JP2001080481A - Wheel skid preventing method and system - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a wheel skid preventing method utilizing no rotational frequency of wheels, and a system implementing the method. SOLUTION: In deceleration of railroad rolling stock, at least either noise caused between wheels and rails or vibration is detected with noise microphones or with acceleration sensors 4. From the noise or vibration detected, band-pass filters 6 extract noise or vibration of a specific frequency band. On the extraction by the band-pass filters 6 of any noise or vibration of the specific frequency band, decision circuits 7 output ON signals, in accordance with signals from the band-pass filters 6, to controllers 3, which in turn lower the braking pressure. This method can detect signs that wheels are about to skid, just before they skid actually to thus prevent a wheel skid more effectively. The braking force of the rolling stock can also be used effectively.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method for measuring the inherent vibration and noise of wheels and axles generated by wheels rolling on rails immediately before the wheels stick or slide, in a railway vehicle. Detects signs of wheel slipping,
The present invention relates to a method for preventing wheel slippage and a device for implementing the method.

[0002]

2. Description of the Related Art A frictional force, that is, an adhesive force is generated between a wheel and a rail due to a braking force acting when a vehicle is decelerated, but the adhesive force is saturated due to a change in a boundary condition between the wheel and the rail or a change in the braking force. There are cases. Further, when a flat scratch is generated on the wheel tread surface due to sticking or sliding of the wheel, it causes new vibration and noise.

On the other hand, a conventional anti-skid method is, for example, as described in Japanese Patent Application Laid-Open No. 61-199401, in which a rotational speed sensor is attached to a wheel axle to detect a change in the rotational speed of a wheel. It is. When the wheel is slid, the braking force is relaxed when the number of revolutions falls below the reference value, thereby recovering the adhesive force acting between the wheel and the rail and preventing the wheel from slid.

[0004]

However, such a conventional method for preventing skidding is a ratio of a resistance (tangential force) to a traveling direction acting between the wheel and the rail and a vertical load (wheel load). Wheel slip caused by saturation of the sticking coefficient at a certain value is detected by the wheel rotation speed or the rate of change that occurs after the sticking force is saturated. And it was not possible to control just before gliding occurred.

[0005] Further, the conventional anti-skid method uses the number of rotations of the wheels as a control criterion, and thus has a problem that it is greatly affected by the condition between the rails and the wheels. Furthermore, since the slippage of the wheel occurs when the slip ratio between the wheel and the rail ((vehicle speed-wheel speed) / vehicle speed) is about 0.2%, the slippage of the wheel is detected from the change in the number of revolutions and the control is performed. To do this, a highly accurate rotation speed detection sensor is required.

SUMMARY OF THE INVENTION The present invention has been made in view of the above-mentioned problems of the conventional anti-skid method, and provides a wheel anti-skid method without using the number of rotations of a wheel and an apparatus for implementing the method. It is intended to provide.

[0007]

In order to achieve the above object, according to the present invention, at the time of deceleration of a railway vehicle, at least one of noise and vibration generated between wheels and rails is detected by a detector, The noise or vibration detected by the detector is extracted by a filter in a specific frequency band, and when the noise or vibration in the specific frequency band is extracted by the filter, the determination circuit is controlled by the control device based on a signal from the filter. To output an ON signal to reduce the brake pressure.

[0008] By doing so, the state immediately before the sliding can be grasped, and the sliding and the decrease in the adhesive force that occurs earlier and the flat scratches that occur on the wheel tread surface can be prevented earlier. It becomes possible to do.

[0009]

BEST MODE FOR CARRYING OUT THE INVENTION The present inventors have conducted various studies and experiments and found that the tangential force acting between the wheel and the rail, that is, the adhesive force is saturated and the adhesive force between the wheel and the rail is reduced. Immediately before sliding, a stick-slip phenomenon (a state in which the sticking state and the sliding state are repeated in a short time) occurs at the boundary surface between the gripped wheel and the rail in a normal running state, and a specific frequency band excited at this time is generated. By detecting the vibration and noise of the wheel and axle caused by the natural vibration of the axle, it was possible to grasp the state immediately before the run.

FIG. 3 shows the relationship between the axle speed (axle rotation speed), the axle torsional stress, and the noise near the wheels when the wheels slide.
It shows the data obtained by the actual vehicle,
As shown in the lower part of FIG. 3, when the axle rotation speed decreases due to the braking action and the vehicle is stuck, as shown in the upper part of FIG. 3, the torsional stress of the axle greatly diverges immediately before the axle rotation speed decreases. You can see that it is. The diverging frequency at this time was equal to about 90 Hz which is the natural frequency of the axle.

Further, as shown in the middle part of FIG. 3, the noise near the wheels also increases prior to the decrease in the axle rotation speed.
00 Hz noise is observed.

[0012] The present invention has been made based on the above-mentioned findings, and the wheel slippage prevention method of the present invention detects at least one of noise and vibration generated between the wheels and the rails when the railway vehicle decelerates. If the detected noise and vibration are in a specific frequency band, the brake pressure is reduced.

The change in noise or vibration generated between the wheel and the rail during braking on the railroad vehicle detected by the wheel slippage prevention method of the present invention is earlier than the axle speed change point A shown in the lower part of FIG. Since the noise is generated at the point B where the specific noise of the wheel noise starts shown in the middle part of FIG. 3 and the point C where the axle torsional stress starts to diverge shown in the upper part of FIG. Therefore, if the brake pressure is reduced at the moment when the state immediately before the run is detected, compared to the conventional method using a rotation speed detection sensor, the slide and the decrease in the adhesive force that occurs with the run earlier, and furthermore, It is possible to prevent the occurrence of flat scratches on the wheel treads.

The vibrations and noises to be detected in the method of the present invention are generated under all boundary conditions between the wheel and the rail, that is, in any of dry, wet (rainfall) and oiling conditions. Is a natural vibration or a natural noise of the wheel set, and it is possible to catch the phenomenon by extracting only a predetermined specific frequency band.

An apparatus for implementing the wheel slippage prevention method of the present invention includes a detector for detecting at least one of noise and vibration generated between the wheel and the rail, and a noise or vibration detected by the detector. A filter that extracts a specific frequency band of the filter, a determination circuit that outputs an ON signal based on a signal from the filter when noise or vibration of the specific frequency band is extracted by the filter, It is necessary to provide a control device that reduces the brake pressure based on the ON signal. This is the wheel slip prevention device of the present invention.

In the wheel slip prevention device of the present invention, for example, a noise microphone is used as a detector for detecting noise generated between the wheel and the rail, and a detector for detecting vibration generated between the wheel and the rail is used, for example. Adopt an acceleration sensor.

Further, in the wheel skid prevention device of the present invention, as a filter for extracting a noise or vibration detected by the detector in a specific frequency band, the natural frequency of the wheel shaft and the frequency band of generated noise are known. For this reason, by employing a band-pass filter adapted to these frequency bands, the influence of noise can be eliminated.

[0018]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Hereinafter, a wheel slip prevention device according to the present invention will be described with reference to the embodiments shown in FIGS. 1 and 2, and the present invention extends to a wheel slip prevention method according to the present invention using the wheel slip prevention device according to the present invention.
FIG. 1 is a schematic configuration diagram showing a first embodiment of the wheel anti-skid device of the present invention, and FIG. 2 is a schematic configuration diagram showing a second embodiment of the wheel anti-skid device of the present invention.

In FIGS. 1 and 2, 1 is a wheel set, 2 is a brake device for applying a braking force to the wheel set 1, and 3 is a control device for controlling the braking force of the brake device 2. It is installed for each trolley before and after.

Reference numeral 4 shown in FIG. 1 denotes a vibration sensor, for example, an acceleration sensor attached to the end of the axle of the axle 1, and detects, for example, torsional vibration generated on the axle when a braking force is applied to the axle 1. Although this torsional vibration varies depending on the shape of the axle, according to the experiments by the present inventors, the torsional frequency of the axle immediately before the sliding was in a frequency band of 90 to 100 Hz.

The acceleration sensor 4 may be attached to both ends of the axle, or may be attached to either one end. Further, by attaching the acceleration sensor 4 to a portion other than the end portion, not only the torsional vibration of the axle but also the bending vibration of the axle, the bending vibration of the wheel, and the torsional vibration of the wheel can be detected. This is because these vibrations are determined by the shape (wheel, axle, assembly) of the wheel set 1, and do not depend on the boundary conditions between the wheel and the rail.

Reference numeral 5 shown in FIG. 2 is a noise microphone mounted near the wheel set 1, and detects noise generated between the wheel and the rail. The noise generated between wheels and rails is
Although it depends on the shape of the wheels and the running conditions, in the experiments of the present inventors, under normal running conditions, 800 to 1500 Hz
Is generated between the wheel and the rail.

On the other hand, immediately before the run, although varying depending on the shape of the wheels, noise in the frequency band of 4500 to 5000 Hz is generated between the wheels and the rails.
This frequency is a natural frequency specific to the wheel shape.

Reference numeral 6 denotes a band for extracting the vibration and noise in the above-mentioned specific frequency band from the torsional vibration of the axle detected by the acceleration sensor 4 and the noise generated between the wheel and the rail detected by the noise microphone 5. A pass filter is provided for each acceleration sensor 4 and noise microphone 5.

Reference numeral 7 denotes a determination circuit which outputs an ON signal to the control device 3 based on the signal extracted by the band pass filter 6 described above. Then, the control device 3 outputs a signal to the brake device 2 to reduce the brake pressure based on the ON signal from the determination circuit 7.

The wheel slip prevention device of the present invention has the above-described configuration. To prevent wheel slippage using such a wheel slip prevention device, the following is performed. That is, at the time of deceleration of the railway vehicle, the acceleration sensor 4 detects the torsional vibration of each axle generated between the wheel and the rail in the wheel skid prevention device having the configuration shown in FIG. Also,
In the wheel skid prevention device having the configuration shown in FIG. 2, noise generated between the wheel and the rail is detected by the noise microphone 5.

The torsional vibration of each axle detected by the acceleration sensor 4 is input to the band-pass filter 6 in the wheel slip prevention device having the configuration shown in FIG. Further, in the wheel slip prevention device having the configuration shown in FIG.
Is input to the band-pass filter 6.

The band-pass filter 6 has a torsional vibration or noise of a specific frequency band, for example, a torsional vibration of an axle having a frequency band of 90 to 100 Hz, and a noise having a frequency band of 4500 to 5000 Hz. Is extracted. When the noise or vibration in the specific frequency band is extracted by the band-pass filter 6, the determination circuit 7 outputs an ON signal to the control device 3 to reduce the brake pressure and recover the adhesive force acting between the wheel and the rail. Let
It prevents the wheels from slipping.

In this embodiment, the braking force is controlled for each bogie, but the braking force may be controlled for each axle. Further, both vibration and noise may be detected.

[0030]

As described above, according to the present invention,
Since the sign of the sliding of the wheel can be detected immediately before the sliding of the wheel, the sliding of the wheel can be prevented more effectively beforehand. Therefore, it is possible to effectively use the braking force of the vehicle, and it is possible to prevent flat scratches generated on the tread surface of the wheels and noise generated from the wheel and rail systems caused by the flat scratches. , And the life of rails can be extended.

[Brief description of the drawings]

FIG. 1 is a schematic configuration diagram showing a first embodiment of a wheel slip prevention device of the present invention.

FIG. 2 is a schematic configuration diagram showing a second embodiment of the device for preventing wheel slippage according to the present invention;

FIG. 3 shows axle speed (axle rotation speed) during wheel running
FIG. 7 is a diagram showing data obtained by an actual vehicle, showing the relationship between the axle torsional stress and the noise near the wheels.

[Explanation of symbols]

 Reference Signs List 1 wheel axle 2 brake device 3 control device 4 acceleration sensor 5 noise microphone 6 band pass filter 7 judgment circuit

 ──────────────────────────────────────────────────続 き Continuing on the front page (72) Inventor Masao Toruoka 3-19-16 Higashi Ueno, Taito-ku, Tokyo Inside the Teito Expressway Transit Corporation (72) Inventor Masato Kozezawa 3-19-16, Higashi-Ueno, Taito-ku, Tokyo Inside Teito Expressway Transit Corporation (72) Inventor Nobuyuki Ikukata 3-19-16 Higashiueno, Taito-ku, Tokyo Inside Teito Expressway Transit Corporation (72) Inventor Takuto Nakai 5-1-1 Shimaya Konohana-ku, Osaka-shi, Osaka No. 109 Sumitomo Metal Industries, Ltd.Kansai Works Steelworks Office (72) Inventor Masuhisa Tanimoto 5-1-1 Shimaya, Konohana-ku, Osaka-shi, Osaka Sumitomo Metal Industries, Ltd.Kansai Works Steelworks Office (72) Inventor Yasushi Riku 5-1-1109 Shimaya, Konohana-ku, Osaka-shi, Sumitomo Metal Industries Co., Ltd.Kansai Works Steelworks business (72) Inventor Yasutaka Oki Konohana-ku, Osaka-shi, Osaka No. 5-109, Shimaya Sumitomo Metal Industries Co., Ltd. Kansai Works Steelworks F-term (reference) 3D046 AA07 BB28 EE01 HH00 HH25 KK06 5H115 PC02 PG01 QE10 QE14 TO30 TW07 TZ01

Claims (2)

[Claims] At least one of noise and vibration generated between a wheel and a rail when a railway vehicle is decelerated is detected. If the detected noise or vibration is in a specific frequency band, the brake pressure is reduced. A method for preventing wheel slippage. 2. The noise generated between the wheel and the rail,
A detector for detecting at least one of the vibrations, a filter for extracting noise or vibration detected by the detector in a specific frequency band, and a noise or vibration in a specific frequency band extracted by the filter. A determination circuit for outputting an ON signal based on a signal from a filter, and a control device for reducing a brake pressure based on the ON signal from the determination circuit.