JPS5835314B2 - Vehicle axle number measurement circuit - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a circuit for measuring the number of axles of a vehicle, and particularly to a circuit for measuring the number of axles of a vehicle, and in particular a signal group from a multi-divided vehicle pressure detector and a vehicle body detector that separately detects each vehicle. The present invention relates to a vehicle axle number measuring circuit configured to measure the number of axles of a passing vehicle based on a signal and automatically determine the traveling direction of the vehicle.

In automating toll collection operations on toll roads and the like, it is known that it is effective to use the number of axles of a vehicle as one means of automatically determining the type of vehicle.

As a method for detecting the number of axles, there is a method in which a belt-shaped detector operated by the pressure of a wheel is arranged almost perpendicular to the traveling direction of the road to detect the passage of the wheel.

When strip-shaped detectors are arranged in the width direction of the road, if a vehicle crosses such a detector diagonally, a wheel on one side of a certain axis passes over the detector and then a wheel on the other side crosses the same detector. Furthermore, since it passes again, there is a drawback that even if only one axis passes, it may be incorrectly measured as two axes passing.

In order to eliminate such drawbacks, for example, in order to automatically measure the number of passing axes even when a vehicle passes in a meandering manner, a detector arranged in multiple parts is used, and each divided Add +1 when the wheel passes forward and -1 when the wheel passes backward to the reversible counter corresponding to each detector, compare the counting results of each counter after the vehicle passes, and calculate the maximum value of the vehicle. It is known that the number of passing axes may be used.

However, with this axle counting method, when the wheels of one vehicle move backward on a different detector than when moving forward, and then move forward on the original detector, the counting result is negative for the axle. If the number is a number, it can be easily inferred that the result of subtracting the maximum number of axles with a negative value from the maximum number of axles with a positive value can be used as the number of axles that the vehicle passes. When it passes through the divided part, then moves backward without pressing the divided part, and when it moves forward for the second time, it passes over a different detector than when it retreated, the result is that +1 axis is added from the actual passing axis. There are drawbacks to getting it.

An example of a passing mode that may cause such a drawback is when the vehicle is biased.

This is one of the passing modes that must be fully considered when measuring the number of axles for one vehicle with high precision.

In order to eliminate this drawback, it is possible to measure the number of axes more accurately by adding a joint detector to the split joint of the detector, but adding a new detector will reduce reliability and increase cost. There is a risk that other problems may arise.

In view of the above-mentioned drawbacks, an object of the present invention is to obtain a detection signal and a vehicle separation signal from a multi-divided detector without adding a new detector, and to obtain a detection signal and a vehicle separation signal from a multi-divided detector, and to detect various passages including special passage manners of vehicles. It is an object of the present invention to provide a vehicle axle number measuring circuit that can more accurately measure the number of passing axles and the direction of passing for a vehicle.

In the present invention, a multi-divided detector that detects wheel information from wheel pressure I is installed in two parts in a direction substantially perpendicular to the traveling direction of the road.
In a vehicle axle number measuring circuit that is arranged in rows and measures the number of axles of passing vehicles, the detection output from each division unit of the multi-divided detector is received, and the traveling direction of the wheels is identified. a traveling direction determining circuit; a pulse generating circuit that receives a detection output from a detector for each division unit and generates one pulse at a starting point when the wheel completes passing through the detector; and the traveling direction determining circuit. a forward axis circumference counter that receives a forward determination output from the forward direction determination circuit and one pulse from the pulse generation circuit to change the count by +1; a backward determination output from the traveling direction determination circuit and one pulse from the pulse generation circuit; A backward axis circumference counter that receives pulses and changes the count by +1, and a forward axis maximum value and a reverse axis maximum value that detect the maximum value of each of the count contents of the forward axis circumference counter and the reverse axis circumference counter. The present invention is characterized by comprising a maximum value detection circuit that obtains the value, and a subtraction circuit that extracts the difference between the forward axis maximum value and the reverse axis maximum value and obtains the number of passing axes and the passing direction from the value of this difference. It is something.

In a preferred embodiment of the invention, the detector is divided into three parts: a left, center and right detector.

The present invention will be explained below with reference to the drawings.

FIGS. 1 and 2 show the arrangement of the axis number detectors related to the present invention, and the second detector 2 is spaced apart from the second detector 2.

It is buried in a direction substantially perpendicular to the traveling direction of the road, that is, in the direction of the road width 1w, while maintaining the same.

Here is the interval. It is preferable to set the distance to be smaller than the length of the tread in the direction of travel of the vehicle.

Further, the detectors 1 and 2 are each divided into multiple sections in the direction of the road width 1w (in the example shown in FIG. 1, they are divided into three sections).

The case where the detector is divided into three will be explained below), and the length LL of each divided detector in the road width direction.

LC and LR shall be determined in such a way that they will not be pressed by the wheels on both sides of one axis of the vehicle at the same time.

That is, the lengths L L z Lo and LR are both set to be smaller than the inner rectangle of the tread width of the wheels on both sides of the one shaft.

In the following description, depending on the installation position of the divided detectors, subscripts C and R will be added to indicate the left, center, and right positions, respectively.

Next, each detector IL, IC, IR; 2L, 2C.

For example, 2R operates like a treadle contact, that is, it is normally in a non-conductive state, but when a wheel passes over the detector and is pressed by the wheel, it becomes conductive, and after the wheel passes, it becomes non-conductive again. It performs the action of returning to .

Therefore, the signal AIR from the first detectors IR, IC and 1L due to wheel suppression.

AIC and AIL are obtained respectively, and a signal A2R from the second detectors 2R, 2C and 2L.

A2C and A2L are obtained respectively.

FIG. 3 is a block diagram showing one embodiment of the axle number measuring circuit of the present invention, in which each detector 1R, IC, I
L; 2R, 2C, 2L outputs are input signals AIR, AIC
, A1L; A2R, A2C.

It becomes A2L, and the output signal is 2 Brigadier General X with multi-bind configuration.
The number of axles is determined by o=Xn, and the direction of travel of the vehicle is determined by the output Y.

The circuit configuration between the input and output and its basic operation will be explained below using FIG. 3.

The detection signals AIR and A2B of the right side detectors 1R and 2R of the divided detectors are added to the traveling direction determination circuit 3R, and depending on the phase relationship between these rain detection signals A1R and A2B, which signal is input first. The direction of travel of the wheels is determined by detecting the height of the vehicle.

For example, if signal AIR occurs before signal A2R, it will indicate a forward pass.

Further, the rain detection signals 1R and 2R are supplied to a one-shot pulse generator 5R via an OR gate 4R, and a counting pulse A is generated after the wheels have passed through the right side detector JR or 2R.

This counting permission pulse A is applied to the first and second AND gates 6
In addition to one input terminal of R and γR, the other input terminal receives the traveling direction output from the traveling direction determining circuit 3R, that is, the forward determining output B and the backward determining output C, and the first AND gate 6R outputs the traveling direction output from the traveling direction determining circuit 3R. A forward count pulse D is obtained, and a backward count pulse is obtained from the second AND gate γR.

The forward count pulse D is supplied to the right forward shaft circumference counter 8R, and the backward count pulse E is supplied to the right reverse shaft circumference counter 9R.

As a result, the counter 8R or 9 corresponding to the direction of travel
Only R counts count pulses D or E.

It is assumed that the traveling direction determination circuit 3R is reset to the state before the wheel enters by a reset signal (not shown) activated at the end of the counting pulse.

The above is the configuration of the measurement circuit corresponding to the right side detectors 1R and 2R, and the center and left side detector ICs.

A similar measurement circuit is configured for 2C, IL, and 2L as shown in the figure, and when the wheel passes over each of the right, center, and left detectors, a forward axis counter 8R, 8C and 8L or reverse axis counter 9R
, 9C and 9L, respectively.

The respective outputs of the forward axis counters 8R, 8C, and 8L described above are supplied to the forward axis circumference maximum value detection circuit 10, which can be configured with a digital comparator, to extract the forward axis maximum value F. ○Similarly, the forward axis circumference maximum value F is extracted. The respective outputs of the counters 9R, 9C, and 9L are supplied to a reverse shaft circumference maximum value detection circuit 11, which can be constituted by a digital comparator, to extract the reverse shaft maximum value G.

These maximum value outputs F and G are added to the subtraction circuit 12, and the reverse axis maximum value G is subtracted from the forward axis maximum value F. If the subtraction result is a positive value, the output signal Y indicates that the forward passage is being made. For example, it is indicated by the logical value "O", and the number of passing axes is taken out in the form of a multi-bit double inverted symbol Xo=Xn.

Furthermore, if the subtraction result is a negative value, the output signal Y indicates a logical value of 61'' indicating that the vehicle is passing in reverse.

The above operation is performed every time the wheel completely passes the detector ↓, and at the same time, a reset signal (not shown) that operates at the end of the counting pulse is used to determine the traveling direction of the circuit 3.
R, 3C and 3L are reset and return to the state before wheel entry.

By using a vehicle separation signal (not shown) obtained by detecting the presence or absence of a vehicle body, the number of axles and traveling direction of one vehicle can be automatically measured as described above.

Figure 4 shows one passing mode that occurs when the vehicle approaches the vehicle, and when the left wheel first moves forward, the left detector 1
Pass through the gap between L and 2L and the central detectors 1C and 2C, that is, the dividing part, and reach position A. Next, press the central detectors 1C and 2C to retreat and reach the position opening, and then the second time. When moving forward, only the left side detectors 1L and 2L are pressed to reach the position.

The right wheel advances only the right detectors 1R and 2R,
Move back, then move forward again, from position A through the mouth to position 8 as shown.

Table 1 shows the results of measurements made using the circuit shown in Figure 3 for such a parking lot.

As can be seen from Table 1, in the case of width closing in this example, the maximum value of the forward axis is 2 and the maximum value of the reverse axis is 1, so the number of passing axes is +1, which indicates that the X and Y outputs have moved forward. It can be seen that the measurement is performed along the actual axis of passage.

According to the present invention, a forward axis counter and a backward axis circumference counter are set for each division unit of the multi-divided detector using signals from the multi-divided axes number detector as detailed above. Each time a wheel passes, +1 is added to the forward axis side counter of the detector of the corresponding division unit if it is passing forward, and +1 is added to the forward axis side counter of the detector of the corresponding division unit if it is passing backward. Add +1 to the lap counter, compare the contents of the counters for the forward axis side counter and backward axis counter of each detector to find the maximum value, and calculate the number of passed axes by subtracting the maximum value of the forward axis and the maximum value of the backward axis. Since the measurement circuit has been logically configured in such a way, there is no need to newly install a joint detector to detect when a wheel passes through the divided portion of each detector, and it is possible to detect not only the passing state during normal driving but also the passing state in Fig. 4. It is possible to more accurately measure the number of passing axes and the passing direction even in the special passing manner as shown.

Therefore, the present invention is extremely suitable for vehicle identification devices installed at expressway entrance/exit gates, parking lot entrances, and the like.

In addition, the present invention is extremely effective when applied to a measuring circuit that counts the number of complicated-shaped items transported by a conveyor.

[Brief explanation of drawings]

1 and 2 are layout diagrams showing the arrangement of the multi-division detector in the present invention, FIG. 3 is a block diagram showing the circuit configuration of an embodiment of the number of axes measuring circuit of the present invention, and FIG. FIG. 4 is an explanatory diagram of a passing form when a vehicle is biased. 1 (IL, IC, IR); 1st detector, 2 (2L. 2C, 2R); 2nd detector, 3R, 3C, 3L; Traveling direction determination circuit, 4R, 4C, 4L; OR gate, 5R, 5
C, 5L; One-shot pulse generator, 6R, 6C, 6
L, γR2γC1γL; and gate, 8R, 8C, 8
L: Forward shaft side counter, 9R, 9C, 9L: Reverse shaft circumference counter, 10: Forward shaft circumference maximum value detection circuit, 11: Reverse shaft circumference maximum value detection circuit, 12: Subtraction circuit.

Claims (1)

[Claims] 1. A vehicle that measures the number of axles of passing vehicles by installing two multi-segmented detectors that detect wheel information by pressing the wheels in parallel in a direction substantially perpendicular to the traveling direction of the road. In the axle number measuring circuit, a traveling direction discriminating circuit receives the detection output from the detector for each division unit of the multi-divided detector and identifies the traveling direction of the wheel; a pulse generation circuit that receives detection outputs from the nuclear detector and generates one pulse when the wheel completes passing through the nuclear detector; and a forward discrimination output from the traveling direction discrimination circuit and one pulse from the pulse generation circuit. a forward shaft circumference counter that receives pulses from the pulse generator and changes the counting content by +1; and a reverse movement discrimination output from the traveling direction discrimination circuit; a maximum value detection circuit that detects the maximum value of the counts of the forward axis circumference counter and the reverse axis counter to obtain the forward axis maximum value and the reverse axis maximum value; A circuit for measuring the number of axes of a vehicle, comprising a subtraction circuit that extracts the difference between the maximum value of a forward axis and the maximum value of a reverse axis, and obtains the number of passing axles and the passing direction from the value of this difference. 2. A vehicle axle number measuring circuit according to claim 1, characterized in that the detector is divided into three units: a left side, a center, and a right side detector.