JP3984140B2 - Guide roller manufacturing method - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to a guide roller manufacturing method in which a rope is guided by an outer peripheral surface, and an inner peripheral surface is supported by a support portion.
[0002]
[Prior art]
Guide rollers for guiding ropes are used in gondolas, ski lifts, ropeways, and the like. Such guide rollers are disclosed in, for example, Japanese Patent Laid-Open Nos. 7-315214 and 5-162637. A general structure of the guide roller will be described with reference to FIG.
[0003]
FIG. 5 is a cross-sectional view of the guide roller cut along a plane passing through the rotation center CE. The guide roller 100 includes a rubber layer 101 that does not include a reinforcing cord made of fiber, and a reinforcing layer 102 made of a reinforcing cord. A shallow V-shaped guide groove 101a is formed on the outer peripheral surface of the rubber layer 101, and the rope R is guided. Further, the inner peripheral surface of the rubber layer 101 is supported by a pipe 103 (support portion). The reason why the reinforcing layer 102 is provided is that a large stress acts between the support portion and the strength while the rotational force from the rope R is acting to ensure the strength. On the other hand, the outer peripheral surface is not reinforced with a reinforcing cord in order to absorb vibration and impact from the rope.
[0004]
[Patent Document 1]
Japanese Patent Laid-Open No. 7-315214, FIGS. 1-4, etc. [Patent Document 2]
Japanese Patent Laid-Open No. 5-162637, FIG. 1, FIG. 2, etc.
Conventionally, the manufacture of the guide roller has a process of winding a fiber as a reinforcing cord and a process of winding a rubber. Since these are performed in separate processes, there is a problem that the manufacturing time becomes long. In addition, since the interlayer rigidity between different materials (fiber and rubber) changes abruptly, shearing force is generated when a high load is applied, causing delamination.
[0005]
This invention is made | formed in view of the said situation, The subject is providing the manufacturing method of the guide roller which can improve the problem of the delamination between dissimilar materials, and the fracture | rupture of a rubber layer.
[Means for Solving the Problems]
In order to solve the above problems, a method for manufacturing a guide roller according to the present invention includes:
A method of manufacturing a guide roller in which a rope is guided by an outer peripheral surface, and an inner peripheral surface is supported by a support part,
A step of extruding a strip-shaped reinforcing rubber in which short fibers are mixed with rubber; and
Winding the extruded reinforcing rubber around a molding drum, and sequentially forming a rubber layer from the inner peripheral surface side toward the outer peripheral surface side,
It is characterized in that the amount of short fibers mixed is reduced in the direction from the inner peripheral surface to the outer peripheral surface.
[0006]
The actions and effects of this manufacturing method are as follows. First, a rubber layer is sequentially formed by using a strip-like reinforcing rubber obtained by extruding, in which short fibers are mixed in a rubber, and winding this around a molding drum. In this way, the reinforcing cord and the rubber are not wound separately, but the reinforcing rubber mixed with the short fibers is used, so that the problem of delamination can be reduced or eliminated. Moreover, when winding around a forming drum, the amount of short fibers mixed is increased on the inner peripheral surface side, and the amount of short fibers mixed is gradually decreased toward the outer peripheral surface side. Thereby, a sudden change in rigidity can be suppressed. As a result, it is possible to provide a guide roller manufacturing method capable of improving the problem of delamination between different materials and the breaking of the rubber layer.
As a preferred embodiment of the present invention, an extrusion apparatus used for extruding reinforcing rubber is provided with a hopper for feeding a rubber ribbon, and the rubber ribbons fed into this hopper have different mixing amounts of short fibers. A plurality of rubber ribbons are prepared, and rubber ribbons with a large amount of mixing are used on the inner peripheral surface, and rubber ribbons with a small amount of mixing are used toward the outer peripheral surface.
[0007]
When extruding a strip rubber using an extrusion device, a rubber ribbon is put into the hopper. A plurality of ribbons having different amounts of short fibers are prepared in the rubber ribbon. On the inner peripheral surface, the one having a large amount of short fibers mixed is used, and the rubber ribbon is switched to a smaller amount as the outer peripheral surface is reached. Thereby, a rubber layer in which the amount of short fibers is gradually reduced can be formed.
[0008]
As another preferred embodiment of the present invention, a first hopper for injecting a rubber ribbon into an extrusion apparatus used for extruding reinforcing rubber, and a second for injecting short fibers downstream of the first hopper in extrusion. A hopper is provided, and the amount of short fibers mixed in can be controlled by changing the amount of short fibers fed from the second hopper.
[0009]
As another method for controlling the amount of short fibers mixed, an extrusion apparatus provided with a first hopper and a second hopper is used. From the first hopper, a rubber ribbon in which short fibers are not mixed is introduced. Short fibers are fed from a second hopper located downstream of the first hopper by extrusion. The amount of short fibers contained in the rubber layer can be controlled by the amount of short fibers mixed.
[0010]
DETAILED DESCRIPTION OF THE INVENTION
A preferred embodiment of a guide roller manufacturing method according to the present invention will be described with reference to the drawings. FIG. 1 is a conceptual diagram showing a configuration of an extrusion device used in a method for manufacturing a guide roller.
[0011]
<Configuration of extrusion device>
The extrusion apparatus 1 includes an extruder 10 and a gear pump 11. The extruder 10 includes a cylindrical cylinder 10a and a screw 10b provided inside the cylinder 10a. The screw 10b is rotationally driven by a driving device (not shown). Moreover, the screw 10b can reciprocate also in the front-back direction. A hopper 10c is provided above the cylinder 10a, from which the rubber ribbon 30 is introduced. The introduced rubber ribbon 30 is kneaded and plasticized by friction between the screw 10b and the inner surface of the cylinder 10a.
[0012]
The gear pump 11 has a function of extruding a predetermined amount of rubber, and includes a pair of gears 11a. A die 12 is provided at the tip of the gear pump 11, from which a strip-like rubber having a predetermined cross-sectional shape is extruded. A molding drum 20 is provided at a position facing the extrusion device 1, and the rubber extruded from the die 12 is wound around the outer peripheral surface of the molding drum 20 while being guided by the guide roller 13. The forming drum 20 is rotationally driven by a driving device (not shown).
[0013]
The rubber ribbon 30 introduced from the hopper 10c is prepared with a short fiber mixed beforehand and a rubber ribbon 30 not mixed at all. Moreover, about what mixes a short fiber, the thing with which mixing amount differs is prepared in multiple numbers. FIG. 1 illustrates four rubber ribbons. These differ in the amount of short fibers mixed in.
[0014]
<Guide roller structure>
FIG. 2 is a sectional view in which a guide roller manufactured according to the present invention is partially broken. The rubber layer has a five-layer structure of first rubber layer S1... Fifth rubber layer S5 in order from the inner peripheral surface side. Short fibers are mixed in the first rubber layer S1 to the fourth rubber layer S4, and the amount of mixed short fibers increases as the rubber layer is closer to the inner peripheral surface. Short fibers are not mixed in the outermost fifth rubber layer S5. The layer structure is not limited to this. For example, the number of layers may be increased or decreased.
[0015]
In order to form such a rubber layer using the extrusion device of FIG. 1, first, the first rubber layer S1 is wound around the molding drum 12 by the rubber ribbons 30A and 30D. Next, the second rubber layer S2 is formed using the rubber ribbons 30B and 30D. Next, the third rubber layer S3 is formed using the rubber ribbons 30A, 30B, and 30D. Next, the fourth rubber layer S4 is formed using the rubber ribbons 30C and 30D. The last fifth rubber layer S5 uses a rubber ribbon in which short fibers are not mixed.
[0016]
In the above example, a plurality of types of rubber ribbons are combined and loaded from the hopper 10c, but a single rubber ribbon may be loaded. Alternatively, one or a plurality of types of rubber ribbons may be introduced. That is, the rubber ribbon charging mode is not limited to a specific one.
[0017]
The width of the strip rubber extruded from the die 12 may be the same as the width of the guide roller as a product, or may be smaller than the width of the guide roller. When the width of the strip rubber is small, the rubber layer shown in FIG. 2 can be formed if the extrusion device 1 is configured to reciprocate in the width direction of the forming drum 20 (direction perpendicular to the paper surface of FIG. 1). it can.
[0018]
Examples of the short fiber include nylon, aramid, polyester, carbon, steel and the like, but are not limited to a specific material. The length of the short fiber is preferably 100 μm to 20 mm. If the fiber diameter is 1/50 or less of the length, the balance between elongation and load is improved as a composite material of short fibers and rubber. Although the short fibers and the rubber are effective even if they are not bonded, they are preferably bonded from the viewpoint of fatigue when subjected to repeated loads.
[0019]
<Another embodiment of the extrusion apparatus>
Next, an extrusion apparatus according to another embodiment will be described with reference to FIG. 3 is different from FIG. 1 in that there are provided a first hopper 10c and a second hopper 10d. The 1st hopper 10c is provided in the base side of the screw 10b, and the rubber ribbon 31 is thrown in. Short fibers are not mixed in the rubber ribbon 31. A second hopper 10d is provided on the downstream side of the first hopper 10c, and short fibers are input. The amount of short fibers mixed in each rubber layer can be controlled by changing the amount of short fibers input from here.
[0020]
<Effect>
The guide roller manufactured according to the present invention has the following operations and effects. As the rubber material, soft rubber having sufficient vibration absorption is used. Even if an impact load is applied, the load can be dispersed over a wide range to prevent the rubber from breaking. On the inner peripheral surface side, sufficient rigidity is secured by the short fibers, and the outer peripheral surface in contact with the rope is softened. Further, the distribution of the amount of short fibers is preferably increased toward the center of the guide roller, and is increased toward the inner peripheral surface. In this case, the strength of the guide roller becomes stronger toward the center in the width direction. On the other hand, the rotational force received from the rope is greater at the center. In the guide roller having such a configuration, the stress is uniform over the width direction. Due to the contact with the rope, the strain on the outer surface is 10 to 20%, but the amount of strain decreases as the inner layer is reached. Thereby, the gap between the innermost first rubber layer S1 and the support portion is eliminated. Moreover, in this invention, the rubber layer from which the mixing amount of a short fiber differs can be shape | molded continuously. This eliminates a decrease in the bonding strength between the layers. In addition, since the amount of mixing is gradually reduced from the inner peripheral surface toward the outer peripheral surface, a sudden decrease in rigidity is prevented.
[0021]
Furthermore, in the manufacturing method according to the present invention, a rubber layer reinforced with short fibers is formed. Conventionally, the winding of the reinforcing cord and the winding of the rubber layer are separate processes, so that the manufacturing time is increased and there is a problem of delamination between different materials. However, in the case of the present invention, such a problem hardly occurs. No (or nothing at all). Moreover, in the state exposed to rainwater, rainwater permeates from the end of the fiber, and there is no possibility of causing deterioration and peeling.
[0022]
<Experimental result>
Specific dimensions of the guide roll are an inner diameter of 300 mm, an outer diameter of 420 mm (thickness of 60 mm), and a width of 80 mm. The amount and thickness of the short fibers mixed in each rubber layer are as follows: the first rubber layer S1 is 3 mm for the short fibers 10PHR, the second rubber layer S2 is 3mm for 7PHR, the third rubber layer S3 is 6mm for 5PHR, and the fourth rubber layer. S4 is 6 mm at 3 PHR, and the fifth rubber layer S5 is a natural rubber not containing short fibers and has a hardness of 70 °. The same rubber is used in the other rubber layers S1 to S4.
[0023]
The strain of the rubber on the outer surface due to contact with the rope is 10 to 20%, and this gradually decreases as it goes to the inner peripheral surface, and the deviation between the first rubber layer S1 and the rim (support portion) is eliminated. Like that. In the present invention, even if 20% strain is generated in the fifth rubber layer S5, 14% in the fourth rubber layer S4, 10% in the third rubber layer S3, 6% in the second rubber layer S2, Since 1 rubber layer S1 is 5% and gradually decreases, it can be fixed to the rim without causing separation between the layers. In the manufacturing method according to the prior art, since the strain does not change from the outer peripheral surface to the inner peripheral surface, slip occurs between the first rubber layer S1 and the rim.
[0024]
Comparison was made between the invention product and the conventional product. In the conventional product, the outer dimensions of the above-mentioned numerical values were adopted, and three layers of 1260 d / 2 (1260 denier / 2 twisted) polyester sudda records were wound on the inner peripheral surface side. This was subjected to a rotation test with a 180-degree endless rope, and the comparison was made by attaching a conventional product on one side and an inventive product on the other side with a rope load of 500 kg and a rope speed of 5 m / sec. The conventional product slipped with the rim in 150 hours. On the other hand, the abnormality did not occur in the inventive product even after the 300-hour test. In the conventional product, peeling occurred between the reinforcing cord and the rubber after the 260-hour test.
[0025]
FIG. 4 is a graph showing the relationship between the load and the amount of rubber elongation. The graph shows the case where the amount of short fibers is 0PHR, 3PHR, 5PHR, 7PHR, and 10PHR. A straight line L indicates the elongation percentage of rubber when the first rubber layer S1 is used as a reference. The amount of short fibers mixed in the present invention is preferably such that the relationship between the load and elongation as rubber is changed twice. That is, 1 PHR or more is preferable. Moreover, the upper limit of the amount of short fibers mixed is determined by whether or not 5% of repeated elongation as rubber can be tolerated.
[0026]
<Another embodiment>
In FIG. 2 of the present embodiment, the width of each rubber layer matches the width of the guide roller, but is not limited to this. The width of each rubber layer can also be determined so that the rigidity becomes higher toward the center side in the width direction.
[0027]
The extrusion apparatus used in the present invention preferably has the ability to increase the screw rotation speed when the rubber supply amount is small and to automatically decrease the screw rotation speed when the rubber supply amount is large. Moreover, the structure which mixes the rubber | gum from several extruders by making a plurality of extruder parts into the extrusion front end side (die side) is also employable.
[Brief description of the drawings]
FIG. 1 is a conceptual diagram showing a configuration of an extrusion device used in a guide roller manufacturing method. FIG. 2 is a cross-sectional view in which a guide roller is partially broken. FIG. 3 is a conceptual diagram showing a configuration of an extrusion device according to another embodiment. FIG. 4 is a graph showing the relationship between the load and the amount of rubber elongation. FIG. 5 is a diagram showing the structure of a guide roller according to the prior art.
DESCRIPTION OF SYMBOLS 1 Extruder 10 Extruder 10c 1st hopper 10d 2nd hopper 20 Molding drum 30, 31 Rubber ribbon S1-S5 Rubber layer 32 Short fiber

Claims (3)

A method of manufacturing a guide roller in which a rope is guided by an outer peripheral surface, and an inner peripheral surface is supported by a support part,
A step of extruding a strip-shaped reinforcing rubber in which short fibers are mixed with rubber; and
Winding the extruded reinforcing rubber around a molding drum, and sequentially forming a rubber layer from the inner peripheral surface side toward the outer peripheral surface side,
A method of manufacturing a guide roller, characterized in that the amount of short fibers mixed in decreases from the inner peripheral surface toward the outer peripheral surface. The extrusion equipment used to extrude the reinforced rubber is provided with a hopper that throws in the rubber ribbon. Prepare a plurality of rubber ribbons with different amounts of short fibers to be fed into the hopper. 2. The method for manufacturing a guide roller according to claim 1, wherein a rubber ribbon with a large amount of mixing is used, and a rubber ribbon with a small amount of mixing is used toward the outer peripheral surface. The extrusion apparatus used for extruding the reinforcing rubber is provided with a first hopper for injecting a rubber ribbon and a second hopper for injecting short fibers on the downstream side of the extrusion of the first hopper. The method for manufacturing a guide roller according to claim 1, wherein the amount of short fibers mixed is controlled by changing the amount of short fibers fed from the base.

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