JPS6121861B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a bogie for a vehicle, and particularly to a bogie for a railway vehicle suitable for an urban high-speed railway train.

There are various types of conventional railway vehicle bogies, but recently, air springs that allow large lateral displacement in addition to the original vertical displacement have been used to improve the relationship between the car body and the bogie. A method of direct coupling has been attempted. This is shown in Figures 1 and 2.
As shown in the figure. The wheel set 1 has an axle box 2 containing a bearing, and is engaged with a bogie frame 4 via a primary spring 3. The bogie frame 4 determines the relative position of the wheel axle 1, and has one secondary spring 5 on each side along the vehicle traveling direction, and is directly connected to the vehicle body 6 to transmit the vehicle body load to the wheel axle 1. In addition, the traction force and braking force are generated by elastically connecting the center pin 7 provided on the car body 6 and the hole 8 in the center of the bogie frame. 6, it is slidable in a horizontal plane. When the truck swings, the secondary spring 5 undergoes a combined deformation of lateral displacement and torsional displacement. Recently, each ±120
mm, an air spring that allows about ±8° has been developed. This type of bogie structure is simpler than conventional structures, has excellent running and vibration performance, and is useful for reducing weight and cost.

However, in recent years, trains for urban high-speed railways are required to have high acceleration and deceleration, and there is also a growing demand for lighter vehicles in order to reduce power consumption, save energy, and reduce running costs. However, slippage between the wheels and rails is becoming more likely to occur when the vehicle accelerates and decelerates, and it is especially important in the design of urban high-speed trains to fully utilize the torque generated by the electric motor without causing slippage. is important.

Although the above-mentioned bogie is lightweight, no measures are taken to prevent the axle load from shifting within the bogie, and it is not suitable for use under high acceleration and deceleration conditions. As shown in Figure 2, the amount of axle load movement is as follows: Taking acceleration as an example, if the force acting on the connection point between the bogie and the car body 6 is F, and the height from the rail surface to the connection point is h, then
The moment that causes the axle load movement is Fh, and the axle load movement is ΔW, which is the value divided by the distance l between the axles.
That is, it is expressed as ΔW=Fh/l. That is, -ΔW for the first shaft and +ΔW for the second shaft are the amount of weight movement within the bogie, and slips are likely to occur in the first shaft. In other words, if the maximum coefficient of friction between the rail and the wheel is μ, and the axle load at rest is W, then (W-ΔW)×μ is the maximum tangential force, and (W-ΔW)×μ<F /2, slips occur between the rail and the wheels. Due to the weight reduction of vehicles, W is becoming smaller, and F is also increasing due to the requirement for high acceleration.
It is easy to slip, and if slip occurs, it is necessary to avoid it as much as possible because it not only makes it impossible to obtain the specified acceleration force, but also causes problems such as damage due to excessive rotation of the electric motor and severe wear of the wheels and rails.

For this reason, various methods have been tried to reduce the axle load movement amount ΔW, but all of them are designed to reduce the moment that causes the axle load movement.
Efforts have been made to reduce the height h from the rail surface to the connection point between the car body and bogie, and this has been achieved using a complex link mechanism. For example, FIG. 3 shows a system in which traction force is transmitted through a link 11 called a reverse eight link, and the aim is to achieve the same effect as in the case of h=0, where the traction force transmission point is on the rail surface. Although these have been effective for locomotives, they may not be as effective due to the friction of the link mechanism, and the drawback is that these mechanisms are heavy, and for lightweight trains, the first type without sway pillows is
The carts with the structures shown in Figures and 2 had drawbacks that made them unusable. The present invention has been made in view of the above points, and its object is to provide a lightweight vehicle bogie that can prevent axle load movement with a simple mechanism.

In the present invention, an air spring that allows large lateral displacement is arranged as a secondary spring directly above the primary spring, and the air spring supports the vehicle body load.
The present invention is characterized by a structure in which axle load movement can be prevented by adjusting the height of the air spring.

An embodiment of the present invention will be described below with reference to the drawings. Embodiments of the drawings In FIGS. 4 and 5, a wheel set 1 has an axle box 2 containing a bearing, and a primary spring 3.
It is engaged with the bogie frame 4 via. The bogie frame 4 determines the relative position of the wheel axle 1, has a secondary spring 5 (air spring in this embodiment) directly above the primary spring 3, is directly connected to the vehicle body 6, and transmits the vehicle body load to the wheel axle. In addition, the traction force and braking force are generated by elastically coupling the center pin 7 provided on the car body with the hole 8 in the center of the bogie frame. It can slide freely in the horizontal plane. The bogie frame 4 has a structure in which side beams and cross beams are integrally joined as shown. Each of the air springs 5, which are secondary springs, is provided with a commonly used height adjustment valve 10, which adjusts the amount of air in the air spring 5 to a preset height.

A diagram of the air piping system for each air spring 5 is shown in FIG. On the first wheel set 1a, left and right air springs 5
A differential pressure valve 12 is provided between the two, and communication is established only when the differential pressure between the left and right sides is large. This is intended to avoid load imbalance in the event that the air spring 5 is punctured, and usually acts independently on the left and right sides. At the second wheel axle 1b, left and right air springs 5 are communicated with each other, and a throttle 13 is provided thereto to provide damping against rolling of the vehicle body.

By adopting such an arrangement, the second wheel set 1
b is statically supported at one point, and one bogie is supported at three points to reduce the unbalance of the four wheels as much as possible.

The height adjustment valve 10 is normally used, and has a built-in damper to prevent it from responding to fast vibration phenomena.
Also, there is a delay of about 3 seconds.

When the moment Fh that causes the above-mentioned axle load shift occurs, the bogie frame 4 moves to its dynamic center 0, as shown in FIG.
The air spring 5 of the first wheel axle 1a contracts and the air spring 5 of the second wheel axle 1b expands. At this time, the height adjustment valve 10 attached to the vehicle body side detects the spring deflection, controls the amount of air in the air spring 5 based on this signal, and returns the height of the air spring to its original value. That is, as shown in FIGS. 8a, b, and c, in normal cases, the regulating valve body 16, arm 17, and rod 18 do not operate as shown in a, but when the air spring 5 is compressed, air is released as shown in b. Arrow P from Tame
Air flows like this, arm 17, rod 1
8 is displaced upward and flows into the air spring as shown by arrow Q. Also, if the air spring is extended, arm 1
7. The rod 18 operates in the opposite direction to b as shown in c, and the air from the air spring _Q1 is discharged as shown in R. Therefore, the deflection of the primary spring becomes equal between the first wheel set and the second wheel set, and there is no axle weight shift. This shows that the moment Fh was borne only by the change in the load shared by the air springs of the first wheel axle and the second wheel axle. Such an axle load movement phenomenon is much slower than a vibration phenomenon of a vehicle, and it is therefore possible to use a height adjustment valve having the above-mentioned characteristics.

Next, regarding vibration performance, this example is excellent in longitudinal vibrational motion. Conventionally, secondary springs had almost no effect on pitching, which is rocking around the zero point of the bogie frame, but according to this embodiment,
Because the rigidity of the secondary spring is added to the rigidity of the primary spring, this is unlikely to occur. In conventional bogies, pitting was prevented by placing the connection point between the bogie and the car body close to the axle center line, but as the need for such measures became less important, the height h to the connection point was increased. There is no problem, and the side surface shape of the bogie frame can be made straight and simple as shown in FIG.

Furthermore, regarding vertical vibration, there is no essential difference in vibration characteristics from vehicles with conventional bogies. For example, when the first shaft runs over a step-shaped rail joint with a step difference δ, in a conventional bogie, the secondary spring is located in the center of the two shafts, so it is equivalent to running over 1/2 of the step δ, that is, δ/2. However, in this example, 2
Since the second spring is located directly above the shaft, it is subjected to vibrations similar to those caused by riding on a step δ. However, in this embodiment, the vibration characteristics of the conventional bogie and the car body are the same, and 2
Since the spring constant of the second spring is 1/2 that of the conventional trolley, the excitation force against running over a step is the same.

The horizontal vibration is exactly the same as the vertical vibration, and there is no essential difference from the conventional trolley.

Further, according to this embodiment, the vehicle body load is caused by the secondary spring,
Since the load is transmitted linearly to the primary spring and the wheels, no vertical load is applied to the bogie frame, making it possible to significantly reduce the section modulus of the structural members, resulting in weight reduction. In addition, since the mounting parts on the car body side are supported at four points instead of the conventional two-point support on one bogie, the load on each mounting part on the car body side is halved, making it possible to simplify the car body structure from a strength standpoint.

As another embodiment of the present invention, the air spring of the secondary spring may not be provided with a height adjustment valve. In this case, the amount of axle load movement will not be 0, but since the moment that causes axle load movement is absorbed by the rigid spring in which the primary spring and secondary spring are parallel, the spring deflection will be small and the axle load will shift. can be reduced. If the spring constants of the primary and secondary springs are equal, the deflection will be 1/2 and the amount of axle load movement will be 1/2 of the conventional one. The same effect can be obtained even if the air spring is replaced with a coil spring.

According to the present invention, axle load movement can be prevented by controlling the height of the air spring provided directly above the primary spring, and vehicles equipped with this bogie can operate with high acceleration and deceleration. can. Further, since the vehicle body load is directly transmitted to the wheels through the primary spring and the secondary spring, the section modulus of the bogie frame can be lowered and the weight can be reduced.

As explained above, according to the present invention, the air spring provided directly above the primary spring supports the vehicle body load, and the height of the air spring is adjusted to support the axle load with a simple configuration. Movement can be prevented. Furthermore, the height of the air spring can be adjusted with a very simple structure by simply providing a height adjustment valve.

[Brief explanation of the drawing]

FIG. 1 is a plan view of a conventional vehicle bogie, FIG. 2 is a side view thereof, FIG. 3 is a side view of another conventional vehicle bogie, and FIG. 4 is one of the vehicle bogies of the present invention. FIG. 5 is a plan view showing the embodiment, FIG. 5 is a side view thereof, and FIG. 6 is a diagram showing the piping principle of the air spring in the vehicle bogie of the present invention.
FIG. 7 is a side view showing the displacement state of the bogie frame when an axle load shift occurs in the vehicle bogie of this embodiment;
The figure is an explanatory diagram showing the arm displacement of the air spring height adjustment valve and the air flow. A is the normal state, b is the state where the air spring is compressed and air is being supplied, and c is the state where the air spring is extended and air is being supplied. FIG. 1... wheel axle, 2... axle box, 3... primary spring, 4
...Bogie frame, 5...Secondary spring, 6...Car body, 7...
...Center pin, 8...hole, 10...height adjustment valve.

Claims (1)

[Claims] 1. Two wheel axles with wheels, an axle box attached to both sides of the axle, and a side beam that is supported via the axle box and a primary spring, and supports between both ends of the two axles. and a bogie frame integrally formed with a cross beam, which allows rotation in the horizontal plane of the bogie frame and transmits only longitudinal and lateral forces between the bogie frame and the car body, with one end attached to the lower part of the car body and the other end attached to the bogie frame. It is composed of an engaged center pin, an air spring provided between the bogie frame directly above the axle box and the car body to transmit the car body load to the bogie frame, and a height adjustment valve for adjusting the height of the air spring. Characteristic vehicle trolley.