JP2015222180A - Vehicle weight scale - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a vehicle weight scale capable of more appropriately detecting a measurement abnormality of the vehicle weight than the conventional art.SOLUTION: A vehicle weight scale 100 includes: a platform 20 on which a vehicle 10 is mounted; load cells DLC1-DLC4 for supporting the platform 20 from below; and a controller 30 for calculating the weight of the vehicle 10 on the basis of the output values of the load cells DLC1-DLC4 when the vehicle 10 is mounted on the platform 20. The controller 30 determines the leaving of the vehicle 10 from the platform 20 on the basis of the output values, and determines the presence/absence of a measurement abnormality of the vehicle weight by comparing the output values of the load cells DLC1-DLC4 after the leaving of the vehicle 10 with the initial values of the load cells DLC1-DLC4.

Description

  The present invention relates to a vehicle weighing scale.

  There is a pit type truck scale as a vehicle weighing scale. In this truck scale, a plurality of load cells and a platform supported by the load cells are arranged in a concrete pit formed by digging the ground. Thereby, the weight of the vehicle and the like can be measured by placing the vehicle such as a truck traveling slowly on the ground on the platform.

  By the way, various proposals have conventionally been made regarding the prevention of abnormal measurement of the vehicle weight of a truck scale.

  For example, a measure against a measurement abnormality that occurs when the edge of the platform comes into contact with the inner wall of the pit due to an impact caused by a sudden entry of the vehicle on the platform is proposed (see Patent Document 1). Specifically, Patent Document 1 describes a detection switch that detects that an edge of a mounting table contacts or approaches an inner wall of a pit.

  In Patent Document 2, a failure diagnosis system that outputs a warning signal when a load pattern at the time of measuring a vehicle weight using a truck scale changes and when a change in a measurement reference value when the truck scale is not loaded exceeds an allowable range. Is described.

  Patent Document 3 describes a measuring device that detects wheel disengagement from the track scale of the vehicle by comparing the number of wheels of the vehicle with the number of wheel shafts getting on and off the track scale.

JP 2012-127841 A JP-A-5-322637 JP 2008-164316 A

  However, in the conventional example, the cause of the abnormal measurement of the vehicle weight in the vehicle scale such as a truck scale has not been sufficiently studied.

  An aspect of the present invention has been made in view of such circumstances, and an object of the present invention is to provide a vehicle weighing scale that can appropriately detect an abnormality in measurement of the vehicle weight as compared with the conventional one.

  A vehicle weighing scale according to an aspect of the present invention includes a platform on which a vehicle is mounted, a load cell that supports the above-described table from below, and an output value of the load cell when the vehicle is on the table. A controller for calculating the weight of the load cell, wherein the controller determines whether the vehicle has exited from the table described above based on the output value, and outputs the load cell output value and the load cell after the vehicle exits. The presence or absence of a vehicle weight measurement abnormality is determined by comparison with the initial value.

  According to one aspect of the present invention, it is possible to obtain a vehicle weighing scale that can appropriately detect an abnormality in the measurement of the vehicle weight as compared with the related art.

FIG. 1 is a diagram illustrating an example of a track scale according to the embodiment. FIG. 2 is a block diagram illustrating an example of a track scale control system according to the embodiment. FIG. 3 is a diagram illustrating an example of functional blocks of the track scale controller according to the embodiment. FIG. 4 is a diagram illustrating an example of an output waveform of the load cell in the track scale of the embodiment. FIG. 5 is a diagram for explaining an example of the cause of the vehicle weight measurement abnormality. FIG. 6 is a block diagram illustrating an example of a track scale control system according to a first modification of the embodiment. FIG. 7 is a diagram illustrating an example of a track scale according to a third modification of the embodiment.

(Embodiment)
The present inventors diligently studied the cause of abnormal measurement of vehicle weight in vehicle scales such as truck scales, and obtained the following knowledge.

  In this type of vehicle weight scale, for example, a load (for example, gravel or stone) loaded on the vehicle may spill from the vehicle due to an impact when the vehicle gets on the platform or when the vehicle leaves the platform. At this time, a load such as gravel or stone may enter the gap between the platform and the pit or the gap between the platform and the load cell. If the vehicle is weighed with the vehicle weight meter in this state, the vehicle weight may be abnormally measured due to contact between the platform and the pit due to the load fitted in the gap. Also, in this state, the controller of the vehicle weighing scale performs zero point correction by the automatic zero point correction function after leaving the vehicle from the platform, and loads from the gap due to the impact when the vehicle enters the platform next time. If it deviates from this, it will cause a measurement error of the vehicle weight.

  Therefore, the vehicle weighing scale according to the first aspect of the present invention is based on the platform on which the vehicle is mounted, the load cell that supports the platform from below, and the output value of the load cell when the vehicle is on the platform. A controller for calculating the weight, and the controller determines exit from the vehicle platform based on the output value, and compares the output value of the load cell after leaving the vehicle with the initial value of the load cell. Then, the presence / absence of an abnormality in measuring the vehicle weight is determined.

  With this configuration, it is possible to appropriately detect an abnormality in measurement of the vehicle weight as compared with the conventional case.

  The vehicle weight scale according to the second aspect of the present invention is the vehicle weight scale according to the first aspect, wherein the controller acquires the output values and the initial values of the plurality of load cells in a one-to-one correspondence. Thus, by comparing each output value of the load cell after leaving the vehicle and each initial value of the load cell, it is determined whether there is a measurement abnormality of the vehicle weight measured by the corresponding load cell.

  From such a configuration, for example, contact between the loading platform and the pit due to the load fitted in the gap near the first load cell, or contact between both due to the loading fitted in the gap between the loading table and the first load cell. Thus, it can be appropriately detected that there is a measurement abnormality of the vehicle weight measured by the first load cell.

  Further, the vehicle weighing scale according to the third aspect of the present invention is the vehicle weighing scale according to the first or second aspect, wherein the controller has a difference between the output value of the load cell after leaving the vehicle and the initial value of the load cell, If it is equal to or greater than the predetermined value, a warning is given that there is an abnormality in the measurement of the vehicle weight.

  With such a configuration, it is possible to know a vehicle weight measurement abnormality in a timely manner.

  Further, the vehicle weighing scale according to the fourth aspect of the present invention is the vehicle weighing scale according to the first aspect, provided with pits surrounding the rectangular platform in plan view, and the load cells are respectively provided at the four corners of the platform. The controller obtains the output value and the initial value of the load cell in a one-to-one correspondence with each other, and if there is a vehicle weight measurement abnormality, the output value and Using the initial value and the size of the mounting table, the location of the loading that fits in the gap when the load that fits in the gap between the pit and the loading platform is assumed to be the cause of the vehicle weight measurement abnormality is predicted.

  With this configuration, it is possible to respond more quickly to vehicle weight measurement abnormalities than in the past.

  Hereinafter, specific examples of embodiments of the present invention will be described with reference to the drawings. In the following description, the same or corresponding elements are denoted by the same reference symbols throughout the drawings, and description of the overlapping elements may be omitted. Further, the present invention is not limited to the following specific examples.

[Track scale configuration]
FIG. 1 is a diagram illustrating an example of a track scale according to the embodiment. In the present embodiment, for the sake of convenience, the full length direction of the vehicle 10 is illustrated as the “front” and “rear” directions in FIG. The configuration of the track scale 100 will be described below assuming that the vehicle 10 enters from “rear” of the platform 20 and exits from “front” of the platform 20.

  As shown in FIG. 1, a truck scale 100, which is an example of a vehicle weight scale, includes a platform 20 on which a vehicle 10 such as a truck or a trailer is placed, a first load cell DLC1, a second load cell DLC2, a third load cell DLC3, and a fourth load cell. A load cell DLC4 (hereinafter, these load cells DLC1, DLC2, DLC3, and DLC4 may be abbreviated as “load cells DLC1 to DLC4”) and a controller 30.

  A six-wheel truck 10 is illustrated as the vehicle 10. That is, in this truck 10, one axle 11 (hereinafter sometimes abbreviated as “first shaft 11”) on which wheels 11a and 11b are mounted is arranged below the driver's seat, and the wheels 12a, 12b, 13a, Two rear axles 12 and 13 (hereinafter, may be abbreviated as “second shaft 12” and “third shaft 13”) on which 13b is mounted are arranged below the loading platform.

  When the track scale 100 is viewed in plan, a rectangular pit 26 is formed on the surface of the installation base (ground) 25. As shown in FIG. 1, a rectangular (rectangular) platform 20 and load cells DLC <b> 1 to DLC <b> 4 are arranged in the pit 26. The mounting table 20 is configured by a plate member having an end portion extending in the front-rear direction as a long side and a front end portion and a rear end portion orthogonal to the front-rear direction as short sides.

  Each of the load cells DLC1 to DLC4 supports the mounting table 20 from below at each of the four corners of the mounting table 20. Specifically, the first load cell DLC1 and the third load cell DLC3 are arranged at a predetermined interval on a straight line parallel to the rear end portion in the vicinity of the rear end portion of the mounting base 20, and the second load cell DLC2 and the fourth load cell DLC4 are In the vicinity of the front end portion of the mounting table 20, they are arranged on the straight line parallel to the front end portion at the same interval as the fixed interval.

[Track scale control system]
FIG. 2 is a block diagram illustrating an example of a track scale control system according to the embodiment.

  As shown in FIG. 2, the track scale 100 includes a controller 30, an operation device 40, and a display device 41. In the present embodiment, digital load cells DLC1 to DLC4 including an amplifier, an A / D converter, a CPU, an interface circuit, and the like (all not shown) are illustrated in addition to the load cell. Thereby, a digital signal can be directly output to the controller 30 from each of the load cells DLC1 to DLC4.

  The controller 30 includes an interface circuit 31, a calculation unit 32, and a storage unit 33.

  The interface circuit 31 has a function of exchanging various signals and data among the load cells DLC1 to DLC4, the operation device 40, the display device 41, and the calculation unit 32.

  The arithmetic unit 32 is configured by a processing device such as a microprocessor (CPU or MPU), for example, and receives necessary signals via the interface circuit 31 in accordance with instructions of a predetermined program stored in the storage unit 33. A function of receiving various data from the storage unit 33 and executing a calculation based on the received signals and data.

  The storage unit 33 is configured by, for example, a memory (PROM or RAM), and has a function of storing a predetermined program, basic data, or the like for a long time, or temporarily storing various data, numerical values for calculation, or the like. Prepare.

  The operation device 40 includes, for example, operation switches and numerical keys, and is used in various operations such as measurement start / end operations, zero point adjustment operations, use mode switching operations, and numerical value setting operations.

  The display device 41 is composed of, for example, a liquid crystal display panel or the like, and displays measurement results and input / output screens of various data.

[Track scale control system functions]
In the control system of the track scale 100, digital signals output from the load cells DLC 1 to DLC 4 are sent to the arithmetic unit 32 via the terminal box 34 and the interface circuit 31. Specifically, each of the load cells DLC1 to DLC4 includes an identification number. When the data request with the identification number is sent from the computing unit 32 to the load cells DLC1-DLC4, the load signal DLC1-DLC4 with the identification number corresponding to the data request receives a weight signal (digital signal) along with the identification number. It is output to the calculation unit 32.

  As described above, the calculation unit 32 calculates various useful information that can support the driving of the truck 10 based on the weight signal and the data stored in the storage unit 33, and the calculation result is displayed on the display 41. The

  For example, as shown in FIG. 3, in the track scale 100 of the present embodiment, the controller 30 executes a predetermined program in the arithmetic unit 32, thereby calculating the weight of the truck 10. The functions of the number-of-axes calculation unit 51 for calculating the number of axles 11, 12, and 13, the measurement abnormality determination unit 52 that determines the measurement abnormality of the vehicle weight measured by the load cells DLC 1 -DLC 4, and the display signal generation unit 53 Realized.

  Note that the controller 30 does not necessarily need to be configured as a single controller, and a plurality of controllers are arranged in a distributed manner, and they are configured to control the operation of the track scale 100 in cooperation with each other. May be. For example, an example in which the function of the weight calculation unit 50, the function of the axis number calculation unit 51, and the function of the measurement abnormality determination unit 52 is realized by using a single controller 30 is described. The function may be realized using a separate controller.

  Hereinafter, the function of the weight calculation unit 50, the function of the axis number calculation unit 51, and the function of the measurement abnormality determination unit 52 of the controller 30 will be described in order.

[Definition of symbols]
First, the meanings of symbols used in the following description and related drawings are collectively defined.

<Platform related>
L: The length of the long side of the mounting table 20 (lateral dimension of the mounting table 20)
M: Length of short side of mounting table 20 (vertical dimension of mounting table 20)

<Load cell output-related>
W: Weight of the truck 10 W ₁ : Component of the first load cell DLC 1 in the weight of the truck 10 P ₁ : Output value of the first load cell DLC 1 P ₂ : Output value of the second load cell DLC 2 P ₃ : Output value of the third load cell DLC 3 P ₄ : Output value of fourth load cell DLC 4 P: Sum of output values of all load cells DLC 1 -DLC 4 (P = P ₁ + P ₂ + P ₃ + P ₄ )
W ₁₀ : output value of the first load cell DLC1 before the truck 10 enters the mounting 20 (initial value of the first load cell DLC1)
W ₂₀ : Output value of the second load cell DLC2 before the truck 10 enters the mounting 20 (initial value of the second load cell DLC2)
W ₃₀ : Output value of the third load cell DLC3 before the truck 10 enters the mounting 20 (initial value of the third load cell DLC3)
W ₄₀ : output value of the fourth load cell DLC4 before the truck 10 enters the mounting 20 (initial value of the fourth load cell DLC4)
W ₀ : Overall initial value (W ₀ = W ₁₀ + W ₂₀ + W ₃₀ + W ₄₀ )

<Load cell output waveform>
FIG. 4 is a diagram illustrating an example of an output waveform of the load cell in the track scale of the embodiment.

In FIG. 4 (a), the output waveform of the sum P of the output values of all the load cells DLC1-DLC4 shown, in FIG. 4 (b), the output waveform of the output value _{P 1} of the first load cell DLC1 is shown .

As shown in FIG. 4, in the respective tires of both wheels 11 a and 11 b of the first shaft 11 (the same applies to the second shaft 12 and the third shaft 13) of the truck 10, between the installation base 25 and the mounting base 20. A tire contact surface is formed, and the tire has a tire contact length. Therefore, when the truck 10 gets on the platform 20 and then exits, the output signal waveform of the load cells DLC1 to DLC4 has a plurality of break points as shown in FIG. The times t ₁ , t ₂ , t ₃ , t ₄ , t ₅ , t ₆ , t _ss , t _sf , and t _f corresponding to can be defined as follows.

t ₁ : When the tires of the wheels 11 a and 11 b of the first shaft 11 get on the mounting table 20 t ₂ : When the tires of the wheels 12 a and 12 b of the second shaft 12 get on the mounting table 20 t ₃ : Third wheels 13a of the shaft 13, 13b tire is, when riding on the platform 20 t _4: wheel 11a of the first shaft 11, 11b tire is t ₅ when the exit from the platform 20: the wheel of the second shaft 12 12a, 12b tire is, t ₆ when the exit from the platform 20: the wheels 13a of the third shaft 13, 13b tire is, t _ss when exiting from the platform 20: the wheels 13a of the third shaft 13, 13b of the When the stability waiting time of the load cells DLC1-DLC4 has elapsed since the tires got on the platform 20 t _sf : When the tires of the wheels 13a and 13b of the third shaft 13 start to leave the platform 20 t _t : The wheels 13a and 13b of the third shaft 13 When ya is, stabilization wait time of the load cell DLC1-DLC4 from the time of exit from the platform 20 has elapsed

[Function of axis number calculation unit]
Hereinafter, the function of the axis number calculation unit 51 of the controller 30 will be described.

As shown in FIG. 4 (a), when the tires of the wheels 11a and 11b of the first shaft 11 start to get on the platform 20, the impact of the truck 10 on the platform 20 is affected by the P (x ) began rising edge of the output waveform shows a maximum value at time t _1. When the tires of the wheels 11a and 11b of the first shaft 11 are completely on the platform 20, the value of the output waveform becomes constant.

  Thereby, the number-of-axis calculation unit 51 can detect that the tires of the wheels 11a and 11b of the first shaft 11 are on the platform 20 based on the output waveform of P (x). Similarly, the number-of-axis calculation unit 51 determines that the tires of the wheels 12a and 12b of the second shaft 12 and the tires of the wheels 13a and 13b of the third shaft 13 are based on the output waveform of P (x), respectively. Can be detected.

On the other hand, when the tires of the wheels 11a and 11b of the first shaft 11 of the truck 10 start to leave the platform 20, the output waveform of P (x) falls due to the impact when the truck 10 leaves the platform 20 First, it shows a minimum value at time _{t 4.} When the tires of the wheels 11a and 11b of the first shaft 11 are completely withdrawn from the platform 20, the value of the output waveform is constant.

  Thereby, the number-of-axis calculation unit 51 can detect that the tires of the wheels 11 a and 11 b of the first shaft 11 have left the mounting base 20 based on the output waveform of P (x). Similarly, the number-of-axis calculation unit 51 determines that the tires of the wheels 12a and 12b of the second shaft 12 and the tires of the wheels 13a and 13b of the third shaft 13 are based on the output waveform of P (x), respectively. It can be detected that the user has left.

As described above, in the track scale 100 according to the present embodiment, the axis number calculation unit 51 determines the number of maximum values or the number of minimum values in the time interval [t ₁ , t ₆ ] based on the output waveform of P (x). The number of axes of the track 10 can be detected by counting.

[Function of weight calculation unit]
Hereinafter, the function of the weight calculation unit 50 of the controller 30 will be described.

  As shown in FIG. 4, the weight W of the truck 10 can be derived from the following equation (1).

W = P (t) (= P ₁ (t) + P ₂ (t) + P ₃ (t) + P ₄ (t)) (1)
In equation (1), t is the time within the time interval [t _ss , t _sf ].

The weight calculator 50 can know the time interval [t _ss , t _sf ] by detecting the time t ₃ and the time t ₄ .

  As described above, in the track scale 100 of the present embodiment, the weight calculation unit 50 can calculate the weight W of the truck 10 using the equation (1).

[Function of measurement abnormality determination unit]
Hereinafter, the function of the measurement abnormality determination unit 52 of the controller 30 will be described.

  As described above, in the truck scale 100, for example, a load (for example, gravel or stone) loaded on the truck 10 due to an impact when the truck 10 enters the platform 20 or when the truck 10 leaves the platform 20. May spill from the track 10. At this time, a load such as gravel or stone may enter the gap between the loading table 20 and the pit 26 or the gap between the loading table 20 and the load cells DLC1-DLC4. In this case, it causes a measurement abnormality of the vehicle weight measured by the load cells DLC1-DLC4.

Therefore, the truck scale 100 of the present embodiment, the measurement abnormality determination unit 52 of the controller 30, by the detection of the time t _f as well as determine the exit from the platform 20 of the track 10, after exit of the track 10 (i.e., the output value of the load cell DLC1-DLC4 time _{t f} later), by comparing the initial value of the load cell DLC1-DLC4, determines the vehicle weight measurement abnormality presence or absence to be measured by the load cell DLC1-DLC4. The measurement abnormality determining unit 52 can know the time t _f from the axis number of the track 10 obtained by the above shaft speed computing unit 51.

Specifically, as shown in FIG. 4A, the measurement abnormality determination unit 52 includes the sum P (= P ₁ + P ₂ + P ₃ + P ₄ ) of the output values of the load cells DLC1 to DLC4 after leaving the track 10 and the load cell. difference G between the total initial value _{W 0} of DLC1-DLC4 is equal to or larger than the predetermined value, it is determined that the vehicle weight measurement abnormality exists that is measured by the load cell DLC1-DLC4. Moreover, the measurement abnormality determination part 52 determines with the measurement abnormality of the vehicle weight measured with the load cells DLC1-DLC4 not existing, when the said difference G is less than predetermined value.

  As described above, in the truck scale 100 of the present embodiment, it is possible to appropriately detect an abnormality in measurement of the vehicle weight measured by the load cells DLC1 to DLC4 as compared with the conventional case.

The initial values of the load cells DLC1 to DLC4 indicate the output values of the load cells DLC1 to DLC4 before the truck 10 gets on the platform 20, as described above. Therefore, the sum of the initial values of the load cells DLC1 to DLC4 corresponds to the overall initial value W ₀ (= W ₁₀ + W ₂₀ + W ₃₀ + W ₄₀ ).

The measurement abnormality determination unit 52, the difference G between the total initial value _{W 0} of the sum P and the load cell DLC1-DLC4 of the output value of the load cell DLC1-DLC4 after leaving the track 10 and is above a predetermined value, A warning is given that there is an abnormality in the measurement of the vehicle weight measured by the load cells DLC1-DLC4 using the display 41 or the like. Thereby, the measurement abnormality of the vehicle weight measured by the load cells DLC1-DLC4 can be known in a timely manner. The above warning may be performed by, for example, an alarm buzzer or a warning light instead of the display device 41 or together with the display device 41.

Further, the measurement abnormality determination unit 52 of the controller 30 has a _one-to-one correspondence between the output values P ₁ , P ₂ , P ₃ , P ₄ and the initial values W ₁₀ , W ₂₀ , W ₃₀ , W ₄₀ of the load cells DLC 1 -DLC _4. Acquired in association with. Then, the measurement abnormality determination unit 52, after exit of the track 10 (that is, after time _{t f)} each of the output value _P 1 of the load cell DLC1-DLC4 _{of, P 2, P 3, P} 4 and the respective load cells DLC1-DLC4 The initial values W ₁₀ , W ₂₀ , W ₃₀ , and W ₄₀ are compared to determine whether there is a measurement abnormality in the vehicle weight measured by the corresponding load cells DLC1-DLC4.

Specifically, when described in the first load cell DLC1, as shown in FIG. 4 (b), measuring the abnormality determination unit 52, the output value _{P 1} of the first load cell DLC1 after leaving the track 10 and the initial value of the first load cell DLC1 difference G ₁ and W ₁₀ is equal to or larger than the predetermined value, it is determined that the measurement abnormality of the vehicle weight which is measured by the first load cell DLC1 is present. Further, the measurement abnormality determination unit 52 determines the difference G ₁ is, if less than the predetermined value, the vehicle weight measurement abnormality exists measured by the first load cell DLC1.

  As described above, in the track scale 100 of the present embodiment, the contact between the loading table 20 and the pit 26 due to the load fitted in the gap S1 (see FIG. 5) in the vicinity of the first load cell DLC1, or the loading table 20 and the first loading cell DLC1. It is possible to appropriately detect the presence of an abnormality in the measurement of the vehicle weight measured by the first load cell DLC1 due to contact between the two due to the load fitted in the gap S2 (see FIG. 5) between the load cell DLC1 and the like.

(First modification)
In the above embodiment, the digital load cells DLC1 to DLC4 have been described. However, the present invention is not limited to this.

  For example, as illustrated in FIG. 6, an analog signal may be transmitted from each of the load cells LC <b> 1 to LC <b> 4 to the controller 30. In this case, the controller 30 includes an amplifier 35, a low-pass filter 36, an A / D converter 37, and the like corresponding to each of the load cells LC1 to LC4. The analog signal transmitted from the load cells LC1 to LC4 is amplified by the amplifier 35 to a size capable of A / D conversion. Further, the analog signal from the amplifier 35 is converted into a digital signal by the A / D converter 37.

(Second modification)
In the above embodiment, an example has been described in which the weight calculation unit 50 derives the weight W of the truck 10 by knowing the time interval [t _ss , t _sf ] by detecting the time t ₃ and the time t _4. Not limited to.

  For example, the operator may guide the weight W of the truck 10 by performing a weighing operation using the operating device 40 by visual confirmation.

(Third Modification)
In the above embodiment, the measurement abnormality determination unit 52 has described the example of determining the measurement abnormality of the vehicle weight measured by the load cells DLC1 to DLC4. However, the present invention is not limited to this.

  In this modified example, the location of the actual load when it is assumed that the load of gravel or stones fitted in the gap S1 between the mounting base 20 and the pit 26 is the cause of the vehicle weight measurement abnormality. The function to predict is given.

  FIG. 7 is a diagram illustrating an example of a track scale according to a third modification of the embodiment.

As shown in FIG. 7, the pit 26 surrounds the rectangular platform 20 in a plan view. That is, an annular elongated gap S <b> 1 is formed between the pit 26 and the mounting table 20 in plan view. As described above, the measurement abnormality determination unit 52 of the controller 30 outputs the output values P ₁ , P ₂ , P ₃ , P ₄ and the initial values W ₁₀ , W ₂₀ , W ₃₀ , W of the load cells DLC 1 -DLC _{4. 40} are acquired in a one-to-one correspondence.

  By the way, when a load such as gravel or stone is fitted in the gap S1 between the loading table 20 and the pit 26, the output of the load cell in the vicinity of the loading edge where the loading is fitted has a positive effect on the initial value. The load cell closer to the load has a greater effect.

Therefore, the following cases are considered in relation to the output values P ₁ , P ₂ , P ₃ , P _{4 of} the load cells DLC 1 -DLC ₄ and the initial values W ₁₀ , W ₂₀ , W ₃₀ , W ₄₀ .

(A) When P ₁ > W ₁₀ and P ₂ > W ₂₀ (however, P ₃ ≈W ₃₀ , P ₄ ≈W ₄₀ )
In this case, it can be determined that a load such as gravel or stone fits into the gap S1 corresponding to the area A in FIG. Therefore, the measurement abnormality determination unit 52 of the controller 30 uses the output values P ₁ and P ₂ and the initial values W ₁₀ and W ₂₀ of the load cells DLC 1 and DLC ₂ and the lateral dimension L of the mounting table ₂₀ as follows: (2), to predict the location _{L X} of the load that fits in the gap S1. Note that L _X corresponds to the distance in the front-rear direction from the corner of the mounting table 20 corresponding to the second load cell DLC2 to the load.

L _X = L × ((P ₁ −W ₁₀ ) − (P ₂ −W ₂₀ )) / ((P ₁ −W ₁₀ ) + (P ₂ −W ₂₀ ) (2)

(B) When P ₂ > W ₂₀ and P ₄ > W ₄₀ (however, P ₁ ≈W ₁₀ , P ₃ ≈W ₃₀ )
In this case, it can be determined that a load such as gravel or stone fits into the gap S1 corresponding to the region B in FIG. Therefore, the measurement abnormality determination unit 52 of the controller 30 uses the output values P ₂ and P ₄ and the initial values W ₂₀ and W ₄₀ of the load cells DLC 2 and DLC ₄ and the vertical dimension M of the mounting table 20 as follows: the (3), to predict the locations _{M Y} of the load that fits in the gap S1. Incidentally, M _Y corresponds to the distance perpendicular from the corners of the platform 20 corresponding to the fourth load cell DLC4 in the longitudinal direction to the load.

_MY = M × ((P ₂ −W ₂₀ ) − (P ₄ −W ₄₀ )) / ((P ₂ −W ₂₀ ) + (P ₄ −W ₄₀ ) (3)

(C) When P ₃ > W ₃₀ and P ₄ > W ₄₀ (however, P ₁ ≈W ₁₀ , P ₂ ≈W ₂₀ )
In this case, it can be determined that a load such as gravel or stone fits into the gap S1 corresponding to the region C in FIG. Therefore, the measurement abnormality determination unit 52 of the controller 30 uses the output values P ₃ and P ₄ and the initial values W ₃₀ and W ₄₀ of the load cells DLC 3 and DLC ₄ and the horizontal dimension L of the mounting table 20 as follows: (4), to predict the location _{L X} of the load that fits in the gap S1. Note that L _X corresponds to the distance in the front-rear direction from the corner of the mounting table 20 corresponding to the fourth load cell DLC4 to the load.

L _X = L × ((P ₃ −W ₃₀ ) − (P ₄ −W ₄₀ )) / ((P ₃ −W ₃₀ ) + (P ₄ −W ₄₀ ) (4)

(D) When P ₁ > W ₁₀ and P ₃ > W ₃₀ (however, P ₂ ≈W ₂₀ , P ₄ ≈W ₄₀ )
In this case, it can be determined that a load such as gravel or stone fits into the gap S1 corresponding to the region D in FIG. Therefore, the measurement abnormality determination unit 52 of the controller 30 uses the output values P ₁ and P ₃ and the initial values W ₁₀ and W ₃₀ of the load cells DLC 1 and DLC ₃ and the vertical dimension M of the mounting table 20 as follows: (5), to predict the locations _{M Y} of the load that fits in the gap S1. Incidentally, L _Y corresponds to the distance perpendicular from the corners of the platform 20 corresponding to the third load cell DLC3 in the longitudinal direction to the load.

M _Y = M × ((P ₁ −W ₁₀ ) − (P ₃ −W ₃₀ )) / ((P ₁ −W ₁₀ ) + (P ₃ −W ₃₀ ) (5)

In this way, when there is a vehicle weight measurement abnormality, the measurement abnormality determination unit 52 of the controller 30 outputs the output values P ₁ , P ₂ , P ₃ , P ₄ and the initial value W _{10 of the} load cells DLC1 to DLC4. , W ₂₀ , W ₃₀ , W _{40 and} the dimensions L and M of the mounting table 20, assuming that the load fitted in the gap S 1 between the pit 26 and the mounting table 20 is the cause of the abnormal measurement of the vehicle weight. Predict where the cargo will be loaded. Thereby, compared with the past, it can respond to the measurement abnormality of a vehicle weight rapidly.

For example, the controller 30 uses the above-described L _X or M _Y, may point to the location of cargo that fits the gap S1 on the display screen of the display unit 41. Then, the operator of the track scale 100 can quickly find a load such as gravel or stone fitted in the gap S1 with reference to the instruction content on this display screen, and as a result, the load fitted in the gap S1 can be found in the gap S1. Can be removed quickly.

  In addition, the said arithmetic expression is an illustration, Comprising: It is not limited to this example. For example, if the configuration of the load cell of the vehicle weighing scale is different, the output value of the load cell may be affected. Therefore, it is necessary to modify the arithmetic expression corresponding to it.

  According to one embodiment of the present invention, it is possible to appropriately detect an abnormality in measurement of the vehicle weight as compared with the conventional case. Therefore, one embodiment of the present invention can be used for, for example, a vehicle weighing scale.

10 Truck (vehicle)
11 Axle (first axis)
11a Axle (first axis) right wheel 11b Axle (first axis) left wheel 12 Axle (second axis)
12a Axle (second axis) right wheel 12b Axle (second axis) left wheel 13 Axle (third axis)
13a Axle wheel (third axis) right wheel 13b Axle wheel (third axis) left wheel 20 Platform 25 Installation base 26 Pit 30 Controller 31 Interface circuit 32 Calculation unit 33 Storage unit 40 Controller 41 Display unit 50 Weight calculation unit 51 Axis Number Calculation Unit 52 Measurement Abnormality Determination Unit 53 Display Signal Generation Unit DLC1 First Load Cell DLC2 Second Load Cell DLC3 Third Load Cell DLC4 Fourth Load Cell 100 Truck Scale (Vehicle Weight Scale)

Claims (4)

A loading table on which the vehicle rides, a load cell that supports the loading table from below, and a controller that calculates the weight of the vehicle based on an output value of the load cell when the vehicle rides on the loading table. ,
The controller determines whether the vehicle has left the preceding table based on the output value, and compares the output value of the load cell after leaving the vehicle with the initial value of the load cell to determine whether a vehicle weight measurement error has occurred. A vehicle weighing scale that determines the presence or absence.   The controller acquires the output values and initial values of the plurality of load cells in a one-to-one correspondence with each other, and outputs the output values of the load cells and the initial values of the load cells after leaving the vehicle. The vehicle weight scale according to claim 1, wherein the presence or absence of a measurement abnormality of the vehicle weight measured by the corresponding load cell is determined by comparison.   3. The controller according to claim 1, wherein when the difference between the output value of the load cell after leaving the vehicle and the initial value of the load cell is equal to or greater than a predetermined value, the controller warns that there is a vehicle weight measurement abnormality. Vehicle weight scale as described. In plan view, it has a pit surrounding the rectangular table described above,
Each of the load cells supports the front table from below at each of the four corners of the front table,
The controller acquires the output values and initial values of the load cells in a one-to-one correspondence, and if there is a measurement abnormality of the vehicle weight, the output values and initial values of the load cells and The location of the load that fits in the gap when the load that fits in the gap between the pit and the table is assumed to be the cause of the measurement error of the vehicle weight is predicted using the dimensions of the stand. Vehicle weighing scale as described in 1.

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