JP5427920B2 - Axle spring for vehicle - Google Patents

Description

  The present invention relates to a shaft spring device used for railway vehicles, trucks, industrial vehicles, and the like, and more specifically, a plurality of elastic layers between a main shaft and an outer cylinder having the same or substantially the same axis. The present invention relates to a vehicular shaft spring in which an elastic portion of a laminated rubber structure is provided in which a hard rubber partition and a hard partition wall are alternately laminated concentrically or substantially concentrically with each other in the radial inner and outer directions.

  As a vehicle using this type of shaft spring, a rail vehicle disclosed in Patent Document 1 is known. That is, as shown in FIG. 2 of Patent Document 1, it is a means for suspending and supporting the axle box 27 that supports the axle on the bogie frame 28, and is arranged one by one in front and rear of the axle box in a vertically oriented posture. It is built into the trolley.

  In this shaft spring, the rubber of the elastic portion is a cushion spring, and also has a damper (attenuation) function, albeit slightly, due to the viscosity of the rubber. In other words, railway carts employ a suspension structure using a shaft spring when high damping performance is not required. The shaft spring used in the railway carriage is a shaft spring having a cross-sectional shape such as an elastic portion, that is, a conical laminated rubber structure.

  If you want to have a high damping performance in a truck with a structure using a shaft spring, first consider using a so-called “high damping rubber” for the rubber that constitutes the elastic layer of the elastic part. It is done. However, if the damping property of the rubber is increased, the required creep performance can no longer be satisfied, and if the creep performance is satisfied, the damping performance deteriorates. This is difficult to implement.

  In view of this, there can be considered a means in which the main shaft is formed in a hollow cylindrical shape (see FIGS. 3 and 4 of Patent Document 1), and a damper mechanism is provided using the space of the hollow portion. For example, a damper mechanism having a configuration in which a hollow portion is formed in a cylinder and a damping fluid such as hydraulic oil is placed therein, and a piston with an orifice that slides in the axial direction in the cylinder is supported on the outer cylinder side. Conceivable. However, this means complicates the structure, increases the number of parts, increases the weight, and increases the cost.

In addition, as disclosed in Patent Document 2 (see FIG. 1 and the like) and Patent Document 3 (see FIGS. 1 and 3), means for attaching a separate damper device to the shaft spring is also conceivable. This means avoids the “complexity of the structure” as a shaft spring, but requires a separate arrangement space, and the problems of weight increase and cost increase still remain. Accordingly, there remains room for further improvement in the realization of the vehicle shaft spring having high damping performance.
JP 2002-295584 A JP 2001-063567 A JP 2006-281969 A

  An object of the present invention is to realize and provide a vehicle-use shaft spring with a simple damper that does not require a dedicated arrangement space while further reducing the increase in the number of parts and the cost increase by further structural improvements. It is in.

In the invention according to claim 1, a plurality of elastic layers 4 and hard partition walls 5 are concentric with the shaft center P or between the main shaft 1 and the outer cylinder 2 having the same or substantially the same shaft center P. In the vehicular shaft spring in which the elastic part 3 of the laminated rubber structure is alternately laminated in the radially inner and outer directions in a substantially concentric state,
The outer cylinder 2 having a C-shaped cross section is arranged close to the small diameter side of the main shaft 1 in the direction along the axis P,
The elastic portion 3 is arranged close to the main shaft 1 on the small diameter side in the direction along the axis P, and the elastic portion 3 is arranged on the elastic portion 3 in the direction along the axis P. On the other hand, it is arranged close to the small diameter side, and has a shaft spring portion a having a conical laminated rubber structure in which a cross-sectional shape in the direction along the axis P is formed in a C shape,
The main shaft 1 is formed as a cylindrical member having a hollow portion 1e and penetrating in the direction of the axis P, and a stopper 10 that covers and closes the hollow portion 1e is provided on the damper chamber side of the main shaft 1 Equipped on the edge,
A damper mechanism b having a damper chamber 9 capable of expansion and contraction by relative movement between the main shaft 1 and the outer cylinder 2 in the axis P direction, and an orifice 12 communicating with the damper chamber 9. Is equipped with
The damper chamber 9 is configured by a space portion 7 surrounded by a closing portion 6 that closes one end in the axial direction of the outer cylinder 2, the main shaft 1, the plug 10, and the elastic portion 3,
A vehicle shaft spring in which the orifice 12 for communicating the hollow portion 1e and the damper chamber 9 with the stopper 10 is formed .

  According to the first aspect of the present invention, due to the expansion and contraction of the damper chamber accompanying the relative vertical movement of the main shaft and the outer cylinder, the fluid passes through the orifice communicating with the damper chamber and the outside thereof, thereby reducing the damping force (damping performance). ) Can be obtained. Since the damper chamber uses the relative movement in the axial direction between the main shaft and the outer cylinder, which are constituent elements provided originally, a special structure for expanding and contracting the damper chamber is not necessary. As a result, by further structural improvements, an increase in the number of parts and an increase in cost can be minimized, and a simple axle shaft spring with a damper that does not require a dedicated arrangement space can be realized and provided. In this case, as in the first aspect, the damper chamber can employ a means configured by a space portion surrounded by a closing portion that closes one end in the axial direction of the outer cylinder, the main shaft, and the elastic portion. is there.

According to the first aspect of the present invention, there is an advantage that the main shaft having a hollow portion communicating with the outside, that is, the main shaft of the current product can be used as it is without changing the design, and for that purpose, a plug provided at the upper end of the main shaft, that is, a new installation Since an orifice is also formed in the plug that is a part, there is also an advantage that a rational configuration of a multi-function plug can be realized.

Sectional drawing which shows the structure of the axial spring for vehicles by Example 1. FIG. Sectional drawing which shows the structure of the axial spring for vehicles by the reference Example 1. Sectional drawing which shows the structure of the axial spring for vehicles by the reference Example 2. Sectional drawing of the principal part which shows the 1st another structure of the elastic part in FIG. Sectional drawing of the principal part which shows the 2nd another structure of the elastic part in FIG. Sectional drawing of the principal part which shows another structure of the elastic membrane in FIG.

  Hereinafter, an embodiment of a shaft spring for a vehicle according to the present invention will be described with reference to the drawings when used for suspension in a bogie of a railway vehicle. FIG. 1 is a cross-sectional view illustrating a vehicle shaft spring according to a first embodiment, FIGS. 2 and 3 are cross-sectional views illustrating vehicle shaft springs according to Reference Embodiments 1 and 2, and FIGS. 4 and 5 are vehicle shaft springs according to FIG. FIG. 6 is a cross-sectional view of the main part showing another structure of the vehicle shaft spring of FIG. 3.

[Example 1]
The shaft spring A for a vehicle according to the first embodiment is used for a railway bogie, and as shown in FIG. 1, an outer shaft having a main shaft 1 and a longitudinal axis P that is the same (or substantially the same) as the main shaft 1. Between the cylinder 2, the elastic layer 4 having three layers (a plurality of examples) and the hard partition wall 5 having two layers (a plurality of examples) are concentrically (or almost concentrically) with the longitudinal axis P and are radially inward / outward. The shaft spring portion a is formed by interposing the elastic portions 3 of a laminated rubber structure that are alternately laminated in the direction, and a damper mechanism b formed integrally with the upper portion of the shaft spring portion a.

  The main shaft 1 is made of metal and is formed at the lower end portion of the main shaft 1 so as to be fixed to the casing of the axle. Threaded portion) and a cylindrical member having a hollow portion 1e. The outer cylinder 2 is formed in a conical cylinder having a C-shaped cross section having a conical inner peripheral surface 2a having a downwardly expanding shape and a fitting inner peripheral surface 2b inside the upper end. The outer cylinder 2 is arranged closer to the upper side than the upper side (conical outer peripheral surface 1a side) with respect to the main shaft 1 (closer to the smaller diameter side with respect to the main shaft 1 in the direction along the axis P). .

  The elastic portion 3 is composed of inner and outer three rubber layers (an example of an elastic layer) 4A, 4B and 4C centered on the longitudinal axis P, and inner and outer hard partition walls 5A and 5B. It is equipped over the main shaft 1 and the outer cylinder 2 in a state of being interposed between 1a and the conical inner peripheral surface 2a. Each hard partition 5 is formed from a metal plate such as a steel plate, reinforced plastic, or the like. Each rubber layer 4 and each hard partition wall 5 are each formed in a tapered cylindrical shape in which the cross-sectional view shape in the direction along the longitudinal axis P is a C shape.

  In other words, the shaft spring portion a has a letter C in which the cross-sectional shapes in the direction along the longitudinal axis P of each of the outer peripheral surface 1a, the elastic portion 3, and the outer cylinder inner peripheral surface 2a of the main shaft 1 are aligned in the same direction. In the direction along the longitudinal axis P, the elastic portion 3 is arranged closer to the smaller diameter side with respect to the main shaft 1 and the outer cylinder 2 is elastic in the direction along the longitudinal axis P. The conical laminated rubber structure is arranged close to the small diameter side of the portion 3.

  The damper mechanism b communicates with a damper chamber 9 capable of expansion and contraction (abbreviation of “expansion and contraction”) by relative movement between the main shaft 1 and the outer cylinder 2 in the direction of the longitudinal axis P. An orifice 12 and an orifice tube 13 following the orifice 12 are configured. The damper chamber 9 is configured by a closing portion 6 that closes an upper end that is one end in the direction of the longitudinal axis P of the outer cylinder 2, a space portion 7 that is surrounded by the main shaft 1 and the elastic portion 3. The upper end of the main shaft 1 is equipped with a plug 10 that covers and closes the hollow portion 1e. The plug 10 is also a component of the space portion 7, and the plug 10 is placed in the direction of the vertical axis P. A small-diameter hole 10a that penetrates is formed to be an orifice 12 that allows the hollow portion 1e of the main shaft 1 and the damper chamber 9 to communicate with each other. The closing portion 6 is configured by a disc lid that is fitted into the upper end of the outer cylinder 2 via the O-ring 11.

  In the hollow portion 1e of the main shaft 1, a spiral orifice tube 13 that is also referred to as a second orifice continuing to the orifice 12 of the stopper 10 is provided. For example, the orifice tube 13 has a small-diameter inner diameter equivalent to that of the orifice 12 and is formed in advance in a spiral shape, and is provided with a tube (metal pipe, non-ferrous metal pipe, synthetic resin pipe, etc.). The tip opening 13a of the orifice tube 13 is opened in the hollow portion 1e that communicates with the outside through the lower end opening 1c. As a result, the damper mechanism b is an air that opens the tip of the orifice 12 to the atmosphere. It is configured as a damper mechanism.

  That is, the space 7 that forms the damper chamber 9 is filled with air (atmosphere, air), and the outer cylinder 2 moves up and down with respect to the main shaft 1 due to load fluctuations, running vibrations, and the like of a railway vehicle (not shown). When the damper chamber 9 expands and contracts due to the air flow, the flow of air between the space 7 and the outside is caused by the flow resistance of the air due to the small diameter and long orifice 12 and the orifice tube 13. Thus, a damper function that attenuates the relative vertical fluctuation between the main shaft 1 and the outer cylinder 2 is exhibited. Although a large damping force is generated by the attachment of the orifice tube 13, when a small damping force is sufficient, the damper mechanism b having only the orifice 12 of the stopper 10 may be used without the orifice tube 13.

  The vehicle shaft spring A according to the first embodiment has the following characteristics. When the main shaft 1 and the outer cylinder 2 move up and down relative to each other, air passes through the orifices 12 and 13 so that high damping performance can be obtained. By providing an orifice tube 13 which is an air column resonance tube following the orifice 12 of the stopper 10, it is possible to reduce vibrations for a specific frequency. That is, by adjusting the natural frequency of the orifice tube 13 (the air resonance tube) to the frequency in question, the energy at the specific frequency can be absorbed by the orifice tube 13.

  Further, when a tick hole is provided in the rubber layer 4 of the elastic part 3, as shown in FIGS. 4 and 5, a blocking film 22 such as a rubber film sufficient to close the tick hole 21 is provided. To do. These blocking films 22 and 22 can be provided in the hole 21 in the manufacturing process of the shaft spring. FIG. 4 shows an example of the minimum area blocking film 22 formed in the outer hole 21 of the outer rubber layer 4C, and FIG. 5 shows an inclined elliptic blocking film 22 formed in the outer hole 21 of the outer rubber layer 4C. It is sectional drawing of the principal part which shows an example. It should be noted that the tying-up structure of the tick hole and the obstruction membrane that compensates for the adverse effects thereof can be similarly applied to Reference Examples 1 and 2 described later.

[Reference Example 1]
As shown in FIG. 2, the vehicle shaft spring A according to the reference embodiment 1 is the same as the vehicle shaft spring A according to the embodiment 1 except that the orifice 12 is different. The different orifices 12 are configured to have through-holes 14 formed in the elastic layer 3, specifically in the intermediate rubber layer 4B, in a state of penetrating in the axial direction. In this case, the hole 10a (see FIG. 1) of the stopper 10 is omitted. In addition, as shown by the phantom line in FIG. 2, there may be a means for providing the orifice 12 by providing an orifice tube 15 having a small-diameter internal passage and vertically passing through the inner rubber layer 4A. This is advantageous in that the length (attenuation) of the orifice 12 can be variably adjusted by adjusting the length.

[Reference Example 2]
As shown in FIG. 3, the vehicle shaft spring A according to the reference embodiment 2 is the same as the vehicle shaft spring A according to the embodiment 1 except that the damper mechanism b is different. The different damper mechanism b is formed by a space 18 surrounded by a face plate 16 fixed to the upper end of the outer cylinder 2, the main shaft 1, and an elastic film 17 stretched between the face plate 16 and the main shaft 1. The damper chamber 9 is configured. The face plate 16 having a circular shape when viewed in the vertical direction is fitted into the fitting inner peripheral surface 2b inside the upper end of the outer cylinder 2, and the fitting inner peripheral surface is first fixed in a state where the lower limit position is fixed by the stepped portion 2c. The O-ring 11 is stacked on the upper side of the annular mounting seat 19 fitted inside 2b.

  The elastic film 17 is formed in a trumpet shape (cone-shaped diaphragm in a speaker) that is circular when viewed in the vertical direction, and is formed using an elastic material such as rubber containing reinforcing fibers. The upper end portion of the elastic film 17 is hermetically fitted to the mounting seat 19 by an upper end peripheral wall 17a fitted inside the inner circumferential surface 19a of the mounting seat 19 and an upper end flange portion 17b along the lower surface 19b of the mounting seat 19. The lower end portion of the elastic film 17 is tightly joined to the upper end wall of the plug 10 provided at the upper end of the main shaft 1. As a result, a space 18 surrounded by the face plate 6, the elastic film 17 and the stopper 10 (main shaft 1) forms a damper chamber 9.

  As in the case of FIG. 1, the stopper 10 is formed with an orifice 12 by a hole 10a penetrating vertically, and the orifice tube 13 following the orifice 12 is also housed in the hollow portion 1e. Is the same as Further, the elastic portion 3 is specifically formed with an air supply / discharge hole 20 penetrating in the direction of the longitudinal axis P in the outer elastic layer 4C. The air supply / discharge hole 20 may be, for example, a circular hole whose diameter is the radial thickness of the outer elastic layer 4C (FIG. 3), but may be other holes.

  In the vehicular shaft spring A of the reference embodiment 2, when the relative vertical movement of the main shaft 1 and the outer cylinder 2 occurs, the damper chamber 9 due to the elastic film 17 and the like changes in size, and thereby, via the orifices 12 and 13. A damper mechanism b in which a damping force is generated by supplying and discharging air to and from the outside. However, due to air supply / discharge through the air supply / discharge hole 20 provided in the elastic portion 3, the volume of the portion other than the damper chamber 9 in the portion surrounded by the face plate 16, the elastic portion 3, the plug 10, etc. The outer cylinder 2 and the main shaft 1 are configured not to change due to relative vertical movement.

  The vehicle shaft spring A according to the reference embodiment 2 has the following characteristics. When the main shaft 1 and the outer cylinder 2 move up and down relative to each other, air passes through the orifices 12 and 13 so that high damping performance can be obtained. By providing an orifice tube 13 which is an air column resonance tube following the orifice 12 of the stopper 10, it is possible to reduce vibrations for a specific frequency. That is, by adjusting the natural frequency of the orifice tube 13 (in-air resonance tube) to the frequency in question, the orifice tube 13 can absorb energy of a specific frequency.

  The shape of the elastic film 17 may be a shape having a smooth surface shape as shown in FIG. 3, but may be the following. That is, when the rigidity of the membrane material is high, as shown in FIG. 6, a plurality of folded portions 23 on the inside of the diameter are provided so that the lanterns are folded several times to achieve high followability and high efficiency. Air supply / exhaust [air supply / exhaust through the orifice 12 between the damper chamber 9 and the atmosphere (external)] can be realized.

[Another Example]
A tank chamber which is a sealed container following the opening of the tip of the orifices 12 and 13 is provided, and air and various gases (inert gas such as nitrogen gas) or gas and oil (fluid) are provided in the orifice, the tank chamber and the damper chamber. A damper mechanism b in which both of them are inserted is also possible.

DESCRIPTION OF SYMBOLS 1 Main shaft 1e Hollow part 2 Outer cylinder 3 Elastic part 4 Elastic layer 5 Hard partition 6 Blocking part 7 Space part 9 Damper chamber 10 Plug 12 Orifice 14 Hole 16 Face plate 17 Elastic film 18 Space part 20 Air supply / discharge hole A Vehicle shaft Spring P Shaft center a Shaft spring part b Damper mechanism

Claims (1)

Laminated rubber in which a plurality of elastic layers and hard partition walls are alternately laminated in the inner and outer directions concentrically or substantially concentrically with the shaft center between the main shaft and the outer cylinder having the same or substantially the same shaft center. A vehicle shaft spring having an elastic part of the structure interposed therein,
The outer cylinder having a C-shaped cross section is arranged close to the small diameter side of the main shaft in the direction along the axis,
In the direction along the axis, the elastic part is arranged closer to the small diameter side with respect to the main shaft, and in the direction along the axis, the outer cylinder is located on the small diameter side with respect to the elastic part. A shaft spring portion of a cone-laminated rubber structure that is arranged close together and has a cross-sectional shape in the direction along the axis is formed in a C shape;
The main shaft is formed in a cylindrical member that has a hollow portion and penetrates in the axial direction, and a stopper that covers and closes the hollow portion is equipped at a damper chamber side end of the main shaft,
Equipped with a damper mechanism comprising a damper chamber capable of expanding and contracting by relative movement of the main shaft and the outer cylinder in the axial direction, and an orifice communicating with the damper chamber;
The damper chamber is configured by a space portion surrounded by a closing portion that closes one end in the axial direction of the outer cylinder, the main shaft, the plug, and the elastic portion,
A shaft spring for a vehicle, wherein the orifice for communicating the hollow portion and the damper chamber with the stopper is formed .

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