JP4555200B2 - Air spring stopper - Google Patents

Description

  The present invention relates to an air spring stopper for regulating the upper limit of the amount of compressive displacement of an air spring installed in, for example, a railway vehicle.

  In general, an air spring equipped in a railway vehicle or the like is used as a vibration isolator that absorbs vibrations by expanding and contracting in the vertical direction. Further, the air spring may be used as a vehicle height adjusting device that adjusts the vehicle height by changing the working height by injecting and discharging air into the air chamber. By using an air spring as a vehicle height adjustment device, for example, it is easy to get on and off the platform, the vehicle height lowered by reshaping the tread of worn wheels is restored to the original height, or power is supplied from the pantograph Attempts have been made to change the vehicle height when traveling on the ground and when traveling underground from the side of the vehicle.

  However, many air springs have a structure in which the upper limit of the amount of compressive displacement is restricted by the contact between the upper surface plate and the lower surface plate, so simply by changing the operating height when adjusting the vehicle height, The upper limit of the amount of compressive displacement differs depending on the height of the action, and the function of the air spring as a vibration isolator may be reduced.

  On the other hand, Patent Document 1 provides an air spring stopper capable of switching the protruding height, so that the upper limit of the amount of compression displacement is a predetermined magnitude even when the operating height of the air spring is changed. An air spring is disclosed which can be kept at a constant value.

  FIG. 6 shows an air spring disclosed in Patent Document 1. This air spring is provided with an upper surface plate 102 and a lower surface plate 103 at upper and lower ends of a diaphragm (flexible film body) 101, and an upper stopper member 104 having a flat surface 104a and a raised surface 104b is attached to the upper surface plate 102. The lower stopper member 105 having a flat surface 105 a and a raised surface 105 b is attached to the lower surface plate 103.

The upper stopper member 104 is rotatable about the vertical axis, and when the action height of the air spring is set low, the flat surface 104a and the raised surface 104b are changed to the raised surface 105b and the flat surface 105a of the lower stopper member 105, respectively. The raised surfaces 104b are made to face the raised surfaces 105b of the lower stopper member 105 when they are opposed to each other and the height of the air spring is set high. As a result, the upper limit of the amount of compression displacement is set to the same size regardless of whether the height of action of the air spring is set low or high.
JP-A-9-89029 (paragraph numbers 0009, 0014, 0015, FIG. 1)

  However, the air spring stopper provided in the air spring of Patent Document 1 can only make the flat surfaces of the upper and lower stopper members face the raised surfaces, or make the raised surfaces face each other. Only one of the heights can be selected and cannot be adjusted to an intermediate stopper height.

  In addition, since the stopper member is divided into a flat surface and a raised surface, the area of the contact surface that contacts the stopper receiving surface when the amount of compressive displacement of the air spring reaches the upper limit is easily reduced. There is a possibility that stability and toughness as a spring stopper may be lowered.

  In the present invention, the stopper height can be adjusted steplessly, and the area of the contact surface that contacts the stopper receiving surface when the compression displacement of the air spring reaches the upper limit is set to a sufficient size. An object of the present invention is to provide a stopper for an air spring.

  In order to achieve the above object, the air spring stopper according to the present invention is for restricting the upper limit of the compression displacement amount of the air spring, and is provided at the upper and lower ends of the rubber cylinder and the rubber cylinder. And an injection / discharge means for injecting and exhausting fluid into and from the internal space surrounded by the upper and lower metal fittings, and a rubber cylinder. The height of the stopper is adjusted by adjusting the length of the cylindrical body in the central axis direction.

  According to this configuration, the stopper is provided by injecting a fluid into the internal space and extending the rubber cylinder in the central axis direction, or discharging the fluid from the internal space and contracting the rubber cylinder in the central axis direction. The height can be adjusted steplessly. Furthermore, when the amount of compression displacement of the air spring reaches the upper limit, the entire upper metal fitting or lower metal fitting can be brought into contact with the stopper receiving portion, so the area of the contact surface is set to a sufficient size, Stability and toughness as a stopper for an air spring can be improved.

  Although a liquid such as water can be used as the fluid to be injected into the internal space, the air spring stopper can be reduced in weight by using air as the fluid, and the air spring stopper can reduce the weight of the air spring stopper. Impact absorption performance can be improved. In addition, an upper metal fitting and a lower metal fitting are not limited to metal, but are concepts including those made of resin.

  A reinforcing cord inclined in the bias direction is embedded in the rubber cylinder, and the bias direction is set in two directions intersecting each other. Further, due to the change in the internal pressure of the rubber cylinder, the cord angle with respect to the central axis of the rubber cylinder becomes the set code angle in the free state where the minimum length of the rubber cylinder and the maximum length of the rubber cylinder. Change freely between stable code angles.

  As a result, the rubber cylinder can be expanded and contracted in the central axis direction while changing the internal pressure and changing the cord angle of the reinforcement cord while reinforcing the pressure resistance by reinforcing the rubber cylinder with the reinforcement cord. As the internal pressure increases and the cord angle approaches the stable cord angle, the rubber cylinder increases in volume in the direction of the central axis, but with a reduced diameter in the radial direction. The closer to the set cord angle, the smaller the volume by shrinking in the direction of the central axis, although accompanied by radial expansion.

  Here, the free state of the rubber cylinder is a state in which there is no pressure difference between the inside and outside of the rubber cylinder and the elongation in the central axis direction is zero, and the code angle in this state is called a set code angle. Further, the stable cord angle is a cord angle in a state where the internal pressure is sufficiently increased until the elongation in the central axis direction of the rubber cylinder stops, and as the internal pressure of the rubber cylinder increases from the free state. The cord angle of the reinforcing cord comes closer to the stable cord angle from the set cord angle.

  The setting code angle in the free state of the rubber cylinder is set to be larger as the adjustable amount of the length in the central axis direction of the rubber cylinder is increased within a range of more than 54.5 ° and less than 90 °. It is good.

  In other words, ignoring the expansion of the reinforcing cord and the radial restraint caused by the upper and lower brackets, the stable cord angle is 54.5 °, which is the cord angle at which the volume of the cylindrical rubber cylinder is maximized. Become. If the set cord angle is in the range of more than 54.5 ° and less than 90 °, when the fluid volume in the internal space is compressed in the direction of the central axis, the cord angle increases and departs from 54.5 °. Accordingly, the volume is reduced and the internal pressure is increased, so that it can function as a stopper. If the set code angle is less than 54.5 °, the internal pressure is reduced by compressing the fluid amount in the direction of the central axis while keeping the fluid amount constant, so that it cannot function as a stopper.

  Furthermore, the larger the set cord angle within the above range, the greater the amount of stretch of the rubber cylinder from the set cord angle to the stable cord angle. The adjustable amount of thickness can be increased.

  Of the reinforcing cords inclined in two directions, the reinforcing cords inclined in the same direction may be arranged to provide two reinforcing cord layers. The two reinforcing cord layers can be formed by wrapping two wide plies that have been bias-cut, but the upper and lower brackets are wound around the upper and lower brackets at a fixed inclination angle. By rotating the outer circumference of the metal fitting at a predetermined pitch, the reinforcement cords that are inclined with respect to the central axis passing through the upper metal fitting and the lower metal fitting are arranged in the circumferential direction, and the inclination directions of the reinforcement cords of each layer are set to intersect each other. It is good to do.

  As a result, the bead wire for locking the end of the wide ply and the folding of the end of the wide ply can be eliminated and the air spring stopper can be formed compactly. Can do. Furthermore, the process of manufacturing a wide ply that requires expensive equipment, the process of winding a bead wire, and the process of turning back the end of the ply can be eliminated, and for other types of air springs with different lengths and diameters. Even when a small number of stoppers are manufactured, the loss of the reinforcing cord can be eliminated.

  Further, since there is no weft like the wide ply, the diameter expansion during vulcanization molding is not hindered, and the performance of the rubber cylinder can be stabilized. Since the reinforcing cord is hung around the metal fitting also used as the reinforcing cord layer forming jig, the rubber cylinder can be firmly integrated with the metal fitting. The step of fixing the metal fitting to the end of the rubber cylinder after the completion of the rubber cylinder is omitted, and damage to the rubber cylinder due to deformation when the metal fitting is inserted can be eliminated.

  There may be a single reinforcing cord or a plurality of reinforcing cords hung around the upper metal fitting and the lower metal fitting, and they can be appropriately selected in consideration of the thickness of the reinforcement cord. If the reinforcing cord layer is formed by hanging a single reinforcing cord around the upper metal fitting and the lower metal fitting, it can be easily hung at an accurate inclination angle without disturbing the arrangement of the reinforcing cords. On the other hand, if a reinforcing cord layer is formed by hanging a plurality of reinforcing cords around the upper and lower brackets while maintaining a predetermined cord pitch, the reinforcing cords can be arranged with a small number of turns. The time required for rotation can be shortened.

  Specifically, the reinforcement cord is hung on the upper metal fitting and the lower metal fitting. The reinforcement cord is passed over the upper metal fitting and the lower metal fitting at a predetermined set inclination angle. A reinforcing cord is stretched from the outer peripheral surface of one metal fitting to the outer peripheral surface on the opposite side across the surface. Further, the reinforcing cord is routed from one bracket to the outer peripheral surface of the other bracket at a set inclination angle, and the reinforcing cord is stretched from the spanning portion of the other bracket to the outer peripheral surface on the opposite side by shifting a predetermined cord pitch. As a result, the reinforcement cord is hung around the upper metal fitting and the lower metal fitting. By repeating this wrapping operation, the reinforcing cord circulates around the outer periphery of the metal fitting.

  According to this configuration, the reinforcing cords are stretched around the upper metal fitting and the lower metal fitting once, and the reinforcing cords are arranged between the metal fittings in parallel to each other on the opposite side across the central axis. While shifting, it is shifted by a predetermined code pitch, so that the tilt direction can be changed around the center axis while maintaining the tilt angle of the span with respect to the center axis. The reinforcing cords are arranged in the circumferential direction.

  When viewed from the outer periphery, the pair of reinforcement cords spanned by a single run is inclined to the opposite side at the same angle of inclination with respect to the central axis. At the time when the arrangement goes around, two layers of reinforcing cord layers in which the inclination directions of the reinforcing cords cross each other are formed. Since a pair of reinforcing cords inclined to the opposite side are arranged on the opposite side across the central axis by a single wrapping, the reinforcing cords whose inclination directions intersect with each other are not arranged so as to be woven together, and are reinforced It does not interfere with the pantograph action of the code.

  Moreover, this invention provides the air spring provided with said stopper for air springs. That is, the present invention includes a diaphragm, and upper and lower plates provided at the upper and lower ends of the diaphragm, and has a working height by injecting and discharging air into an air chamber surrounded by the diaphragm, the upper plate, and the lower plate. The air spring is provided with an air spring stopper attached to the lower surface plate thereof so as to face the upper surface plate.

  According to this configuration, since the stopper for the air spring that can adjust the stopper height steplessly is mounted, the operation height can be adjusted steplessly without deteriorating the function of the air spring as a vibration isolator. The height of a vehicle equipped with an air spring can be adjusted steplessly. Furthermore, since the stopper height can be adjusted freely by simply injecting and discharging fluid, it is not necessary to leave the vehicle closed for a long period of time when changing the stopper height, and to remove the air spring from the carriage. It can be adjusted easily and reliably. Thereby, the stopper height can be raised or lowered according to the rail state or the like.

  It is preferable that the air spring stopper has a pressure resistance that can withstand the pressure of the internal space set so that the load supported by the air spring can be supported instead of the air spring. Then, for example, when the air spring bursts, the internal pressure of the air spring stopper can be sufficiently increased, and the vehicle can be supported and traveled by the air spring stopper.

  Set the pressure of the internal space of the air spring stopper to be larger than the internal pressure of the air chamber, and adjust the stopper height by changing the pressure difference between the internal space and the air chamber by injecting and discharging fluid. Can be set to a desired size.

  By setting the internal pressure of the air spring stopper larger than the internal pressure of the air chamber, it is possible to prevent the air spring stopper from being crushed by the internal pressure of the air chamber of the air spring. When the internal pressure of the air spring stopper is equal to the internal pressure of the air chamber, the air spring stopper is free. Therefore, the height of the stopper can be adjusted by changing the pressure difference between the internal space and the air chamber. .

  As described above, according to the present invention, since the stopper height of the air spring stopper can be adjusted steplessly by injecting and discharging the fluid, the air spring provided with the air spring stopper is also a vibration isolator. The height of the action can be adjusted steplessly without impairing the function as. As a result, the vehicle height of the vehicle can also be adjusted steplessly, so that the vehicle height lowered due to the reshaping of worn wheels can be accurately restored, or the stopper height can be subtly adjusted according to the rail condition, etc. It can be raised or lowered.

  In addition, since the stopper for air spring is expanded and contracted as a whole to adjust the stopper height, when the amount of compression displacement of the air spring reaches the upper limit, the upper metal fitting or the lower metal fitting is brought into contact with the stopper receiving surface. It is possible to increase the stability and toughness as a stopper for the air spring by setting the area of the contact surface to a sufficient size.

  Hereinafter, the best mode for carrying out the air spring stopper according to the present invention will be described with reference to the drawings. FIG. 1 is a sectional view of an air spring provided with a stopper for an air spring according to the present invention, in which the left half shows a state where the working height is set to the lowest, and the right half shows a state where the working height is set to the highest. Show. FIG. 2 is a sectional view of the air spring stopper.

  The air spring 1 is interposed between the vehicle body side and the wheel side to absorb the vertical vibration transmitted between the vehicle body and the wheel, and adjusts the vehicle height by changing the working height. A diaphragm 2 made of a cylindrical rubber film, an upper surface plate 3 provided at the upper end of the diaphragm 2 and attached to the vehicle body side, and a lower surface plate 4 provided at the lower end of the diaphragm 2 and attached to the wheel side, An air spring stopper 5 for restricting the upper limit of the compression displacement amount of the air spring 1 to the compression stroke amount (St) is mounted on the central upper surface of the lower surface plate 4.

  The space surrounded by the diaphragm 2, the upper surface plate 3 and the lower surface plate 4 is an air chamber 6 in which air is sealed, and the air spring 1 expands and contracts in the vertical direction while repeatedly compressing and restoring the air in the air chamber 6. As a result, vertical vibration is absorbed. Further, the working height of the air spring 1 is adjusted by injecting and discharging air into the air chamber 6. Here, the working height of the air spring 1 means a distance (H) from the lower surface of the upper surface plate 3 to the upper surface of the lower surface plate 4 in a stationary state.

  The upper surface plate 3 is a steel disk, for example, and a stopper receiver 7 facing the air spring stopper 5 is mounted in the center hole thereof. The stopper receiver 7 includes a stopper receiving surface 7 a located on the lower surface side of the upper surface plate 3 and a shaft portion 7 b protruding upward from the stopper receiving surface 7 a, and the shaft portion 7 b penetrates the central hole of the upper surface plate 3. Thus, the stopper receiver 7 is attached to the upper surface plate 3.

  The stopper receiver 7 is formed with a communication hole 8 at the center for communicating the inside and the outside of the air chamber 6, and a connecting portion 9 provided so as to surround the protruding portion of the shaft portion 7 b. A pressurized air supply means (not shown) including a meter is connected. The pressurized air supply means injects or discharges air to the air chamber 6 through the communication hole 8 at a desired pressure.

  The lower surface plate 4 is, for example, a steel disk, and an air spring stopper 5 is placed in a concave portion 4a formed on the upper surface of the center. A laminated rubber 10 formed by laminating a plurality of steel plates 10a and rubber plates 10b is integrally provided on the lower surface side of the lower surface plate 4, and the laminated rubber 10 absorbs vibration in the horizontal direction. ing. A central hole 10 c is formed at the center of the laminated rubber 10, and the central hole 10 c communicates with the outside by a passage 11 attached to the end plate 10 d at the lower end of the laminated rubber 10.

  The air spring stopper 5 includes a cylindrical rubber cylinder 12, and upper and lower metal fittings 13 and 14 provided at the upper and lower ends of the rubber cylinder 12, the rubber cylinder 12, and the upper metal fitting, for example. 13 and a nozzle 16 made of a thin tube as an injection / discharge means for injecting and discharging air into an internal space 15 surrounded by the lower metal fitting 14, and the nozzle 16 penetrates the lower metal fitting 14 and the lower surface plate 4 of the air spring 1. The internal space 15 communicates with the central hole 10c of the laminated rubber 10.

  By injecting and discharging air into the internal space 15 from the pressurized air supply means (not shown) via the passage 11, the central hole 10c and the nozzle 16, the rubber cylinder 12 is expanded and contracted in the direction of the central axis. The stopper height (h) of the air spring stopper 5 is adjusted. The pressurized air supply means includes piping, valves, a compressor, and a pressure gauge, and injects and discharges air into the internal space 15 at a desired pressure.

  By adjusting the stopper height (h) and setting the distance between the upper fitting 13 and the stopper receiving surface 7a of the stopper receiver 7 to a desired compression stroke amount (St), the upper limit of the compression displacement amount of the air spring 1 can be reduced. It is regulated by the compression stroke amount (St). Note that other gas or liquid such as water can be injected into the internal space 15 of the air spring stopper 5 instead of air.

  The rubber cylinder 12 is formed by embedding a reinforcing cord 17 inclined in the bias direction in a cylindrical rubber film, and the bias direction is set in two directions intersecting each other (see FIG. 4). The cord angle of the reinforcing cord 17 with respect to the central axis of the rubber cylinder 12 is set in a range exceeding 54.5 ° and less than 90 °.

  The reinforcement cord 17 is made of, for example, a steel cord, and is arranged so as to be hung on the notches 13a and 14a on the end surface side periphery of the upper metal fitting 13 and the lower metal fitting 14, and the reinforcement cords 17 are continuous at the notches 13a and 14a. Thereby, the upper metal fitting 13 and the lower metal fitting 14 and the rubber cylinder 12 are firmly integrated. The material and the number density of the reinforcing cord 17 are set so as to give the rubber cylinder 12 the pressure resistance necessary to support the load supported by the air spring 1 with the air spring stopper 5 instead of the air spring 1. Is done.

  Next, the procedure for changing the working height of the air spring will be described. First, as shown in the left half of FIG. 1, when the working height of the air spring 1 is set to the lowest, the air spring 1 is moved by injecting and discharging air from the pressurized air supply means to the air chamber 6. Adjust to (Hmin). Further, by injecting or discharging air from the pressurized air supply means to the internal space 15 of the air spring stopper 5 through the nozzle 16, the internal pressure thereof is made substantially equal to the internal pressure of the air chamber 6 of the air spring 1, The height of the air spring stopper 5 is set to the stopper height (hmin), and the distance between the upper metal fitting 13 and the stopper receiving surface 7a is made equal to a predetermined compression stroke amount (St).

  When the working height of the air spring 1 is set higher than Hmin, air is injected into the air chamber 6 to adjust the air spring 1 to a desired working height (H). Furthermore, by making the internal pressure of the internal space 15 of the air spring stopper 5 larger than the internal pressure of the air chamber 6 of the air spring 1 and adjusting the pressure difference, the height of the air spring stopper 5 is set to the height of the stopper. Set to (h). The stopper height (h) is a height that makes the distance between the upper metal fitting 13 and the stopper receiving surface 7a equal to a predetermined compression stroke amount (St), and the amount of change in the stopper height (Δh = h−hmin). Is equal to the change amount (ΔH = H−Hmin) of the working height of the air spring 1 (Δh = ΔH).

  Here, the relationship between the pressure difference and the stopper height (h) may be obtained in advance by experiments or the like. As shown in FIG. 3, the relationship between the two is accurately shown by a curve, but the relationship can also be approximately expressed by a linear expression.

  The right half of FIG. 1 shows a state in which the working height of the air spring 1 is set to the highest, the air spring 1 is set to the working height (Hmax), and the air spring stopper 5 is set to the stopper height (hmax). Is set.

  Here, the relationship between the change in the cord angle of the reinforcing cord when changing the stopper height and the elongation in the central axis direction of the rubber cylinder will be described. 4A and 4B are diagrams showing changes in the cord angle of the reinforcing cord accompanying the change in the stopper height. FIG. 4A shows a state in which the stopper height is set to the lowest, and FIG. 4B shows a state in which the stopper height is set to the highest. Shows the state.

  When the stopper height is minimized (hmin) as shown in FIG. 4A, the internal pressure of the internal space 15 of the air spring stopper 5 is set substantially equal to the internal pressure of the air chamber 6 of the air spring 1. As a result, the pressure difference between the internal space 15 and the air chamber 6 becomes substantially zero, the rubber cylinder 12 becomes free, the cord angle of the reinforcing cord 17 forms a set code angle, and the rubber cylinder 12 Is the minimum length. The setting code angle is set within a range exceeding 54.5 ° and less than 90 ° (for example, 70 °).

  When the stopper height is set higher than hmin, the internal pressure of the internal space 15 of the air spring stopper 5 is made larger than the internal pressure of the air chamber 6 of the air spring 1. As a result, the cord angle of the reinforcing cord 17 becomes smaller than the set cord angle, and the rubber cylinder 12 extends in the central axis direction with a radial reduction.

  When the stopper height is set to the highest (hmax) as shown in FIG. 4B, the pressure difference between the internal space 15 and the air chamber 6 is sufficiently increased. As a result, the cord angle of the reinforcing cord 17 forms a stable cord angle (54.5 °), and the elongation in the central axis direction of the rubber cylinder 12 stops and becomes the maximum length.

  Thus, by changing the pressure difference between the internal space 15 and the air chamber 6, the cord angle of the reinforcing cord 17 is changed between the set cord angle and the stable cord angle, and the central axis of the rubber cylinder 12 is changed. The direction length is adjusted. That is, the desired stopper height (h) is set by changing the cord angle of the reinforcing cord 17 to an arbitrary angle between the set cord angle and the stable cord angle.

  Further, by changing the size of the setting code angle within a range exceeding 54.5 ° and less than 90 °, the adjustable amount of the length in the central axis direction of the rubber cylinder 12 is changed. Specifically, as the setting code angle is set larger, the adjustable amount of the length in the central axis direction of the rubber cylinder 12 becomes larger.

  For example, the length of the rubber cylinder 12 in the central axis direction is 70 mm (the height of the stopper including the thickness 20 mm × 2 of the upper metal 13 and the lower metal 14 is 110 mm) to 120 mm (the thickness of the upper metal 13 and the lower metal 14. In order to change the stopper height including 20 mm × 2 within the range of 160 mm, the set code angle is set to α = 70 ° from the relationship of cos α = 70 mm / (120 mm / cos 54.5 °).

  That is, by setting the set cord angle to 70 °, when the inner pressure of the internal space 15 is sufficiently increased to change the cord angle to the stable cord angle of 54.5 °, the rubber cylinder 12 The length in the central axis direction is extended by 50 mm. In addition to the above relationship, it is more preferable to determine the setting cord angle by accurately obtaining the influence of the radial restraint by the upper metal fitting 13 and the lower metal fitting 14 and the influence of the extension of the reinforcing cord 17 by the internal pressure. .

  Next, a method for manufacturing the air spring stopper will be described. First, a donut-shaped unvulcanized rubber is disposed between the upper metal fitting 13 and the lower metal fitting 14 with the nozzle 16, and the unvulcanized rubber is applied so as to cover the lower surface of the upper metal fitting 13 and the upper surface of the lower metal fitting 14. Deploy.

  Next, as shown in FIG. 5, a single reinforcing cord 17 covered with unvulcanized rubber is wound around the upper bracket 13 and the lower bracket 14 while being inclined by a set cord angle with respect to the central axis direction. Two layers of reinforcing cords 17 whose bias directions cross each other are arranged on the entire outer periphery of the doughnut-shaped unvulcanized rubber.

  Here, a procedure for winding the reinforcing cord 17 will be specifically described. First, one reinforcing cord 17 is inclined by a set cord angle (for example, 70 ° when viewed from the outer peripheral side), and is spanned from the peripheral edge of the upper metal fitting 13 to the peripheral edge of the lower metal fitting 14. The reinforcement cord 17 is folded back so as to pass the lower surface side of the lower metal fitting 14 symmetrically with respect to the plane parallel to the bridge portion and passing through the central axis, and is inclined by a set cord angle (for example, −70 ° when viewed from the outer peripheral side). Then, it extends from the peripheral edge of the lower metal fitting 14 to the peripheral edge of the upper metal fitting 13. Further, the reinforcing cord 17 makes a round between the upper metal fitting 13 and the lower metal fitting 14 by folding back the reinforcing cord 17 so as to pass through the upper surface side of the upper metal fitting 13. Thereby, a bridging portion of the reinforcing cord 17 whose bias directions intersect with each other is formed at a position symmetrical with respect to the central axis.

  The reinforcing cord 17 is wound between the upper metal fitting 13 and the lower metal fitting 14 so as to be shifted by the cord pitch when it is made to make one round, and this winding is repeated until the bridging portion from the upper metal fitting 13 to the lower metal fitting 14 reaches the entire circumference. Thereby, the two layers of reinforcing cords 17 whose bias directions cross each other are arranged. Since the two layers of reinforcing cords 17 are arranged without crossing inside and outside, the pantograph action is not hindered.

  Thereafter, an unvulcanized rubber sheet is wound around the outer side of the reinforcing cord 17 and an outer mold is disposed on the outer side, and air is injected from the nozzle 16 into the inner space 15 and heated while being pressurized to be vulcanized and molded. The air spring stopper 5 is completed.

  According to the above configuration, the height of the stopper of the air spring stopper 5 can be adjusted steplessly by injecting and discharging air into the internal space 15, so that the compression of the air spring 1 can be performed regardless of the operating height. The stroke amount (St) can be kept constant. Since air can be supplied to the air chamber 6 of the air spring 1 and the internal space 15 of the air spring stopper 5 by simple piping, valves, and a compressor, the height of the operation can be achieved without removing the air spring 1 from the vehicle. And the stopper height can be adjusted.

  Since the internal pressure thrust of the internal space 15 can be set to a sufficient magnitude by the sufficient pressure resistance of the rubber cylinder 12, the upper metal fitting 13 and the lower metal fitting 14 are set to have sufficient strength and contact area. The load that can be supported by the air spring stopper 5 can be set large. Furthermore, the impact when acting as a stopper can be sufficiently mitigated by the cushioning effect of the air enclosed in the internal space 15.

  The air spring stopper 5 further increases the internal pressure by injecting air into the internal space 15 after the internal pressure of the internal space 15 is sufficiently increased and the cord angle of the reinforcing cord 17 reaches the stable cord angle. Thus, the load supported by the air spring 1 can be supported instead of the air spring 1.

In order to support the load (W) instead of the air spring 1, an internal pressure (p) that generates an internal pressure thrust enough to support the load (W) is required. For example, when the internal pressure (p1) of the air spring 1 is 0.6 MPa and the effective diameter is φ450 mm, the load (W) to be supported is
From W = p1 · a1 (a1: effective area of the air spring),
W = π × (45 cm / 2) × (45 cm / 2) × 0.6 MPa.
When the effective diameter of the rubber cylinder 12 is 200 mm, the required internal pressure (p) is
From W = p · a (a: effective cross-sectional area of rubber cylinder),
W = π × (45 cm / 2) × (45 cm / 2) × 0.6 MPa = p × π × (20 cm / 2) × (20 cm / 2),
The required internal pressure is p = 3 MPa.

  When the breaking pressure of the rubber cylinder 12 is set to be twice or more the internal pressure of 3 MPa, the following three types of cords can be used as the reinforcing cord 17. That is: 1. Six layers of polyester cords (breaking strength per unit width: 2.2 kN / cm) arranged (breaking pressure: 6 MPa). 2. Four layers of aramid cords (breaking strength per unit width: 4.3 kN / cm) arranged (breaking pressure: 8 MPa). Two layers of steel cords (breaking strength per unit width: 9.2 kN / cm) are arranged (breaking pressure: 8 MPa). The setting code angles are all 70 °.

  The air spring stopper 5 is not a member that is constantly subjected to repeated loads and repeated deformations, and the reinforcing cord 17 itself does not necessarily require high fatigue. Further, in actual use, the internal pressure acts on the air chamber 6 to reduce the internal pressure difference acting on the internal space 15 and the tension generated in the reinforcing cord 17. Therefore, the polyester cord, aramid cord, steel cord There is no problem using either one. It is more preferable to adopt a steel cord or an aramid cord that can reduce the number of layers in consideration of traveling in a state where the air spring 1 is burst.

  In addition, since the reinforcing cord layer is formed by winding a single reinforcing cord 17 so as to span the upper metal fitting 13 and the lower metal fitting 14, a bead for locking the reinforcing cord 17 is not necessary, and the rubber cylinder 12 is provided. And the upper metal fitting 13 and the lower metal fitting 14 can be firmly integrated. Furthermore, since the rubber cylinder 12 and the upper metal fitting 13 and the lower metal fitting 14 are integrated when the vulcanization molding is completed, the upper metal fitting 13 and the lower metal fitting 14 are attached to the rubber cylinder 12 after the vulcanization molding. A process can be made unnecessary.

  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 wrapping a single reinforcing cord 17 between the upper metal fitting 13 and the lower metal fitting 14, a ply formed by previously wrapping a plurality of reinforcing cords 17 arranged in parallel with a thin rubber sheet is formed. In addition, a plurality of plies may be stacked. In this case, a rubber cylinder is formed separately from the upper metal fitting and the lower metal fitting, and a bead for locking the ply end is embedded at both ends, and the upper metal fitting and the lower metal fitting are attached to the rubber cylinder. It should be attached.

Sectional drawing of the air spring provided with the stopper for air springs which concerns on this invention Cross section of air spring stopper Diagram showing the relationship between pressure difference and stopper height It is a figure which shows the change of the cord angle of the reinforcement cord accompanying the change of stopper height, (a) shows the state which set the stopper height to the lowest, (b) shows the state which set the stopper height to the highest. Show The figure which shows a mode that a reinforcement cord is wound around an upper metal fitting and a lower metal fitting Sectional view of an air spring provided with a conventional air spring stopper

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Air spring 2 Diaphragm 3 Top plate 4 Bottom plate 5 Air spring stopper 6 Air chamber 12 Rubber cylinder 13 Upper metal fitting 14 Lower metal fitting 15 Internal space 16 Nozzle 17 Reinforcement cord

Claims (9)

An air spring stopper for regulating the upper limit of the amount of compression displacement of an air spring, a rubber cylinder, upper and lower metal fittings provided at upper and lower ends of the rubber cylinder, and a rubber cylinder Injecting and discharging means for injecting and discharging a fluid into an inner space surrounded by the upper metal fitting and the lower metal fitting to change the internal pressure of the rubber cylinder ,
The rubber cylinder is embedded with a reinforcing cord inclined in the bias direction, the bias direction is set in two directions intersecting each other, and the central axis of the rubber cylinder is changed by a change in internal pressure of the rubber cylinder. The cord angle with respect to is freely changeable between a set cord angle in a free state where the minimum length of the rubber cylinder and a stable cord angle which is the maximum length of the rubber cylinder,
For the air spring, the length of the rubber cylinder is adjusted in the central axis direction by changing the cord angle by injecting and discharging fluid into and from the internal space. Stopper. The setting code angle in the free state of the rubber cylinder is set to be larger as the adjustable amount of the length in the central axis direction of the rubber cylinder is increased within a range of more than 54.5 ° and less than 90 °. The air spring stopper according to claim 1 , wherein the air spring stopper is provided. Two layers of reinforcement cord layers are provided, and the upper metal fitting and the lower metal fitting are wound around the outer circumference of the upper metal fitting and the lower metal fitting at a predetermined pitch while the reinforcement cord is wound around the outer circumference of the upper metal fitting and the lower metal fitting at a predetermined inclination angle. with reinforcing cords inclined with respect to the central axis through the lower metal member is arranged in the circumferential direction, according to claim 1 or 2, characterized in that it is set so that the inclination direction of each layer reinforcement code cross each other Air spring stopper. 4. The air spring stopper according to claim 3 , wherein the reinforcing cord layer is formed by winding a single reinforcing cord around an upper metal fitting and a lower metal fitting. 4. The air spring stopper according to claim 3 , wherein the reinforcing cord layer is formed by winding a plurality of reinforcing cords around an upper metal fitting and a lower metal fitting while maintaining a predetermined cord pitch. The reinforcing cord is stretched over the upper metal fitting and the lower metal fitting at a predetermined set inclination angle, and extends across the surface from the outer peripheral surface of one metal fitting of the upper metal fitting and the lower metal fitting. Stretched to the outer peripheral surface, and then spanned from the one metal fitting to the outer peripheral surface of the other metal fitting at the set inclination angle, and the outer circumference on the opposite side by shifting a predetermined cord pitch from the spanning portion of the other metal fitting 6. The air spring stopper according to claim 3 , wherein the air spring stopper is stretched up to the surface. A diaphragm, and an upper surface plate and a lower surface plate provided at the upper and lower ends of the diaphragm, the height of operation can be adjusted by injecting and exhausting air to an air chamber surrounded by the diaphragm, the upper surface plate, and the lower surface plate; An air spring, wherein the lower surface plate is mounted with the air spring stopper according to any one of claims 1 to 6 , facing the upper surface plate. 8. The air according to claim 7 , wherein the air spring stopper has a pressure resistance capable of withstanding a pressure in an internal space set so as to be able to support a load supported by the air spring instead of the air spring. Spring. The stopper for the air spring is set so that the pressure in the internal space is larger than the internal pressure in the air chamber, and the stopper height is adjusted by changing the pressure difference between the internal space and the air chamber by injecting and discharging fluid. The air spring according to claim 7 or 8 , wherein the distance from the upper surface plate can be set to a desired size.

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