RU2340496C2 - Method for detection of braked wheel pairs in rolling equipment in motion - Google Patents

Abstract

FIELD: transportation, physics.

SUBSTANCE: method for detection of braked wheel pairs in rolling equipment in motion is based on recording power of IR (infrared) radiation from wheel elements within limits of strobe pulse of wheel pair pass fixation sensor located in one section with IR radiation receiver inclined at an angle of 90 degrees to road axis and comparing the amplitudes of thermal signals from wheel elements of one axle. Thermal signals minimums are determined within strobe pulses, current values of thermal signals amplitudes are measured in section of these minimums. According to results of these amplitudes comparison against preset value alarm system signal is generated to stop train for checking the condition of brake equipment. This provides identification of rims, disks and hubs overheating occurrences during train service braking in consequence of wheel pairs blocking when brake equipment is faulty.

EFFECT: improvement of brakes technical condition control reliability, reduction of causeless train delays due to control facilities indications of heated wheel elements IR radiation during service braking.

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Description

Known methods and devices for detecting inhibited wheel pairs of moving rolling stock, based on the conversion of infrared (IR) - thermal radiation from heated wheel elements into electrical signals, followed by a comparison of these so-called thermal signals with allowable limit (threshold) values.

So, for example, in the device for non-contact detection of overheated axleboxes for the implementation of this method [1] two additional cameras are used with IR radiation receivers oriented to the interface zones of the hubs and wheel disks at an angle of 90 degrees to the axis of the track (Fig. 1). When a pair of wheels moves in the field of view of these cameras, the rim of the wheel, the disk, the wheel hub first fall, then the disk and the rim of the wheel again. With shoe braking, the most common in the rolling stock of the Russian Railways, of course, rims (bandages) and adjoining mating zones of wheel disks have the highest heating temperature - from 300 to 600 ° C, which is significantly higher than the dynamic range of the receiving-amplifying paths of the devices detection of overheated axle boxes (100-150 ° C).

Therefore, the known devices use gating of thermal signals from the wheels of a rolling stock using an axle counting sensor (DLS) with fixing the passage of the center axis of the wheelset, in which infrared radiation from excessively heated wheel rims (bandages) is excluded from the analysis of thermal signals, while only fragments of thermal signals from disks and wheel hubs were passed to threshold devices only during the duration of the gate pulse (FIGS. 2 and 3).

As a reference, it should be noted that when developing the DISK-BT equipment (1998) with two additional floor cameras oriented to the wheel hubs, the authors set the task of creating an alternative (backup) channel for monitoring the axle box heating. In fact, it turned out that the heating of the wheel hubs, even with short-term braking of the rolling stock (Fig. 1), is several times higher than their potential heating with faulty axle bearings (Fig. 4). For this reason, it became possible to detect only heating of the wheel elements associated with braking of the rolling stock from the thermal signals from the disks and wheel hubs of additional floor cameras with infrared detectors.

So, for example, in the known equipment for detecting overheated axleboxes of the DISK-BT (DISK-2BT) type, auxiliary floor cameras with IR radiation receivers oriented to the interface between the hubs and the wheel disks are intended, in fact, only to detect inhibited wheel sets, which is confirmed in addition to the manual for the operation of the equipment [2]. The essence of the method implemented in these devices is to compare the amplitudes of thermal (IR) signals from both wheels of the same axis during the duration of the gate pulse from the wheel passage sensor. A wheelset is considered to be inhibited if the maximum amplitudes of the thermal signals from the disks and hubs of the left and right wheels of one axis exceed a predetermined threshold level. Since the rim (bandages) and wheel disks have the highest heating temperatures for the braked wheelset, the maximum values measured by the device coincide with the boundaries of the strobe pulses (see Figs. 2 and 3), which does not allow to recognize in which case the heating of the wheels is associated with service braking, and in which case - with a malfunction of the brake system and blocking of the pair of wheels due to incomplete release of the brakes after departure from the station or spontaneous operation of the car brakes en route.

In the first case, the alarm is false, and in the second case it is justified, requiring a train to stop to inspect the brake equipment and eliminate the malfunction that has arisen in operation.

A disadvantage of the known methods and devices for detecting braked wheel pairs of a moving train is the decision on a braked wheel pair according to the maximum amplitudes of the thermal signals from the disks and wheel hubs of one wheel pair in the control zone, that is, within the gate pulse limited by the range of the sensor for fixing the passage of the wheel pair in the field of view of the PC radiation receiver. The longer the duration of the movement of the wheelset in the braked state, the higher the temperature of the rims, rims and wheel hubs, respectively, the greater the amplitudes of the thermal signals at the strobe boundaries, which are taken into account. Figure 2 shows the oscillogram of the heat signal from the wheels as a result of service braking: it is seen from the thermogram that only the rims of the wheels and the adjacent disks are warmed up, and the hubs have a relatively low temperature (a heat signal without pronounced amplitude limits with a deep dip in the center gating pulse).

Figure 3 shows a thermogram of a heat signal from a clearly braked wheelset: it is clear that, in addition to heating the rims, the wheels and wheel hubs are also warmed up (a characteristic two-humped type of heat signal - at the edges of the signal tip there are even restrictions on the dynamic range of the receiving-amplifying channel as a result of excessive heating of the rims). If the IR radiation receiver is inaccurately oriented to the control zone of the wheel hub or when sensors are used to fix the passage of the wheels forming a longer strobe pulse, along with the wheel hub, the warmer outer part of the disk enters the strobe, which is known in the known equipment with the formation of an alarm signal at the maximum the value of the heat signal within the strobe-pulse boundaries (Umax 1) leads to false readings of the control system, including the working heating of the wheels during service braking - the measurement result I get inflated in relation to the "cold" hub (Umin 1).

When implementing the known method of comparing the maximum amplitudes of thermal signals from two wheels of the same axis in the strobe, it is impossible to recognize whether increased heating of the disk and wheel hub is associated with a brake failure (incomplete release of brakes when leaving stations, auto-regulator is tightened, air leaks from the supply tubes, etc. .) or with heating of the wheel hubs during official, adjusting and, most often, stopping braking of the train, which leads to a false response of controls and unreasonable stopping of the train.

The essence of the invention lies in the fact that in a method for detecting inhibited wheel pairs of a rail rolling stock during movement, based on recording infrared radiation power from wheel elements within the strobe pulse of a wheel pair passage fixation sensor located in one section with an IR radiation receiver oriented at an angle of 90 degrees to the axis of the path, and comparing the amplitudes of the thermal signals from the wheel elements of at least one axis in order to recognize cases of increased heating of rims, discs and wheel center during service braking of a train from cases of wheel sets blocking in the event of a brake equipment malfunction, the minima of the thermal signals are found within the strobe pulses, the current values of the amplitudes of the thermal signals are measured in the section of these minima, which, by comparing them with a predetermined value, generate an alarm alarm to stop the train to check the condition of the brake equipment.

According to the proposed method for detecting inhibited wheel pairs of moving rolling stock in order to reduce false readings on the working heating of the wheel elements (disks and hubs) of one or more wheel pairs of a car (locomotive) when the train is braking, it is proposed to measure current amplitudes in the cross section of the heat signal transition through minimum (see figures 2 and 3). Moreover, the longer the duration of the movement of the wheelset in the inhibited state, the greater the amplitude of the signal in the cross section of the minimum of the function (compare Umin 2 and Umin 1 in FIGS. 2 and 3), which is a more reliable criterion for assessing the malfunction of the brake equipment of a rolling stock in comparison with by known methods.

Information sources

1. SU 704846 A1, 12/27/1979.

2. Equipment for the automatic detection of overheated axle boxes on the train (DISK-B). Lozinsky S.N., Trestman E.E., Alekseev A.G. Automation, Telemechanics and Communication, No. 2, 1986, p. 18-21.

Claims (1)

A method for detecting inhibited wheel pairs of a rail rolling stock while driving, based on recording IR radiation power from wheel elements within the strobe pulse of a wheel pair passage fixation sensor located in one section with an IR radiation receiver oriented at an angle of 90 ° to the track axis, and comparing the amplitudes of the thermal signals from the wheel elements of at least one axis, characterized in that, in order to recognize cases of increased heating of the rims, discs and wheel hubs during service braking and trains from wheel lock cases in the event of a brake equipment malfunction, find the minima of the thermal signals within the strobe pulses, measure the current values of the amplitudes of the thermal signals in the section of these minima, comparing them with a predetermined value and generate an alarm signal to stop the train to check the condition of the brake equipment.

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