JPH08178773A - Detection of pressure of foundation brake rigging - Google Patents

Abstract

PURPOSE: To make it possible to compute the pressure of a brake block in running accurately by obtaining the correlation between the pressure of the brake block to a wheel at the stationary time and the running time of a rolling stock and the strain quantity of the constituent member of a foundation brake rigging at the time of running. CONSTITUTION: In place of a brake block, a testing brake block 12 is assembled into a unit brake device A. When a rolling stock is stationary, compressed air is supplied 3b on the brake cylinder of a wheel 10. A load button 11a is pushed to a tread 10a of the wheel 10, and the pressure of the brake block 12 to the wheel 10 is measured 13. The pressure of the brake cylinder, which is measured at the same time, are inputted into an operation processing part 17 together with the strain quantity of a brake block head 7, which is measured with a strain gage 14. Then, the normal brake block is assembled into the device A again, and the brake-cylinder pressure at the running time of the rolling stock and the strain quantity of the brake block head 7 when the brake block is pushed to the wheel 10 are measured 14. The processing part 17 computes the pressure of the brake block to the wheel 10 at the running time based on the correlation of the measured data at the stationary time and the running time for every preset pressure of the compressed air supplied into the brake cylinder.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a pressing force detection method for a basic braking device mounted on a railway vehicle or the like, which calculates a pressing force for pressing a brake shoe against a wheel when the vehicle is running. .

[0002]

2. Description of the Related Art Conventionally, a railway vehicle or the like is equipped with a basic brake device for generating a braking force by receiving compressed air from a brake cylinder and pressing a brake shoe against a wheel tread. This basic brake device is composed of a brake cylinder, a connecting portion with a brake shoe, a lever mechanism, etc., and amplifies the output of the brake cylinder and transmits it to the brake shoe. In addition, recent railway vehicles are equipped with a unit brake device that integrates the basic brake device, the brake cylinder, and the brake shoe from the viewpoint of ease of assembly into the vehicle and maintenance and repair.

By the way, at the stage of designing and manufacturing a vehicle,
The basic brake device described above is one that generates a pressing force suitable for the vehicle based on the required deceleration calculated from the vehicle specifications such as maximum stop distance, maximum operating speed, and the friction coefficient of the friction material used. Selected and installed. Therefore, in each basic brake device, if the pressing force to be output with respect to the brake cylinder pressure is known in advance, it is possible to select the optimum one suitable for the applied vehicle. Conventionally, the method shown in FIG. 5 has been applied as a method for detecting this pressing force. The figure shows a method of detecting the pressing force of the unit brake device.

In order to measure the pressing force with which the above-mentioned unit brake device A presses the brake shoe against the wheel, two compression type load cells 11 are provided on the side of the brake shoe head 7 facing the tread surface 10a of the wheel 10. Attach these two load cells 11 and connect them to the load measuring device 13.
Input port 3b to the brake cylinder (not shown) built in the
Compressed air is supplied via, and the load buttons 11a of the two load cells 11 are pressed against the stationary wheel 10,
The average value of the pressing force applied to the two load cells 11 is displayed on the load measuring device 13.

The load measuring device is the load cell 1
When the sensing column of No. 1 receives a pressing force and the electric resistance of the strain gauge mounted around the sensing column changes and the current flowing changes, this is converted into a digital electric signal, and the sensing is performed. The pressing force received by the column is directly displayed as a number.
Further, as described above, the load cell 11 is pressed against the stationary wheel and the pressing force at the time of the constant value of the vehicle is measured, so that the bending stress is prevented from being applied to the sensing column of the load cell 11. This is to obtain accurate measurement results and to prevent damage to the load cell 11.

[0006]

However, if the pressing force at a constant value of the vehicle is measured using the load cell 11 as described above and the unit brake device is selected based on this measured value, the vehicle various factors will occur when the vehicle is running. It has been confirmed that the braking force becomes excessive with respect to the original and the wheels are frequently damaged due to the sliding of the wheels 10. The reason for this is that in order to operate the unit brake device A when the vehicle is stationary, a force larger than the static friction force of the connecting portion and sliding portion of each member of the basic brake device incorporated therein is required. On the other hand, it is considered that when the vehicle is running, the basic braking device is vibrated, so that the frictional force at the connecting portion and the sliding portion is reduced, and the reduced frictional force becomes an excessive braking force. ing.

Therefore, the pressing force required in the running state of the vehicle is estimated from the measured value of the pressing force, and the unit brake device is selected based on this estimated value. Since the estimated value is derived from experiments and experience by induction, and because it is a value with a margin, there is often a tendency for excessive braking. As a result, in order to obtain the braking force based on the vehicle specifications, it is necessary to adjust the brake cylinder pressure by adjusting the pneumatic equipment, change the design of the brake command pattern of the brake control device, and the like.

An object of the present invention is to provide a pressing force detecting method for a basic brake device which can measure the pressing force with respect to the brake cylinder pressure when the vehicle is running.

[0009]

According to a first aspect of the present invention, there is provided a method for detecting a pressing force of a basic brake device, wherein compressed air is supplied to a brake cylinder to press a brake shoe against a wheel when the vehicle is stationary. The pressure is measured by the pressure measuring means, the pressing force of the brake shoe against the wheel with respect to the brake cylinder pressure is measured by the load measuring means, and the strain amount of the component member of the basic brake device is measured by the strain amount measuring means. When traveling, supply compressed air to the brake cylinder to press the brake shoe against the wheel, measure the brake cylinder pressure at this time with the pressure measuring means, and measure the strain amount of the constituent members of the basic brake device with respect to the brake cylinder pressure. The force applied to the wheels of the brake shoe when the vehicle is stationary and when the vehicle is running and the basic blur when the vehicle is running are measured. Based on the correlation between the amount of distortion components of the key device, it is obtained to calculate the pressing force to the wheel of the brake shoe during running of the vehicle.

According to a second aspect of the present invention, there is provided a method for detecting a pressing force of a basic brake device, wherein the pressing force detecting means is a load cell attached to the side of the brake shoe facing the tread surface of the wheel, and the strain measuring means is The strain gauge is attached to the brake shoe head of the basic brake device or the push rod of the brake cylinder.

[0011]

According to the pressing force detection method of the basic brake device of the first aspect, the brake cylinder pressure during stationary of the vehicle, the pressing force of the brake shoe against the wheel, and the basic brake device when the brake shoe is pressed against the wheel. The amount of strain of the components of
Calculate the pressing force of the brake shoe on the wheel when the vehicle is running, based on the correlation with the brake cylinder pressure when the vehicle is running and the amount of distortion of the components of the basic brake device when the brake shoe is pressed against the wheel Because I am trying to
It is possible to calculate the pressing force applied to the wheels of the brake shoe while the vehicle is running, irrespective of changes in the frictional force of the connecting parts and sliding parts of the components of the basic brake device when the vehicle is stationary and when the vehicle is running. it can.

According to the pressing force detecting method of the prosecution basic brake device of claim 2, since the pressing force detecting means is a load cell attached to the side of the brake shoe facing the tread surface of the wheel, the load cell is received. When the sensing column receives a pressing force, the electrical resistance of the strain gauge mounted around the sensing column changes. Therefore, by converting the change in the current flowing through the strain gauge into a digital electric signal, the pressing force of the brake shoe against the wheel can be measured.

Further, since the strain measuring means is a strain gauge attached to the brake shoe head of the basic brake device or the push rod of the brake cylinder, the push force of the brake cylinder causes strain in the brake shoe head or the push rod of the brake cylinder. Then, the electrical resistance of the strain gauge attached to the brake shoe head or the push rod of the brake cylinder changes.

Further, since the strain gauge does not come into contact with the wheels, it is not damaged by friction with the wheels, and is not affected by the rotational force of the wheels, either when the vehicle is stationary or when the vehicle is running. Also in, accurate measurement is possible.

[0015]

Embodiments of the present invention will be described. The same components as those of the conventional technique are designated by the same reference numerals, and detailed description thereof will be omitted.

As shown in FIG. 1, a method of detecting the pressing force of the unit brake device A to be tested in this embodiment will be described. This unit brake device A includes a case 2 fixed to a carriage cross beam 1 by a bracket (not shown), a brake cylinder 3 arranged above the case 2 and storing a return spring 3a therein, and a push rod 4 of the brake cylinder 3.
A connecting rod 5 which is rotatably connected at its upper end via a pin 5a and whose lower end is rotatably supported on the case 2 by a pin 5b; and a screw hole 6a provided at the lower end of the connecting rod 5. A spherical bearing 6 that is movably engaged, a suspension member 7b that is swingably suspended outside the bracket through a pin 7a, and a brake shoe that is integrally connected to the lower end of the suspension member 7b. Head 7
A brake shoe 8 fixed to a lower portion of the brake shoe head 7 is rotatably connected to the brake shoe head 7 by a pin 9a, and a rear screw portion 9b is screwed into a screw hole 6a of the spherical bearing 6. The gap adjusting screw rod 9 is formed.

As a procedure for detecting the pressing force, first, a pressure measuring means (not shown) including a pressure sensor is attached to the brake cylinder 3. Instead of the brake shoe 8, as shown in FIG. 2, two compression type load cells 11, which are load measuring means, are arranged on the side of the wheel 10 facing the tread surface 10a in the rotation direction of the wheel 10. The opened test shoe 12 is incorporated into the unit brake device A, and the two load cells 11 are connected to the load measuring device 13, respectively.

On the other hand, a strain gauge 14 which is a strain amount measuring means is attached to the central portion of the brake shoe head 7 which is a constituent member of the basic brake device of the unit brake device A, and the strain gauge 14 has temperature compensation and Young's stress. A bridge box 15 having a built-in bridge circuit for rate compensation and the like and an amplifying device 16 having an A / D converter are connected. Furthermore, the pressure sensor and the amplification device 16 are connected to an arithmetic processing unit 17 such as a microcomputer.

Subsequently, when the vehicle is stationary, compressed air is supplied to the brake cylinder 3 of the wheel 10 through the input port 3b, and the load button 1 of the two load cells 11 is supplied.
1a is pressed against the treads 10a of the wheels 10 which are stationary. Thereby, the wheel 1 of the test brake 12 is
The pressing force to 0 is displayed on the load measuring device 13 as an average value of the loads applied to the two load cells 11, and at the same time, the brake cylinder pressure is measured by the pressure sensor provided in the brake cylinder pressure 3.

Further, the test brake 12 is the wheel 1
When the brake shoe head 7 is distorted by being pressed against 0, the electric resistance of the strain gauge 14 changes, so that the change in the current flowing through the strain gauge 14 is changed through the bridge box 15 and the amplifying device 16. It is converted into a digital electric signal and stored in the RAM of the arithmetic processing unit 17 together with the measured data of the brake cylinder pressure and the pressing force of the test brake 12 to the wheel 10.

In this case, the set pressure of the compressed air supplied to the brake cylinder 3 is increased and decreased stepwise, and the brake cylinder pressure and the pressing force of the test brake 12 onto the wheel 10 are set for each set pressure. Also, the strain amount of the brake shoe head 7 is measured.

Next, after removing the test brake shoe 12 and re-installing the brake shoe 8 in the unit brake device A, the vehicle is run and compressed air is supplied to the brake cylinder 3 in the same manner as described above. Supply, measure the brake cylinder pressure at this time, and measure the strain amount of the brake shoe head 7 when the brake shoe 8 is pressed against the wheel 10,
These measurement data are stored in the RAM of the arithmetic processing unit 17. Also in this case, the set pressure of the compressed air supplied to the brake cylinder 3 is gradually increased or decreased so as to be the same value as described above, and the brake cylinder pressure and the strain of the brake shoe head 7 are set for each set pressure. Try to measure the amount.

Finally, the RAM of the arithmetic processing unit 17
Based on the correlation of each measurement data stored in, the pressing force of the brake shoe 8 against the wheel 10 when the vehicle is running,
It is calculated for each set pressure of the compressed air supplied to the brake cylinder 3. Specifically, when the vehicle is stationary, the pressing force of the pressure brake 8 against the wheel 10 and the brake 8
Of the strain amount of the brake shoe head 7 when the brake shoe 8 is pressed against the wheels 10 while the vehicle is running, and the above calculation processing is performed. This is repeated by repeating every set pressure of the compressed air supplied to the brake cylinder 3.

According to this embodiment, the frictional force of the connecting portion and sliding portion of each component of the basic brake device during stationary and running of the vehicle, for example, the peripheral surface of the pin 5a and the connecting rod 5. It is possible to calculate the pressing force of the brake shoe 8 against the wheel 10 when the vehicle is running, regardless of the friction force between the two and the change in the friction force between the peripheral surface of the spherical bearing 6 and the connecting rod 5. Therefore, if the pressing force is detected in advance for each of the basic braking device, the unit braking device, etc., based on the result of the calculation, a desired amount of braking force can be obtained while the vehicle is running. It is possible to set an appropriate basic brake device that matches the original. Therefore, the braking force does not become excessive with respect to the vehicle specifications due to the reduction of the frictional force of the sliding portion of the basic brake device when the vehicle is traveling.

In the above embodiment, the strain gauge 14 is attached to the center portion of the brake shoe head 7. However, the strain gauge 14 is attached to the tip portion P of the clearance adjusting screw rod 9 shown in FIG. The amount of strain of the clearance adjusting screw rod 9 when pressed against the wheel 10 may be measured. Further, the strain gauge 14 may be attached to the tip of the push rod 19 of the direct push type brake cylinder 18 as shown in FIG. 3 and the strain amount of the push rod 19 may be measured. Furthermore, the strain gauge 14 is attached to the tip of the arm portion 20 corresponding to the basic brake device portion of the lever type caliper device B as shown in FIG. 4, and the brake lining plate 2 attached inside the arm portion 20.
The strain amount of the arm portion 20 when the brake disc (1) sandwiches the brake disc (not shown) may be measured.

If the method of the present invention is applied even after the start of operation of the vehicle, for example, a method for detecting the actual braking force feedback signal of a so-called each-axis control braking device for individually controlling the braking force of each axle is provided. It can be used for such purposes.

[0027]

According to the first aspect of the present invention, the control when the vehicle is running is performed regardless of the change in the frictional force of the connecting portion and the sliding portion of each component of the basic brake device when the vehicle is stationary and when the vehicle is running. The pressing force of the wheel on the wheel can be calculated, and the accuracy can be improved as compared with the case where it is estimated from the pressing force at a fixed value.

According to the second aspect of the present invention, the pressing force detecting means is the load cell attached to the side of the brake shoe facing the tread surface of the wheel. Therefore, when the sensing column of the load cell receives the pressing force, The electrical resistance of the strain gauge attached around the sensing column will change. Therefore, when the change in the current flowing through the strain gauge is converted into a digital electric signal, the pressing force of the brake shoe against the wheel can be measured.

Further, since the strain measuring means is a strain gauge attached to the brake shoe head of the basic brake device or the push rod of the brake cylinder, the push force of the brake cylinder causes strain in the brake shoe head or the push rod of the brake cylinder. Then, the electrical resistance of the strain gauge attached to the brake shoe head or the push rod of the brake cylinder changes. Therefore, when the change in the current flowing through the strain gauge is converted into a digital electric signal, the amount of strain applied to the brake shoe head or the push rod of the brake cylinder due to the brake cylinder pressure can be measured.

Since the strain gauge can measure the strain amount of the brake head or the push rod of the brake cylinder without coming into contact with the wheel, it is not damaged by friction with the wheel and is influenced by the rotational force of the wheel. Therefore, accurate measurement is possible both when the vehicle is stationary and when the vehicle is running.

[Brief description of drawings]

FIG. 1 is a side view in which a unit brake device is broken away.

FIG. 2 is a schematic diagram showing a pressing force detection method for a basic brake device (unit brake device) according to an embodiment of the present invention.

FIG. 3 is a schematic view showing another embodiment of the present invention.

FIG. 4 is a schematic view showing still another embodiment of the present invention.

FIG. 5 is a schematic view showing a conventional pressing force detection method.

[Explanation of symbols]

 3 Brake cylinder 4 Push rod 7 Brake head 8 Brake 10 Wheel 11 Load cell 14 Strain gauge

Claims (2)

[Claims] 1. A pressing force detection method for a basic brake device for measuring the pressing force of a brake shoe, which is connected to a push rod of a brake cylinder via a basic braking device, to a wheel, wherein the brake is applied when the vehicle is stationary. Compressed air is supplied to the cylinder to press the brake shoe against the wheel, the brake cylinder pressure at this time is measured by pressure measuring means, and the pressing force of the brake shoe against the wheel with respect to the brake cylinder pressure is measured by the load measuring means. The strain amount of the constituent members of the basic brake device is measured by the strain amount measuring means, and when the vehicle is running, compressed air is supplied to the brake cylinder to press the brake shoe against the wheel. Of the basic brake device is measured with respect to the brake cylinder pressure by measuring the brake cylinder pressure by the pressure measuring means. Strain amount is measured by the strain amount measuring means, the pressing force to the wheel of the brake shoe during stationary and running of these vehicles, and the strain amount of the constituent members of the basic brake device during running of the vehicle. Based on the correlation of
A pressing force detection method for a basic brake device, comprising calculating a pressing force of the brake shoe against the wheel when the vehicle is traveling. 2. The load measuring means is a load cell attached to a side of the brake shoe facing the road surface of the wheel, and the strain measuring means is a brake head of the basic brake device or a push rod of a brake cylinder. The pressing force detection method for a basic brake device according to claim 1, wherein the strain gauge is attached to the base.