JP2000314654A - Device for measuring axle load of running automobile - Google Patents

Abstract

PROBLEM TO BE SOLVED: To measure an axle load of a running automobile by laying a step plate heading its top end (free end) to the running direction upstream as a cantilever, detecting the variation quantity of the separation width between the sensor head arranged immediately below it and the step plate and comparing it with a value measured in advance. SOLUTION: In a dent part 1 provided in a running path (road) of automobiles, a metal base 3 is fitted and fixed with anchor bolts 5 to the foundation concrete 4. An end of a step plate 10 is fixed with bolts to receptors 7 in the running direction downstream of the base 3 and the top end 10a of the upstream is made free to support as a cantilever. When a wheel of a running shaft run on the step plate 10, the step plate 10 bends due to the weight of the wheel. The bent varies from the initiation of passing of the wheel through the step plate 10 to the recovery to the original state and appears as the variation of the separation width between a displacement sensor head 13A placed below and the step plate 10. Therefore, the maximum variation is converted into electric signal and input in an operation means 15, compared with the measured data and output to an indication means as an axle load.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an axle load measuring device for measuring the axle load of a running automobile.

[0002]

2. Description of the Related Art Various types of axle meters using a load cell have been proposed as axle meters for measuring the axle load of an automobile. In any case, an automobile is arranged on a tread plate in a state close to a stopped state. It is the present condition that it measures.

[0003]

In recent years, tollgates on highways have been introduced with a system capable of collecting tolls without stopping the car.
And if the axle load can be measured, it will greatly contribute to society, such as alleviating traffic congestion, protecting the road surface, and preventing car accidents due to overloading.

[0004] Knowing the axle load on the road surface is also an important matter for maintenance of the traveling road.

[0005] The present invention is to solve such a problem by making it possible to measure the axle load even while the vehicle is running.

[0006]

SUMMARY OF THE INVENTION A tread plate is provided in a cantilever shape with a tip portion located on the traveling path of an automobile at an upstream side in the traveling direction of the automobile, and a sensor head is provided immediately below the tip portion of the tread plate. A displacement sensor that is arranged and converts the maximum value of the change amount of the separation width with the tread plate into an electric signal and outputs the electric signal;
Basically, it comprises an arithmetic means for comparing and calculating the electric signal from the displacement sensor and the actually measured value data stored by the storage means, and a display means for displaying a signal from the arithmetic means as an axial load of the vehicle. Means.

By using a displacement sensor which converts the change time of the separation width into an electric signal and outputs the signal together with the maximum value of the change amount of the separation width from the tread plate, the axle load at the time of stopping the vehicle is measured. it can.

[0008]

When a wheel rides on a tread while the vehicle is running, the tread is bent by receiving the load of the wheel because the tread is in a cantilever shape. It changes until it returns to the original state at the time of the start, and the change appears as a change in the separation width between the head of the displacement sensor disposed immediately below the tread plate and the tread plate,
The displacement sensor converts the maximum value of the change amount into an electric signal and outputs the electric signal to the calculating means. The calculating means compares the measured value data with the actually measured value data and outputs the electric signal to the display means as the axle load of the vehicle. .

[0009]

1 shows an embodiment of an axle measuring device for a traveling vehicle according to the present invention. FIG. 1 is a schematic explanatory view, and FIG. 2 is a plan view showing the relationship between a tread plate and a displacement sensor.

In the drawing, reference numeral 1 denotes a concave portion provided on a running path (road) 2 of an automobile, and a base 4 made of metal is fitted into the concave portion 1 to form a base concrete 4. The anchoring bolt 5 is attached to the base 3, and the base 3 is provided with a restricting portion 6 at one end on the upstream side in the traveling direction of the vehicle on the traveling path 2, and a supporting portion 7 at the other end on the downstream side corresponding to the restricting portion 6. Each of the bases 3 is provided with a projecting ridge 9 provided on the lower surface thereof with an engaging groove 8 formed on the upper surface of the supporting member 7. One end of 10 is placed and fixed by a fastening rod 11.

The reason why the ridge 9 is engaged with the engagement groove 8 is that the movement of the step plate 10 in the running direction is enhanced by reinforcing the fixing of the step plate 10 to the base 3 (receiving portion 7) by the fastening rod 11. This is because the displacement is more reliably regulated, and the mounting accuracy of the base 3 and the footboard 10 is increased.

The tread plate 10 is cantilevered by fixing the base end on the downstream side in the traveling direction to the receiving portion 7 of the base 3 as described above, and freeing the distal end 10a on the upstream side in the traveling direction. And is laid at an appropriate position on the traveling path 2 so as to be supported by the base 3, and is located on the upstream side in the traveling direction of the space 12 formed by the tread 10 and the base 3, that is, the tread 10.
The sensor head of the central displacement sensor 13A (hereinafter, referred to as the head) is arranged on the side of the front end 10a so as to be directly below the side of the stepping plate front end 10a and arranged in the width direction with respect to the running direction.
(Center sensor head) 13A 'and left and right displacement sensors 13
B and 13C (hereinafter, left and right sensor heads) 13B 'and 13C' are provided.
3A ', 13B', 13C 'and the stepping plate 10 so that the separation gap is maintained (the displacement sensor heads 13A, 13B,
13C is not pressed against the lower surface of the tread plate 10 so that it does not break.
Is provided to maintain the separation gap.

The center sensor head 13A ', the left sensor head 13B' and the right sensor head 13C 'together with the tread plate 10 constitute an axial load detecting section A, and the detecting section A (sensor heads 13A', 13B ', 13C'). ) Is a computing means 15 disposed in the vicinity of the detection unit A, that is, outside the traveling path 2.
The arithmetic means 15 is electrically connected to a display means 16 for displaying a signal from the arithmetic means 15 as an axial load of the vehicle.

The center sensor head 13A ', left sensor head 13B', and right sensor head 13C 'constitute the displacement sensors 13A, 13B, 13C together with an amplifier unit incorporated in the calculating means 15.

As the displacement sensor, an eddy current type, an optical type, an ultrasonic type and the like are known, but an eddy current displacement meter is used in this embodiment in consideration of a use environment and easy adjustment from outside. .

Incidentally, an eddy current displacement sensor is such that a high-frequency current flows through a coil inside a sensor head, and a high-frequency magnetic field is generated from the tip of the sensor head. The impedance of the sensor coil changes according to the distance, and this change is converted into an electric signal such as a voltage or a current, and the distance is measured. The resolution of 1 μm and the response speed of 10 KHz are cleared. It corresponds to.

The calculating means 15 also incorporates a pulse transmitter 17 and a pulse counter 18 for converting a wheel passing on the tread plate 10 into time (the pulse transmitter 17 and the pulse counter 18 constitute an encoder). As described above, the load is calculated by a numerical value that is connected to the sensor heads 13A ', 13B', and 13C 'via an amplifier unit and transmitted as an electric signal via the amplifier unit (this value is the load on the road surface). Further, the number of pulses from when the displacement starts to when the displacement returns to the original displacement amount is calculated to calculate the traveling speed of the automobile.

Further, by calculating the load and the speed, the axle load of the running automobile is calculated. The calculated axle weight is configured to be visible on a numerical display, a printout, or the like, by a display unit 16 connected to the arithmetic unit 15 via a cable.

Thus, the tread plate 10 laid on the traveling path 2
The sensor heads 13A 'and 13B are caused by temperature changes, deformation due to addition, and vibrations caused by vehicles running in the vicinity.
, 13C 'is constantly changing.

The three displacement sensors 13A, 13A,
13B, 13C sensor heads 13A ', 13B', 1
3C 'is attached so that the gap with the tread plate 10 is uniform at the time of assembly, but the numerical values indicated by the respective displacement sensors 13A, 13B, 13C when actually installed are different from each other.

For this purpose, the displacement sensor 13A of the central sensor head 13A 'is used as a master,
Of the other two displacement sensors 13B, 1
From the measured data of 3C, the numerical value relating to the vibration is canceled, and the left and right displacement sensors 13B,
It has a role of determining the displacement start point of 13C.

Left and right displacement sensors 13B, 1 used for actual measurement
In 3C, the sum of the maximum values of the displacement amounts is a numerical value related to weight.

The vibration of the road surface is the movement of the tread plate 10 up and down. The displacement is measured as an increase or decrease. During this time, the wheels are not on the tread plate 10 and the three displacement sensors 13
It is considered that the difference between the displacement amounts of A, 13B, and 13C is substantially the same.

The center displacement sensor 13A calculates backward from the end of this measurement and calculates the displacement amount for several times as the average value of the vibration.
In addition to successively storing, the other two displacement sensors 13B, 1
Compare the displacement with 3C.

When the wheel is mounted on the tread plate 10, the sensor heads 13A ', 13B', and 13C 'detect the displacement of the tread plate 10 only in the squat direction, and the displacement sensors 13A, 13B.
B and 13C show the values restored after reaching the maximum value by the forward movement of the wheel.

At this time, the master sensor (center sensor 13A) exceeds a predetermined value with respect to the average value stored immediately before or the difference between the displacement amounts of the other sensors 13B and 13C is constant. Will not keep.

Here, the central displacement sensor 13A does not perform subsequent measurement, but uses it as a signal to start measurement to the other displacement sensors 13B and 13C.

The displacement amount detected by the left and right displacement sensors 13B and 13C is calculated by calculating the sum of the difference between the numerical values at the time when the signal from the central displacement sensor 13A is obtained from the maximum value. The calculation means 15 calculates as a numerical value for this.

The pulse count is calculated by the left and right displacement sensors 13.
B and 13C, the counting is started for the left or right displacement sensor whose comparison difference with the displacement amount of the gap detected by the central displacement sensor 13A as the master sensor first exceeds a certain amount. The left and right displacement sensors 13B are counted until the displacement amount of the gap detected by the displacement sensor returns to the value at the time when the signal of the central displacement sensor 13A is obtained, and the count number (time) is set as the speed. ,
The sum of the numerical values of 13C and the calculating means 15 are calculated.

Since the arithmetic expression greatly varies depending on the material, dimensions, shape, etc. of the apparatus, it is determined by performing actual measurements. The value replaced as the traveling speed in the present device does not affect the magnitude of the wheel outer diameter.

When the wheel stops on the detection section A, the displacement sensors 13A, 13B, and 13C do not return to the amount of displacement at the start of measurement, so that pulse counting is continued. Since it is a phenomenon that occurs only in the load, it may be displayed by calculating only the load.

When the apparatus according to the embodiment is put into an operating state (the calculating means 15 assembles the members, that is, measures the data after installing the apparatus and stores the measured data by the storage means), the displacement sensors 13A , 13B, and 13C convert the respective separation gap widths between the sensor heads 13A ', 13B', and 13C 'and the tread plate 10 into electric signals through the sensor heads 13A', 13B ', and 13C' to calculate the operation means 1.
Send to 5.

At this time, the wheels of the traveling vehicle are
When stepping on the step, the step board 10 bends under the load, and the bending changes the separation gap width. When the central sensor head 13A 'detects the changed separation gap width, the calculating means 15 receiving this signal causes the respective separation gap widths (changed) input through the left sensor head 13B' and the right sensor head 13C '. Compare with
As a result, the pulse counter 18 starts pulse counting based on the numerical value of the separation gap width of the displacement sensor having the larger value of the separation gap width (changed to a value larger than the central displacement meter 13A), for example, the left displacement sensor 13B. On the other hand, when the wheel reaches directly above the left and right sensor heads 13B 'and 13C' (at the same time or at different times), the arithmetic means 1 generates a signal of the maximum value of the change amount (separation gap width) of the left and right displacement sensors 13B and 13C.
In response to this, the calculation means 15 calculates the sum of the maximum values, compares the calculated value with the actually measured data stored in the storage means, and displays the result on the display means 16 as the axle load when the vehicle is running.

When the center displacement sensor 13A returns to the value of the separation gap width at the start of the pulse count due to the movement of the wheel on the tread plate 10 (when the deflection of the tread plate 10 returns at the start of the pulse), the count time is measured. The data is compared and displayed on the display means 16 as the speed of the wheel (vehicle), and the sum of the count time and the maximum value is similarly calculated and compared with the actually measured data to display the axle load in the stopped state of the vehicle. 16 is displayed.

In the figure, reference numeral 20 denotes a drainage channel for preventing accumulation of rainwater.

[0036]

The present invention has the configuration described above,
The axle load during running and the axle load when stopped can be measured.

[Brief description of the drawings]

FIG. 1 is a schematic explanatory view.

FIG. 2 is a plan view showing a relationship between a tread plate and a displacement sensor.

[Explanation of symbols]

 2 Running path 10 Tread plate 10a Tip 13A ', 13B', 13C 'Sensor head 13A, 13B, 13C Displacement sensor 15 Calculation means 16 Display means

Claims (2)

[Claims] 1. A stepping plate having a tip portion located on an upstream side in a traveling direction of the vehicle in a traveling path of the vehicle and laid in a cantilever manner, and a sensor head disposed immediately below the tip portion of the stepping plate. A displacement sensor that converts the maximum value of the change amount of the separation width from the tread plate into an electric signal and outputs the electric signal; and an arithmetic unit that compares the electric signal from the displacement sensor with actual measurement value data stored by a storage unit, and Display means for displaying a signal from the arithmetic means as the load on the axle of the vehicle. 2. The shaft of a traveling vehicle according to claim 1, wherein the displacement meter converts the change time of the separation width into an electric signal and outputs the signal together with the maximum value of the change amount of the separation width from the tread plate. Weight measurement device.