JP2013108558A - Air spring - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an air spring capable of ensuring airtightness without complicating the structure.SOLUTION: The air spring includes: an upper-surface plate 21; a lower-surface plate 2; a cylindrical flexible member 3 disposed between the upper-surface plate 1 and the lower-surface plate 2; and an elastic mechanism 4 attached to the lower-surface plate 2. The elastic mechanism 4 has a layered structure in which an elastic material layer 11 and a hard plate 10 are alternately laminated, and a top plate 12 as a hard plate is disposed on the top part, and a seal part 20 is provided on the entire circumference of an outer circumference surface 12a of the top plate. The seal part 20 is formed as an elastic member constituting the elastic material layer 11 adjacent to the top plate 12 wraps around the outer circumferential surface 12a of the top plate 12, and a gap between the top plate 12 and the lower surface plate 2 is sealed as the seal part 20 is firmly attached to the lower surface plate 2, characteristically.

Description

  The present invention relates to an air spring used for a railway vehicle or the like.

  Conventionally, as an air spring used in a railway vehicle or the like, as shown in FIG. 5 of Patent Document 1, an upper surface plate attached to a vehicle body of a vehicle, a lower surface plate disposed on a wheel side below the upper surface plate, 2. Description of the Related Art A known example includes a rubber flexible member (bellows) provided over a lower surface plate and a laminated rubber interposed between the lower surface plate and a wheel-side support frame. The laminated rubber regulates fluctuations in the vertical direction of the vehicle body. As the laminated rubber, generally laminated rubber layers and steel plates are alternately used.

  A top plate is provided on the top of the laminated rubber, and the bottom plate is fixed to the top plate. More specifically, a bead receiving portion that fits a bead portion at the lower end of the flexible member is formed on the lower surface plate, and a through-hole through which a bolt can be inserted is formed radially inward of the bead receiving portion.

  In addition, a screw hole for screwing a bolt is formed at a position corresponding to the through hole of the bottom plate in the top plate, and the bolt is inserted into the through hole of the bottom plate with the bottom plate and the top plate joined. Then, the lower surface plate is fixed to the laminated rubber by being screwed into the screw hole of the top plate. Air is supplied to the inside of the flexible member and maintained in a pressurized state. The air spring is configured to exhibit a buffering function against a load and vibration in the vertical direction by a flexible member and a laminated rubber swelled with pressurized air.

Japanese Patent Laid-Open No. 10-288236

  As described above, since the inside of the flexible member is maintained in a pressurized state, the entire flexible member including the upper surface plate and the lower surface plate needs to be airtight. However, in Patent Document 1, since the bolt insertion hole is formed in the lower surface plate portion related to the airtightness of the flexible member, the pressurized air passes through the insertion hole from the gap between the lower surface plate and the top plate. There was a risk of leakage.

  Therefore, conventionally, an annular groove is formed in at least one of the lower surface plate and the top plate at the joint surface between the lower surface plate and the top plate, and the lower surface plate and the top plate are joined with an O-ring fitted into the annular groove portion. Therefore, the airtightness at the joint surface between the two was ensured. Thus, in order to ensure the airtightness of the flexible member, an annular O-ring groove or O-ring is required, and there is a problem that the structure of the air spring is complicated.

  In particular, since the O-ring groove requires accuracy, it takes time and effort to process it. When the O-ring groove is formed on the lower surface of the bottom plate, the O-ring groove faces downward when the air spring is assembled. Therefore, the O-ring must be temporarily fixed with grease or the like to prevent the O-ring from dropping. In other words, there was an inconvenience that workability was poor. Further, when the O-ring groove is formed on the top surface of the top plate, it is necessary to increase the thickness of the top plate by an amount corresponding to the O-ring groove, resulting in a disadvantage that the weight of the air spring increases.

  Then, in view of the said problem, in this invention, it aims at providing the air spring which can ensure airtightness, without complicating a structure.

  In order to solve the above problems, an air spring according to the present invention includes an upper plate, a lower plate, a cylindrical flexible member interposed between the upper plate and the lower plate, and an elastic mechanism attached to the lower plate. The elastic mechanism has a laminated structure in which an elastic material layer and a hard plate are alternately laminated, and a top plate that is a hard plate is arranged on the top, and a seal portion is provided on the entire circumference of the outer peripheral surface of the top plate. The seal portion is formed by an elastic material constituting an elastic material layer adjacent to the top plate wrapping around the outer peripheral surface of the top plate, and the seal portion is in close contact with the bottom plate, A gap between the lower plate and the lower plate is sealed.

  According to the above configuration, the structure of the elastic mechanism that has been used in the past is slightly changed, and the elastic material of the elastic material layer adjacent to the top plate is merely wrapped around the outer peripheral surface of the top plate, and the seal portion is provided around the outer peripheral surface of the top plate. Can be formed integrally. This makes it possible to seal the gap between the top plate and the bottom plate without using an O-ring groove and an O-ring.

  In addition, the elastic mechanism used in the present invention can be easily manufactured by using the same manufacturing method as the conventionally used elastic mechanism. That is, conventionally, in order to manufacture an elastic mechanism, a hard plate having rigidity such as a steel plate and an unvulcanized rubber constituting an elastic material layer are alternately charged in a mold, and then heated and pressed. It was manufactured. Therefore, if a smaller diameter than the conventional plate is used as the top plate, and the unvulcanized rubber flows into the space formed between the mold and the top plate, the seal portion made of the same vulcanized rubber as the elastic material layer. Can be integrally formed on the outer peripheral surface of the top plate.

  As for the specific configuration of the lower surface plate and the top plate, for example, a recess is formed on the lower surface of the lower surface plate, the top plate is formed so as to be able to fit into the recess in a state where the seal portion is formed, and the seal portion is recessed from the top plate. By fitting to, it can be set as the structure closely_contact | adhered to the upper surface in a recessed part. Further, in the above configuration, by fitting the top plate into the concave portion, the seal portion is pressed against the inner surface of the concave portion to be deformed, and the outer diameter is enlarged to be in close contact with the entire circumference of the inner peripheral surface of the concave portion. If it does in this way, the contact area of a seal part and a lower surface board (concave part) will increase, and a sealing performance can be improved more.

  That is, when the top plate is inserted into the recess, the seal portion abuts against the lower surface of the lower surface plate (the inner upper surface of the recess). Further, by pressing the inner upper surface of the recess against the seal portion, the seal portion is elastically deformed and the outer diameter is expanded. As a result, the seal portion is in close contact with not only the inner upper surface of the recess but also the inner peripheral surface of the recess, and the contact area between the seal portion and the recess can be increased.

  Furthermore, in the above configuration, since the seal portion is fixed so as not to be displaced in the horizontal direction, deterioration due to repeated displacement of the seal portion can be suppressed, and durability as an air spring can be improved. Become. In the present invention, the deformed seal portion may be in close contact with the entire circumference of the inner peripheral surface of the recess. Therefore, even if the seal portion is not in close contact with the entire inner peripheral surface, for example, only the upper portion of the inner peripheral surface of the recess may be in close contact over the entire periphery.

  In order for the seal portion to abut against and press against the lower surface of the lower surface plate or the upper surface of the recess, the upper end portion of the seal portion can be formed to protrude from the upper surface of the top plate. At this time, the lower surface of the lower surface plate or the upper surface in the recess may be formed in a planar shape. In addition, the upper end of the seal portion may be formed so as to be flush with the upper surface of the top plate, and the portion that contacts the seal portion on the lower surface of the lower surface plate or the upper surface in the recess may be formed so as to protrude toward the seal portion side. Is possible. In other words, the shape of the seal portion and the bottom plate may be such that one of them protrudes from the shape in contact with each other without any gap to the other side.

  The air spring of the present invention described above is characterized in that the elastic material constituting the elastic material layer adjacent to the top plate wraps around the outer peripheral surface of the top plate, but is not limited thereto. In the top plate, the seal portion can be formed so as to go from the outer peripheral surface to the upper surface. In this way, the elastic material of the elastic material layer adjacent to the top plate is made to wrap around the top plate through the outer peripheral surface of the top plate, whereby the seal portion can be integrally formed on the entire periphery of the top plate. According to the above configuration, the seal portion can be reliably sandwiched between the lower surface of the lower plate and the upper surface of the top plate, and the gap between the top plate and the lower plate can be sealed.

  Even in this case, a recess is formed on the lower surface of the lower surface plate, the top plate is formed so as to be able to fit into the recess in a state where the seal portion is formed, and the seal portion is formed by fitting the top plate into the recess, The contact area between the seal part and the bottom plate (concave part) is adopted by adopting a structure that is pressed against the inner surface of the concave part and deforms, and the outer diameter expands and adheres to at least a part of the inner peripheral surface of the concave part. And the sealing performance can be further improved.

  In the air spring of the present invention, it is preferable to perform chamfering or R processing on the upper end portion and the lower end portion of the outer peripheral surface. In other words, the greater the angle of the corners (upper end and lower end) of the outer peripheral surface of the top plate, the less the occurrence of cracks and delamination starting from the elastic material part in contact with the corners, thereby improving the durability of the air spring. Can be made. Note that the entire outer peripheral surface can be a curved surface.

  In the present invention, since the elastic material constituting the elastic material layer adjacent to the top plate is wrapped around the entire circumference of the outer peripheral surface of the top plate of the elastic mechanism, the seal portion is formed. With the configuration, it is possible to seal the gap between the top plate and the bottom plate.

The longitudinal cross-sectional view which shows embodiment of the air spring of this invention The expanded sectional view which shows the lower surface board and elastic mechanism of FIG. 2 is an enlarged cross-sectional view of the main part of FIG. The principal part expanded sectional view which shows the 2nd aspect of a seal part The principal part expanded sectional view which shows the 3rd aspect of a seal part The principal part expanded sectional view which shows the 4th aspect of a seal part The principal part expanded sectional view which shows the 5th aspect of a seal part

  Hereinafter, embodiments of the present invention will be described with reference to the drawings. 1-3 is a figure which shows embodiment of the air spring for railway vehicles which concerns on this invention. 1 is a longitudinal sectional view of an air spring, FIG. 2 is an enlarged sectional view showing an elastic mechanism of FIG. 1, and FIG. 3 is an enlarged sectional view of a main part of a seal portion.

  The air spring includes an upper surface plate 1 attached to the vehicle body of the vehicle, a lower surface plate 2 disposed below the wheel, and a cylindrical flexible member 3 interposed between the upper surface plate 1 and the lower surface plate 2. And an elastic mechanism 4 interposed between the lower surface plate 2 and the support frame on the wheel side.

  In the present embodiment, a rubber bellows is used as the flexible member 3. The flexible member 3 is composed of a laminated rubber having a reinforcing rubber layer in which a reinforcing cord is embedded as an intermediate layer, and the flexible member 3 has a wall thickness in which a reinforcing rubber layer is wound around a bead core at an upper end portion and a lower end portion thereof. Bead portions 3a and 3b are formed.

  As shown in FIG. 1, the upper surface plate 1 includes a metal disk-shaped support plate 5, a cylindrical bead receiving portion 6 that protrudes toward the lower surface plate at the center of the support plate 5, and the support plate 5. And a protective rubber layer 7 provided on the lower surface of the bead receiving portion 6 on the outer side in the radial direction.

  As shown in FIG.1 and FIG.2, the lower surface board 2 is formed in a disk shape with a metal material. A cylindrical bead receiving portion 8 that protrudes toward the upper surface plate 1 is formed at the center of the lower surface plate 2, and a flange portion 9 is formed radially outward from the bead receiving portion 8.

  The elastic mechanism 4 has a laminated structure in which annular hard plates 10 and annular elastic material layers 11 are alternately laminated. A top plate 12, which is a hard plate, is disposed on the top of the elastic mechanism 4, and a base 13 serving as a hard plate supported by the support frame is disposed on the bottom of the elastic mechanism 4. In this embodiment, a metal plate is used as the hard plate, and a rubber material is used as the elastic material layer.

  The lower surface plate 2 is fixed to the top plate 12 by a fixing member 14. Specifically, as shown in FIG. 2, a recess 15 is formed on the lower surface of the lower surface plate 2 at a position that overlaps the bead receiving portion 8. The recess 15 is formed so as to open downward, and a through-hole 16 penetrating the inner upper surface 15 a of the recess 15 and the bead receiving portion 8 is formed. In the present embodiment, a rod screw 17 that is a male screw and a nut 18 that is a female screw that is screwed to the rod screw 17 are used as the fixing member 14. The bar screw 17 projects from the top plate 12 at a position corresponding to the through hole 16 of the bottom plate.

  The through hole 16 is formed in a shape that can accommodate the nut 18. That is, the through hole 16 has a stepped structure in which a concave storage portion capable of storing the nut 18 is formed in the bead receiving portion 8 and a hole having a smaller diameter than the storage portion is formed in the center of the storage portion. When the lower surface plate 2 is fixed to the top plate 12, the bar screw 17 may be engaged with the small diameter hole of the through hole 16, and the nut 18 may be screwed to the tip of the bar screw 17. Thereby, the nut 18 can be stored in the storage portion of the through hole 16.

  A rubber seat 19 is installed on the surface of the flange portion 9. The rubber seat 19 is formed in a ring shape and is fitted into the bead receiving portion 8 of the bottom plate. The bead portion 3 b at the lower end of the flexible member 3 is fitted into the bead receiving portion 8 in a state where the rubber seat 19 is disposed on the surface of the flange portion 9.

  In the present invention, as shown in FIG. 3, the seal portion 20 is formed on the top plate outer peripheral surface 12a (portion indicated by a thick line in the figure). The seal portion 20 is formed by causing an elastic material constituting the elastic material layer 11 adjacent to the top plate 12 to wrap around the top plate outer peripheral surface 12a. In the present embodiment, the sealing portion 20 is formed with a protruding portion 20a so that the upper end portion protrudes from the top plate upper surface 12b. On the other hand, the concave upper surface 15a is formed in a planar shape. Here, the top plate upper surface 12b is a surface that comes into contact with the inner surface 15a of the recess when the top plate 12 in a state where the seal portion 20 is not formed is fitted into the recess 15, and is arranged at the radially outer end of the top plate upper surface 12b. A top plate outer peripheral surface 12a is provided continuously.

  Further, chamfering is performed on both upper and lower end portions of the top plate outer peripheral surface 12a. Thus, an upward inclined surface and a downward inclined surface are respectively formed at the upper end portion and the lower end portion of the top plate outer peripheral surface 12a, and the seal portion 20 is formed on the entire outer peripheral surface including these inclined surfaces. The top plate 12 is formed so that the outer diameter thereof is slightly smaller than the inner diameter of the recess 15 in a state where the seal portion 20 is formed.

  In the above configuration, when the top plate 12 is fitted into the recess 15 while the through hole 16 of the lower surface plate is engaged with the bar screw 17 projecting from the top plate 12, the protruding portion 20a of the seal portion abuts against the upper surface 15a of the recess. . In this state, when the nut 18 is screwed into the tip of the rod screw 17 and tightened, the upper surface 15a in the recess and the top plate 12 approach each other.

  Thereby, the protrusion 20a is elastically deformed so that the outer diameter of the seal portion 20 is expanded by being pushed into the inner surface 15a of the recess. At this time, the upward inclined surface of the top plate outer peripheral surface 12a assists the elastic material constituting the protruding portion 20 to be smoothly deformed outward in the radial direction of the top plate. When the tightening of the nut 18 is completed, the inner surface 15a of the concave portion comes into contact with the top surface 12b of the top plate, and the seal portion 20 is disposed around the inner surface 15a of the concave portion and the inner peripheral surface 15b of the concave portion so as to surround the through hole 16. Adhere strongly. As described above, the seal portion 20 seals the gap between the top plate 12 and the bottom plate 2 to prevent air leakage in the flexible member 3.

  In the present embodiment, the aspect in which the seal portion 20 is formed on the top plate outer peripheral surface 12a has been described. However, the present invention is not limited to this. For example, as shown in FIG. 4, the top plate 12 may wrap around from the outer peripheral surface 12a to the upper surface 12b. It is also possible to form it. In this case, when the seal portion 20 is pressed by the recess inner upper surface 15a, the seal portion 20 portion formed on the top plate upper surface 12b is sandwiched between the recess inner upper surface 15a and the top plate upper surface 12b, and the seal portion 20 and the recess inner upper surface are sandwiched. The sealing property with 15a can be improved. Furthermore, if the seal portion 20 is elastically deformed and is in close contact with the entire circumference of the concave inner peripheral surface 15b, the contact area between the seal portion 20 and the lower surface plate 2 increases, and the sealing performance can be further improved.

  In the aspect in which the seal portion 20 is formed in the top plate 12 so as to wrap around from the outer peripheral surface 12a to the upper surface 12b, in order to further improve the sealing performance of the seal portion 20, for example, as shown in FIG. It is also possible to form an annular groove 21 in the inner wall and cover the annular groove 21 with the seal portion 20. Thereby, the sealing performance of the seal part 20 and the top plate 12 can be further improved.

  In addition, as shown in FIG. 6, it is also possible to further form an annular convex portion 22 in the seal portion 20 portion formed on the top plate upper surface 12b. As a result, the pressure received from the inner surface 15a of the concave portion is concentrated on the annular convex portion 22, whereby the sealing performance between the upper surface 15a of the concave portion and the seal portion 20 can be further enhanced. Needless to say, the annular groove 21 can be formed in the outer edge portion of the top plate upper surface 12 b, and the annular convex portion 22 can be formed in the seal portion 20.

  Further, in the aspect in which the seal portion 20 is formed on the outer peripheral surface 12a of the top plate, the upper end of the seal portion 20 is flush with the upper surface of the top plate 12 without providing the protruding portion 20a in the seal portion 20 as shown in FIG. It is also possible to form the portion in contact with the seal portion 20 on the inner surface 15a of the recess so as to be inclined so as to project toward the seal portion side. In this aspect, the inclined surface 23 is provided on the inner surface 15a side of the recess, and the upward inclined surface corresponding to the inclined surface 23 is also provided on the outer peripheral surface of the top plate. As a result, the inner surface 15a in the recess can be strongly pressed against the seal portion 20. Furthermore, the seal part 20 can be elastically deformed to increase the outer diameter of the seal part 20, and the seal part 20 can be brought into close contact with the entire circumference of the concave inner peripheral surface 15b.

DESCRIPTION OF SYMBOLS 1 Upper surface board 2 Lower surface board 3 Flexible member 4 Elastic mechanism 5 Support plate 6, 8 Bead receiving part 7 Protective rubber layer 9 Flange part 10 Hard board 11 Elastic material layer 12 Top plate 12a Top plate outer peripheral surface 12b Top plate upper surface 13 Base 14 Fixing member 15 Recess 15a Recess inner surface 15b Recess inner peripheral surface 16 Through hole 17 Bar screw 18 Nut 19 Rubber seat 20 Seal part 20a Protruding part 21 Annular groove 22 Annular convex part

Claims (6)

An upper surface plate, a lower surface plate, a cylindrical flexible member interposed between the upper surface plate and the lower surface plate, and an elastic mechanism attached to the lower surface plate, the elastic mechanism comprising an elastic material layer and a hard plate Are stacked alternately, and a top plate which is a hard plate is arranged on the top, a seal portion is provided on the entire outer periphery of the top plate, and the seal portion is elastic adjacent to the top plate. The elastic material constituting the material layer is formed by wrapping around the outer peripheral surface of the top plate, and the seal portion is in close contact with the lower surface plate to seal a gap between the top plate and the lower surface plate. Air spring. A recess is formed on the lower surface of the lower surface plate, and the top plate is formed so as to be able to fit into the recess in a state where the seal portion is formed, and the seal portion fits the top plate into the recess. The air spring according to claim 1, wherein the air spring is in close contact with the upper surface in the recess. The seal portion is pressed and deformed by fitting the top plate into the recess, and is deformed by being pressed against the inner upper surface of the recess, and the outer diameter is enlarged to closely contact the entire circumference of the inner peripheral surface of the recess. The air spring according to claim 2. The air spring according to any one of claims 1 to 3, wherein the seal portion is formed so that an upper end portion protrudes from an upper surface of the top plate. The air spring according to claim 1, wherein the seal portion is formed so as to wrap around from the outer peripheral surface to the upper surface of the top plate. The air spring according to any one of claims 1 to 5, wherein chamfering processing or R processing is performed on an upper end portion and a lower end portion of the outer peripheral surface.

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