JP2010223372A - Air spring for railway vehicle - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide an air spring for railway vehicles which improves the ease of sliding of a sliding part between a diaphragm and a lower support part thereof without deteriorating strength and whose durability can further be improved by avoiding the premature wear of the lower part of the diaphragm and by surely and stably exhibiting expected performance over a long period of time. <P>SOLUTION: The air spring for railway vehicles includes the diaphragm 3 made of an elastic material provided over an vehicle-side upper support part 1 and the carriage-side lower support part 2 arranged below the upper support part. In this air spring, a support plate 24 made of rubber is disposed on a part 2b of the lower support part 2, on which a lower bead part 3d of the diaphragm 3 is mounted and received. The upper surface part 24A that receives the lower bead part 3d on the support plate 24 is reinforced and formed with rubber containing short aramid fibers 6 mm long. <P>COPYRIGHT: (C)2011,JPO&INPIT

Description

  The present invention relates to an air spring for a railway vehicle in which a diaphragm made of an elastic material is provided over an upper support portion on a vehicle body side and a lower support portion on a cart side disposed above the vehicle body side upper support portion.

  In this type of railcar air spring, horizontal displacement in the left-right and front-rear directions acts on the diaphragm, which is the main part, with meandering and turning during vehicle travel. In particular, in the case of a railway vehicle in which a bolsterless bogie is adopted as the bogie, the horizontal displacement becomes very large. In such a horizontal displacement, the diaphragm and the upper support portion and the lower support portion are in contact with each other, so that the sliding friction resistance between them is large, the spring constant is large, and the horizontal displacement behavior is poor. It is difficult to obtain the original buffer performance. In addition, since the sliding frictional resistance is large, the diaphragm is easily worn, and may be damaged or punctured and become unusable at an early stage.

  Since the lower support portion has a smaller pressure receiving area than the upper support portion and has a higher pressure per unit area, that is, a sliding pressure, the contact condition with the diaphragm is more severe. Therefore, the lower support part is devised to reduce the deformation due to the vertical load and to set the height high and to make the rubber of the diaphragm receiving part a high hardness rubber so that the horizontal displacement can be taken. The composition is taken. For this reason, the rubber diaphragm is more distorted than the lower support portion, and damage due to relative sliding tends to be biased toward the diaphragm. As such a prior art, what is disclosed in Patent Document 1 is known.

  The one disclosed in Patent Document 1 has a structure in which an NR high hardness rubber is bonded to a diaphragm made of NR (natural rubber). However, since recent diaphragms are often made of CR (chloroprene rubber) which is excellent in wear resistance and elasticity, it is unsuitable to adopt a structure having a partially hard rubber as described above.

Therefore, in order to avoid early damage of the diaphragm at the joint portion between the diaphragm and the lower support portion, there is room for further improvement, such as a new device being required.
JP 2003-172391 A

  In view of the above circumstances, the object of the present invention is to improve the slipperiness of the sliding portion between the diaphragm and the lower support portion without causing a decrease in strength, and to suppress or avoid early wear and wear of the lower portion of the diaphragm. Thus, it is an object to provide an air spring for a railway vehicle that can reliably and stably exhibit desired performance for a long period of time and can further improve durability.

The invention according to claim 1 is an air spring for a railway vehicle in which an elastic material diaphragm 3 is provided across an upper support portion 1 on a vehicle body side and a lower support portion 2 on a cart side disposed below the upper support portion 1. ,
A rubber support plate 24 is provided on a portion 2b for receiving and receiving the lower bead portion 3d of the diaphragm 3 in the lower support portion 2, and a portion 24A for receiving the lower bead portion 3d in the support plate 24. Is reinforced with rubber containing synthetic fiber short fibers r.

  According to a second aspect of the present invention, in the air spring for a railway vehicle according to the first aspect, the support plate 24 is a thin plate-like synthetic fiber short fiber sheet material 24a in which the fiber blending direction is aligned. It is characterized by being vulcanized while being pressed in a mounted state.

  The invention according to claim 3 is the air spring for a railway vehicle according to claim 1 or 2, characterized in that the synthetic short fiber r is formed of aramid.

  The invention according to claim 4 is the air spring for a railway vehicle according to any one of claims 1 to 3, wherein the aramid short fibers r are aligned in a fiber length range of 3 to 9 mm. It is characterized by being.

  According to the first aspect of the present invention, as will be described in detail in the section of the embodiment, the portion of the lower support portion that receives the lower bead portion of the diaphragm is reinforced with synthetic fiber short fiber-filled rubber. Abrasion wear can be reduced by reducing the friction coefficient. Therefore, even if the air spring is horizontally displaced in the left-right direction or the front-rear direction due to meandering or turning during running of a railway vehicle, the receiving part of the lower support part and the lower bead part can smoothly move relative to each other, As a result, the tensile force acting in the major axis direction is absorbed and reduced, and early damage such as abnormal wear of the diaphragm can be suppressed or avoided. As a result, the slipperiness of the sliding part between the diaphragm and the lower support part is improved without causing a decrease in strength, and early wear and wear of the lower part of the diaphragm can be suppressed or avoided, and the expected performance is prolonged. It is possible to provide an air spring for a railway vehicle that can be reliably and stably exhibited and can further improve durability.

  According to the invention of claim 2, although described in detail in the section of the embodiment, the synthetic fiber short fiber sheet material in which the compounding direction of the fibers is aligned is subjected to vulcanization treatment while pressing, so that after vulcanization The fiber blending direction is aligned radially with respect to the axial center as an air spring. Therefore, there is an advantage that the above-described effect according to the invention of claim 1 can be obtained in an economical and rational state without performing any special treatment by utilizing the rubber flow during vulcanization.

  Further, as described in claim 3, it is convenient to use aramid which is an organic fiber excellent in tensile strength, elastic modulus, and heat resistance as the material of the synthetic fiber short fiber. If the fiber length is 3 to 9 mm, the portion that receives the lower bead portion can achieve both excellent wear resistance and excellent mass productivity.

  Embodiments of a railcar air spring according to the present invention will be described below with reference to the drawings. 1 is a cross-sectional view showing a railcar suspension system, FIG. 2 is a perspective view showing an intermediate support member that is turned upside down, FIG. 3 is a cross-sectional view of a main part showing another structure of a receiving ring portion, and FIG. FIG. 5 is a partial enlarged view of the entangled net, and FIG. 6 is a characteristic table showing various performances of the conventional net fiber and air spring of the present invention.

[Example 1]
1 and 2 show a railway vehicle suspension system A. FIG. The suspension device A is configured by arranging an air spring (a railcar air spring) a, an elastic stopper c, and an elastic spring mechanism b in this order from top to bottom. The air spring a includes a circular upper support portion (also referred to as an outer cylinder) 1 as viewed in the up-down direction and an intermediate support portion ("lower support") disposed below the air spring a when attached to a vehicle body (not shown) of a railway vehicle. And an inner cylinder) 2, and a diaphragm (bellows) 3 made of rubber (an example of an elastic material) such as CR or NR provided over both 1 and 2. Has been.

  The upper support 1 includes a steel plate support seat 1a that is circular in a vertical view, a steel plate cylinder 1b that is fixed to the lower surface of the steel plate, and a vertical axis P that is fixed over the both 1a and 1b. The support shaft 1c has a ring shape that is integrated with the lower surface side of the support seat 1a outside the diameter of the cylindrical portion 1b, and is fixed so as to cover the lower side of the cylindrical upper portion 1d and the cylindrical portion 1b. It has a bottom wall portion 1e and the like. The upper seat 1d is formed in a thin film shape on the outer peripheral surface of the bottomed cylindrical portion 1b, and is formed in a thick shape on the inner side of the lower surface of the support seat 1a. Is formed. On the bottom surface of the bottom wall portion 1e, a circular plate-like sliding member 6 made of stainless steel is integrated by bonding or the like.

  The diaphragm 3 includes an upper bead portion 3a that is press-fitted into an upper corner portion formed by the support seat 1a and the cylindrical portion 1b, a disk upper portion 3b that is received by the upper seat 1d with a large area, Formed by the main body portion 3c projecting in the lateral direction, and the outer peripheral surface of the upper end outer peripheral wall 2a of the intermediate support portion 2 and the upper surface of the flange portion (an example of “a portion where the lower bead portion of the diaphragm is placed and received”) 2b The lower bead portion 3d is press-fitted through the attachment ring 7 to the lower corner portion. In other words, a structure in which the diaphragm 3 is fitted and attached to both the upper support portion 1 and the intermediate support portion 2 without a fastening structure such as a bolt, as in a relationship between a tire and a wheel of an automobile, a so-called “self-seal type diaphragm”. It is comprised by the air spring a which has.

  The elastic spring mechanism b is configured by interposing a first elastic body 5 that forms an annular shape when viewed in the vertical direction across the carriage-side lower pedestal part 4 and the intermediate support part 2 disposed thereabove. Yes. The lower pedestal portion 4 includes a central cylindrical shaft portion 4a having an axis P, an inner diameter side portion 4b that is a portion mounted on the carriage, an outer peripheral flange portion 4c on which the first elastic body 5 is mounted, and an inner diameter side. It has an inclined peripheral portion 4d that connects the portion 4b and the outer peripheral flange portion 4c having a higher set height than the portion 4b, and is formed to have a circular shape when viewed in the vertical direction.

  That is, the lower receiving part 4 includes an outer peripheral flange part 4c that is a first annular outer peripheral wall that forms a first outer peripheral part, an inner diameter side part 4b that is a first central circular wall that forms a first central part, It is formed in a substantially deep dish shape having an upwardly extending cylindrical inclined peripheral portion 4d arranged so as to connect the flange portion 4c and the inner diameter side portion 4b. Reference numeral 4e denotes a positioning pin for a bogie (not shown), which is implanted at one place on the inner diameter side portion 4b extending to the inclined circumferential portion 4d.

  The intermediate support portion 2 includes the above-described flange portion 2b positioned on the outer peripheral flange portion 4c, a mounting inner peripheral wall 2c positioned above the inner diameter side portion 4b, a tapered peripheral wall 2d positioned above the inclined peripheral portion 4d, and It has the above-mentioned upper end outer peripheral wall 2a and is formed in a circular shape when viewed in the vertical direction. That is, the flange portion 2b that is the second annular outer peripheral wall that forms the second outer peripheral portion, the mounting inner peripheral wall 2c that is the second central circular wall that forms the second central portion, and these flange portion 2b and the mounting inner peripheral wall 2c is formed in the shape of a substantially bowl having an upwardly expanding cylindrical tapered peripheral wall 2d. As shown also in FIG. 2, reinforcing ribs 18 are integrally formed on the lower surface side of the mounting inner peripheral wall 2c at eight radial positions centering on the axis P, and a peripheral portion of the center hole 2f. Is formed thicker than the mounting inner peripheral wall 2c.

  The first elastic body 5 is made of a metal and has a laminated rubber structure in which three hard plates 8 and three upper and lower rubber layers 9 are alternately laminated in the vertical direction, and the outer peripheral flange portion 4c and the flange portion 2b. It is interposed between the top and bottom. The lowermost rubber layer 9 is integrated with the outer peripheral flange portion 4c by vulcanization, and the uppermost hard plate 8 is bolted to the flange portion 2b in an airtight manner via an O-ring (not shown). Yes.

  The elastic stopper c is a second elasticity that is placed on the intermediate support portion 2 in a state of being located inside the first elastic body 5 when viewed in the vertical direction and can receive the upper support portion 1 that is lowered more than a predetermined amount. The body 10 and the second elastic body 10 are assembled in a state of being pre-compressed up and down, and a contact member 11 and a receiver for locking the contact member 11 to the intermediate support portion 2 while restricting its upward movement. And a stop ring 12. The substantially support-shaped intermediate support member 2 has a relative height relationship in which the placement inner peripheral wall 2c and the outer peripheral flange portion 4c slightly interfere in the vertical direction when assembled as shown in FIG. Accordingly, when the diaphragm 3 is in an airless state and the load of the railway vehicle directly acts on the elastic stopper c, the relative height relationship in which the mounting inner peripheral wall 2c and the outer peripheral flange portion 4c clearly interfere in the vertical direction. become.

  The second elastic body 10 is made of metal and has a laminated rubber structure in which four hard plates 13 and three upper and lower rubber layers 14 are alternately laminated in the vertical direction. The upper and lower hard plates 13 and 13 have an inner diameter substantially equal to that of the rubber layer 14, but the two upper and lower hard plates 13 and 13 have an inner diameter larger than the inner diameter of the rubber layer 14 and an outer diameter smaller than the outer diameter of the rubber layer 14. Equipped in a buried state with The ring-shaped receiving ring 12 is fixed to the flat top surface 2e of the tapered peripheral wall 2d using a plurality of bolts 15 so as to be removable. The contact member 11 includes a central wall 11a that covers the upper surface of the second elastic body 10, a locking flange 11b having a diameter that interferes with the receiving ring 12, and a side peripheral wall that connects the central wall 11a and the locking flange 11b. It is formed in a deep dish shape having 11c.

  In order to assemble the elastic stopper c, the second elastic body 10 is placed on the placement inner peripheral wall 2c, and the contact member 11 is covered thereon so as to cover it. Then, the receiving ring 12 is dropped through the contact member 11 to be positioned on the locking flange 11b, and in this state, a plurality of bolts 15 are screwed onto the intermediate support member 2 and tightened. The intermediate support member 2 can be equipped with the second elastic body 10 compressed up and down by a predetermined amount. In the assembled state, the first elastic body 5 and the second elastic body 10 are set so as to substantially overlap the height of the first elastic body 5 in the vertical direction, and the elastic spring mechanism b in a compact state in the vertical direction. And an elastic stopper c.

  On the upper surface of the center wall 11a of the contact member 11, a circular flat plate-like sliding member 16 made of a low friction material such as fluororesin is integrated by means such as adhesion, and this sliding member 16 and the plate-like sliding member are integrated. A sliding mechanism e is constituted by the member 6. In other words, the sliding mechanism e is a sliding member made of a low friction material on either the upper surface of the contact member 11 or the lower surface of the bottom wall portion 1e that is the portion facing the upper wall portion 4a in the vertical direction of the upper support portion 1. Each of the members 16 is provided with a plate-like sliding member 6 having a flat surface on the sliding member side on either side.

  Next, the low friction mechanism 19 will be described. As shown in FIGS. 3 and 7, the attachment ring 7 is integrated with a support steel plate 23 made of a pressed steel plate placed on the flange portion 2b of the intermediate support portion 2 and vulcanization adhesion or the like on the upper surface side thereof. And an annular rubber (an example of a rubber support plate) 24. The annular rubber 24 is SBR (styrene butadiene rubber) or NR formed in a shape that fits into the lower bead portion 3d, and its upper surface portion 24A is made of aramid short fiber-containing rubber, that is, composite rubber. Is formed. That is, the upper surface portion 24A, which is a portion for receiving the lower bead portion 3d in the annular rubber 24, is reinforced with synthetic rubber short fiber-containing rubber, and by providing the composite rubber portion 24A, the intermediate support portion 2 and the diaphragm 3 A low friction mechanism 19 for reducing friction is configured.

  The method of making the composite rubber portion 24A is as follows. That is, the composite raw material 24a is processed in a sheet shape and its short fiber orientation direction is aligned in a certain direction, that is, an annular shape shown in "molded state" in FIG. That is, the composite raw material 24a is obtained by mixing the unvulcanized rubber with short aramid fibers and processing them into a sheet shape by a general rubber extruder or a calender roll or the like. Then, the composite raw material 24a is placed on the unvulcanized state of the annular rubber 24, that is, the rubber material 24g, and heated and vulcanized while being compressed (pressed) in that state, depending on the structure of the mold. The rubber is vulcanized while flowing radially from the inside to the outside. The “molded state” in FIG. 8 is depicted in an exploded perspective view in which the composite raw material 24a is positioned above the rubber material 24g. Even if the short fibers are not radially oriented, the effect of reducing the friction coefficient is sufficiently exhibited.

  As a result, as shown in “after vulcanization” in FIG. 8, the orientation direction can be changed so that the aramid fibers r are also arranged almost radially by the flow of the rubber. That is, the orientation of the aramid short fibers r can be aligned as much as possible in a radial pattern suitable for the shape of the attachment ring 7, that is, the air spring a, only by performing a general vulcanization process of vulcanizing while applying pressure. . Thereby, no matter which direction the support disk 28 is arranged, the frictional resistance of each part becomes constant, and the friction coefficient between the composite rubber 24A where the aramid fiber r is arranged (exposed) on the surface layer and the lower bead part 3d. Therefore, the durability of the lower portion of the diaphragm 3 can be satisfactorily improved and satisfactory durability can be improved.

  In the composite raw material 24a, the blending ratio of SBR, which is a polymer, aramid short fibers, and others such as carbon black was 100: 2: 81, and the length of the aramid short fibers was 6 mm. This is because when the length of the short fiber is increased (9 mm or more), the wear difference increases in the orientation direction, and when the length is shortened (3 mm or less), the wear resistance decreases. Also, if the length of the short fiber is long, the flow effect during vulcanization is small and the orientation is difficult to change.If the length is short, the flow effect is too high and the short fiber density is disturbed or the short fiber is detached from the rubber. There is a risk. For reference, examples of the physical properties of the aramid short fiber have a single fiber diameter of 12 μm, a strength of 25 g / D, a breaking elongation of 4.4%, and a thermal decomposition starting temperature of 500 ° C.

  And, in the railway vehicle suspension system having the air spring a having the friction reducing mechanism 19 according to the present invention, although not described in the characteristic table (described later) in FIG. It has been found that the upper support part 2 and the upper part of the diaphragm 3 have the same durability that no abnormalities appear, no abnormalities appear at 500,000 times with a forward / backward movement of 100 mm, and no abnormalities occur at 300,000 times with a forward / backward movement of 150 mm. It was.

  The skid mechanism 20 will be described. As shown in FIG. 1, a sliding plate 21 and an entanglement net (an example of a net-like fiber) 22 located below the upper and lower seats 1 d of the upper support portion 1 and a disk upper portion 3 b of the diaphragm 3. A side-sliding mechanism 20 consisting of The sliding plate 21 is made of donut-shaped (annular) PTFE (polytetrafluoroethylene: an example of a metal or a synthetic resin and an example of a fluororesin) and is in the form of a sheet, It is laid on the lower surface (an example of a “part that receives a diaphragm”) 1K. The sliding plate 21 is attached to the lower surface 1K of the upper seat 1d by means of bonding with an adhesive, vulcanization bonding, or non-bonding.

  As shown in FIG. 5, the entanglement net 22 is made of heat-treated polyamide fiber, polyester fiber, vinylon fiber, nylon fiber or the like, and is coated with a modified silicone resin (an example of application). Yes. And as shown in FIG. 4, the entanglement net | network 22 is formed in the net-like fiber of a sheet | seat shape with a ring shape (doughnut shape). By the modified silicone resin coating, the net 22 can be provided with such a rigidity that it is not biased by friction with the sliding plate 21. Functions and effects of the entanglement net 22 in which the net-like fibers are coated with the modified silicon resin and the skid mechanism 20 are as follows.

  That is, in the air spring a, there is a situation in which a longitudinal displacement, a vertical displacement, and a rotational displacement are simultaneously applied to the shaft center P. In that case, the required elongation (elongation rate) of the entanglement net 22 is 50% at the maximum. May reach. In such a case, a normal nylon net or a calami net has a breaking limit elongation of 50% to 60%, so that the allowable repeated elongation is about 20%, and therefore the repeated elongation is 50%. In, it is easily predicted that the conventional fiber will break. On the other hand, in the skid mechanism 20, since slip occurs favorably between the entanglement net 22 and the sliding plate 21 and between the entanglement net 22 and the disk upper part 3b, it is necessary for the fibers of the entanglement net 2 itself. Thus, it is possible to reduce the elongation and to prevent the frictional wear of the related members from occurring (or not).

  As the reticulated fibers of the entanglement net 22, a calami weave that can be deformed more than a certain amount even if a tensile force is applied in any direction of 360 degrees around the axis P is desirable. According to this, the modified silicone resin is infiltrated also between the calami-like filaments, and a long-term fiber coating can be maintained. Before coating the modified silicon resin, the network fiber is subjected to RFL (resorcin / formalin / latex) treatment, and after the modified silicone resin coating, heat treatment is performed for 10 to 30 minutes with dry air at 150 to 170 ° C. As a result, the modified silicone resin can be more firmly integrated into the mesh fiber.

  The mesh size of the mesh fiber used for the entanglement net 22 is preferably about 1 to 4 mm. This is because if the eyes are small, the modified silicone resin adheres to the entire surface and forms a single cloth, and cannot follow the deformation of the diaphragm 3, and if the eyes are large, the adhesion of the modified silicone resin is not sufficient. This is also because rubber may be partially exposed from the mesh. The shape of the mesh is not particularly limited, but if it is a hexagon, the tension applied to the net 22 (fiber) is maximized regardless of where the tension occurs in any of the three directions of XYZ. It is considered advantageous in that it does not.

  The modified silicone resin paint is a resin that is frequently used as a rust-resistant heat-resistant paint for buildings, plants, exhaust pipes, pipes, etc., and has excellent weather resistance and durability. Therefore, the entanglement net 22 coated with the modified silicone resin and the PTFE made by changing the idea of applying the recognized modified silicone resin, which is generally used for metal or wall coating, to the mesh fiber made of synthetic fiber. A side-sliding mechanism 20 configured with a pair with the sliding plate 21 is configured. As a result, the entanglement net 22 comes into contact with the sliding plate 21 and the diaphragm 3 with a low coefficient of friction. Thus, the durability of the diaphragm 3 is improved without causing early damage to the disk upper portion 3b.

  Next, the lateral stopper mechanism d will be described. The mounting inner peripheral wall 2 c is dropped downward with respect to the flange portion 2 b mounted on the first elastic body 5, and the outer peripheral flange portion 4 c on which the first elastic body 5 in the lower receiving base portion 4 is mounted. When the first elastic body 5 is deformed in a horizontal direction (lateral direction) more than specified, that is, by shear elastic deformation, by pulling up the inner diameter side portion 4b placed on the cart side. A lateral stopper mechanism d is configured in which the upper part 1A of the base part 1 and the lower part 2U of the intermediate support part 2 come into contact with each other to prevent further shear elastic deformation. Specifically, as indicated by phantom lines in FIG. 1, the lateral stopper mechanism d is configured to function by contact between the tapered peripheral wall 2d or the mounting inner peripheral wall 2c and the inclined peripheral portion 4d.

  That is, in the normal time when the air spring a is normal, as shown in FIG. 1, the air spring a is suspended by the air spring a and the elastic spring mechanism b that are connected in series in the load direction. In the airless state where air is released from the upper support portion 1, the upper support portion 1 is lowered until the plate-like sliding member 6 comes into contact with the sliding member 16, whereby the elastic stopper c and the elastic spring mechanism b are connected in series. Are connected and suspended. For example, when a railway vehicle having a bolsterless carriage travels in a curve, the diaphragm 3 is twisted, but in an airless state, the sliding mechanism e in which the sliding member 16 and the plate-like sliding member 6 move relative to each other functions and absorbs.

  In that case, if a large lateral load is applied due to a full load or the like, a high speed or a small curvature curve, etc., the first elastic body 5 of the laminated rubber structure (the elastic spring mechanism b) has a large shear elasticity. There is a risk of deformation. When the large shear elastic deformation occurs, the lateral stopper mechanism d functions to contact the tapered peripheral wall 2d or the mounting inner peripheral wall 2c with the inclined peripheral portion 4d to prevent further deformation. That is, the lateral stopper mechanism d prevents a large rolling of the railway vehicle in an airless state. Therefore, even if the airless state is caused by puncture, etc., the elastic spring mechanism b and the elastic stopper c provide a soft cushioning effect that is soft and effective, while preventing large rolls. Is possible.

  In addition, the lower cradle member 4 that is a component of the lateral stopper mechanism d has a substantially deep dish shape, and the strength and rigidity are remarkably improved as compared with a simple flat plate shape. Further, the intermediate support portion 2 formed in a substantially Ukrain shape is also rich in strength and rigidity depending on its shape. Therefore, it is possible to obtain advantages such as cost reduction, weight reduction, and durability improvement by reducing the thickness, and the railcar suspension system A improved so as to be more economical and rational. Realized successfully.

  By the way, as shown in FIG. 3, an annular rubber 17 is integrally provided on the inner peripheral surface of the receiving ring 12 by vulcanization adhesion or the like to provide an impact mitigation mechanism f, which receives the contact member 11 and the receiving member 11 in an airless state. It is advantageous to avoid the contact between the contact member 11 that is a metal material and the receiving ring 12 when the relative lateral displacement with the stop ring 12 is achieved, and to obtain a shock absorption effect and a noise prevention effect. It is. That is, the contact member 11 for pre-compressing the second elastic body 10 and the blocking member for preventing the contact member 11 from moving in the axis P direction due to the pre-compression reaction force of the second elastic body 10. The impact mitigating mechanism f is configured by interposing an elastic material such as rubber on one or both of the receiving ring 12.

  The characteristic table shown in FIG. 6 shows the characteristics of the skid mechanism 20 using the entangled net 22 according to the present invention and the skid mechanism using other mesh fibers. In other words, the test specimens of the mesh fibers are those having a radial width R of 150 mm, the conventional products 1 to 5 are not coated with the modified silicone resin paint, and the conventional products 1 to 4 are the outer periphery. It has a plurality of slits cut from the side toward the inside of the diameter (see JP 2005-199761 A). The product of the present invention is a product in which a modified silicone resin is coated on a mesh fiber made of synthetic fiber.

  That is, the conventional product 1 is one in which eight slits having a length L = 40 mm (L / R≈0.267) are formed at equal intervals in the circumferential direction on the outer peripheral portion of the mesh fiber. , Six slits having a length L = 30 mm (L / R = 0.2) are formed at equal intervals in the circumferential direction. In the conventional product 3, 10 slits having a length L = 40 mm (L / R≈0.267) are formed at equal intervals in the circumferential direction on the outer peripheral portion of the mesh fiber. Eight slits having a length L = 50 mm (L / R≈0.333) are formed at equal intervals in the circumferential direction. Durability tests are repeated to repeatedly load three types of horizontal displacement (70, 100, 150 mm) on each of the conventional products 1 to 5 and the air spring having the product of the present invention until entrainment, bias deformation or breakage occurs. The number of repetitions of horizontal displacement was measured, and the measurement results or the performance and durability of the mesh fiber and the air spring a were judged as a characteristic table shown in FIG.

As apparent from the characteristic table of FIG. 6, when the amount of forward / backward movement acting on the air spring is 70 mm, the conventional product 5 does not reach the target durability of 2.4 × 10 ⁵ (240,000 times). While winding the 1.2 × 10 ⁴ up has occurred, the 2.4 × 10 ⁵ of target endurance in conventional 1,2 entrainment does not occur. In the conventional product 3, the net fiber is biased and deformed at the position of 2.0 × 10 ⁴ before reaching the target durability count of 2.4 × 10 ^{5. In} the conventional product 4, the target durability count of 2. Breakage occurs at the slit forming site at the 5.5 × 10 ⁴ position until it does not reach 4 × 10 ⁵ . In the conventional products 1 and 2, there is no uneven deformation or breakage at the target durability of 2.4 × 10 ⁵ . On the other hand, in the product of the present invention, there was no problem with the target durability, and no abnormality occurred even at 1 × 10 ⁶ times (1 million times).

In the case where the longitudinal movement is 100 mm, the conventional product 1 is 5 × 10 ⁴ times (50,000 times), and the conventional product 2 is 4 × 10 ⁴ times (40,000 times). 6 x 10 ³ times (6000 times), 1 x 10 ⁴ times (10,000 times) for the conventional product 4 and 3 x 10 ³ times (3,000 times) for the conventional product 5 An abnormality occurred. On the other hand, in the product of the present invention, there was no problem at the target durability number (240,000 times), and no abnormality was observed even at 5 × 10 ⁵ times (500,000 times).

In the case where the forward / backward movement amount is 150 mm, the conventional product 1 is 3 × 10 ⁴ times (30,000 times), and the conventional product 2 is 2 × 10 ⁴ times (20,000 times). Product 3 is 3 × 10 ³ times (3,000 times), conventional product 4 is 4 × 10 ³ times (4,000 times), and conventional product 5 is 1 × 10 ³ times (1,000 times). ) In each case. On the other hand, in the product of the present invention, there was no problem at the target durability number (240,000 times). Incidentally, no abnormality was observed even 3 × 10 ⁵ times (300,000 times).

  Based on these comprehensive judgments, the product of the present invention stably maintains the shock absorbing performance due to the decrease in frictional resistance during horizontal displacement and the damage prevention performance of the flexible member until the target endurance number of the air spring a, that is, the endurance life is reached. It has been confirmed that it can be done. In addition, in the comprehensive judgment in FIG. 6, ◯ means that there is no entanglement, bias deformation, or breakage in any of the forward and backward movement amounts, so that the expected performance can be maintained up to the durability life of the entire air spring a, △ means that there is no performance degradation due to entrainment when the back-and-forth movement amount is 70, but when the back-and-forth movement amount is 100 or more, it means that a partial deformation or fracture has occurred until the end of the endurance life, and ▲ is until the end of the endurance life. Means that the partial deformation or fracture occurred, and x means that the expected performance was lost early due to the entrainment.

Sectional view showing the suspension system for railway vehicles The perspective view which shows the intermediate support member in the state reversed upside down Sectional view of the main part showing another structure of the receiving ring part Plan view showing entanglement net (net-like fiber) Partial enlarged view of the entanglement net in FIG. Characteristic table showing various performances of conventional and inventive mesh fibers and air springs Enlarged sectional view showing the shape and structure of the attachment ring Action diagram showing the main part of how to make an annular rubber

DESCRIPTION OF SYMBOLS 1 Upper support part 2 Lower support part 2b Lower support part lower bead part receiving part 3 Diaphragm 3d Lower bead part 24 Support plate 24A Support plate lower bead part receiving part 24a Synthetic fiber short fiber sheet material 24g Rubber material a Railway air spring r synthetic fibers short fibers vehicles (short aramid fibers)

Claims (4)

An air spring for a railway vehicle comprising a diaphragm made of an elastic material over an upper support portion on the vehicle body side and a lower support portion on a cart side disposed below the vehicle body,
A rubber support plate is disposed on a portion of the lower support portion where the lower bead portion of the diaphragm is placed and received, and a portion of the support plate that receives the lower bead portion is a rubber containing synthetic fiber short fibers. Reinforced air springs for railway vehicles.   2. The support plate is formed by vulcanizing while pressing a thin plate-like synthetic fiber short fiber sheet material in which fiber mixing directions are aligned while being placed on a rubber material. The air spring for railway vehicles as described.   The air spring for a railway vehicle according to claim 1 or 2, wherein the synthetic short fiber is formed of aramid.   The railcar air spring according to any one of claims 1 to 3, wherein the aramid short fibers have a fiber length aligned in a range of 3 to 9 mm.

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