JPH0236402B2 - TAIYAPAN KUKENCHISOCHI - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION (Field of Industrial Application) The present invention relates to a tire puncture detection device for detecting a tire puncture of a vehicle running on a track using pneumatic tires.

(Prior art) Conventionally, for example, as shown in Japanese Patent Application Laid-open No. 59-202913, the load on a tire is detected by a load detector installed on a track, and the load signal is received and the waveform of a normal tire is detected. A known device is designed to determine whether the waveform is caused by a flat tire or a flat tire. This device does not have a way to identify which axle on the train the flat tire is on.
It is necessary to set the number of vehicles and axles per train in advance. Therefore, if this method is applied to a track where trains with different numbers of vehicles and axles coexist, it will not be possible to identify which axle's tire has gone flat.

(Purpose of the Invention) This invention was made in order to eliminate such conventional drawbacks, and it is a method for accurate axle numbering on lines where trains with different numbers of cars and axles are operated on the track. To provide a tire puncture detection device that can count the number of tires on which axle of which train has a puncture.

(Structure of the Invention) The present invention includes a load detector that detects the load caused by the pneumatic tires on both the left and right sides of the same shaft, a display means that processes a signal from the load detector to display a tire puncture, and The first of each train from
A detection means for detecting the passing time between the axis and the second axis or between the second axis and the third axis, and a next axis for setting the time obtained by multiplying this passing time by a predetermined coefficient as the next axis monitoring time. The apparatus includes a monitoring time setting means, and an all-clear means for canceling the detection process and resetting the device to a standby state for the next train if there is no passing signal for the next axis within the next-axis monitoring time.

In the above configuration, the device is reset by the next axis monitoring time setting means and the all clear means every time a train passes, and enters the waiting state for the next train.
Even when applied to a track where trains with different numbers of vehicles coexist, it is possible to reliably identify which train has a flat tire.

(Example) In Fig. 2, 1 is a left side load detector that detects the load from, for example, the left tire among the pneumatic tires on both the left and right sides of the same shaft, and 2 is a right side load detector that detects the load from the right tire. Detector 1,
Sensor 2 may be any sensor as long as it can extract load signals in time series, and usually a load cell, pressure-sensitive switch, piezoelectric element, etc. is used, and this is installed on the tire rolling surface of the vehicle track. Both detectors 1 and 2 detect when the internal pressure of both tires is normal.
As shown in Figure 3A and B, the tire contact lengths t ₁ and t ₂
And the load peak values p ₁ and p ₂ output substantially similar waveform signals A and B with no significant difference. On the other hand,
In the case of an abnormal (flat) tire, a large change occurs in the detection signal on the abnormal tire side. Third
Figures C, D, and E show cases where the output signal of the right side detector 2 changes due to a puncture of the right side tire. C shows the output signal B ₁ in a state where the internal pressure of the tire is maintained to such an extent that the auxiliary wheel built into the tire or coaxially attached does not yet come into contact with the load detector 2, such as at the time of a puncture. Output signal B ₁ at this time is a normal signal (output signal of left side detector 1)
Compared to A, the tire contact length t ₂ is larger and the load peak value p ₂ is smaller. In addition, in D, the internal pressure decreases further and the auxiliary wheel hits the load detector 2,
As a result, the load peak value is reduced in the middle of the tire passage.
p ₂ is protruding, showing an output signal B ₂ that is approximately equivalent to the normal peak value p ₁ , and E is an output signal in which the load transmission by the auxiliary wheel has further increased and the protrusion amount of the load peak value p ₂ has increased. Showing B ₃ .

The output signals from both detectors 1 and 2 are as follows:
The waveform synthesizer 3 shown in FIG. 2 synthesizes the signals in a subtractive manner. The synthesized waveform by synthesizer 3 is
4. Corresponding to FIG. Figure 3 A, B
In the normal tire range, as shown in Fig. 4A and B, the tire contact lengths t ₁ and t ₂ and the load peak values p ₁ and p ₂ of the left tire side signal A and the right tire side signal B are slightly different from each other. Due to the difference, in the case of the examples shown in FIGS. 3A and 3B, signals C and D are taken out almost only on the negative side.
In contrast, the right tire was punctured in Figure 3 C, D,
In the abnormal region of E, waveform signals E, F, and G spanning both positive and negative sides are extracted as shown in FIG. 4, C, D, and E.

The output signals C to G from the waveform synthesizer 3 are input to the positive and negative level comparators 4 and 5 shown in FIG. +L, -L), and if the composite waveform signal exceeds these reference values +L, -L,
As shown in FIG. 5, a pulse signal corresponding to the exceeded portion (number of times) is output. That is, the fourth
In the case of composite waveform signals C and D in figures A and B, two negative side pulse signals C ₁ , C ₂ and
D ₁ and D ₂ are output. In the case of composite waveform signal E in FIG. 4C, which is a puncture signal, the positive side 1
, two on the negative side, a total of three pulse signals E ₁ , E ₂ , E ₃ ,
In the case of composite waveform signal F in FIG. 4D, positive and negative 2
In the case of a composite waveform signal G of four pulse signals F ₁ to F ₄ and E, a total of five pulse signals G ₁ to _{G 5} , two on the positive side and three on the negative side, are output.

As described above, when a tire is punctured, a total of three or more pulse signals are output from the positive and negative level comparators 4 and 5. This pulse signal is transmitted to the logic section 14.
is sent to counters 6 and 7 through counters 6 and 7.
The total number of pulses counted in step 7 and then passed through the adder circuit 23 and counted by the judge 8 (the number of times the composite waveform exceeds the positive and negative reference values +L and -L) and the preset reference pulse number. (2 pulses), and if the number of pulses exceeds this reference value (3 or more), it is determined that there is an abnormality (punk), and while the reset signal Rs described later is being input, the above abnormal signal is The information is input from the determiner 8 to a display unit 9 equipped with an indicator light and the like. In addition, in the determiner 8,
It is determined that there is an abnormality on the condition that pulses are output from both counters 6 and 7, and when pulses are output from only one [cases A and B in Fig. 5, etc.]
, even if the number of pulses is large, it is not determined to be abnormal.

In addition, output signals A and B from the load detectors 1 and 2 in FIG. 2 are also sent to trigger circuits 11 and 12,
When this signal exceeds a predetermined trigger level _L1 , pulse signals a and b shown in FIGS. 6A and 6B are output. This level (first level) L ₁ is set to a small value within a range that is not affected by zero point errors of the load detectors 1 and 2 in order to improve detection accuracy. This pulse signal (first signal) a, b
is input to the OR circuit 13 in FIG. 2, and a reset signal R is outputted [FIG. 6C], and this reset signal R is input to the logic section 14 together with the output signals of the comparators 4 and 5.

As shown in FIG. 7, the logic section 14 includes an OR circuit 1 which receives the output signals of the comparators 4 and 5 as one input.
5, 16, and a knot circuit 1 that inverts this signal.
7, 18, first AND circuits 19, 20 which input the output signals of the NOT circuits 17, 18 and the OR circuits 15, 16, and the AND circuit 1.
It consists of second AND circuits 21 and 22 which AND the output signals of 9 and 20 and the reset signal. Note that the output signals of the second AND circuits 21 and 22 are also input to the OR circuits 15 and 16. As a basic principle, this logic unit 14 counts the mutual behavior of the composite waveform: (a) Exceeding the positive reference value + L → exceeding the negative reference value - L (B) Exceeding the negative reference value - L → exceeding the positive reference value + L It is something to do. That is, when a signal is generated only from the comparator 4, the signal is sent to the AND circuit 19 through the OR circuit 15, and at this time, since the AND circuit 19 does not have a signal from the comparator 5, The NOR circuit 17 side is turned on and a signal is sent to the first AND circuit 21, and since the reset signal R is also sent here, a signal is sent to the counter 6. Similarly, if a signal is generated only from the comparator 5, the signal is sent to the counter 7.

The output signal of the logic section 14 shown in FIG. 2 is taken into the determiner 8 via the counters 6 and 7 and the adder circuit 23 as described above. The outputs of the counters 6 and 7 and the reset signal R are input to a comparator 24, and it is determined whether the punctured tire is on the right or left side depending on whether the number of positive or negative input pulses is greater.

The signal from the load detector 1 is also sent to a trigger circuit 31, and when this signal exceeds a predetermined trigger level _L2 , the signal is sent to an AND circuit 33. Similarly, the signal from the load detector 2 is also sent to the other side of the AND circuit 33 through the trigger circuit 32. This level (second level)
_L2 is set between the expected minimum value of the load peak values at the time of a puncture shown in FIG. 8 and the maximum load caused by a foreign object. above level
A signal of L ₂ or more (second signal) triggers the trigger circuit 31,
32, the AND circuit 33
A signal P is sent to the reset signal generation circuit 34 from which a reset signal Rs is sent to the comparator 24.
and is sent to the determiner 8, and only during that time the comparator 24
and causes the determiner 8 to process. The reset signal R from the OR circuit 13 is also input to the reset signal generating circuit 34.

The reset signal generating circuit 34 is constructed as shown in FIG. That is, an OR circuit 35 which receives the signal P from the AND circuit 33 shown in FIG. 2 as one input, an AND circuit 36 which receives this signal as one input, an off-delay 37 which receives this signal It has an OR circuit 38 which takes as one input, an AND circuit 39 which takes this signal as one input, and a NOT circuit 40 which takes as input the signal R from the OR circuit 13 shown in FIG. The output of the NOT circuit 40 is input to the other side of the AND circuit 39, the output of the AND circuit 39 is input to the other side of the OR circuit 38, and the output of the AND circuit 36 is input to the other side of the OR circuit 35. configured to be entered. Off-day 3 above
Reference numeral 7 is for maintaining the operation of the logic element for a certain period of time, and the hardware may be configured using a circuit element using a capacitor and a resistor, or an off-delay timer. Note that the holding time td is only necessary for operating the next stage logic element, and is usually several msec to several tens of msec.

Figure 10 shows the operation of the reset signal generation system,
As shown in Figure 10A, L ₁ is detected by the tire.
A reset signal R exceeding the trigger level is generated, and then a signal P with a trigger level of level _L2 is generated as shown in FIG. 10B. As a result of the generation of signals R and P, a signal X is generated from the AND circuit 36 (FIG. 9) as shown in FIG. 10C.
As a result, the off-delay 37 is turned on, and its output side is also immediately turned on, and the signal Y is sent to the OR circuit 38 as shown in FIG. 10D. At this time,
On the other hand side of the AND circuit 39, there is a NOT circuit 4.
Since no signal is sent by 0, no output is generated from the AND circuit 39.

When the tire passes and the reset signal R turns off, the other input side of the AND circuit 39 is turned on by the NOT circuit 40, and at this time, the output Y of one input side is also held for a certain period of time by the off-delay 37. Therefore, after the input X is turned off, the AND circuit 39 is turned on and a reset signal Rs is output as shown in FIG. 8 processes the signals from counters 6 and 7. In this way, even if there is a detection signal of level L ₁ or higher, detection processing is not performed immediately, but only when a detection signal indicating the passing of a tire (a signal exceeding level L ₂ ) occurs, it is processed as a tire passing signal. As a result, malfunctions caused by foreign objects can be reliably prevented.

Furthermore, the present invention can also be applied to tire vehicles that do not have auxiliary wheels. In this case, the third
A tire blowout is determined based on the signals of each C shown in FIGS. Further, the tire detection section may adopt a configuration other than the above.

On the other hand, the next axis monitoring time is set by the devices shown in FIGS. 1A and 1B. That is, in FIG. 1A, the signals from the load detectors 1 and 2 are sent to the puncture detection circuit 100 in FIG.
32, and the signals from trigger circuits 11 and 12 are output as signal R shown in FIG. 10A through OR circuit 13, while the signals from trigger circuits 31 and 32 are sent through AND circuit 33 and output as signal R shown in FIG. 10B. It is output as signal P. This signal R and the signal P that has passed through the OR circuit 61 are input to the AND circuit 62 and output as the signal X shown in FIG.
3 is input.

This timing pulse generation circuit 63 includes an off-delay 64, a not circuit 65 arranged in parallel thereto, and an AND circuit 6 to which these signals are input.
6, and the signal X from the AND circuit 62
is input, the 10th
It is output as signal Y shown in Figure D. When the signal X disappears, the NOT circuit 65 is turned on, and since the signal Y is held for a certain period of time, the AND circuit 66 is turned on for a certain period of time after the input X is turned off, as shown in FIG. 10F. The signal K is output as follows.

The signal K is supplied to the knot circuit 6 shown in FIG. 1B.
7, sent to OR circuit 68 and counter 69;
Timing is stopped and reset by inputting the signal K to the timer 70 through the OR circuit 68, and when the signal K is stopped, the signal M shown in FIG. Timing of the interval Ta (N) is started. Further, by inputting the signal K to the counter 69, the number of axes (number of pulses) is counted. When this counter 69 receives an all-clear signal (reset signal for the entire device) _R0 , which will be described later, it takes priority and clears the timer to 0, and enters a standby state.

Output from the above timer 70 (clocked value) Ta (N)
is sent to comparators 80, 81 and multiplier 74,
The multiplier 74 multiplies the result by a time factor Nt and sends the result to determination elements 75 and 76. On the other hand, the signal (count number) from the counter 69 is sent to the determination elements 75 and 76 through the determination devices 71 and 72, and when the passing axle is the first axis (N=1), the determination element 75 is turned on. The passing axle is the second axis (N=
In case 2), the determination element 76 is turned on.

Note that when making a determination between the first axis and the second axis, it is not necessary to provide the determiner 72 and the determining element 76.

By turning on the determination element 75, the signal from the multiplier 74 is sent to the holder 82, where the time factor is determined at the time Ta(1) between the first axis and the second axis.
A value _TA multiplied by Nt is held, and this value _TA is compared with the timed value Ta(N) from the timer 70 in a comparator 81. Similarly, the time between the second and third axes
A value T _A ′ obtained by multiplying Ta(2) by a time factor Nt is held in a holder 83 and compared with a time value Ta(N) from a timer 70 in a comparator 80 . and the clock value
When Ta(N) becomes larger than the comparison values _TA and _TA ', its output is sent to the off-delay 86 through the AND circuit 84 and the OR circuit 85, and the all-clear signal R ₀ shown in FIG. is output, and this signal R ₀ is sent to the counter 69 and holders 82 and 83 to clear the signals accumulated in each and return to the initial state, that is, the state of waiting for input of the next train (standby).

Note that the signal from the counter 69 is also sent to the determiner 73, and even when the count number reaches the preset total number of axes Nv, the signal is sent from the OR circuit 85 to the off-delay 86, and all Clear signal R ₀ is output.

The off-delay 86 is a delay element that does not affect the tire puncture detection function, as long as it can maintain a time sufficient for the immediately succeeding element to operate, usually several milliseconds or less.

Further, instead of the counter 69, a counter as shown in FIG. 11 may be used. That is, the counter 90 has a number-based output counter 91 and a total axle number setting switch 92.
1, the input K is sequentially output by number to turn on each switch of the total number of axles setting switch 92, and the signal of the first axis is sent to the judge 71, and the signal of the second axis is sent to the judge. 72, and when the set total number of axes is reached, the OR circuit 85 outputs an all-clear signal _R0 through the off-delay 86. In this configuration, the determiner 73 that determines whether the set total number of axles has been reached is unnecessary.

As described above, each time a train finishes passing, the entire system is cleared and returned to a standby state for the next train.

12A and 12B show examples of trains operated on tracks to which the detection device is applied, A shows a train consisting of a two-axle vehicle 102 with one axle of tires 101, and B shows a train consisting of a four-axle vehicle 102. The operation of the train will be explained with reference to the flowcharts of FIGS. 13A and 13B for an example in which these vehicles are operated in a mixed manner. First, in Fig. 13A, a train signal is input, and the number of axles N is set to 0 in step _S1 .
is set, and in step _S2 it is determined whether the signal exceeds level _L1 . If it exceeds level L ₁ , time measurement of t ₁ starts in step S ₃ , and then it is determined in step S ₄ whether or not it exceeds level L _{2. If it has exceeded level L 2} , it is determined that the signal is from the axle, so step S ₅ The number of axles N is set to N+1, that is, the first axle is counted, and in step S ₆ it is determined whether or not the level has decreased below level L _1. If it has not decreased, the process of step S ₆ is repeated to determine whether the level has decreased. If so, it means that the axle has finished passing, so the timing of _t1 is stopped in step _S7 .

If the level has not exceeded _L1 in step _S2 , return to step _S2 and repeat the process, and if it has not exceeded level _L2 in step _S4 , check whether the level has fallen below _L1 in step _S8 . determine,
If it has not decreased, the process returns to step _S4 ; if it has decreased, the signal is not from the axle, so the process is reset in step _S9 and the process returns to step _S2 .

Next, move to the flow shown in Figure 13B and step
In _S10 , the maximum number of axles Nv among the number of axles for one train running on the track is set. For example, the above figure 12A
If the 6-car train shown in is the maximum, then 1
Since there are two axes on both sides, Nv is set to 12.

Further, in step _S11 , a timing factor Nt is set. This timing factor Nt is a factor that determines the waiting time after one axle passes until the next axle passes, and therefore, depending on the installation position of the detection device, for example, the train is decelerated. This is determined by considering conditions such as the location near the station or the location where the vehicle will be accelerated. Normally, Nt is set in the range of 4 to 10.

The above maximum number of axles Nv and timing factor Nt are set, and in step _S12 the number of passing axles N is set to the maximum number of axles Nv.
It is determined whether or not it is smaller than that. If the first axle passes, the number of axles N is 1, so
YES, and in step _S13 , time measurement of Ta(1), that is, measurement of the time between the passing of the first axis and the passing of the second axis [see Fig. 10G], starts, and step _S14 starts. It is determined whether the number of axles N is smaller than 2 or not, and since it is YES, Ta(1) is set to Tta in step _S15 .
It is determined whether or not the value is larger than that. This Tta is set to a large value of about several tens of seconds in order to cope with the case where an axle of one train straddles the detection device and stops or decelerates.

After the first axis passes, the second axis usually comes immediately.
Since Ta(1) is smaller than this Tta, the result is NO at step _S15 , and the process moves to step _S16 , where it is determined whether or not the second axis signal exceeds level _L1.If it does, it is determined at step _S18 . Timing of _t1 (time for the tire to pass over the load detector) is started, and in step _S19 it is determined whether level _L2 has been exceeded.
If level _L2 is exceeded, the signal is not caused by a foreign object but by an axle. Therefore, in step _S20 , the number of axles N is set to N+1, that is, the second axle is counted, and then in step _S21 , the signal is lowered from level _L1 . It is determined whether or not it has dropped. If it has dropped, it means that the second axle has finished passing, so the step
Step S ₂₂ stops the timing of t ₁ , and step S ₂₃ stops Ta.
(N-1), that is, the time measurement between the first axis and the second axis is stopped, and in step _S24 it is determined whether the number of axes is smaller than four. Since it is immediately after passing the second axis, the answer is YES here, and then the step
Move to S ₂₅ and set the monitoring time T _A to the time of Ta(1) above by Nt.
Find by multiplying. That is, the next axis monitoring time TA is set immediately after the passage of the second axis.

In addition, on a track where two types of trains shown in Figure 12 A and B are operated together, in the case of the train shown in Figure 12 B, the time Ta(2) between the second and third axles is It is necessary to set the value multiplied by the factor Nt as the monitoring time _TA , and therefore, in step _S24 , it is determined whether the number N of axles is smaller than four.

Next, return to the beginning of the flow in FIG. 13B, compare with Nv in step _S12 , Ta (N) in step _S13 ,
In other words, the timing starts at Ta(2), and the number of axles Nv is compared with 2 in step _S14 . Here, the number of axles N is 2 and becomes NO, so step S14 is performed.
In _S17 , it is determined whether Ta(2) is smaller than T _A.
Normally it will be YES because the third axis will come in,
The process moves to step _S16 , and processing is performed in the same manner as described above up to step _S24 .

Furthermore, if Ta (N) becomes larger than T _A in step _S17 , it means that the next axis has not passed within the predetermined time, so the process is stopped as the train is not passing.
Also, if level L ₂ is not exceeded at step S ₁₉ ,
The process moves to step _S26 , where it is determined whether or not the level has fallen below level _L1 . If it has fallen, it is not an axle signal, so the process is reset at step _S27 and returns to step _S14 , and if it has not fallen again, step S is carried out. Return to ₁₉ .

Proceeding to step S ₂₄ , when comparing the number of axles N with 4, N = 3, so select YES.
Here, Ta(1) and Ta(2) are each Nt
The larger of the multiplied values is set, and if the latter is larger, it is replaced with the previously set value. The latter becoming larger indicates that the train in Figure 12B is passing, and in this case, the second and third axle
T _A is set based on the time Ta(3) with respect to the axis. After setting T _A , the above process is repeated. In other words, immediately after the second axis passes, the monitoring time of the next axis is
If T _A is set and the train shown in Figure 4 B is included, the next axis will be monitored immediately after the third axis has passed.
T _A is set, and the passage of the next axis is then monitored using that T _A.

When the last axle of the train passes, the next axle will not continue to enter, so the comparison between the inter-axle time Ta (N) at step _S17 and the above monitoring time T _A becomes NO, and the process goes to step _S29 . Move, Ta (N)
After the timing has been stopped, the next train is in standby mode in step _S28 . In addition, the maximum number of axles set at the beginning
If the last axle of the Nv vehicle passes, step
The answer is NO in _S12 , and the process moves to step _S28 , where the train waits for the next train.

In this way, regardless of the number of axles, axle counting is stopped every time a train completes passing in preparation for detecting the next train, so even if trains with different numbers of axles are operated together, It is possible to accurately detect which axle tire on a train has become punctured. In addition, since the monitoring time T _A for the next axle is set in accordance with the axle travel time of the passing train, it can be set to the minimum time.
It is possible to prevent unnecessary waiting time from occurring.

(Effects of the Invention) As explained above, the present invention provides a tire puncture detection device with a next axle monitoring time setting means and an all-clear means, so that the detection device is reset every time a train passes, and the next train is detected. Because the system is placed in a standby state, it is possible to reliably identify which tire of which train has a puncture, even if it is applied to a track where trains with different numbers of cars and axles coexist. It is something.

[Brief explanation of drawings]

Figures 1A and B are block diagrams showing an embodiment of this invention, Figure 2 is a block diagram of its tire puncture detection section, Figure 3 is an output waveform diagram of the load detector, and Figure 4 corresponds to its output. Composite waveform diagram, Figure 5 is correct,
Output waveform diagram from negative level comparator, Figures 6A to C
7 is a diagram of the output waveform of the trigger circuit, FIG. 7 is a circuit configuration diagram of the logic section of FIG. 2, FIG. 8 is an explanatory diagram of high and low trigger levels, and FIG. 9 is a circuit diagram of the reset signal generation circuit of FIG. 2. , Fig. 10 is an output waveform diagram of each part of this device, Fig. 11 is a circuit diagram showing another example of the counter, Fig. 12 A and B are explanatory diagrams showing the types of trains operating on the track, Fig. 13 Figures A and B are flowcharts showing an example of processing a detection signal on software. 1, 2...Load detector, 8...Judgment device, 9...
Display section, 11, 12, 31, 32...Trigger circuit, 24...Comparator, 34...Reset signal generation circuit, _L1 ...First level, _L2 ...Second level,
R, Rs...Reset signal, _R0 ...All clear signal, T _A ...Next axis monitoring time, 100...Puncture detection circuit, 101...Tire, 102, 103
……vehicle.

Claims (1)

[Claims] 1 A load detector that detects the load caused by the pneumatic tires on both the left and right sides of the same shaft, a display means that processes the signal from this load detector and displays a tire puncture, and a first shaft of each train from the load detector. and second
a detection means for detecting the passing time between the two axes or between the second and third axes, and a next axis monitoring time setting means for setting the time obtained by multiplying this passing time by a predetermined coefficient as the next axis monitoring time. and an all-clear means for canceling the detection process and resetting the device to a standby state for the next train if there is no passing signal for the next axle within this next axle monitoring time.