JP2019108919A - Air spring - Google Patents

Abstract

To provide an air spring capable of improving pressure resistance and horizontal allowable displacement performance.SOLUTION: A cylindrical diaphragm 5 is disposed between an upper face plate 2 and a laminated rubber 3 and a stopper 4. An upper bead portion 6 projecting to an inner face side, is disposed on an upper end portion of the diaphragm 5. The neighborhood of an end portion of an outer face of the diaphragm 5 is closely brought into contact with the upper face plate 2. The upper bead portion 6 is fitted to a connection portion 7 projected at a center of the upper face plate 2. A bead presser 8 is vertically holding the upper bead portion 6 with the upper face plate 2, is disposed. The bead presser 8 is provided with a locking projection 9 for locking the upper bead portion 6 from a radial outer side.SELECTED DRAWING: Figure 1

Description

  The present invention relates to an air spring having a cylindrical diaphragm interposed between an upper member and a lower member and installed in, for example, a railway vehicle, an automobile, or various industrial machines.

  Generally, an air spring mounted on a railway vehicle or the like has a structure in which a diaphragm made of a cylindrical rubber film is interposed between an upper member and a lower member, and the upper and lower ends of the diaphragm are the upper member and the lower member. (See, for example, Patent Document 1).

  In the air spring of Patent Document 1, the bead portion (fitting portion) 103 of the diaphragm 102 is fitted and coupled to the fitting portion 101 of the lower member thereof. The air spring is designed to be coupled with a final predetermined fitting force by sealing the air after the bead portion 103 is fitted and coupled to the fitted portion 101 (see FIG. 3).

Unexamined-Japanese-Patent No. 2001-355667 (Paragraphs 0002-0005, FIG. 3 (a)).

  However, although the air spring of Patent Document 1 shown in FIG. 3 has a structure to increase the bonding force between the bead portion and the fitting portion by applying an appropriate air pressure, when the air pressure is excessively increased, When the diaphragm expands in the radial direction by the air pressure, the bead portion expands in diameter to form a gap with the fitting portion, which may cause air leakage from the gap.

  Further, as shown in FIG. 4, when the upper member 104 and the lower member 105 are relatively horizontally displaced to the left and right, a shearing force acts on the cylindrical diaphragm 106, and along with this shearing force, Tensile stress (σ1) and compressive stress (σ2) act diagonally on the rubber film. In particular, when the tensile stress (σ1) is large and the horizontal displacement is excessively large in the right side portion in FIG. 4, the entire upper bead portion 107 is inclined to shift obliquely downward to the right end portion of the bead portion 107. (S1) is generated. This shift (S1) may cause a gap between the upper member 104 and the bead portion 107, and air may leak from the gap.

  Further, the horizontal displacement of the upper member 104 and the lower member 105 makes the heights (h1, h2) of the diaphragm 106 different from each other. Furthermore, even if the diaphragm 106 is deformed, the same tensile force in the generatrix direction per unit width acting on the rubber film of the diaphragm 106 is substantially equal to the height (h1, h2) by acting the same air pressure on the entire inside. It will be proportional. Thus, when the horizontal displacement is excessively large, the entire bead portion 107 is pulled rightward in FIG. 4 to cause a rightward shift (S2) in the right end portion of the bead portion 107. This deviation (S2) may cause a gap between the upper member 104 and the bead portion 107, and air may leak from the gap.

  Furthermore, the displacement in each direction of the bead portion as described above depends on the dimensions of the diaphragm, the size of the air pressure, and the size of the horizontal displacement, and the respective displacement amounts change, and the displacement in each direction is combined. Therefore, the bead portion tends to be largely displaced in various directions. Thereby, when excessive air pressure acts or excessive horizontal displacement, a gap is formed between the bead portion of the diaphragm and the upper member or the lower member, and air leaks from the gap. There is a fear.

  An object of the present invention is to provide an air spring capable of improving pressure resistance and horizontal allowable displacement performance.

  In order to achieve the above object, an air spring according to the present invention has a cylindrical diaphragm interposed between an upper member and a lower member, and a bead portion which protrudes to the inner surface at the end of the diaphragm And press-fit the seal portion of the outer surface of the diaphragm to the upper member or the lower member, and the bead portion is fitted to a connecting portion projecting from the center of the upper member or the lower member. Further, a bead presser for holding the bead portion between the upper side member and the lower side member vertically is provided, and a locking projection for locking the bead portion from the radial direction outer side is formed on the bead presser.

  According to the above configuration, since the bead portion is vertically sandwiched by the bead pressing and the upper member or the lower member, it is possible to restrict the deformation of the bead portion in the vertical direction. Furthermore, since the bead portion is locked from the radial direction outer side by the locking protrusion formed on the bead presser, the bead portion is radially interposed between the locking protrusion and the connecting portion of the upper member or the lower member. It is possible to restrict the radial deformation of

  Thereby, it is possible to regulate the deformation of the bead part in all directions, and even if the air pressure of the air spring is increased or the horizontal displacement is largely made, the deformation of the bead part in any direction is thereby prevented. The pressure resistance and the horizontal allowable displacement performance of the air spring can be improved.

  Further, the outer peripheral surface of the connecting portion may be formed in a tapered shape.

  According to this configuration, since the connection portion is tapered, the bead portion can be strongly pressed against the connection portion and sealed by pressing the bead portion by air pressure, and the connection between the connection portion and the bead portion is a so-called self seal type. be able to.

  In this case, after the bead portion is pressed into contact with the upper member or the lower member, the bead portion can not be further pressed into contact with the connecting portion, and the bead portion can be made by excessively increasing the air pressure. There is a possibility that the sealability may deteriorate due to the diameter expansion. On the other hand, by adopting the configuration of the present invention, it is possible to prevent the diameter expansion of the bead portion and prevent the decrease in sealability, and while adopting the self-seal type, the pressure resistance and the horizontal tolerance of the air spring. Displacement performance can be improved.

  Further, a stopper receiver and a stopper may be formed on the upper member and the lower member, respectively, for limiting the downward displacement of the upper member, and a bead presser may be formed on the outer periphery of the stopper receiver or the stopper.

  According to this configuration, since the bead presser is formed on the outer peripheral portion of the stopper receiver or the stopper, a dedicated part as the bead presser can be omitted, and the number of parts can be reduced accordingly.

  As described above, according to the present invention, the bead presser is provided, and the bead portion is vertically sandwiched by this and the upper member or the lower member, and further, the locking projection is formed on the bead presser to radially outside the bead portion. It is locked from the As a result, it is possible to prevent the bead portion from being deformed in any direction due to excessive air pressure or large horizontal displacement, and the pressure resistance and the allowable horizontal displacement performance of the air spring can be improved.

Cross-sectional view of an air spring according to the present invention Enlarged cross section near the bead Cross-sectional view of a conventional air spring Diagram showing horizontal displacement of a conventional air spring

  Hereinafter, an embodiment of an air spring according to the present invention will be described using the drawings.

  As shown in FIG. 1, the air spring 1 is provided, for example, on a railway vehicle, and is laminated, for example, on the upper surface plate 2 as an upper member attached to the vehicle body side and, for example, as a lower member attached to a truck side Between the rubber 3 and the stopper 4, a cylindrical diaphragm 5 is interposed, and an upper bead portion 6 projecting to the inner surface side is provided at the upper end portion of the diaphragm 5, and a seal portion of the outer surface of the diaphragm 5 And the upper bead portion 6 is fitted into the connecting portion 7 projecting downward from the center of the upper surface plate 2, and further, the upper bead portion 6 is vertically moved between the upper surface plate 2 and the upper surface plate 2. A bead presser 8 is provided, and a locking projection 9 is formed on the outer peripheral edge of the bead presser 8 for locking the upper bead portion 6 from the outer side in the radial direction.

  The upper surface plate 2 is made of, for example, steel and is in the shape of a disc whose peripheral edge is bent downward, and the cylindrical boss 10 fitted in the central circular hole engages, for example, the vehicle side. The air supply port is used to supply air to the inside of the diaphragm 5.

  On the lower surface side of the central portion of the upper surface plate 2, a connecting portion 7 is provided so as to project downward so as to surround the boss portion 10, and the upper bead portion 6 of the diaphragm 5 is fitted to the connecting portion 7. The connecting portion 7 is formed into a large diameter and tapered cylindrical shape, the outer peripheral surface thereof is formed into a tapered shape, and the air pressure inside the diaphragm 5 pushes the upper bead portion 6 to seal between the connecting portion 7 and the self It constitutes a seal.

  A disc-like stopper receiver 11 is attached to the lower side of the connecting portion 7 so as to cover the space between the connecting portion 7 and the boss portion 10, and the stopper receiver 11 contacts the stopper 4. It is designed to regulate downward displacement.

  The outer peripheral portion of the stopper receiver 11 is a bead presser 8, and the upper bead portion 6 of the diaphragm 5 is vertically sandwiched between the bead presser 8 and the upper surface plate 2. The stopper receiver 11 is, for example, formed of a plurality of sector-shaped divided bodies configured in a disc shape as a whole, and is configured in a disc shape inside the diaphragm 5 while bolting each split body to the upper surface plate 2 Ru.

  An annular locking projection 9 is formed on the outer peripheral edge of the bead presser 8 so as to expand upward in a substantially semicircular shape in cross section, and the upper bead portion 6 is locked from the radial direction outer side. The upper bead portion 6 of 5 is interposed in the radial direction.

  The laminated rubber 3 has a structure in which a plurality of doughnut-shaped rubbers and steel plates are alternately stacked, and a stopper 4 is bolted on the upper side thereof.

  The stopper 4 is, for example, a thick plate made of aluminum, and the lower portion of the outer peripheral portion thereof protrudes radially outward to constitute the bead sheet 12. The lower bead portion 13 of the diaphragm 5 is fitted to the stopper 4 so as to press it in contact with the bead sheet 12 and the lower bead portion 13 adheres to the tapered side peripheral surface of the stopper 4 and self-seals It is supposed to be.

  The diaphragm 5 has a structure in which a reinforcing cord or the like is embedded in a tubular rubber film to be reinforced, and the upper bead portion 6 and the lower bead portion 13 thicker than the center side are held by the connecting portion 7 and the stopper 4 Being sealed. The diaphragm 5 is filled with air at the inside, pushed downward at the lower end, and elastically supports the load that the top plate 2 receives from the vehicle body side, for example, by the air pressure inside.

  According to the above configuration, the upper bead portion 6 is vertically sandwiched between the upper surface plate 2 and the bead presser 8 and radially interposed between the connecting portion 7 and the locking projection 9, so all directions of the upper bead portion 6 It is possible to prevent the air leakage due to the displacement of the upper bead portion 6 and the formation of a gap.

  That is, as shown in FIG. 2, when the air spring 1 is displaced horizontally, the upper bead portion 6 tends to be displaced in the d1 direction by the shear force acting on the diaphragm 5, and the deformation of the diaphragm 5 causes the sum of the air pressures in the left and right portions. The upper bead portion 6 tends to be displaced in the d2 direction due to the occurrence of an imbalance in the Also, even when the air pressure is increased more than usual, the upper bead portion 6 tends to be displaced in the d2 direction due to the diameter increase.

  Furthermore, the displacement in the d1 direction and the displacement in the d2 direction are combined, and the upper bead portion 6 tends to be displaced in the d3 direction, and the d3 direction is d2 from the d1 direction depending on the dimensions of the diaphragm 5 and the air pressure. Change between directions.

  On the other hand, since the bead presser 8 and the locking projection 9 are provided to restrict the displacement of the upper bead portion 6 in all directions, the upper side of the upper bead portion 6 is to be displaced in any direction d3 By restricting the displacement of the bead portion 6, air leakage due to the formation of a gap can be prevented.

  Here, the height (L) of the locking projection 9 may be appropriately set in accordance with various conditions, but for practical purposes, the height (L) of the connecting portion 7 should be 1/3 or more. Good (L> L0 / 3).

  In addition, this invention is not limited to said embodiment, A change can be suitably added within the scope of the present invention. For example, instead of providing the bead press 8 and the locking projection 9 on the side of the upper surface plate 2, the bead press 8 and the locking projection 9 may be provided on lower members such as the laminated rubber 3 and the stopper 4 A bead presser 8 and a locking projection 9 may be provided. Moreover, the connection part 7 may not only form the outer peripheral surface into a taper shape, but may form it into a straight form. Further, not only the outer peripheral portion of the stopper receiver 11 may be used as the bead presser 8, but a dedicated bead presser 8 and a locking projection 9 may be provided.

1 Air spring 2 Upper plate (upper member)
3 Laminated rubber (lower side member)
4 Stopper (lower member)
Reference Signs List 5 diaphragm 6 upper bead portion 7 connecting portion 8 bead presser 9 locking projection 10 boss portion 11 stopper receiver 12 bead sheet 13 lower bead portion

Claims (3)

An air spring comprising a cylindrical diaphragm interposed between an upper member and a lower member, the air spring comprising:
The diaphragm is provided at its end with a bead that protrudes to the inner surface, and the seal on the outer surface is pressed against the upper member or the lower member, and the bead is at the center of the upper or lower member. Fitted in the connection part protrusively
A bead presser is provided which sandwiches the bead portion between the upper member and the lower member, and a locking projection for locking the bead portion from the radial direction outer side is formed on the bead presser. And an air spring.   The air spring according to claim 1, wherein the connecting portion is formed in a tapered shape on an outer peripheral surface thereof.   The upper member and the lower member are respectively provided with a stopper receiver and a stopper for limiting the downward displacement of the upper member, and the bead retainer is formed on the outer periphery of the stopper receiver or the stopper. The air spring according to claim 1 or 2.

Images