JP2005336988A - Vibration control sleeper - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To increase coefficient of loss and provide satisfactory vibration control property by constituting a restraining layer with a metal having large Young's modulus, to hold electric insulation property of two rails even when a laminated body composed of a vibration control sheet layer and a metallic restraining layer comes into contact with the rails by covering an upper face and both side faces of the metallic restraining layer with an insulation material, to prevent possibility of transmission of an erroneous signal due to conductivity between the rails, and also to prevent a vibration control member from being peeled off when load is applied and a sleeper is bent. <P>SOLUTION: This vibration control sleeper 14 is constituted in such a way that the laminated body 3 composed of the vibration control sheet layer 1 made of an organic high polymer material and the metallic restraining layer 2 bonded on one face of the vibration control sheet layer 1 is bonded to a part between the rails 13 on an upper face of the sleeper 5 on a vibration control sheet layer 1 side and a side face and/or a bottom face (preferably, the laminated body 3 is divided and bonded) to cover the upper face and both side faces of the metallic restraining layer 2 with the insulation material 4. <P>COPYRIGHT: (C)2006,JPO&NCIPI

Description

  The present invention relates to railroad sleepers that have vibration damping performance and can suppress the generation of noise.

Conventionally, noise generated from sleepers as a train travels has become a problem. As a solution, Patent Document 1 discloses a damping material made of a resin composition having damping properties on the surface of a metal sleeper. A method has been proposed in which a hard resin layer is provided on a layer and the damping material layer to act as a constraining layer, and noise generation from sleepers is suppressed by the damping effect of these layers.
Japanese Patent Laid-Open No. 7-216801

  In general, the restraint type damping material exhibits better damping properties as the Young's modulus of the restraining material increases. In the method of Patent Document 1, since the layer acting as the constraining layer is made of a hard resin, the Young's modulus is relatively small, and therefore the vibration damping effect is low. If the layer acting as the constraining layer is a metal layer having a large Young's modulus, the metal layer is exposed on the surface of the obtained vibration damping sleeper. As a result, the electrical insulation of the two rails is not maintained due to the metal layer, and an erroneous signal is generated due to the conduction between the rails, which may cause an accident.

  In addition, when a load is applied to the vibration damping sleeper such as when passing through a train, the vibration damping material may easily peel off due to the sleeper bending.

  It is an object of the present invention to provide a vibration damping sleeper that can solve the above-described problems of the prior art, and to make it difficult for the vibration damping material to peel off when a load is applied and the sleeper is bent. To do.

  The vibration damping sleeper according to the present invention includes a vibration damping sheet in which a laminate composed of a vibration damping sheet layer made of an organic polymer material and a metal constraining layer is formed on a portion between rails on the upper surface of the sleeper, a side surface, and / or a bottom surface. The layers are bonded together, and the upper surface and both side surfaces of the constraining layer are covered with an insulating material.

  Preferably, in the vibration damping sleeper of the present invention, the laminated body is divided into a plurality of pieces and bonded to follow the bending of the vibration damping sleeper.

  In this case, for example, as shown in FIG. 4B, even when the damping sleeper is bent due to a load at the time of passing through the train, it is preferable in that the laminated body and the sleeper are securely bonded and are not easily peeled off. .

  The organic polymer material used in the present invention is preferably composed of a chlorine-containing thermoplastic resin and chlorinated paraffin.

  A preferable example of the organic polymer material is a chlorine-containing thermoplastic resin having a chlorine content of 20 to 70% by weight, a crystallinity measured by DSC method of 5 J / g or more, and a weight average molecular weight of 400,000 or more. 200 to 1000 parts by weight of chlorinated paraffin having a chlorine content of 30 to 75% by weight and a number average carbon number of 12 to 50 and 400 to 1000 parts by weight of an inorganic filler are blended with 100 parts by weight. It will be.

  As the chlorine-containing thermoplastic resin which is one constituent component of the organic polymer material, a thermoplastic resin containing 20 to 70% by weight of chlorine is preferable. If the chlorine content of the chlorine-containing thermoplastic resin is less than 20% by weight, crystals of the resin are likely to grow, so the storage elastic modulus is increased, the loss tangent (tan δ) value is reduced, and the damping performance is reduced. descend. If the chlorine content exceeds 70% by weight, the intermolecular force becomes too strong, so that the storage elastic modulus becomes high, the loss tangent value becomes small, and the damping performance decreases.

  The chlorine-containing thermoplastic resin may contain a substituent other than chlorine, for example, a cyano group, a hydroxyl group, an acetyl group, a methyl group, an ethyl group, bromine, fluorine and the like in a range of 5% by weight or less. If the ratio of such substituents other than chlorine exceeds 5% by weight, vibration damping performance may be reduced.

  Specific examples of the chlorine-containing thermoplastic resin include chlorinated polyethylene, polyvinyl chloride, chlorinated polyvinyl chloride, and vinyl chloride-vinyl acetate copolymer.

  The weight average molecular weight of the chlorine-containing thermoplastic resin is preferably 400,000 or more. This is because when the weight average molecular weight is less than 400,000, it becomes difficult for the vibration damping sheet to retain its shape and strength when 200 parts by weight or more of chlorinated paraffin is blended.

  The crystallinity measured by the DSC method of the chlorine-containing thermoplastic resin is preferably 5 J / g or more. This is because if the crystallinity is less than 5 J / g, the resin composition tends to flow at a high use temperature. The upper limit of the crystallinity is not particularly limited, but if the crystallinity becomes too high, the storage elastic modulus becomes high and the loss tangent value may be reduced, so that the vibration damping performance may be lowered. / G or less is preferable.

  As a chlorinated paraffin which is another component of the organic polymer material, those having a chlorine content of 30 to 75% by weight are preferable. This is because if the chlorine content is outside the above range, the compatibility with the chlorine-containing thermoplastic resin is deteriorated, and the vibration damping sheet layer hardly exhibits the vibration damping performance.

  The number average carbon number of the chlorinated paraffin is preferably 12-50. If the number average carbon number is less than 12, the chlorinated paraffin tends to bleed out, and the vibration damping performance may deteriorate over time. If the number average carbon number exceeds 50, the viscosity will be too high and handle. This is because it is difficult.

  The chlorinated paraffin can be used in combination of a plurality of types having a chlorine content of 30 to 75% by weight and a number average carbon number of 12 to 50.

  The organic polymer material preferably contains an inorganic filler. The inorganic filler is not particularly limited, but calcium carbonate, mica, and the like are preferable from the viewpoint of easy availability and easy development of vibration damping properties. The particle size of the inorganic filler is not particularly limited, but the average particle size is preferably in the range of 100 to 100,000 nm from the viewpoint of dispersibility in the resin composition and ease of exhibiting vibration damping properties. .

  The metal constrained layer only needs to have a high Young's modulus. For example, a constrained layer made of a metal material such as lead, iron, steel (including stainless steel), aluminum (including aluminum alloy), or the like is used. The size of the metal constraining layer is preferably the same as that of the vibration damping sheet layer.

  The insulating material is coated on the upper surface and both side surfaces of the metal constraining layer. In order to prevent the metal constraining layer from coming into contact with the rail, the insulating material must be coated on both sides of the metal constraining layer. The thickness of the insulating material is not particularly limited, but is preferably in a range that has insulating performance and does not deteriorate workability, for example, 1 to 1000 μm. Examples of the insulating material include commercially available insulating varnish, insulating paint, resin film, and the like.

  In the vibration damping sleeper according to the present invention, since the constraining layer is made of a metal having a large Young's modulus, the loss factor becomes high and good vibration damping properties can be exhibited.

  In addition, since the upper surface and both side surfaces of the metal constraining layer are covered with an insulating material, even if a laminate comprising the vibration damping sheet layer and the metal constraining layer contacts the rail, the electric insulation of the two rails Is maintained and there is no risk of false signal transmission due to continuity between rails.

  Furthermore, when a laminated body is divided | segmented into several and bonded together, when a load is applied and a sleeper bends, a damping material is hard to peel off.

  Embodiments of the present invention will be described below with reference to the drawings.

Example 1
In FIG. 1, a vibration damping sleeper (14) includes a vibration damping sheet layer (1) made of an organic polymer material and a metal constraining layer (2) bonded to one side of the vibration damping sheet layer (1). The laminate (3) is bonded to the portion between the rails (13) on the upper surface of the sleeper (5) on the vibration damping sheet layer (1) side, and an insulating material is formed on the upper surface and both side surfaces of the metal constraining layer (2). (4) is coated.

  The damping sheet layer (1) is a chlorinated polyethylene obtained by post-chlorination of high-density polyethylene by a water suspension method (weight average molecular weight 500,000, chlorine content 40% by weight, crystallinity 10J / measured by DSC method). g) 100 parts by weight, chlorinated paraffin (manufactured by Ajinomoto Fine Chemical Co., Ltd., trade name “Empara K50”, chlorine content 50% by weight, number average carbon number 14), 400 parts by weight, calcium carbonate (manufactured by Maruo Calcium Co., Ltd., trade name) 400 parts by weight of “R heavy coal”) were kneaded at 120 ° C. using a roll kneader, and the obtained resin kneaded product was pressed at 140 ° C. to form a sheet having a thickness of 1.0 mm.

  The laminated body (3) has a 0.3 mm thick steel plate (manufactured by Nakamura Shoji Co., Ltd., longitudinal elastic modulus 250 GPa) as the metal constraining layer (2), and the vibration damping sheet layer (1). ) And using the adhesive property.

  This laminate (3) is controlled with the damping sheet layer (1) on the entire outer surface of the sleeper (5) (trade name “FFU sleeper” manufactured by Sekisui Chemical Co., Ltd., size: 20 cm × 14 cm × 240 cm). It bonded together using the adhesiveness of a vibration sheet layer (1).

  The insulating material (4) is formed by applying an insulating paint (trade name “FD coat” manufactured by Takashi Kubo Paint Co., Ltd.) with a thickness of 20 μm on the upper surface and both side surfaces of the constraining layer (2).

Damping evaluation test The laminate (3) composed of the damping sheet layer (1) and the metal constraining layer (2) used in Example 1 was placed on the entire surface of the sleeper (5) on the damping sheet layer (1) side. And an insulating paint was applied to the entire surface of the metal constraining layer (2) to cover the insulating material (4). The vibration damping sleepers (6) thus obtained were hung on a pair of iron girders (7) of the vibration damping evaluation device and fixed with hook bolts (8). The simulated rail (9) was placed on the top surface of the vibration damping sleeper (6), and this was struck by an impulse hammer (11) of the vibration exciter (10). On the impulse hammer (11) and the protrusion (12) provided on the lower surface of the sleeper, the vibration acceleration level was measured at the addition average level of the vibration acceleration level of 1/3 octave band frequency and 200 to 2500 Hz. Moreover, the vibration acceleration level was measured by the same method as described above for the sleepers (blank sleepers) not having the laminate (3) and the insulating material (4). The measurement result was 110 dB for the damping sleeper and 112 dB for the blank sleeper.

Example 2
As shown in FIG. 5, it was carried out similarly to Example 1 except having laminated the laminated body (3) into 4 parts, and bonding together on the both sides | surfaces and bottom face of the sleeper (5).

  The insulating material (4) is formed by applying an insulating paint (trade name “FD Coat” manufactured by Takashi Kubo Paint Co., Ltd.) with a thickness of 20 μm on the upper surface and both side surfaces of the laminate (3). It was created.

Damping evaluation test The damping sleeper (6) obtained as described above was passed over a pair of iron girders (7) of the damping evaluation device and fixed with hook bolts (8) as shown in FIG. The simulated rail (9) was placed on the top surface of the vibration damping sleeper (6), and this was struck by an impulse hammer (11) of the vibration exciter (10). On the impulse hammer (11) and the protrusion (12) provided on the lower surface of the sleeper, the vibration acceleration level was measured at the addition average level of the vibration acceleration level of 1/3 octave band frequency and 200 to 2500 Hz. Moreover, the vibration acceleration level was measured by the same method as described above for the sleepers (blank sleepers) not having the laminate (3) and the insulating material (4). The measurement result was 110 dB for the damping sleeper and 112 dB for the blank sleeper.

Three-point bending fatigue test Further, the vibration-damping sleeper (6) was obtained in the same manner as above except that the four-layered laminate was bonded only to both sides of the sleeper (the length of each laminate was 595 mm, the interval was 5 mm). The fatigue test was conducted by repeating the three-point bending test (length of vibration damping sleeper 2400 mm, support span interval 1600 mm, loading load 8000 kgf, loading center deflection 10 mm) as shown in FIG. Moreover, also about the sleeper which has not divided | segmented the laminated body (3), the 3 point | piece bending fatigue test was done by the same method as the above. The test results showed that the laminated sleeper was not separated at all even after 10 ⁶ cycles, whereas the laminate was not separated at 1 cycle when the laminate was not divided. Peeling was observed.

It is a front view which shows the vibration damping sleeper by Example 1. FIG. It is an expanded sectional view which shows the principal part of FIG. It is a front view which shows a vibration suppression evaluation test. It is explanatory drawing which illustrates a damping sleeper at the time of dividing | segmenting a laminated body, (a) is a schematic diagram of the normal time without a load on a rail, (b) shows the state by which the load was loaded at the time of train passing It is a schematic diagram. 6 is a schematic diagram illustrating a vibration damping sleeper used in a vibration damping evaluation test of Example 2. FIG. 6 is a schematic diagram for explaining a three-point bending display test of Example 2. FIG.

Explanation of symbols

(1): Damping sheet layer (2): Constraining layer (3): Laminate (4): Insulating material (5): Sleeper (13): Rail (14): Damping sleeper

Claims (3)

  A laminated body composed of a vibration damping sheet layer made of an organic polymer material and a metal constraining layer is bonded to the portion between the rails on the upper surface of the sleeper, the side surface, and / or the bottom surface. Damping sleepers, with an insulating material coated on the top and sides.   The vibration damping sleeper according to claim 1, wherein the laminated body is divided into a plurality of pieces and bonded to be able to follow the bending of the vibration damping sleeper. The damping sleeper according to claim 1 or 2, wherein the organic polymer material is a resin composition comprising a chlorine-containing thermoplastic resin and a chlorinated paraffin.

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