JPH10230849A - Rail brake device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To enable the lessening and lightening of a rail brake device. SOLUTION: In a rail brake device 1, permanent magnets 7 are embedded in magnetic cores 4 of electromagnets 3, attracting force of the electromagnets is increased by superimposing the magnetic flux of the permanent magnets on the magnetic flux when exciting coils 5 are excited for the brake operation, braking force is increased, and the same braking force is obtained in states where the device is lessened and lightened in comparison with a conventional device.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

The present invention relates to a rail brake device for a railway vehicle.

[0002]

2. Description of the Related Art Generally, a so-called adhesive brake device utilizing a frictional force between a rail and wheels is used as a brake device for decelerating a railway vehicle. In this adhesive brake device, the maximum possible braking force is determined by the frictional force. In other words, even if the braking force is applied to the wheel as much as possible, the wheel will only slide on the rail while stopping its rotation, and the maximum braking force on the wheel tread will be the friction force generated there The braking force cannot exceed the frictional force.

[0003] These relationships are based on the braking force F of the wheels themselves.
w, the maximum friction coefficient μmax between the wheel and the rail, and the braking force F on the wheel tread, the braking force F on the vehicle tread is
The following equation (1) is obtained.

F ≦ μmax × Fw (1) Here, the friction coefficient μmax <1. In the case of a normal railway vehicle, μmax = about 0.1 to 0.2. Therefore, if it is desired to obtain a braking force exceeding the value obtained by the expression (1), it is necessary to adopt a braking method other than the adhesive braking device.

In recent years, there has been a strong demand for speeding up of conventional line vehicles, and the maximum speed which was conventionally about 100 to 120 km / h has been increased to about 130 km / h or more and about 160 km / h. There is movement.

However, in the case of a conventional line, it is required by law to stop the vehicle within 600 m even when an emergency brake is applied. On the other hand, when trying to stop within 600 m of this accelerated vehicle, the calculated braking force exceeds the maximum friction coefficient μmax, and the wheels slip on the rail surface, resulting in the required braking force being reduced. If it is not obtained, it will not be possible to satisfy the rule of stopping within 600 m.

In order to solve this problem, a rail brake system has been proposed in which the brake force of a vehicle is directly obtained from a rail as a method for increasing the braking force in parallel with the adhesive brake system. Examples of the rail brake device include a structure shown in FIGS.
The rail brake device 101 is mounted on a bogie frame 103 supported by wheels 102, 102. In operation, the hydraulic device 10 is mounted on the rail 104 below the bogie frame 103.
5, the brake shoe 107 at the lower end of the magnetic pole core 106 is brought into contact with the rail 104, and the exciting coil 108 is energized in this state.
Is magnetized into an electromagnet to generate electromagnetic attraction between the rail 104 and the brake force by a frictional force between the brake shoe 107 and the rail 104. Also,
By alternating the direction of the current flowing through the exciting coil 108 with the adjacent exciting coil, the magnetic field generated on the brake shoe 107 side of the pole iron core 106 is arranged alternately, and the vortex is generated on the rail when the electromagnetic coil passes. When an electric current is generated, the magnetic force generated by the eddy current acts oppositely to the magnetic force of the electromagnetic coil 1 in the vehicle traveling direction, and the repulsive force acts as a vehicle braking force.

Looking at the internal structure of the magnetic circuit portion of such a rail brake device 101, as shown in FIGS. 11 and 12, the brake shoe 1 extends along the surface of the rail 104.
07 and a magnetic pole core 106 are arranged, and an exciting coil 108 is wound around the magnetic pole core 106. A plurality of excitation coils 108 are mounted on a frame 109, and the outer periphery is covered with a protective cover 110.

[0009]

In the case of such a conventional rail suction type rail brake device, the rail brake device 101 is provided between the front and rear wheels 102, 102 of one bogie.
Is arranged, but a caliper brake is provided around each wheel 102 so that the traveling direction (longitudinal direction)
There are severe restrictions on the dimensions of. Since it is necessary to incorporate the entire device within the limited dimensions, the pole pitch between the exciting coils and the winding dimensions of the exciting coils are also limited, so that a large braking force cannot be attached. There was a problem that the power was insufficient and the performance with respect to the deceleration of the vehicle could not be sufficiently satisfied.

[0010] The present invention has been made in view of such conventional problems, and provides a rail brake device capable of improving a braking force without increasing the size for mounting in a limited space. The purpose is to do.

[0011]

According to a first aspect of the present invention, there is provided a rail brake device which attracts a rail to a rail by an electromagnet and obtains a deceleration force of a vehicle by a frictional force between the rail and the electromagnet. And a permanent magnet embedded so that the direction of the magnetic force matches the direction of the magnetic pole of the exciting coil of the electromagnet.

In the rail brake device according to the first aspect of the present invention, by embedding a permanent magnet in the pole core of the electromagnet, the magnetic flux of the permanent magnet is reduced to the magnetic flux when the exciting coil is excited for the braking operation. By superimposing, the attraction force of the electromagnet can be increased, and the braking force in a low speed region can be increased.

According to a second aspect of the present invention, in the rail brake device of the first aspect, the permanent magnet is wrapped with a non-magnetic material and embedded in the magnetic pole core, whereby the permanent magnet is inserted into the magnetic pole core. The assembling work is facilitated, the coercive force of the permanent magnet can be maintained for a long time, and the braking performance can be maintained for a long time.

According to a third aspect of the present invention, in the rail brake device of the first or second aspect, a distance from a side surface parallel to the direction of the magnetic force of the permanent magnet to an outer side surface of the magnetic pole core is set to 3 to 5 mm. Accordingly, the magnetic force can be increased without impairing the impact resistance.

According to a fourth aspect of the present invention, there is provided the rail brake device of the first to third aspects, wherein a glass prepreg sheet impregnated with epoxy resin is interposed on a boundary surface between the permanent magnet and the magnetic pole core. As a result, integration between the permanent magnet and the magnetic pole core is promoted, and the impact resistance can be increased.

According to a fifth aspect of the present invention, there is provided the rail brake device according to any of the first to fourth aspects, further comprising a magnetic flux reversing circuit for supplying an exciting current to the exciting coil of the electromagnet in a direction opposite to the magnetic force direction of the permanent magnet when the brake is released. This reduces the force required to pull up the rail brake device by canceling out the magnetic force of the permanent magnet when the brake is released by the magnetic flux generated in the magnetic pole core by the operation of the magnetic flux reversing circuit,
The load on the hydraulic device for raising and lowering the rail brake device can be reduced.

According to a sixth aspect of the present invention, in the rail brake device of the first to fifth aspects, a frictional resistance is provided in a space between the brake shoe attached to the rail-side end surface of the pole core of the electromagnet and the same adjacent brake chute. The auxiliary brake shoe made of a non-magnetic material having a high frictional force is attached, and thereby the braking force can be increased.

[0018]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Embodiments of the present invention will be described below in detail with reference to the drawings. 1 and 2 show a rail brake device 1 according to a first embodiment of the present invention. The rail brake device 1 is mounted and used at the same position as the conventional rail brake device 101 shown in FIG.

The structure of the rail brake device 1 will be described. A plurality of, here four, electromagnets 3 are mounted on the frame 2 along the rail surface. Each electromagnet 3 is formed by winding an exciting coil 5 around a magnetic pole core 4 fixed to the frame 2. A brake shoe 6 is attached to the lower end surface of each magnetic pole core 4. A permanent magnet 7 is embedded in the magnetic pole core 4 so that its four circumferences are covered with a non-magnetic plate material 8 such as a SUS plate.
The periphery of all the electromagnets 3 is covered with a protective cover 9.

The direction of the magnetic force of each permanent magnet 7 is made to coincide with the direction in which the magnetic flux generated by the exciting coil 5 flows in the magnetic pole core 4 in which the permanent magnet 7 is built.

The operation of the rail brake device 1 having the above configuration will be described. When the brake is not operated, the excitation coil 5 is not energized in the state of FIG. 10 shown as a conventional example.

During the braking operation, the hydraulic device is driven to lower the device 1 until the brake shoe 6 contacts the rail surface, and the exciting coil 5 is energized. As a result, the exciting coil 5 excites and generates a magnetic flux, and the N pole and the S pole alternately appear at the lower end of the magnetic pole core 4 of each electromagnet 3 as shown in FIG. The braking force acts by the frictional force between the rail and the brake chute and the repulsive force of the magnetic field generated by the eddy current generated in the rail, thereby decelerating the vehicle.

During the braking operation, the permanent magnet 7
Since the direction of the magnetic force is matched with the direction of the magnetic flux passing through the magnetic pole core 4 containing the magnetic force, the magnetic flux flowing through the magnetic pole core 4 is larger than the magnetic flux of the exciting coil 5 alone. Therefore, as shown by a curve A in FIG. 3, a larger magnetic attraction force can be generated, especially in a low speed range, as compared with the conventional braking force curve B, and the braking force can be increased by ΔF. . Therefore, a magnetic circuit of the same size as the conventional one can generate a stronger braking force than the conventional one, and if it is desired to obtain the same braking force as the conventional one, a magnetic circuit smaller than the conventional one can be used. , Weight reduction can be achieved.

Next, a second embodiment of the present invention will be described with reference to FIGS. The feature of the second embodiment is that the size of the permanent magnet 7 incorporated in each pole core 4 and the non-magnetic material 8 covering the same is set in a direction orthogonal to the magnetic flux direction Br by 3 to 3 from the side of the pole core 4. The point is that it is set in the range of 5 mm.

As shown in the graph of FIG. 5, for example, the brake force acting on the magnetic pole
Assuming that the impact force is 10 to 20 times, the permanent magnet 7 built in the magnetic pole core 4 is increased to increase the permanent magnet 7 from the outer surface of the magnetic pole core 4 in a direction perpendicular to the magnetic flux direction Br. As the thickness α to the peripheral surface is reduced, the mechanical strength of the magnetic pole core 4, that is, the safety factor f decreases on the quadratic curve. Conversely, if the attraction characteristics H of the permanent magnet 7 are plotted on the safety factor f side, the smaller the thickness α, the larger the size, and the larger the quadratic curve. In order to satisfy both of these contradictory elements and to increase the braking force without impairing the mechanical strength, it is appropriate to set the range of 3 to 5 mm as ± 1 mm of 4 mm thickness at the branch point. That's how it was set.

Next, a third embodiment of the present invention will be described with reference to FIG. The feature of the third embodiment is that the electromagnet 3 according to the first embodiment or the second embodiment is different from the first embodiment.
A non-magnetic material 8 is placed around the permanent magnet 7 built in the magnetic pole core 4 and a glass prepreg sheet 11 is further put around the permanent magnet 7, and inserted into the magnetic pole core 4,
The point is that the magnetic pole iron core 4, the nonmagnetic material 8, and the permanent magnet 7 are fixed and integrated by impregnating and curing an epoxy resin.

By using the glass prepreg sheet 11 in this manner, the magnetic pole core 4, the non-magnetic material 8, and the permanent magnet 7 can be strongly integrated, and the impact force applied to the magnetic pole core 4 during braking operation is increased. It can be moderated and the impact resistance can be improved.

Next, a fourth embodiment of the present invention will be described with reference to FIG.
A description will be given based on FIG. The feature of the fourth embodiment is that, while maintaining the braking force at the time of the braking operation, the magnetic force of the permanent magnet 7 at the time of releasing the brake weakens the force that the magnetic pole core 4 is attracted to the rail surface. The device 1 is a hydraulic device (the hydraulic device 1 in the conventional example of FIG. 10).
(Same as 05), the load applied to the hydraulic device when lifting is reduced as in the conventional case.

FIG. 7 shows a magnetic circuit for exciting each of the exciting coils 5. In order to use the present apparatus 1 as an emergency brake, a battery 21 as a power source, five switches SW1 to SW5, a diode D and switch S
It comprises a control circuit 22 for performing switching control of W1 to SW5.

Switches SW1 to SW by control circuit 22
The on / off switching control of No. 5 is based on the timing chart of FIG. During normal driving, all switches SW1 to SW
Leave 5 off. When a brake operation command is input, the control circuit 22 first switches SW1 to SW
3 is turned on to excite the exciting coil 5 by flowing a current from the battery 21 in a direction in which a magnetic flux φi in the same direction as the magnetic force φpm of the permanent magnet 7 is generated. Thus, the magnetic flux φpm generated by the permanent magnet 7 and the magnetic flux φi generated by the exciting coil 5 are applied to the magnetic pole core 4.
Are superposed, and the magnetic pole core 4 can be attracted to the rail surface with a large magnetic force.

The control circuit 22 monitors the speed signal, and when the vehicle speed decreases sufficiently, for example, 30 to 50
When the speed is reduced to a preset speed X in the range of km / h, the switches SW1 to SW3 are turned off and the switches SW4 and SW5 are turned on. As a result, the direction of the current flowing through the exciting coil 5 is reversed, and a magnetic flux −φi in a direction to cancel the magnetic flux φpm generated by the permanent magnet 7 is generated. As a result, the magnetic force in the magnetic pole core 4 is weakened, and the magnetic attraction to the rail surface is lost.

Therefore, when the vehicle is stopped and the device 1 is pulled up by the hydraulic device to release the brake, the attraction force of the permanent magnet 7 against the rail surface is canceled out, so that the rail can be pulled up lightly. become,
The load on the hydraulic device can be reduced.

After returning the apparatus 1 to the inoperative position, all the switches SW1 to SW5 are turned off.

Next, a fifth embodiment of the present invention will be described with reference to FIG. The feature of the fifth embodiment is that an auxiliary shoe 31 made of a non-magnetic material and having a high abrasion resistance and a large friction resistance is provided between the brake shoes 6 and 6 attached to the lower end surfaces of the magnetic pole cores 4 and 4. It is in the point provided. By providing the auxiliary shoe 31 in this manner, the braking force is increased by the frictional force of the portion of the auxiliary shoe 31 in addition to the frictional force between the brake shoe 6 and the rail surface that are in contact with each other due to the electromagnetic attraction force. And a large braking force can be obtained.

[0035]

As described above, according to the first aspect of the present invention,
Since a permanent magnet is embedded in the magnetic core of the electromagnet,
When exciting the exciting coil for the brake operation, the magnetic flux of the permanent magnet is superimposed on the magnetic flux to increase the attraction force of the electromagnet, thereby increasing the braking force.
The device can be reduced in size and weight.

According to the second aspect of the present invention, the permanent magnet can be easily incorporated into the magnetic pole core, and the coercive force of the permanent magnet can be maintained for a long time, so that the same braking force can be maintained for a long time. Can be maintained across.

According to the third aspect of the present invention, since the distance from the side surface parallel to the direction of the magnetic force of the permanent magnet to the outer surface of the magnetic pole core is set to 3 to 5 mm, impact resistance is impaired. Without increasing the magnetic force, a large braking force can be obtained.

According to the fourth aspect of the present invention, since the glass prepreg sheet impregnated with epoxy resin is interposed at the interface between the permanent magnet and the magnetic pole core, the permanent magnet and the magnetic pole core are integrated to provide impact resistance. Can be increased.

According to the fifth aspect of the present invention, since the magnetic flux reversing circuit for supplying an exciting current in a direction opposite to the magnetic force direction of the permanent magnet to the exciting coil of the electromagnet when the brake is released is provided, the magnetic force by the permanent magnet when the brake is released is reduced. The magnetic flux generated in the magnetic pole core is canceled by the operation of the magnetic flux reversing circuit, the force required for lifting the device is reduced, and the load on the hydraulic device for driving the device up and down can be reduced.

According to the sixth aspect of the present invention, the auxiliary brake shoe made of a non-magnetic material having a high frictional resistance is mounted between the brake shoes mounted on the rail-side end face of the magnetic pole core. The braking force can be increased, and a larger braking force can be obtained.

[Brief description of the drawings]

FIG. 1 is a front sectional view of a first embodiment of the present invention.

FIG. 2 is a side sectional view of the embodiment.

FIG. 3 is a graph showing brake characteristics of the embodiment.

FIG. 4 is a sectional view showing a magnetic pole core and a permanent magnet used in a second embodiment of the present invention.

FIG. 5 is a graph showing a relationship between a permanent magnet size, a safety factor, and a braking force according to the embodiment.

FIG. 6 is a partially cutaway sectional view showing a fixed state of a permanent magnet according to a third embodiment of the present invention.

FIG. 7 is a circuit diagram of a magnetic circuit used in a fourth embodiment of the present invention.

FIG. 8 is a timing chart showing the operation of the embodiment.

FIG. 9 is a partially cutaway front view of a fifth embodiment of the present invention.

FIG. 10 is a front view of a conventional example.

FIG. 11 is an enlarged sectional view of a portion A in FIG. 10;

FIG. 12 is an enlarged sectional view taken along line BB in FIG. 10;

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Rail brake device 2 Frame 3 Electromagnet 4 Magnetic pole core 5 Excitation coil 6 Brake shoe 7 Permanent magnet 8 Non-magnetic material 9 Protective cover 11 Glass prepreg 21 Battery 22 Control circuit 31 Auxiliary shoe

Claims (6)

[Claims] 1. A rail brake device which is attracted to a rail by an electromagnet and obtains a deceleration force of a vehicle by a frictional force between the rail and the electromagnet. A rail brake device comprising a permanent magnet embedded so as to coincide with a magnetic pole direction. 2. The rail brake device according to claim 1, wherein the permanent magnet is wrapped with a non-magnetic material and embedded in the pole iron core. 3. The distance from the side surface parallel to the direction of the magnetic force of the permanent magnet to the outer surface of the magnetic pole core is 3-5.
The rail brake device according to claim 1, wherein the rail brake device is set to mm. 4. The rail brake device according to claim 1, wherein a glass prepreg sheet impregnated with epoxy resin is interposed at a boundary surface between the permanent magnet and the magnetic pole core. 5. The rail brake device according to claim 1, further comprising a magnetic flux reversing circuit for supplying an exciting current to the exciting coil of the electromagnet in a direction opposite to a magnetic force direction of the permanent magnet when the brake is released. . 6. An auxiliary brake shoe made of a non-magnetic material having high frictional resistance is attached to a space between a brake shoe attached to a rail-side end surface of a pole core of the electromagnet and an adjacent brake chute. The rail brake device according to any one of claims 1 to 5.