pipe conveyors which can hold | maintain an appropriate cylindrical shape can be provided.

It is sectional drawing along the width direction of the belt for pipe conveyors which shows typical embodiment of the belt for pipe conveyors of this invention. The partial perspective view which shows the interdigital structure (a), the plain weave structure (b), and the straight warp structure (c) as an illustration of the structure of the cord reinforcement ply embed | buried in the belt for pipe conveyors concerning embodiment of this invention It is.

Embodiments of the present invention will be described in detail below with reference to the drawings.
FIG. 1 shows a state in which a pipe conveyor belt 1 according to an embodiment of the present invention (hereinafter, “pipe conveyor belt” is also referred to as a “belt”) is flattened without placing a conveyed product. It is sectional drawing which follows a belt width direction.

  Here, the belt 1 for the pipe conveyor is stretched between a driving pulley and a driven pulley of the belt conveyor apparatus, and a conveyed product, for example, a powder or the like is placed on the conveying surface A side of the belt 1. The belt 1 is rounded into a cylindrical shape in most of the traveling path and continuously sent out in the traveling direction to prevent a spilled or scattered object while transporting a conveyed object for a short distance or a long distance. It is used for Although not shown, a shape-retaining roller that is disposed so as to surround the belt 1 and presses the belt 1 from the back surface B side is used to round the pipe conveyor belt 1 into a cylindrical shape.

  The belt 1 has an endless ring shape and is formed in a substantially flat plate shape as viewed in the belt width direction. As shown in FIG. 1, the core body 2, a cover rubber 3 containing the core body 2, and a cover With respect to the core body of the rubber 3, the transport surface side reinforcing layer 4 a inside the transport surface side cover rubber portion 3 a on the transport surface A side on which the transport object is placed, and the core body of the cover rubber 3. A back surface side reinforcing layer 4b is provided inside the back surface side cover rubber portion 3b on the back surface B side. Note that the thickness of the transport surface side cover rubber portion 3a and the back surface side cover rubber portion 3b is such that the upper surface cover rubber portion 3a is susceptible to wear and the like by transporting the transported object, as shown in FIG. The thickness of the transport surface side cover rubber portion 3a is thicker than that of the back surface side cover rubber portion 3b, but these thicknesses can be reversed.

  As shown in FIG. 1, a plurality of core bodies 2 are embedded in the belt 1, and the core bodies 2 are arranged along the belt longitudinal direction at substantially equal intervals in the belt width direction. Yes. Examples of the core 2 include a steel cord, an aramid cord, a carbon cord, and a copper cord. In the embodiment shown in FIG. 1, the core 2 is used from the viewpoint of increasing the strength of the pipe conveyor belt 1. Is made of steel cord.

  Furthermore, in the belt 1 for a pipe conveyor, the transport surface side reinforcing layer 4a and the back surface side reinforcing layer 4b disposed inside the transport surface side cover rubber portion 3a and the back surface cover rubber portion 3b are each provided with at least one layer of transport. It consists of a surface side cord reinforcement ply 5a and at least one back surface side cord reinforcement ply 5b. Further, the core 2 described above ensures the strength in the belt longitudinal direction, whereas the transport surface side reinforcing layer 4a and the back surface side reinforcing layer 4b ensure the strength in the belt width direction. In addition, in the place shown in FIG. 1, the conveyance surface side reinforcement layer 4a and the back surface side reinforcement layer 4b are each comprised by the cord reinforcement plies 5a and 5b of one layer.

In such a belt 1 for a pipe conveyor, when the belt 1 is rolled into a cylindrical shape, in a cross-sectional view in the belt width direction, the belt 1 receives a compression input on the conveyance surface A side from the tension-compression neutral axis NA. The located portion exerts a strong reaction force against the compression input, and therefore gives the belt 1 rigidity capable of maintaining its cylindrical shape. Therefore, in the pipe conveyor belt 1 of the present invention, as shown in FIG. 1, the reaction force on the back surface side when the back surface side reinforcing layer 4b is deformed by a predetermined amount in the belt width direction is used as the back surface side reinforcing layer 4a. It is configured to be larger than the reaction force on the conveying surface side when the predetermined amount is deformed in the width direction.
According to the belt 1 for a pipe conveyor according to the present invention, the back surface side reinforcement layer 4b having a back surface side reaction force larger than the transport surface side reaction force is disposed on the back surface side cover rubber portion 3b. Compared to the case where the force and the back side reaction force are the same, the neutral axis NA of tension-compression is located on the back side B in the belt 1 (in FIG. 1, substantially the same position as the back side reinforcing layer). ) Therefore, since the portion of the belt 1 that receives the compression input closer to the conveying surface A than the neutral axis NA increases, the rigidity when the belt 1 is deformed into a cylindrical shape can be improved, and as a result, An appropriate cylindrical shape can be maintained.

Here, it is preferable that the back surface side reaction force of the back surface side reinforcing layer 4b is twice or more as large as the transport surface side reaction force of the transport surface side reinforcing layer 4a. According to this, the neutral axis NA of tension-compression is located on the back surface B side in the belt 1, and the rigidity when the belt 1 is rounded into a cylindrical shape can be improved more efficiently. The proper cylindrical shape can be held more reliably.
In addition, since the neutral axis NA of tension-compression is located on the back surface B side in the belt 1 as the back surface side reaction force is larger than the transport surface side reaction force, the back surface side reaction force The upper limit for the reaction surface side reaction force is not particularly limited. For example, from the viewpoint of making the rigidity of the pipe conveyor belt 1 appropriate, the back surface reaction force is 2 to 2 with respect to the conveyance surface side reaction force. More preferably, the size is 300 times, and from the same viewpoint, the size is more preferably 20 to 40 times.

  By the way, in order to achieve the relationship between the back surface side reaction force of the back surface side reinforcing layer 4b and the transport surface side reaction force of the transport surface side reinforcing layer 4a as described above, in the embodiment according to the present invention, cord reinforcement is performed. Various ply structures can be employed. For example, weft yarns 6a extending in the belt width direction are juxtaposed in the belt longitudinal direction via warp yarns 6b extending in the belt longitudinal direction. A structure in which the parallel density is greater than the parallel density in the belt width direction of the warp yarn 6b (an interdigital structure illustrated in FIG. 2A), the weft yarn 6a and the warp yarn 6b shown in FIG. Each of which has a plain weave structure woven by alternately raising and lowering at substantially equal intervals, and two staggered two yarns sandwiching the substantially flat warp yarns 6b shown in FIG. 2 (c). Each of the wefts 6a arranged in The weft 6a and warp 6b can be given that such that the straight warp-like structure entangled in a different binder code 6c. Further, from the viewpoint that the reaction force when the reinforcing layers 4a and 4b are deformed by a predetermined amount in the belt width direction can be easily improved, the interdigital structure as described above is preferable. The neutral axis NA of the tension-compression of the conveyor belt 1 can be positioned more effectively on the back surface B side of the belt 1. Therefore, when the belt 1 is rolled up, a proper cylindrical shape can be more sufficiently held.

The cord reinforcing ply structure 6 described above has a structure in which the weft yarns 6a are linearly arranged along the belt width direction, and the warp yarns 6b are meandered with respect to the linear weft yarns 6a. It is preferable. According to this, since the weft yarn 6a is difficult to extend in the belt width direction, the strength in the belt width direction and the reaction force when the reinforcing layer is deformed by a predetermined amount in the belt width direction can be improved.
Furthermore, when the reinforcing layers 4a and 4b are formed of a plurality of layers of cord reinforcing plies, the cord reinforcing plies can have the same or different cord reinforcing ply structure 6 for each cord reinforcing ply.

  Further, the weft 6a and the warp 6b used in the above-described cord reinforcing ply structure 6 are formed by the back surface side reaction force of the back surface side reinforcing layer 4b and the transport surface side reaction force of the transport surface side reinforcing layer 4a as described above. In order to achieve the relationship, the thickness of the cord to be used and the number of driven cords can be changed, and from the viewpoint of improving the strength in the belt width direction, the weft 6a is thicker than the warp 6b. It is preferable to increase the number of driving and / or driving.

Furthermore, examples of the cord used for the reinforcing layer include polyester (PET, PEN, etc.) cord, nylon (aliphatic polyamide) cord, aramid (aromatic polyamide) cord, vinylon cord, rayon cord, or a composite cord thereof. In view of elongation resistance and cost reduction, a polyester cord is preferable. The cords used for the reinforcing layers 4a and 4b are preferably polyester cords, and preferably have the interdigital structure as described above. According to this, the stretch resistance can be further improved.
The cords used for the respective cord reinforcing plies of the reinforcing layers 4a and 4b, and the wefts 6a and warps 6b in one cord reinforcing ply may be the same or different.

  By the way, it is preferable that the conveyance surface side reinforcement layer 4a and the back surface side reinforcement layer 4b are each comprised of one layer of cord reinforcement plies 5a and 5b. According to this, each thickness of the conveyance surface side reinforcement layer 4a and the back surface side reinforcement layer 4b can be made thin. Further, by making the relationship between the back side reaction force of the back side reinforcing layer 4b and the transport side reaction force of the transport side reinforcing layer 4a as described above, the thickness of the belt 1 is efficiently reduced, The rigidity in the state which rolled up the belt 1 for pipe conveyors can be improved. As a result, the amount of cover rubber 3 or the like used for the pipe conveyor belt 1 is reduced, reducing the weight of the belt 1, reducing the manufacturing cost, and reducing the labor when attaching the belt 1 to the belt conveyor device. Furthermore, it can contribute to the energy saving at the time of conveyance of a conveyed product.

When the conveyance surface side reinforcement layer 4a and the back surface side reinforcement layer 4b are each composed of one layer of cord reinforcement ply, the conveyance surface side cord reinforcement ply 5a constituting the conveyance surface side reinforcement layer 4a is arranged in the belt width direction. The measured Young's modulus is 30 to 500 MPa, and the back surface side cord reinforcing ply 5b constituting the back surface side reinforcing layer 4b preferably has a Young's modulus of 800 to 3000 MPa. According to this, the rigidity of the belt 1 can be made more appropriate by setting each Young's modulus within the above range. Specifically, if the rigidity of the belt 1 is too low, the belt 1 may not be retained in a cylindrical shape. If the rigidity of the belt 1 is too high, the belt 1 may be buckled.
The Young's modulus of the transport surface side cord reinforcement ply 5a and the Young's modulus of the back surface side cord reinforcement ply 5b are more preferably 30 to 300 MPa and 900 to 3000 MPa, respectively, and more preferably 30 to 100 MPa and 900-1500 MPa.
The Young's modulus is a strip-shaped test piece with a cord reinforcing ply width of 30 mm, and left in a constant temperature and humidity room at 25 ° C. and 20 to 40% RH for one week. The ss curve (stress-strain curve) is measured by pulling in the direction corresponding to the belt width direction under the condition of a tensile speed of 25 mm / min, and the cord reinforcing ply is stretched by 2 to 5% in the ss curve. It is determined from the slope of the ss curve at the time.

  Here, when the pipe conveyor belt 1 is rolled into a cylindrical shape, both end portions on the outer side in the belt width direction are overlapped with each other, thereby preventing, for example, spilling and scattering of a conveyed product. Yes. Therefore, from the viewpoint of facilitating the overlap of both ends of the belt 1, the widths of the conveying surface side reinforcing layer 4a and the back surface side reinforcing layer 4b arranged at the center in the belt width direction are equal to the width of the belt 1. On the other hand, it is preferably 50 to 95% and 80 to 95%, respectively.

  Here, examples of the reinforcing rubber used for the cover rubber 3 and the cord reinforcing ply include natural rubber, BR (polybutadiene rubber), SBR (styrene butadiene rubber), NBR (acrylonitrile butadiene rubber), or a mixture thereof. A rubber composition in which normally used compounding agents such as a reinforcing agent, a filler, a vulcanizing agent, a vulcanization accelerator, a plasticizer, an antiaging agent, and a processing aid are blended and kneaded. Can be used.

  As mentioned above, although one Embodiment of this invention was described with reference to drawings, the belt for pipe conveyors of this invention is not limited to the said example, The above-mentioned Embodiment of this invention is changed suitably. Can be added.

  EXAMPLES Hereinafter, although an Example demonstrates this invention further in detail, this invention is not limited to the following Example at all.

Example 1
A pipe conveyor belt having a configuration as shown in FIG. Specifically, each of the conveyance surface side reinforcement layer and the back surface side reinforcement layer is composed of one layer of cord reinforcement ply, and each of the back surface side reinforcement layer with respect to the conveyance surface side reinforcement layer is deformed by a predetermined amount in the belt width direction. The reaction force ratio is about 32 times. In addition, the Young's modulus of a conveyance surface side reinforcement layer and a back surface side reinforcement layer is 40 MPa and 1265 MPa, respectively, and each thickness is equivalent.
(Comparative Example 1)
A pipe having the same configuration as in Example 1 except that the ratio of the reaction force when the back surface side reinforcing layer is deformed by a predetermined amount in the belt width direction with respect to the transport surface side reinforcing layer is set to 1 times. A conveyor belt was prototyped and used as Comparative Example 1.

Evaluation was made by the following method.
(Rigidity evaluation)
The obtained belt was rounded into a cylindrical shape and supported by six supporting rollers arranged at equal intervals on the outer periphery thereof. Then, the reaction force (N / mm) of the belt was measured with a load cell attached to the support roller.

From the evaluation of rigidity, the reaction force of the belt of Example 1 was about twice that of the belt of Comparative Example 1, and was larger than that of the belt of Comparative Example 1. Therefore, it has been found that the neutral axis NA of the tension-compression in the belt of Example 1 is located on the back surface side, and therefore, an appropriate cylindrical shape can be maintained when the belt is rolled.
In the belts of Example 1 and Comparative Example 1, both the conveyance surface side reinforcing layer and the back surface side reinforcing layer are each composed of a single cord reinforcing ply, and the thicknesses of the respective belts are the same. It was found that the belt No. 1 can achieve the above-described effects without increasing the thickness.

  ADVANTAGE OF THE INVENTION According to this invention, when a belt is rounded, the belt for pipe conveyors which can hold | maintain an appropriate cylindrical shape can be provided.

DESCRIPTION OF SYMBOLS 1 Belt (belt for pipe conveyors); 2 Core; 3 Cover rubber; 3a Transport surface side cover rubber portion; 3b Back surface cover rubber portion; 4a Transport surface side reinforcing layer; 4b Back surface side reinforcing layer; 5a Transport surface side cord Reinforcement ply; 5b Back side cord reinforcement ply; 6 Cord reinforcement ply structure; 6a Weft; 6b Warp; 6c Binder cord; A Conveying surface; B Back surface; NA Belt tension-compression neutral shaft

Claims (2)

A core body, a cover rubber enclosing the core body, a transport surface side reinforcing layer provided on the belt transport surface side with respect to the core body in the cover rubber, and the core body in the cover rubber A pipe conveyor belt comprising a back side reinforcing layer provided on the back side of the belt,
The back surface side reaction force when the back surface side reinforcing layer is deformed by a predetermined amount in the belt width direction is larger than the transport surface side reaction force when the transport surface side reinforcing layer is deformed by the predetermined amount in the belt width direction. A belt for a pipe conveyor. Each of the transport surface side reinforcing layer and the back surface side reinforcing layer comprises a cord reinforcing ply made of one or more polyester cords,
The back surface side cord reinforcing ply constituting the back surface side reinforcing layer is formed by juxtaposing the weft yarn made of the polyester cord in the belt width direction in parallel with the belt longitudinal direction via the warp yarn extending in the belt longitudinal direction. The conveyor belt according to claim 1, wherein a parallel density in a longitudinal direction of the belt is greater than a parallel density of the warp in the belt width direction.

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