JPH055751B2 - - Google Patents

Description

[Detailed description of the invention]

BACKGROUND AND OBJECTS OF THE INVENTION The present invention relates to a novel handrail used as a handrail for passengers on escalators and autolines. A handrail is a kind of endless belt that is driven continuously and cyclically between drive pulleys by a drive motor. Since escalators and autolines transport an unspecified number of passengers, handrails are subjected to various stresses such as tension, extension, bending, and compression. Generally, the handrail 7 has a C-shaped cross-sectional structure as shown in FIG. In FIG. 1, 1 is a decorative rubber, 2 is a cotton canvas, and 3 is a tension member. The part 4 is the back part of the handrail, and the part 5 is the part called the jaw part of the handrail. A tension member 3 is embedded in the back part 4 to prevent the handrail from elongating in the longitudinal direction. As the tension member 3, steel wire cord, steel tape, glass fiber, synthetic resin, etc. are used. In the handrail 7 in which such a tension member 3 is embedded, the jaw portion 5 should be as flexible as possible in order to have flexibility against bending in the longitudinal direction and maintain the C-shaped shape. is desirable. That is, when the jaw part 5 has poor flexibility, in other words, when it is hard and has little elasticity, when the handrail 7 is bent in the forward direction, the back part 4 will stretch and the jaw part 5 will be compressed. The jaw portion 5 cannot be completely compressed and is wavy like a bellows, and requires a large force for a small bending radius. On the other hand, in the case of reverse bending in which the collar portion 5 is stretched and the back portion 4 is compressed, the tension member 3 will wave, and in extreme cases, the decorative rubber 1 will also be distorted. On the other hand, in recent years, escalators have become simpler in structure and design, and curves have become more acute, so handrails are required to be more flexible than ever before. and again,
In order to save energy in escalator operation, it is required to reduce the running resistance of the handrail and reduce the amount of driving electric power. Conventional handrails that use steel wire as tension members lack flexibility due to the high bending rigidity of the steel wire itself, and require a large amount of force to operate on sharp curves. In addition, with conventional handrails that use synthetic resin as the tension member 3, even if there is no problem with flexibility, the elongation in the longitudinal direction is too large, and the escalator mechanism cannot absorb the elongation during long-term operation. There is. As a method for improving the flexibility of the jaw 5, it is known to embed a bead rubber 6 as shown in FIG. 2 in the tip of the jaw 5. Since the bead rubber 6 is a soft vulcanized rubber linear body, the tip of the handrail flange 5 in which the bead rubber 6 is embedded has flexibility,
In particular, the stretchability of the handrail in the longitudinal direction can be improved to some extent. However, since the flexibility of the bead rubber 6 and the flexibility of the cotton canvas surrounding the bead rubber 6 are different, there is a drawback that the flexibility of the jaw portion 5 of the handrail cannot be completely improved. Furthermore, it is known to use aromatic polyamide fibers called aramid fibers as the tension member 3 in order to prevent the back portion 4 of the handrail from elongating in the length direction. However, when aramid fiber is used as the tension member 3, it is possible to suppress the elongation of the handrail in the length direction;
The forward bending characteristics and reverse bending characteristics of the handrail cannot be improved. The present invention has been made in view of the above, and aims to eliminate the drawbacks of the prior art described above, and to provide a handrail with small elongation in the longitudinal direction and good bending properties. It is about providing rails. [Summary of the Invention] The gist of the present invention is that there is a core body in which cotton canvas is laminated in a strip shape having a substantially C-shaped cross section, a tension member made of aramid fiber is provided on the back of the core body, and In a handrail in which bead rubber is embedded in the tip side of the jaw part of the body, and decorative rubber is vulcanized and adhered to the upper layer of the core body, the thickness of the cotton canvas of the core body in the jaw part is: 20-40% less than the thickness of the core cotton canvas on the back,
The handrail is characterized in that the thickness of the decorative rubber in the jaw part is made relatively thicker by the amount that the thickness of the cotton canvas of the core body in the back part is reduced. The core used in the present invention is made by laminating cotton canvas with a thickness of 0.5 to 2.0 mm, topped with an unvulcanized rubber sheet, into a strip having a substantially C-shaped cross section. The aramid fibers used in the present invention may be of any kind as long as they are obtained from aromatic polyamide fibers obtained by reacting aromatic dibasic acids or their acid chloride salts with aromatic diamines. More commercially available materials such as Kevlar and Nomek can be used. As the decorative rubber, any rubber can be used as long as it has colorability, stain resistance, repeated elongation resistance, and bendability, such as chloroprene rubber, chlorosulfonated polyethylene rubber, styrene-butane diene rubber,
Ethylene propylene rubber, natural rubber, etc. are used. The bead rubber may be any linear vulcanized rubber that reduces the rigidity of the jaw, such as vulcanized styrene-butadiene rubber linear, vulcanized chloroprene linear, vulcanized natural rubber linear, or vulcanized chloro. It may be a sulfonated polyethylene rubber linear body or a composite linear body thereof. In the present invention, the thickness of the cotton canvas core at the chin is set to be 20 mm thicker than the thickness of the cotton canvas core at the back.
By reducing the thickness of the decorative rubber at the chin by ~40% and making the thickness of the decorative rubber at the chin relatively thicker by the reduced thickness of the cotton canvas core at the back, the elongation of the handrail in the longitudinal direction is kept small. This is also to significantly improve the bending characteristics of the handrail. In other words, in order to reduce the elongation of the handrail in the longitudinal direction, all of the cotton canvas should be made of a material with low elongation.
For example, you can replace it with steel wire, etc.
In this case, since the handrail is made of steel wire, its weight increases, and an increase in the electric power cost for driving the handrail is unavoidable. Moreover, handrails made of decorative rubber and steel wire have extremely poor bending properties. On the other hand, in order to improve the bending properties of the handrail, the tension member should not be embedded, the thickness of the cotton canvas should be made extremely thin, and the thickness of the decorative rubber, which has excellent bending properties, should be made relatively thick. However, in such a case, the rigidity of the handrail becomes too large, making it impractical as a handrail. Therefore, the inventors of the present invention conducted intensive studies to reduce the elongation in the length direction of the handrail and improve its bending characteristics. As a result, the bending characteristics of the handrail were determined by the lamination conditions of the decorative rubber and cotton canvas, and the embedding of the bead rubber. The present invention was developed based on the discovery that the presence or absence of tension members, the type of tension member, etc. are intertwined in a complex manner. That is, the present invention reduces the thickness of the cotton canvas core in the chin part by 20 to 40% from the thickness of the cotton canvas core in the back part, and reduces the thickness of the decorative rubber mentioned above to the thickness of the cotton canvas core in the back part. When configured to be relatively thicker by the reduced thickness, the elongation of the handrail in the longitudinal direction is kept small and the bending characteristics of the handrail are significantly improved. If the thickness of the cotton canvas core at the chin decreases by less than 7% than the thickness of the cotton canvas core at the back, the bending properties of the handrail will be inferior; conversely, if the thickness decreases by more than 40%, the This is because the opening force of the escalator becomes too small, causing the handrail to come off the escalator. The effect of the present invention is that by reducing the thickness of the cotton canvas core in the jaw part by a specific range,
It has improved bending properties while maintaining elongation in the length direction. [Example] Next, an example of the handrail of the present invention will be described with reference to the drawings together with a comparative example. Comparative Example 1 As shown in FIG. 3, five sheets of cotton canvas 2 are used, and each of the five sheets wraps around to the tip of jaw 5, and the second and third sheets of cotton canvas 2 are A handrail 7 having a tension member 3 made of aramid fiber inserted therebetween was obtained. Comparative Example 2 As shown in FIG. 4, a handrail 7 having the same configuration as Comparative Example 1 was obtained, except that beat rubber was inserted at the tip of the jaw 5. Example 1 As shown in FIG. 5, five cotton canvases 2 are used, the third canvas from the bottom is fastened at the tip of the back section 4, and the remaining four are attached to the beat rubber 6 at the tip of the jaw section 5.
A handrail 7 which is in contact with is obtained. (Decrease rate 20
%) Example 2 As shown in FIG. 6, a handrail 7 having the same configuration as Comparative Example 1 except that the second and fourth cotton canvases 2 from the bottom of the cotton canvas 2 were stopped at the tip of the back 4. I got it.
(Reduction rate 40%) Comparative Example 3 As shown in Figure 7, from the bottom of cotton canvas 2,
A handrail 7 having the same configuration as Comparative Example 1 was obtained, except that the third and fourth canvases were stopped at the tip of the back portion 4.
(Reduction rate 60%) Comparative Example 4 As shown in Figure 8, a cotton canvas 2 is used, and a tension member 3 made of aramid fiber is embedded between the second and third sheets from the bottom of the cotton canvas 2. A handrail 7 was obtained in which the third cotton canvas 2 from the bottom was fixed at the tip of the back part 4, and the remaining three cotton canvases 2 were in contact with the beat rubber 6 at the tip of the jaw part 5. Comparative Example 5 As shown in FIG. 9, three cotton canvases 2 are used, beet rubber 6 is embedded in the tip of the jaw 5, and a tension member made of aramid fiber is placed between the first and second cotton canvases 2. 3 was embedded, and a handrail 7 was obtained in which the cotton canvas 2 was in contact with the bead rubber 6, respectively. Next, the following tests were conducted on the handrails 7 obtained in the comparative examples and examples thus obtained.
The following table shows the test results.

[Table] The test method is as follows. Forward bending test, reverse bending test A forward bending test refers to a test in which the handrail 7 in Figure 1 is bent downwards using two points in the length direction as fulcrums, and a reverse bending test is a test in which the handrail is bent upwards. It refers to an exam. Bending Stiffness Test The bending stiffness test is to determine the amount of deflection of the handrail 7 when the handrail is supported at two points and a load of 5 kgf is applied from the top of the center as shown in Figure 10. . Jaw opening force measurement test The jaw opening force measurement test is as shown in Figure 11.
The handrail 7 was held in the opposite direction, and the force was measured when the jaw part was fully opened outward.
Note that if the opening force of the handrail 7 is small, it means that the handrail 7 is likely to come off when it is attached to an escalator or an auto line and operated. In practical terms, it is known that if the opening force is not 25 kg or more, it will easily come off. As can be seen from the table, the handrail 7 of Comparative Example 1 has the characteristics of a large opening force of the jaw portion 5 and low elongation, but has poor forward bendability and reverse bendability. It has the lowest directional bending rigidity. Although the handrail 7 of Comparative Example 2 has good forward bendability, it has poor reverse bendability. On the other hand, the handrails 7 of Comparative Examples 3 to 5, in which the thickness of the cotton canvas 2 of the core body in the jaw part 5 is made thinner overall, and the thickness of the decorative rubber 1 is made relatively thicker, have good forward bendability and reverse bendability. Although the bendability in the direction is improved, the bending stiffness in the reverse direction becomes extremely large, and as a result, there is a drawback that the opening of the jaw portion 5 is reduced to 25 kg or less. For these, Example 1 and Example 2 of the present invention
The handrail 7 has good bendability, rigidity, opening force of the jaw portion 5, and elongation characteristics. [Effects of the Invention] The handrail of the present invention has good bending properties, moderate rigidity, and low elongation, and is industrially useful.

[Brief explanation of the drawing]

Figure 1 is a cross-sectional view of a conventional handrail 7 , Figure 2 is a cross-sectional view of a conventional handrail 7 with embedded bead rubber 6, and Figures 3, 4, 8, and 9 are comparisons. An explanatory diagram showing the core structure of the handrail 1 used in the example, and FIGS. 5 to 7 are explanatory diagrams showing the core structure of the handrail used in the example of the handrail 7 of the present invention. . FIG. 10 is an explanatory diagram of a reverse bending rigidity test of the handrail 7 , and FIG. 11 is an explanatory diagram of an opening test of the jaw portion 5. 1: Decorative rubber, 2: Cotton canvas, 3: Tension member, 4: Back, 5: Jaw, 6: Bead rubber,
7: Handrail.

Claims (1)

[Claims] 1. There is a core body in which cotton canvas 2 is laminated in a strip shape having a substantially C-shaped cross section, a tension member 3 made of aramid fiber is embedded in the back part 4 of the core body, and a jaw part of the core body Bead rubber 6 on the tip side of 5
In the handrail formed by vulcanizing and adhering decorative rubber 1 to the upper layer of the core, the thickness of the cotton canvas 2 of the core in the jaw part 5 is equal to the thickness of the core of the cotton canvas 2 in the back part 4. 20 from the thickness of cotton canvas 2
- 40%, and the thickness of the decorative rubber 1 in the jaw part 5 is made relatively thicker by the amount that the thickness of the cotton canvas 2 of the core body in the back part 4 is reduced. .