JP5751962B2 - Axle load scale - Google Patents

Description

  The present invention relates to a shaft weight scale. In particular, the present invention relates to an axle weight meter capable of guiding the wheel load and the center of gravity position of a vehicle such as a truck or trailer loaded with a load.

  It is well known that when a vehicle such as a truck or a trailer carries a load, the traveling state may become unstable depending on the loaded state. In particular, in a traveling state in which centrifugal force acts on the vehicle, the instability of the vehicle increases, and the main mechanical factors include vehicle speed, total weight, axle weight, wheel weight, and center of gravity position. it can.

  The deviation of the load in the vehicle width direction with respect to the vehicle center plane is called “single load”, and the deviation in the vehicle front-rear direction is called “preload” or “afterload”. These are said to be loading state quantities to be noted in the safe driving of the vehicle. The amounts that serve as an indicator of such a loading state are the wheel load and the axle load of the vehicle, which depend on the total weight of the vehicle and the position of the center of gravity. Therefore, if the wheel load and the center of gravity of the vehicle can be derived using the axle load meter in addition to the total weight and axle load of the vehicle, it is beneficial for driving the vehicle. In the vehicle restriction ordinance, the axle load is defined as 10 tons or less and the wheel load is defined as 5 tons or less.

  By the way, conventionally, the amount that can be accurately measured using the axle load meter is the total weight and axle load of the vehicle, and it is difficult to measure the wheel load and the center of gravity.

  In view of this, there has already been proposed an axle weight meter that includes a pair of left and right weight scales (wheel weight scales) and can guide the position of the center of gravity of the vehicle (for example, see Patent Document 1).

Japanese Patent Laid-Open No. 6-58796

  However, the axle load meter described in Patent Document 1 has the following problems.

  First, the axle weight meter of Patent Document 1 requires a pair of weight meters. Therefore, the number of parts of the mounting table and the load cell is increased as compared with the case where a single weighing scale is used, thereby increasing the cost of the axle weighing scale.

  Secondly, when the center of gravity in the left-right direction is derived using the axle weight meter of Patent Document 1, it is necessary to separately obtain the tread interval (width between the left and right wheels) of the vehicle.

  Since the center of gravity of the vehicle generally exists in a three-dimensional space, three variables are required to determine its position. In this specification, the center of gravity of the vehicle in the vertical direction and the front-rear direction ( The measurement of the center of gravity position in the approach direction) is not the target, but only the measurement of the center of gravity position in the left-right direction of the vehicle (the vehicle width direction). Further, in the present specification, the target center-of-gravity position is referred to as a “width-direction center-of-gravity position” as necessary.

  The present invention has been made in view of such circumstances, and it is also an object of the present invention to provide an axle weight meter that can guide the wheel load of a vehicle by changing the mounting shape of a conventional axle weight meter. To do.

  Another object of the present invention is to provide a shaft weight meter that can guide the position of the center of gravity in the width direction of the vehicle by changing the mounting shape of the conventional shaft weight meter.

  In addition, the inventors of the present invention have noticed that the tire ground contact length for each wheel of the vehicle can be derived using the axle weight meter. If the tire pressure can be determined based on the tire contact length for each wheel of the vehicle, it is considered extremely useful for driving the vehicle.

  Therefore, the present invention also provides an axle weight meter that can determine whether the tire pressure is good or not based on the tire ground contact length for each vehicle wheel by changing the mounting shape of the conventional axle weight meter. Objective.

  By the way, the mounting base of the conventional axle weight meter is comprised by the rectangular plate member. Then, while the vehicle enters from one side of both ends of the platform and exits from the other side, the axle load of the vehicle is measured.

  On the other hand, the axle load meter of the present invention solves the above-described problem, and the axle load measuring platform can load both the left and right wheels of the vehicle, and the axle weight measuring surface used for measuring the axle weight of the vehicle axle. And a wheel weight measuring surface that can load only one of the left and right wheels of the vehicle and is used for measuring the wheel weight of only one of the left and right wheels of the vehicle (hereinafter referred to as such mounting). The stand is sometimes abbreviated as “new platform”, and the axle weight meter equipped with “new platform” is sometimes abbreviated as “new axle weight”).

  As described above, the new axle load scale according to the present invention has a time interval in which only one wheel of the vehicle acts on the new platform, and effectively utilizes this action to make the vehicle wheel in addition to the vehicle axle weight. The center of gravity and the center of gravity in the width direction can be obtained. Moreover, the new axle weight meter of this invention can also obtain | require a tire contact length.

  In addition, in the calculation of the vehicle wheel load and the center of gravity in the width direction and the tire ground contact length by the new axle weight meter, the hardware of the conventional axle weight control system can be used as it is.

The present invention has been devised for the first time based on such knowledge, and an aspect of the present invention is capable of loading both left and right wheels of a vehicle, and is used for measuring the axle load of the axle of the vehicle. A platform comprising: an axle load measurement surface; and a wheel load measurement surface capable of loading only one of the left and right wheels of the vehicle and used for measuring the wheel load of only the left and right wheels of the vehicle;
A plurality of load cells that support the table described above from below;
An output signal from the load cell when both the left and right wheels of the vehicle are placed on the axle load measurement surface, and the load cell when only one of the left and right wheels of the vehicle is placed on the wheel load measurement surface Calculation means for calculating wheel weights of both the left and right wheels of the vehicle based on an output signal from
An axle weight scale is provided.

  With this configuration, the axle load meter according to an embodiment of the present invention can give the function of measuring the wheel load of the vehicle to the conventional axle load meter only by changing the mounting shape of the conventional axle load meter. .

Further, according to one aspect of the present invention, both the left and right wheels of the vehicle can be loaded, and the axle load measuring surface used for measuring the axle weight of the axle of the vehicle, and only one of the left and right wheels of the vehicle can be loaded, A wheel load measuring surface for use in wheel load measurement of only one of the left and right wheels of the vehicle;
A plurality of load cells that support the table described above from below;
An output signal from the load cell when both the left and right wheels of the vehicle are placed on the axle load measurement surface, and the load cell when only one of the left and right wheels of the vehicle is placed on the wheel load measurement surface Calculation means for calculating the position of the center of gravity of the vehicle based on the output signal from
An axle weight scale is provided.

  With such a configuration, the axial weight meter according to an embodiment of the present invention can give the function of measuring the position of the center of gravity to the conventional axial weight meter only by changing the mounting shape of the conventional axial weight meter.

  In the axle load meter according to an aspect of the present invention, the calculation means may calculate the tread interval of the vehicle based on the output signal.

  With such a configuration, the axle load meter according to an embodiment of the present invention can also provide a function of measuring a tread interval to a conventional axle load meter.

  In the axle load meter according to a certain aspect of the present invention, the calculation means may calculate the position of the center of gravity in the width direction of the vehicle based on the wheel load of the wheel and the tread interval of the vehicle.

  With this configuration, the axle load meter according to an embodiment of the present invention can give a function of measuring the position of the center of gravity in the width direction of the vehicle to the conventional axle load meter.

Further, according to one aspect of the present invention, both the left and right wheels of the vehicle can be loaded, and the axle load measuring surface used for measuring the axle weight of the axle of the vehicle, and only one of the left and right wheels of the vehicle can be loaded, A wheel load measuring surface for use in wheel load measurement of only one of the left and right wheels of the vehicle;
A plurality of load cells that support the table described above from below;
The time waveform of the output signal from the load cell when both the left and right wheels of the vehicle are placed on the axle load measurement surface, and when only one of the left and right wheels of the vehicle is placed on the wheel load measurement surface Calculating means for calculating the tire ground contact length for each of the left and right wheels of the vehicle based on the time waveform of the output signal from the load cell,
An axle weight scale is provided.

  With this configuration, the axle load meter according to one aspect of the present invention measures the tire ground contact length for each of the left and right wheels of the vehicle by simply changing the mounting shape of the conventional axle load meter. The function to do can be given.

  Moreover, in the axle load meter of a certain form of this invention, the said calculating means may determine the quality of the tire air pressure for every said wheel based on the tire ground contact length for every said wheel.

  With this configuration, the axle load meter according to an embodiment of the present invention can give a function to determine whether the tire air pressure for each wheel is good or not to the conventional axle load meter using the tire ground contact length for each wheel.

  Further, in the axle weight meter according to an aspect of the present invention, the width of the vehicle loading portion of the aforementioned table constituting the wheel load measuring surface is set to be larger than the width of the vehicle loading portion of the preceding table constituting the axle weight measuring surface. May be narrowed.

  With this configuration, the stage of the axle load meter according to an embodiment of the present invention can generate a time interval in which only one wheel of the vehicle acts.

  Further, in the axle weight meter according to a certain aspect of the present invention, the vehicle loading portion of the preceding table constituting the wheel load measuring surface protrudes from the end of the vehicle loading portion of the preceding table constituting the axle weight measuring surface. You may let them.

  With this configuration, the axle load meter according to an embodiment of the present invention can appropriately include a mounting table having a wheel load measurement surface and an axle load measurement surface.

  Further, in the axle weight meter according to an aspect of the present invention, the vehicle loading portion of the aforementioned table constituting the wheel load measuring surface and the vehicle loading portion of the preceding table constituting the axle weight measuring surface are divided into rectangular plates. You may form by shaving a part of body.

  With this configuration, the axle load meter according to an embodiment of the present invention can appropriately include a mounting table having a wheel load measurement surface and an axle load measurement surface.

  Further, in the axial weight meter according to one aspect of the present invention, when the window is formed in the rectangular plate by cutting the rectangular plate, the rectangular plate adjacent to the window in the vehicle approach direction. Corresponds to the vehicle loading portion of the above-mentioned table constituting the axle load measurement surface, and the portion of the rectangular plate adjacent to the window portion in the direction orthogonal to the approach direction is the wheel load measurement surface It may correspond to the vehicle loading part of the above-mentioned stand which constitutes.

  With this configuration, the axle load meter according to an embodiment of the present invention can appropriately include a mounting table having a wheel load measurement surface and an axle load measurement surface.

  Further, in the axial weight meter according to one aspect of the present invention, when the notch is formed in the rectangular plate by cutting the rectangular plate, the rectangular plate adjacent to the notch in the vehicle approach direction. Corresponds to the vehicle loading portion of the above-mentioned table constituting the axle load measuring surface, and the portion of the rectangular plate body adjacent to the notch portion in the direction orthogonal to the approach direction is the wheel load measuring surface It may correspond to the vehicle loading part of the above-mentioned stand which constitutes.

  With this configuration, the axle load meter according to an embodiment of the present invention can appropriately include a mounting table having a wheel load measurement surface and an axle load measurement surface.

  According to the axle load meter of the present invention, the function of measuring the wheel load of the vehicle can be imparted to the conventional axle load meter simply by changing the mounting shape of the conventional axle load meter.

  Further, according to the axle load meter of the present invention, the function of measuring the center of gravity in the width direction of the vehicle can be imparted to the conventional axle load meter only by changing the mounting shape of the conventional axle load meter. .

  Furthermore, according to the axle weight meter of the present invention, it is possible to determine whether the tire pressure is good or bad based on the tire ground contact length for each wheel of the vehicle by simply changing the mounting shape of the conventional axle weight meter. It is also possible to provide a function for determining.

FIG. 1 is a view showing an example of a protruding platform used in the new axial weight meter according to the first embodiment of the present invention. FIG. 2 is a diagram used for explaining the dimensional design of the protruding platform of the new axle weight meter according to the first embodiment of the present invention. FIG. 3 is a diagram showing an example of a schematic structure of the new axle load meter according to the first embodiment of the present invention. FIG. 2A shows a plan view of the new axle weight scale, and FIG. 2B shows a side view of the new axle weight scale. FIG. 4 is a block diagram showing an example of the configuration of the control system of the new axle weight meter of FIG. FIG. 5 is a functional block diagram of the control device of the new axle weight meter of FIG. FIG. 6 is a diagram used for explaining the tire contact surface and the tire contact length of the vehicle. FIG. 7 is a schematic diagram used for explaining the vehicle wheel load deriving by the wheel load calculating unit of FIG. 5 and for explaining the vehicle wheel load deriving by the axle load calculating unit of FIG. FIG. 8 is a diagram used for explaining the derivation of the center of gravity position of the vehicle by the center of gravity position calculation unit of FIG. FIG. 9 is a diagram used for explaining the derivation of the center of gravity position of the vehicle by the center of gravity position calculation unit of FIG. FIG. 10 is a diagram showing an example of a schematic structure of a new axle load meter according to the second embodiment of the present invention. FIG. 2A shows a plan view of the new axle weight scale, and FIG. 2B shows a side view of the new axle weight scale. FIG. 11 is a functional block diagram of the control device of the new axle weight meter of FIG. FIG. 12 is a diagram used for explaining the tire contact length derivation for each of the left and right wheels of the vehicle by the tire air pressure calculation unit of FIG. FIG. 13 is a diagram showing an example of a schematic structure of a new axle scale according to a first modification of the present invention. FIG. 14 is a diagram showing an example of a schematic structure of a new axle scale according to a first modification of the present invention. FIG. 15 is a diagram showing an example of a schematic structure of a new axle scale according to a second modification of the present invention. FIG. 16 is a diagram showing an example of a schematic structure of a new axle scale according to a third modification of the present invention. FIG. 17 is a view showing an example of a schematic structure of a new axle scale according to a fourth modification of the present invention. FIG. 18 is a diagram showing an example of a schematic structure of a new axle weight meter according to a fifth modification of the present invention.

  Hereinafter, preferred first and second 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 first and second embodiments. That is, the following description of the first embodiment and the second embodiment merely exemplifies the features of the new axle load scale.

  Therefore, the present invention is not limited to a specific arithmetic expression in the formulation of the wheel load and the center of gravity in the width direction exemplified in the following first and second embodiments, and the tire exemplified in the second embodiment. It is not limited to a specific arithmetic expression in the contact length formulation.

  For example, a new platform of the new axle weight scale uses the allowable number of wheels “N” on the platform and the maximum number of axles “n” in all measurement targets, and “N = 2” shown in FIG. It is possible to classify into the “new stage”, the “N = n + 1 new stage” shown in FIG. 1B, and the “N = 2n−1 new stage” shown in FIG. 1C. it is conceivable that.

  Therefore, in the following first and second embodiments, the wheel load, total weight of the vehicle, A method for measuring axle load, center of gravity in the width direction, and tire pressure will be described. However, the concept of this measurement method is that the new axle load scale equipped with “the new N = n + 1 stage” shown in FIG. 1B also has “N = 2n−1” shown in FIG. The same can be applied to the new axle load scale equipped with the "new type platform" as it is.

  Moreover, there are various forms such as a projecting type, a windowed type, and a notch type in the new platform of the new axle load scale.

  Accordingly, in the following first and second embodiments, a method for measuring vehicle wheel load, total weight, axial load, center of gravity in the width direction, and tire air pressure using the protruding mount shown in FIG. The windowed platform will be described in the second modified example, and the notched platform will be described in the third modified example, the fourth modified example, and the fifth modified example.

  In this specification, the new platform is distinguished by using terms such as a protruding shape, a windowed shape, and a notch shape, but such terms are not intended to strictly define the form of the new platform, It is only used as a convenient means for intuitively understanding the form of the new stage. For example, the protruding platform of the first embodiment and the second embodiment can be regarded as a form in which one of the rectangular plates is cut into four when divided by two center lines. It can be used as a stand. However, in this specification, for convenience, a new type of platform in which a rectangular plate is cut into a rectangular shape and a concave shape is referred to as a notch type platform (for example, the third modification, the fourth modification, and the fifth modification). Refer to the modification).

  Further, in the present specification, for convenience of the following description, “new stage of N = 2” is abbreviated as “placement (N = 2)” and “new stage of N = n + 1”. There are cases where “mounting table (N = n + 1)” is abbreviated and “new loading table of N = 2n−1” is abbreviated as “mounting table (N = 2n−1)”. In addition, a plurality of types of new platforms may be collectively abbreviated as, for example, “mount (N = n + 1, N = 2n−1)”.

(First embodiment)
[Design of new stage]
Hereinafter, a method for designing the dimensions of the protruding platform 20 (N = 2) will be described with reference to the drawings.

  As shown in FIG. 1, the protruding platform 20 (N = 2, N = n + 1, N = 2n-1) carries both left and right wheels 11a, 11b, 12a, 12b of a vehicle 10 such as a four-wheel truck. It is possible to measure the axle load of the front axle 13 (hereinafter may be abbreviated as “first axis 13”) and the rear axle 14 (hereinafter abbreviated as “second axis 14”) of the vehicle 10. Only the left and right wheels (here, right wheels 11a, 12a) of the vehicle 10 and the left and right wheels (here, right wheels 11a, 12a) of the vehicle can be loaded. A wheel load measuring surface 22 used for measuring the wheel load.

  In such a protruding platform 20 (N = 2, N = n + 1, N = 2n−1), the rectangular main surface (front surface) having the points A, B, C, and G as vertices is the wheel load. A rectangular main surface (front surface) having points F, C, D, and E as vertices corresponds to the measurement surface 22, and the axial load measurement surface 21 corresponds to the measurement surface 22.

  Therefore, the requirements to be satisfied by the wheel load measuring surface 22 and the shaft load measuring surface 21 of the protruding platform 20 (N = 2) will be examined below regarding the approach of the vehicle 10. Such requirements can be organized as the following requirements (1) and (2).

    (1) During the measurement of the vehicle wheel load, the vehicle wheel immediately after that does not enter the wheel load measurement surface.

    (2) During the measurement of the vehicle axle load, the vehicle wheel immediately after that does not enter the wheel load measurement surface or the axle load measurement surface.

  Based on the above requirements (1) and (2), the dimensions of the protruding platform 20 (N = 2) can be designed.

  FIG. 2 is a diagram used for explaining the dimensional design of the protruding platform of the new axle weight meter according to the first embodiment of the present invention.

<Definition of symbols>
First, the meanings of symbols used in FIG. 2 are collectively defined.

t ₁ : When the tire of the right wheel 11 a of the first shaft 13 of the vehicle 10 is completely placed on the wheel load measuring surface 22 t ₃ : The tire of the left and right wheels 11 a and 11 b of the first shaft 13 of the vehicle 10 are shafts When fully loaded on the weight measurement surface 21 t ₄ : When the tires of the left and right wheels 11a and 11b of the first shaft 13 of the vehicle 10 begin to descend from the axle weight measurement surface 21 S: Tire contact length (in this example, tire) The ground contact length S is assumed to be the same for all wheels 11a, 11b, 12a, 12b)
α ₁ : Wheel load measurement allowance (however, α ₁ ≧ 0)
α ₂ : Shaft weight measurement allowance (however, α ₂ ≧ 0)
L ^* : Distance between adjacent axles, which is the smallest among all the vehicles to be measured (hereinafter referred to as “minimum distance between axes”)
L ₁ : Dimensions of the wheel weight measurement surface 22 in the approach direction of the vehicle 10 L ₂ : Dimensions of the axle load measurement surface 21 in the approach direction of the vehicle 10 β: Constraints based on the above requirements (1) and (2) Variable used (β = L ^* − (L ₁ + L ₂ ))
In FIG. 2, three white rectangles respectively represent the ground contact surfaces of both wheels 11 a and 11 b of the first shaft 13 (front axle), and with the passage of time (t ₁ → t ₃ → t ₄ ), It shows how the ground plane moves. Also, shaded rectangle represents the ground plane of the smallest axis distance L ^* min apart second shaft 14 (rear axle) shows the position of the ground surface at time t _4.

  From the above, as is apparent from FIG. 2, in the dimension design of the protruding mount 20 (N = 2), it is necessary to satisfy the constraint condition of the following expression (1) based on the above requirements (1) and (2). is there.

β = L ^* − (L ₁ + L ₂ ) ≧ 0 (1)
Then, it is understood that the optimum design of the protruding platform 20 (N = 2) is to derive the dimensions L ₁ and L ₂ that maximize α ₁ and α ₂ under the constraint condition of the above formula (1). it can.

Therefore, the dimensions L ₁ and L ₂ are obtained as follows based on the design guidelines.

As shown in FIG. 2, the dimensions L ₁ and L ₂ are expressed by the relationship of the following equation (2).

L ₁ = S + α ₁
L ₂ = S + α ₂ (2)
Substituting equation (2) into equation (1) yields equation (3) below.

α ₁ + α ₂ ≦ L ^* −2S (3)
When it is assumed that the vehicle 10 moves on the protruding platform 20 (N = 2) at a constant speed, when α ₁ and α ₂ are equal (α ₁ = α ₂ ), these are maximum values (α _MAX ). It seems reasonable to derive the dimensions L ₁ and L ₂ . Therefore, here, a method of determining the dimensions L ₁ and L ₂ when α ₁ and α ₂ are equal (α ₁ = α ₂ ) will be described.

First, the minimum inter-axis distance L ^* is expressed by the following equation (4) using the tire contact length S.

L ^* = λS (4)
By substituting equation (4) into equation (3), the following equation (5) is obtained, and since α ₁ = α ₂ , equation (6) is obtained.

α ₁ + α ₂ ≦ (λ−2) · S (5)
α ₁ (= α ₂ ) ≦ (λ−2) · S / 2 (6)
Therefore, α _MAX can be expressed as the following equation (7).

α _MAX = (λ−2) · S / 2 (7)
Thus, the dimensions L ₁ and L ₂ of the protruding mount 20 (N = 2) are given by the following equation (8).

L ₁ = L ₂ = S + α _MAX = S + (λ−2) · S / 2 = λ · S / 2 (8)
For example, when the minimum inter-axis distance L ^* is about three times the tire ground contact length S, λ in Equation (4) is λ = 3, so α _MAX = S / 2, L ₁ = L ₂ = S + α _It is estimated that _MAX = 3S / 2, L ₁ + L ₂ = 3S, β = 0 (that is, β is necessarily zero when the wheel load measurement allowance α ₁ and the axle load measurement allowance α ₂ are maximum). be able to.

In this way, the protruding platform 20 (N = 2) for which the dimensions L ₁ and L ₂ are determined can measure all wheel loads and axle loads of all the measurement target vehicles.

  The dimensions of the protruding platform 20 (N = n + 1) and the dimensions of the protruding platform 20 (N = 2n−1) can be similarly designed by taking the above method into consideration.

Therefore, although detailed description of these design methods is omitted here, α _MAX is greater in the projecting stage 20 (N = n + 1) than in the projecting stage 20 (N = 2). There is an advantage that can be increased. However, in this case, there is also a drawback that the protruding mount 20 (N = n + 1) becomes longer.

[Configuration of new axle load scale]
Hereinafter, the configuration of the new axle weight meter including the protruding platform 20 (N = 2) in which the dimensions L ₁ and L ₂ are determined will be described in detail with reference to the drawings.

  FIG. 3 is a diagram showing an example of a schematic structure of the new axle load scale according to the first embodiment of the present invention. A plan view of the new axle weight scale is shown in FIG. The side view of the new axle weight scale is shown in FIG.

  In this embodiment, for the sake of convenience, in FIG. 3, the full length direction of the vehicle 10 is illustrated as “front” and “rear” directions, and the width direction of the vehicle 10 is illustrated as “left” and “right” directions. Yes. Then, the vehicle 10 enters from “rear” of the protruding platform 20 (N = 2) and exits from “front” of the protruding platform 20 (N = 2). The configuration of 100 will be described. Therefore, in the following description, the approach direction of the vehicle 10 may be rephrased as the front-rear direction, and the width direction of the vehicle 10 may be rephrased as the left-right direction.

  As shown in FIG. 3, the new axle load scale 100 includes a protruding platform 20 (N = 2) on which a vehicle 10 such as a truck or a trailer can ride, a first load cell LC1, a second load cell LC2, a third A load cell LC3 and a fourth load cell LC4 (hereinafter, these load cells LC1, LC2, LC3, and LC4 may be collectively referred to as “load cells LC1 to LC4”).

  Here, as the vehicle 10, the front axle 13 with wheels 11a and 11b attached is one below the driver's seat, and the rear axle 14 with wheels 12a and 12b attached is one below the loading platform. A four-wheel truck in which a total of two axles 13 and 14 are arranged is illustrated.

  As shown in FIG. 3, the protruding platform 20 (N = 2) can load both the left and right wheels 11 a, 11 b, 12 a, 12 b of the vehicle 10, and the first shaft 13 and the second shaft 14 of the vehicle 10 can be loaded. Only the left and right wheels (here, the right wheels 11a and 12a) of the vehicle 10 and the left and right wheels of the vehicle 10 can be loaded, and only the left and right wheels of the vehicle (here, the right wheels) are used. A wheel load measuring surface 22 used for wheel load measurement of the wheels 11a, 12a).

  In this example, the entire left rear portion of the rectangular plate having the same shape (slightly smaller) as the pit portion 21A of the installation base 25 is scraped into a rectangular shape, so that the protruding platform 20 constituting the wheel load measuring surface 22 is formed. The (N = 2) vehicle loading portion (hereinafter abbreviated as “mounting vehicle loading portion”) is formed to be narrower than the loading vehicle loading portion constituting the axle load measuring surface 21. However, the formation of the platform vehicle loading portion that constitutes the axle load measurement surface 21 and the wheel load measurement surface 22 is not limited to this. Details of other examples will be described in the first modification.

  When the new axle load scale 100 is viewed in plan (FIG. 3A), a rectangular pit portion 21 </ b> A is formed on the surface of the installation base 25. As shown in FIG. 3, a protruding platform 20 (N = 2) and a lid member 26 are disposed in the pit portion 21 </ b> A.

  The lid member 26 is a member provided for the purpose of closing the pit space between the protruding platform 20 (N = 2) and the installation base 25. Therefore, instead of providing such a lid member 26, the pit portion of the installation base 25 may be formed along the shape of the protruding platform 20 (N = 2) in plan view (that is, the protruding shape). A slightly larger pit part than the mounting stage 20 (N = 2)). However, it is considered that the provision of the cover member 26 as in the present embodiment is advantageous from the viewpoint of the cost of the new axle load meter 100.

Further, as shown in FIG. 3A, the axial weight measuring surface 21 of the protruding platform 20 (N = 2) has a right end portion and a left end portion extending in the front-rear direction as short sides, and a front end portion extending in the left-right direction. and the rear end portion and the long side corresponds to the main surface (front surface) of the weighing platform vehicle loading part of the front and rear dimensions L ₂ and lateral dimension H ₂ rectangles.

On the other hand, the wheel load measuring surface 22 of the protruding platform 20 (N = 2) has a right end and a left end extending in the front-rear direction as long sides, a front end and a rear end extending in the left-right direction as short sides, corresponding to the principal surface (front surface) of the rectangular weighing platform vehicle loading part of the dimension L ₁ and lateral dimension H _1.

In this example, the dimensions L ₁ and L ₂ of the protruding platform 20 (N = 2) are determined in accordance with the design method of the protruding platform. Moreover, front and rear dimension L ₂ of the weighing platform vehicle loading portion constituting the axle load measuring surface 21 is substantially equal to the longitudinal dimension L ₁ of the platform vehicle loading portion constituting the wheel load measurement surface 22 (L ₂ = L ₁ ).

On the other hand, lateral dimension of H ₂ weighing platform vehicle loading portion constituting the axle load measuring surface 21 is set to be approximately 2 times the lateral dimension H ₁ of the weighing platform vehicle loading portion constituting the wheel load measurement surface 22 ( H ₂ = 2 · H ₁ ). In addition, the platform vehicle stacking unit that forms the wheel load measuring surface 22 protrudes from the end portion of the platform vehicle stacking unit that forms the axle load measuring surface 21 so that the both platform vehicle stacking units are integrally formed. Has been.

  However, the configuration of the protruding platform 20 (N = 2) described above is an example, and can be changed to various configurations.

  For example, the platform vehicle stacking portion constituting the axle load measuring surface 21 and the platform vehicle stacking portion constituting the wheel load measuring surface 22 are each constituted by separate plate members, and both plate members are appropriately fixed. You may form integrally using (welding, bolt fastening, etc.).

Further, the left-right dimension H ₁ of the mounting vehicle stacking portion constituting the wheel load measurement surface 22 may be slightly larger than half of the left-right dimension H ₂ of the mounting vehicle stacking portion constituting the axle load measurement surface 21. In some cases, only one of the left and right wheels of the vehicle 10 can be placed on the wheel load measuring surface 22. In this case, since the mounting vehicle stacking portion constituting the wheel load measuring surface 22 can be configured to be wide, the strength of the main mounting vehicle stacking portion can be improved.

Further, the shape of the platform vehicle stacking portion constituting the wheel load measuring surface 22 is not necessarily rectangular. For example, be determined based on a longitudinal dimension L ₁ of the weighing platform vehicle loading portion design method of the protruding type load platform, other shapes (e.g., polygonal such as chamfering the corners of the platform vehicle loading unit, etc. ).

  As shown in FIG. 3, each of the four load cells LC1 to LC4 is located on the installation base 25 below the protruding platform 20 (N = 2) at an appropriate corner of the protruding platform 20 (N = 2). It is arranged in.

Specifically, the first load cell LC1 and the third load cell LC3 are arranged at a constant interval (dimension a ₁ ; for example) on a straight line parallel to the rear end portion 20B in the vicinity of the rear end portion 20B of the protruding platform 20 (N = 2). , See FIG. 9), the second load cell LC2 and the fourth load cell LC4 are arranged on a straight line parallel to the front end portion 20F in the vicinity of the front end portion 20F of the protruding platform 20 (N = 2) ( Dimension a ₂ ; for example, see FIG. 9).

  On the other hand, the first load cell LC1 and the first load cell LC2 are arranged at a constant interval (dimension a; see, for example, FIG. 12) in the front-rear direction, and the third load cell LC3 and the fourth load cell LC4 In the vicinity of the right end portion 20R of (N = 2), they are arranged on a straight line parallel to the right end portion 20R with the same interval (dimension a; see, for example, FIG. 12) as the above-mentioned fixed interval.

  From the above, the back surface of the protruding platform 20 (N = 2) is supported from below by the load cells LC1 to LC4 on the installation base 25.

  As described above, the new axle weight meter 100 of the present embodiment is characterized in that the protruding platform 20 (N = 2) includes the axle weight measuring surface 21 and the wheel weight measuring surface 22. And in the new axle weight meter 100 of this embodiment, the function which measures the wheel weight of the vehicle 10 and the width direction gravity center position can be provided to the conventional axle weight meter by the said characteristic, The detail is mentioned later. To do.

[Configuration of control system of new axle load scale]
FIG. 4 is a block diagram showing an example of the configuration of the control system of the new axle weight meter of FIG. FIG. 5 is a functional block diagram of the control device for the new axle load meter of FIG.

  As shown in FIG. 4, the new axle scale 100 includes a control device 40, an operation device 41, and a display device 42.

  The control device 40 includes, for example, a plurality (here, four) amplifiers 43, a plurality (four here) low-pass filters 44, a multiplexer 45, and A / D conversion corresponding to each of the load cells LC1 to LC4. A calculator 46, an I / O circuit 47, a memory 48, and a calculator 49.

  The amplifier 43 has a function of amplifying a signal transmitted from the load cells LC1 to LC4 to a size capable of A / D conversion and sending it out.

  The low pass filter 44 has a function of passing only a low frequency as a signal.

  The multiplexer 45 has a function of selectively sending out a plurality of signals transmitted from each of the low-pass filters 44 based on a selection control signal command from the computing unit 49.

  The A / D converter 46 has a function of converting an analog signal from the multiplexer 45 into a digital signal.

  The I / O circuit 47 has a function of exchanging various signals and data among the A / D converter 46, the operation device 41, the display device 42, the memory 48, and the arithmetic unit 49.

  The memory 48 is composed of, for example, a PROM, a RAM, and the like, and has a function of storing a predetermined program, basic data, and the like for a long time, and temporarily storing various data, numerical values for calculation, and the like.

  The arithmetic unit 49 is constituted by a processing device such as a microprocessor (MPU), for example, and receives necessary signals via the I / O circuit 47 in accordance with instructions of a predetermined program stored in the memory 48, and necessary data. Is received from the memory 48 and has a function of executing an operation based on the received signal and data.

  The operation device 41 includes operation switches, numerical keys, and the like, 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 42 is composed of, for example, a liquid crystal display panel or the like, and displays measurement results and various data input / output screens.

[Processing of the control system of the new axle load scale]
In the control system of the new axle load meter 100, the output signals of the load cells LC <b> 1 to LC <b> 4 pass through the amplifier 43, the low-pass filter 44, the multiplexer 45, the A / D converter 46, and the I / O circuit 47 and the arithmetic unit 49. Sent to. The arithmetic unit 49 takes in a signal from the I / O circuit 47 according to a predetermined program stored in the memory 48 and reads various data stored in the memory 48.

  Thereby, the calculator 49 calculates various useful loading state quantities that can support the driving of the vehicle 10 based on these signals and data, and the calculation result is displayed on the display device 42.

  And in the new axle load scale 100 of this embodiment, in the control apparatus 40, when the predetermined program is executed by the calculator 49, as shown in FIG. 5, the wheels 11a, 11b, 12a, 12b of the vehicle 10 are controlled. A wheel load calculating unit 51 for calculating the wheel load, a center of gravity position calculating unit 52 for calculating the center of gravity of the vehicle 10, a total weight calculating unit 53 for calculating the total weight of the vehicle 10, and the axle weights of the axles 13 and 14 of the vehicle 10 are calculated. The respective functions of the axle load calculation unit 54 and the display signal generation unit 55 to be calculated are realized.

  Note that the control device 40 does not necessarily have to be composed of a single computing unit 49, and a plurality of computing units are arranged in a distributed manner so that they cooperate to control the operation of the new axle scale 100. It may be configured. For example, the function of the wheel load calculation unit 51, the function of the center of gravity position calculation unit 52, the function of the total weight calculation unit 53, and the function of the axle load calculation unit 54 are realized here using a single calculator 49. However, these functions may be realized by using a separate arithmetic unit (MPU).

  Therefore, hereinafter, the functions of the wheel load calculation unit 51, the center-of-gravity position calculation unit 52, the total weight calculation unit 53, and the shaft load calculation unit 54 of the new axle load meter 100 will be described in order. The function of the display signal generation unit 55 is known. Therefore, the function description of the display signal generation unit 55 is omitted here.

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

<Vehicle related>
X-axis (FIG. 8): Center line extending in the full length direction through the center position in the width direction of the vehicle 10 Y-axis (FIG. 8): An arbitrary point O on the X-axis in the horizontal plane including the X-axis As shown, straight line W _R1 : wheel weight of right wheel 11a of first shaft 13 of vehicle 10 W _L1 : wheel weight of left wheel 11b of first shaft 13 of vehicle 10 W _R2 : second of vehicle 10 Wheel weight W _L2 of the right wheel 12 a of the shaft 14: Wheel weight of the left wheel 12 b of the second shaft 14 of the vehicle 10 W ₁ : Axial weight of the first shaft 13 W ₂ : Axial weight of the first shaft 14 W: Vehicle 10 G G (FIG. 8): Center of gravity of vehicle 10 Y _G (FIG. 8): Eccentric amount of center of gravity position in the width direction of vehicle 10 in orthogonal coordinate system O-XY B ₁ (FIG. 8): First of vehicle 10 Tread interval B ₂ of the shaft 13 (FIG. 8): Tread interval of the second shaft 14 of the vehicle 10 S (FIG. 6): Tire contact length ( In this embodiment, it is assumed that the tire contact length S is the same for all the wheels 11a, 11b, 12a, and 12b).

<Load cell output and placement-related>
P ₁ : Output of first load cell LC 1 P ₂ : Output of second load cell LC 2 P ₃ : Output of third load cell LC 3 P ₄ : Output of fourth load cell LC 4 P: Sum of outputs of all load cells LC 1 to LC 4 (P = P ₁ + P ₂ + P ₃ + P ₄ )
a ₁ (FIG. 9): Center-to-center distance between first load cell LC1 and third load cell LC3 a ₂ (FIG. 9): Center-to-center distance between second load cell LC2 and fourth load cell LC4

b (FIG. 9): Distance from the straight line connecting the third load cell LC3 and the fourth load cell LC4 to the operating point of the wheel load W _R1 of the first shaft 13 Of the above symbols, the distances a ₁ and a ₂ are , Known values (fixed values depending on the arrangement of the load cells LC1 to LC4), and these values are stored in the memory 48 in advance.

<Protruding platform related>
x-axis (FIGS. 7 and 9): center line extending in the front-rear direction through the center position in the width direction of the axial load measuring surface 21 y-axis (FIGS. 7 and 9): of the protruding platform 20 (n = 2) Center line extending in the width direction through the center position in the front-rear direction o (Small O; FIGS. 7 and 9): intersection of the x-axis and the y-axis

<Load cell output waveform>
As shown in FIG. 6, in the tire of the right wheel 11a (left wheel 11b) of the first shaft 13 (the same applies to the second shaft 14) of the vehicle 10, the installation base 25 (lid member 26) and the wheel load measuring surface 22 ( A tire contact surface 30 is formed with the axle load measuring surface 21), and the tire has a tire contact length S. Therefore, when the vehicle 10 gets on the protruding platform 20 (N = 2), a plurality of break points appear in the output waveform of the output P of the load cells LC1 to LC4 (see, for example, FIG. 7B). Times t ₀ , t ₁ , t ₂ , t ₃ , t ₄ and t ₅ corresponding to the break points of these output waveforms can be defined as follows.

t ₀ : When the tire of the right wheel 11 a of the first shaft 13 starts to enter the wheel load measuring surface 22 t ₁ : When the tire of the right wheel 11 a of the first shaft 13 is completely placed on the wheel load measuring surface 22 t ₂ : When the tire of the left wheel 11b of the first shaft 13 starts to get on the axle load measuring surface 21 t ₃ : When the tire of the left wheel 11b of the first shaft 13 is completely placed on the axle weight measuring surface 21 t ₄ : No. left and right wheels 11a monoaxial 13, t when 11b tire starts to descend from the axle load measurement surface 21 _5: when the left and right wheels 11a of the first shaft 13, 11b tire got off completely from the axle load measuring surface 21

[Function of wheel load calculation unit]
Hereinafter, the function of the wheel load calculating unit 51 of the new axle load scale 100 will be described.

  FIG. 7 is a schematic diagram used for explaining the vehicle wheel load deriving by the wheel load calculating unit of FIG. 5 and for explaining the vehicle wheel load deriving by the axle load calculating unit of FIG.

  Here, since the purpose is to understand these derivation methods, the illustration of the configuration of the new axle load scale 100 not directly related to the derivation method is omitted or simplified for convenience. For example, in FIG. 7, the installation base 25 (see FIG. 1) is not shown.

  In addition, the illustration of the configuration of the vehicle 10 is simplified as appropriate, for example, the first shaft 13 is abbreviated by its tire center line.

In order to guide the wheel loads W _R1 and W _L1 of the first shaft 13 of the vehicle 10, the output waveforms (time waveforms) of the load cells LC1 to LC4 when the vehicle 10 moves on the protruding platform 20 (N = 2). Need to know the meaning of

  First, the output waveforms of the load cells LC1 to LC4 will be described.

FIG. 7B is a diagram showing output waveforms (time waveforms) of the load cells LC1 to LC4 when both wheels of the first shaft of the vehicle of FIG. Specifically, the x-axis of the orthogonal coordinate system o-xy (here, the position of the first axis 13 (tire centerline position)) is taken on the horizontal axis, and P (x which is the sum of the outputs of all the load cells LC1 to LC4. ) (= P ₁ (x) + P ₂ (x) + P ₃ (x) + P ₄ (x)) is plotted on the vertical axis, and the relationship between the two is shown.

  In FIG. 7, the first axis 13 of the vehicle 10 is shown in association with the position of the x-axis (however, only the tire centerline of the first axis 13 is shown) in order to facilitate understanding of the meaning of the output waveform. A state in which the right wheel 11a is approaching the protruding mount 20 (N = 2) is also shown.

  The output waveform of P (x) in FIG. 7B can be understood as follows.

As shown in FIG. 7A, when the tire of the right wheel 11a of the first shaft 13 starts to get on the wheel load measuring surface 22 (time t ₀ ), the output waveform of P (x) starts to rise, When the tire of the right wheel 11a of the shaft 13 is completely placed on the wheel load measuring surface 22 (time t ₁ ), the value of the output waveform is constant. In this case, the output value of P (x) corresponds to the wheel load W _R1 . At this time, a tire ground contact surface 30 is generated between the tire of the right wheel 11a of the first shaft 13 of the vehicle 10 and the protruding mount 20 (N = 2). However, the wheel weight of the right wheel 11a is in contact with the tire. When it is assumed that the ground 30 acts as an evenly distributed load, the rising profile of the output waveform is almost a polygonal line as shown in FIG. The distance between the position of the x-axis corresponding to the time t _0, the position of the x-axis corresponding to the time t ₁ is equal to the tire contact length S.

Next, when the tire of the left wheel 11b of the first shaft 13 starts to enter the axle load measuring surface 21 (time t ₂ ), the output waveform of P (x) starts to rise again, and the right wheel 11a of the first shaft 13 starts to rise again. When the tire is completely placed on the axle load measurement surface 21 (time t ₃ ), the value of the output waveform is constant. In this case, the output value of P (x) corresponds to the axial load W ₁ (= W _R1 + W _L1 ). At this time, although the tire contact surface 30 between the tire of the left wheel 11b and the protruding type mounting base 20 (N = 2) of the first axis 13 of the vehicle 10 occurs, the wheel load _{W L1} of the left wheel 11b When it is assumed that the tire ground contact surface 30 acts as an evenly distributed load, the rising profile of the output waveform is almost a polygonal line as shown in FIG. The distance between the position of the x axis corresponding to time t _2, the the position of the x-axis corresponding to the time t ₃ is equal to the tire contact length S.

As described above, P (t) in the time interval [t ₁ , t ₂ ] is output from the load cells LC1 to LC4 when only the right wheel 11a of the first shaft 13 of the vehicle 10 is placed on the wheel load measurement surface 22. corresponds to the sum of the signal (load signal), this value corresponds to the wheel load W _R1.

Therefore, the wheel load W _R1 can be obtained by the following equation (9).

Wheel load W _R1 = P (t) (9)
However, in Formula (9), t is the time (t ₁ <t <t ₂ ) in the time interval [t ₁ , t ₂ ].

Further, P (t) in the time interval [t ₃ , t ₄ ] is an output signal from the load cells LC1 to LC4 when both wheels 11a and 11b of the first shaft 13 of the vehicle 10 are placed on the axle load measuring surface 21. This value corresponds to the sum of (load signals), and this value corresponds to the axial load W ₁ (= W _L1 + W _R1 ) of the first shaft 13.

Thus, the wheel load _{W L1} can be determined by the following equation (10).

Wheel load W _L1 = P (t) −W _R1 = W ₁ −W _R1 (10)
However, in Formula (10), t is the time (t ₃ <t <t ₄ ) in the time interval [t ₃ , t ₄ ].

Note that the method for deriving the wheel loads W _R2 and W _L2 of the second shaft 14 of the vehicle 10 can be easily understood by considering the method for deriving the wheel loads W _R1 and W _L1 . Therefore, the description of the method for deriving the wheel loads W _R2 and W _L2 of the second shaft 14 of the vehicle 10 is omitted here.

As described above, in the new axle weight meter 100 of the present embodiment, the wheel weight calculation unit 51 uses the above formulas (9) and (10) to set the wheel weights W _R1 and W _L1 of the first shaft 13 of the vehicle 10. Can be calculated. Further, the wheel load calculating unit 51 can also calculate the wheel loads W _R2 and W _L2 of the second shaft 14 of the vehicle 10 in the same manner as the wheel load calculation of the first shaft 13.

[Function of axle load calculation unit]
Hereinafter, the function of the axle load calculator 54 of the new axle load meter 100 will be described.

As described above, P (t) in the time interval [t ₃ , t ₄ ] is obtained from the load cells LC1 to LC4 when both wheels 11a and 11b of the first shaft 13 of the vehicle 10 are placed on the axle load measurement surface 21. This value corresponds to the sum of output signals (load signals), and this value corresponds to the axial load W ₁ of the first shaft 13.

Therefore, the axial weight W ₁ of the first shaft 13 of the vehicle 10 can be obtained by the following equation (11).

Axle load W ₁ = P (t) (11)
However, in Formula (11), t is the time (t ₃ <t <t ₄ ) in the time interval [t ₃ , t ₄ ].

Note that the derivation of the axle weight W ₂ of the second shaft 14 of the vehicle 10, can be readily understood by reference to the derivation of the shaft heavy W _1. Therefore, description of the method of deriving the axial load of the second shaft 14 of the vehicle 10 is omitted here.

As described above, in the new axle load meter 100 of the present embodiment, the axle load calculator 54 can calculate the axle load W ₁ of the first shaft 13 of the vehicle 10 using the equation (11). Further, the axle load calculator 54 can also calculate the axle load W ₂ of the second shaft 14 of the vehicle 10 in the same manner as the axle load calculation of the first shaft 13.

[Function of total weight calculation unit]
Hereinafter, the function of the total weight calculation unit 53 of the new axle load scale 100 will be described.

The total weight W of the vehicle 10 corresponds to the sum of the axial weight W ₁ of the first shaft 13 of the vehicle 10 and the axial weight W ₂ of the second shaft 14 of the vehicle 10.

As described above, in the new axle weight meter 100 of the present embodiment, the total weight calculation unit 53 uses the axle weight W ₁ of the first shaft 13 of the vehicle 10 and the axle weight W ₂ of the second shaft 14 of the vehicle 10. Thus, the total weight W of the vehicle 10 can be calculated.

[Function of center of gravity position calculation unit]
Hereinafter, the function of the center-of-gravity position calculation unit 52 of the new axle scale 100 will be described.

First, the center of gravity position of the vehicle 10 (the eccentric amount Y _{G in} the width direction of the vehicle 10) will be described with reference to the drawings.

  FIG. 8 is a diagram used for explaining the derivation of the center of gravity position of the vehicle by the center of gravity position calculation unit of FIG. However, in FIG. 8, only the left and right wheels 11a, 11b, 12a, and 12b of the vehicle 10 are illustrated.

  As shown in FIG. 8, in the new axle scale 100 of the present embodiment, in the formulation of the position of the center of gravity G of the vehicle 10, along the vehicle center line that passes through the center position in the width direction of the vehicle 10 and extends in the full length direction. An X axis is defined, and a Y axis is provided along a straight line that passes through an arbitrary point O on the X axis and is orthogonal to the X axis in a horizontal plane including the X axis.

That is, the new axial weight meter 100 of the present embodiment is characterized in that the center of gravity position (Y _G ) in the width direction corresponding to the position of the center of gravity G of the vehicle is obtained with reference to the orthogonal coordinate system O-XY. Thus, the position of the center of gravity G can be simply formulated as follows by considering the orthogonal coordinate system O-XY without depending on the orthogonal coordinate system o-xy of FIG.

<Derivation method of Y _G >
As shown in FIG. 8, Y _G represents the amount of eccentricity of the position of the center of gravity G in the width direction of the vehicle 10 in the orthogonal coordinate system O-XY.

Here, Y _G can be expressed by the following equation (12) from the equation of moment balance.

Y _G = {B ₁ (W _L1 −W _R1 ) + B ₂ (W _L2 −W _R2 )} / 2 (W _R1 + W _L1 + W _R2 + W _L2 )
(12)
However, the sign of _{Y G} of the formula (12) is left as viewed from the approach direction of the vehicle 10 (the first quadrant of the orthogonal coordinate system O-XY and second quadrants) plus (+), right (rectangular coordinate system O -XY (3rd quadrant and 4th quadrant) are set to minus (-).

In equation (12), if the tread interval B ₁ of the first shaft 13 of the vehicle 10 and the tread interval B ₂ of the second shaft 14 of the vehicle 10 can be obtained, Y _G can be calculated based on the equation. .

Therefore, the tread interval B ₁ of the first shaft 13 of the vehicle 10 and the tread interval B ₂ of the second shaft 14 of the vehicle 10 are obtained as follows.

<How to find the tread interval>
Hereinafter, the method of determining the tread spacing B _1, is described with reference to FIG.

  In FIG. 9A, the balance of moments about a straight line connecting the third load cell LC3 and the fourth load cell LC4 is considered. Then, due to the balance of moments, the following expression (13) is established, and as a result, the relational expression of expression (14) is obtained.

b · W _R1 −a ₁ · P ₁ (t) −a ₂ · P ₂ (t) = 0 (13)
b = 1 / W _R1 · (a ₁ · P ₁ (t) + a ₂ · P ₂ (t)) (14)
However, in Formula (13) and Formula (14), t is the time (t ₁ <t <t ₂ ) in the time interval [t ₁ , t ₂ ].

  In FIG. 9B, the balance of moments about a straight line connecting the third load cell LC3 and the fourth load cell LC4 is considered. Then, the following equation (15) is established due to the balance of moments, and as a result, the relational equation of equation (16) is obtained.

b · W _R1 + (b + B ₁ ) · W _L1 −a ₁ · P ₁ (t) −a ₂ · P ₂ (t) = 0
... (15)
B ₁ = 1 / W _L1 · (a ₁ · P ₁ (t) + a ₂ · P ₂ (t) −b · W _R1 )
... (16)
However, in Formula (15) and Formula (16), t is the time (t ₃ <t <t ₄ ) in the time interval [t ₃ , t ₄ ].

By the above, by using equation (14), can be derived the distance b to the point of action of the wheel load W _R of the first shaft 13 from the straight line connecting the third load cell LC3 and a fourth load cell LC4, this distance the b by substituting the equation (16) can calculate the tread distance _{B 1} of the first axis 13 of the vehicle 10.

Note that the derivation of the tread spacing B ₂ of the second shaft 14 of the vehicle 10, can be readily understood by reference to the derivation of the tread spacing B _1. Therefore, the description of derivation of the tread spacing B ₂ of the second shaft 14 of the vehicle 10 will be omitted.

In this manner, the new axle load scale 100 of the present embodiment can calculate the tread intervals B ₁ and B ₂ . As a result, the center-of-gravity position computing unit 52 of the new axle weight detecting 100, tread spacing _{B 1} of the first axis 13 of the vehicle 10, the tread distance _{B 2} of the second shaft 14, the wheel load _{W R1, W L1, W R2} , based on the acquisition of W _L2, it is possible to calculate the _{Y G} of the center of gravity G of the vehicle 10 by using the equation (12).

(Second Embodiment)
[Configuration of new axle load scale]
FIG. 10 is a diagram showing an example of a schematic structure of a new axle weight meter according to the second embodiment of the present invention. A plan view of the new axle weight scale is shown in FIG. The side view of the new axle weight scale is shown in FIG.

  In this embodiment, for the sake of convenience, in FIG. 10, the full length direction of the vehicle 10 is illustrated as “front” and “rear” directions, and the width direction of the vehicle 10 is illustrated as “left” and “right” directions. Yes. Then, the vehicle 10 enters from “rear” of the protruding platform 20 (N = 2) and exits from “front” of the protruding platform 20 (N = 2). The configuration of 200 will be described. Therefore, in the following description, the approach direction of the vehicle 10 may be rephrased as the front-rear direction, and the width direction of the vehicle 10 may be rephrased as the left-right direction.

  FIG. 11 is a functional block diagram of the control device for the new axle load meter of FIG.

  In the new axle load scale 200 of the present embodiment, a predetermined program is executed by the calculator 49 (see FIG. 4) in the control device 40A, so that the wheels 11a, 11b, and 12a of the vehicle 10 are shown in FIG. , 12b, a center of gravity position calculator 52 for calculating the center of gravity of the vehicle 10, a total weight calculator 53 for calculating the total weight of the vehicle 10, and the axles 13 and 14 of the vehicle 10. In addition to the functions of the axle load calculator 54 and the display signal generator 55 that calculate the axle load, the tire pressure calculator 56 that predicts the tire air pressure of the left and right wheels 11a, 11b, 12a, and 12b of the vehicle 10 Functions are also realized.

  That is, the new axle load scale 200 of the present embodiment realizes this function in that the function of the tire air pressure calculation unit 56 can be realized by executing a predetermined program by the calculator 49 in the control device 40A. Although not distinguished from the new axle weight meter 100 (see FIG. 1) of the first embodiment, the components of the new axle weight meter 100 can be used as they are on the hardware.

  Therefore, here, the same reference numerals are given to the components of the new axle load meter 200 of the present embodiment that are the same as or equivalent to the components of the new axle load meter 100 of the first embodiment, and the configuration common to both The detailed description of is omitted.

  The control device 40A does not necessarily need to be composed of a single computing unit 49 (see FIG. 4), and a plurality of computing units are arranged in a distributed manner, and these cooperate to control the operation of the new axle load scale. It may be configured to. For example, the function of the tire pressure calculation unit 56 described below, the function of the wheel load calculation unit 51 described in the first embodiment, the function of the center of gravity position calculation unit 52, the function of the total weight calculation unit 53, and the axle load calculation unit Each of the 54 functions has its own value. Therefore, only the function of the tire air pressure calculation unit 56 is realized by using an arithmetic unit specialized for realizing the function of the tire air pressure calculation unit 56 so that the tire air pressure of the wheels 11a, 11b, 12a, 12b of the vehicle 10 can be predicted. A new axle load scale may be constructed.

The functions of the wheel load calculator 51, the center of gravity position calculator 52, the total weight calculator 53, and the axle load calculator 54 are the same as those described in the first embodiment. Further, the meanings of symbols used in the following description and related drawings are also described in the first embodiment except for the following tire contact lengths S _R1 , S _L1 , S _R2 , S _L2 and P ₁₃ (t). The contents are the same. Further, the function of the display signal generation unit 55 is known. Therefore, detailed description thereof will be omitted here.

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

S _R1 : Tire contact length of the right wheel 11a of the first shaft 13 of the vehicle 10 S _L1 : Tire contact length of the left wheel 11b of the first shaft 13 of the vehicle 10 S _R2 : Right wheel 12a of the second shaft 14 of the vehicle 10 Tire contact length S _L2 : tire contact length of the left wheel 12b of the second shaft 14 of the vehicle 10 P ₁₃ : sum of outputs of the first load cell LC1 and the third load cell LC3 (P ₁₃ = P ₁ + P ₃ )
a (FIG. 12): Distance between the centers of the first load cell LC1 (third load cell LC3) and the second load cell LC2 (fourth load cell LC4) Δa (FIG. 12): after the protruding platform 20 (N = 2) Distance between the end 20B and the center of the first load cell LC1 (third load cell LC3) Of the above symbols, the distances a and Δa are known values (the shape of the protruding platform 20 (N = 2) and the load cell). (Fixed values depending on the arrangement of LC1 to LC4), and these values are stored in the memory 48 in advance.

[Function of tire pressure calculation unit]
Hereinafter, the function of the tire air pressure calculation unit 56 of the new axle scale 200 will be described.

The tire ground contact lengths S _R1 , S _L1 , S _R2 , S _L2 of the left and right wheels 11a, 11b, 12a, 12b of the vehicle 10 depend on the corresponding air pressure and wheel load W _R1 , W _L1 , W _R2 , W _L2. Change. Therefore, if such tire ground contact lengths S _R1 , S _L1 , S _R2 , S _L2 and wheel weights W _R1 , W _L1 , W _R2 , W _L2 can be calculated, wheels 11a, 11b are based on these values. , 12a, 12b should be able to predict the excess or deficiency of the tire pressure.

That is, when the tire pressure is low, or when the wheel loads W _R1 , W _L1 , W _R2 , and W _L2 are large, the tire contact lengths S _R1 , S _L1 , S _R2 , and S _L2 become long. Conversely, when the air pressure is high, or when the wheel loads W _R1 , W _L1 , W _R2 , and W _L2 are small, the tire contact lengths S _R1 , S _L1 , S _R2 , and S _L2 are shortened. If the vehicle 10 travels in a state where the tire air pressure is low, a tire trouble (for example, a tire burst during traveling) of the vehicle 10 occurs. Therefore, knowing the tire air pressure of the vehicle 10 is important for driving the vehicle 10.

The method for deriving the vehicle wheel loads W _R1 , W _L1 , W _R2 , and W _L2 by the new axle weight meter 200 can be understood by referring to the contents described in the first embodiment.

Therefore, hereinafter, a method of calculating the tire contact lengths S _R1 , S _L1 , S _R2 , and S _L2 for each of the left and right wheels 11a, 11b, 12a, and 12b of the vehicle 10 will be described.

<Derivation method of vehicle tire ground contact length>
FIG. 12 is a diagram used for explaining the tire contact length derivation for each of the left and right wheels of the vehicle by the tire air pressure calculation unit of FIG. 11.

  Here, since the purpose is to understand these derivation methods, the illustration of the configuration of the new axle load scale 200 not directly related to the derivation method is omitted or simplified for convenience. For example, in FIG. 12, the installation base 25 (see FIG. 1) is not shown.

  In addition, the illustration of the configuration of the vehicle 10 is simplified as appropriate, such that the first shaft 13 is abbreviated with its tire centerline, and the tires of both wheels 11a and 11b of the first shaft 13 are abbreviated with thick dotted lines. .

In order to derive the tire ground contact lengths S _R1 and S _L1 for each of the wheels 11a and 11b of the first shaft 13, output waveforms of the load cells LC1 to LC4 when the vehicle 10 moves on the protruding platform 20 (N = 2). It is necessary to know the meaning of (time waveform).

  Therefore, the output waveforms of the load cells LC1 to LC4 will be described below.

  FIGS. 12B and 12C are diagrams showing output waveforms (time waveforms) of the load cells LC <b> 1 to LC <b> 4 when both wheels of the first shaft of the vehicle of FIG. 1 get on the protruding platform. is there.

Specifically, in FIG. 12B, the horizontal axis represents the position of the first shaft 13 (tire centerline position), and P (x) (= P ₁ (= P ₁ ( x) + P ₂ (x) + P ₃ (x) + P ₄ (x)) is plotted on the vertical axis to show the relationship between the two.

In FIG. 12C, the position of the first shaft 13 is taken on the horizontal axis (tire centerline position), and P ₁₃ (x) (= P ₁ ), which is the sum of the outputs of the first load cell LC1 and the third load cell LC3. The output waveform of (x) + P ₃ (x)) is plotted on the vertical axis, and the relationship between the two is illustrated.

In the orthogonal coordinate systems of FIGS. 12B and 12C, unlike the orthogonal coordinate system o-xy of FIG. 7, the tire of the right wheel 11a of the first shaft 13 of the vehicle 10 is the wheel load measurement surface. The position of the first axis 13 corresponding to the time when the boarding starts (time t ₀ ) 22 is set as the x-axis origin o ′. Further, in FIG. 12A, in order to facilitate understanding of the meaning of the output waveform, both wheels 11a and 11b of the first shaft 13 of the vehicle 10 project in association with the position of the x-axis. A state in which the stage 20 (N = 2) is approached is also shown.

  As can be easily understood from FIG. 12, when the vehicle 10 gets into the new axle weight scale 200, the order in which the wheels 11 a and 11 b of the first shaft 13 of the vehicle 10 enter is the right wheel 11 a and the first shaft of the first shaft 13. The order of 13 left wheels 11b. Therefore, the output waveforms (time waveforms) of the load cells LC1 to LC4 when both the wheels 11a and 11b of the first shaft 13 of the vehicle 10 get on the protruding mount 20 (N = 2) are as shown in FIG. expressed.

Note that the profile of the output waveform of P (x) (= P ₁ (x) + P ₂ (x) + P ₃ (x) + P ₄ (x)) in FIG. 12B is the P in the first embodiment. It can be easily understood by referring to the explanation of the profile of the output waveform (x). Therefore, detailed description of the output waveform profile of P (x) (= P ₁ (x) + P ₂ (x) + P ₃ (x) + P ₄ (x)) in FIG. 12B is omitted here. To do.

On the other hand, the output waveform (time waveform) of P ₁₃ (x) (= P ₁ (x) + P ₃ (x)) in FIG. 12C is a moment around a straight line connecting the second load cell LC2 and the fourth load cell LC4. Based on the balance formula, it can be understood as follows.

As shown in FIG. 12A, when the tire of the right wheel 11a of the first shaft 13 starts to get on the wheel load measuring surface 22 (time t ₀ ), the output waveform of P ₁₃ (x) starts to rise, When the tire of the right wheel 11a of the single shaft 13 is completely placed on the mount protrusion 22 (time t ₁ ; x-axis = x ₁ ), the value of the output waveform becomes the maximum. In FIG. 12C, the position (vertex) of the output waveform of P ₁₃ (x) at time t ₁ is set as the coordinate A, and the output value of P ₁₃ (x) at the coordinate A is set as “W ^* ”. Further, the position of the x axis corresponding to the time t ₁ is set as the coordinate B.

Thereafter, as shown in FIG. 12C, the output value of P ₁₃ (x) starts to decrease linearly.

_{Here, P} 13 output value (x) (contribution _{K R1} of _P 13 to (x) of the wheel load _{W R1),} the first shaft 13 on the x-axis of the third load cell LC3 (first load cell LC1) (when x-axis = _{x 2)} when it reaches, equal to the wheel load _{W R1.} In FIG. 12C, the position of the output waveform of P ₁₃ (x) at this time is set as a coordinate D, and the position of the x axis at this time is set as a coordinate E.

The contribution K _R1 becomes zero when the first axis 13 reaches the x axis of the fourth load cell LC4 (second load cell LC2) (when x axis = x ₄ ). In FIG. 12C, the position of the output waveform of P ₁₃ (x) at this time (that is, the position of the x-axis at this time) is the coordinate C.

Next, as shown in FIG. 12A, when the tire of the left wheel 11b of the first shaft 13 starts to get on the axle load measurement surface 21 (time t ₂ ; x axis = x ₃ ), P ₁₃ (x) The output waveform starts to rise again, and when the tire of the right wheel 11a of the first shaft 13 is completely placed on the axle load measuring surface 21 (time t ₃ ), the value of the output waveform becomes maximum. In FIG. 12C, the position (break point) of the output waveform of P ₁₃ (x) at time t ₂ is set as the coordinate F, and the output value of P ₁₃ (x) at the coordinate F is set as “W ^** ”. Yes. Further, the position of the x axis corresponding to the time t ₂ is set as the coordinate G.

Thereafter, as shown in FIG. 12 (c), the output value of P ₁₃ (x) starts to decrease linearly again.

Here, the contribution K _L1 of the wheel load W _L1 to P ₁₃ (x) (see the dotted line in FIG. 12C) is such that the first axis 13 is on the x axis of the fourth load cell LC4 (second load cell LC2). (when x-axis = x ₄₎ when it reaches, becomes zero. Also, the output value of P ₁₃ (x) (see the solid line in FIG. 12C) is also when the first axis 13 reaches the x axis of the fourth load cell LC4 (second load cell LC2) (x axis = when x _4), it becomes zero. In FIG. 12C, the position of the output waveform of P ₁₃ (x) at this time (that is, the position of the x-axis at this time) is the coordinate C.

By using the output waveform (time waveform) of P ₁₃ (x) described above, the tire ground contact lengths S _R1 and S _L1 of the two wheels 11a and 11b of the first shaft 13 of the vehicle 10 are the geometric shapes shown in FIG. The following can be derived based on the scientific relationship.

First, by using the fact that a right triangle having vertices at coordinates A, B, and C in FIG. 12C is similar to a right triangle having vertices at coordinates D, E, and C in FIG. The contact length S _R1 can be formulated.

According to the coordinate system of FIG. 12B, x ₁ = S _R1 and x ₄ = S _R1 / 2 + Δa + a. Therefore, the distance between the position (x ₁ ) on the x-axis corresponding to the coordinates A and B and the position (x ₄ ) on the x-axis corresponding to the coordinate C is a dimension (Δa + a−S _R1 / 2). It can be expressed as. The distance between the position (x ₂ ) on the x-axis corresponding to the coordinates D and E and the position (x ₄ ) on the x-axis corresponding to the coordinate C can be expressed by a dimension a.

Then, the following relational expression (17) is obtained by using the similarity relation between the above right triangles, and when the expression (17) is modified, the tire contact length _SR1 is expressed as the following expression (18). Can do.

W ^* / (Δa + a−S _R1 / 2) = W _R1 / a (17)
S _R1 = (2-W ^* / W _R1 ) · a + 2Δa (18)
Next, using the fact that the right triangle having the vertices of coordinates D, E, and C in FIG. 12C is similar to the right triangle having the vertices of coordinates F, G, and C in FIG. The contact length S _L1 can be formulated as follows.

According to the coordinate system of FIG. 12B, x ₃ = Δa + a / 2 + (S _R1 −S _L1 ) / 2 and x ₄ = S _R1 / 2 + Δa + a can be obtained. Therefore, the distance between the position (x ₃ ) on the x-axis corresponding to the coordinates F and G and the position (x ₄ ) on the x-axis corresponding to the coordinate C is the dimension (a / 2 + S _L1 / 2) It can be expressed as. The distance between the position (x ₂ ) on the x-axis corresponding to the coordinates D and E and the position (x ₄ ) on the x-axis corresponding to the coordinate C can be expressed by a dimension a.

Then, the following relational expression (19) is obtained by using the similarity relation between the above right triangles, and when the expression (19) is transformed, the tire contact length S _L1 is expressed as the following expression (20). Can do.

W _R1 / a = W ^** / (a / 2 + S _L1 / 2) (19)
S _L1 = (2W ^** / W _R1 −1) · a (20)
The method for deriving the tire contact lengths S _R2 and S _L2 for the wheels 12a and 12b of the second shaft 14 can be easily understood by taking into account the method for deriving the tire contact lengths S _R1 and S _L1 . Therefore, description of the method for deriving the tire contact lengths S _R2 and S _L2 is omitted here.

In this way, the tire ground contact lengths S _R1 and S _L1 for the respective left and right wheels 11a and 11b of the vehicle 10 can be obtained using the above formulas (18) and (20), respectively. Further, the tire ground contact lengths S _R2 and S _{L2 for} the respective left and right wheels 12a and 12b of the vehicle 10 can also be obtained in the same manner as the tire ground contact lengths S _R1 and S _L1 .

As described above, in the new axle weight meter 200 of the present embodiment, the tire air pressure calculation unit 56 calculates the tire ground contact lengths S _R1 , S _L1 , S _R2 , S _L2 using the output waveforms (time waveforms) of the load cells LC1 to LC4. While being able to calculate, as described in the first embodiment, the wheel load calculation unit 51 can calculate the wheel loads W _R1 , W _L1 , W _R2 , and W _L2 of the vehicle 10.

As a result, the tire air pressure calculation unit 56 of the new axle load meter 100 is based on the acquisition of the tire contact lengths S _R1 , S _L1 , S _R2 , S _L2 and the wheel loads W _R1 , W _L1 , W _R2 , W _L2 . The excess or deficiency of the tire air pressure of each of the wheels 11a, 11b, 12a and 12b can be predicted. As a result, the tire air pressure calculator 56 can determine whether the tire air pressure of each wheel 11a, 11b, 12a, 12b is good or bad.

For example, in such a determination, threshold values of the tire contact lengths S _R1 , S _L1 , S _R2 , and S _L2 for the wheel weights W _R1 , W _L1 , W _R2 , and W _L2 of the wheels 11a, 11b, 12a, and 12b are set in advance. In addition, based on the calculated values of the wheel weights W _R1 , W _L1 , W _R2 , W _{L2 and} the calculated values of the tire contact lengths S _R1 , S _L1 , S _R2 , S _L2 , the tire pressure is predicted to be excessive or insufficient. Also good.

Further, if the legal upper limit value of the wheel weights W _R1 , W _L1 , W _R2 , and W _L2 of the vehicle 10 is, for example, 5 tons, the tire contact lengths S _R1 , S _L1 , S _R2 , S in the tire of the vehicle 10 The upper limit value S1max (5 tons) of _L2 can be determined naturally. Therefore, when any of the tire contact lengths S _R1 , S _L1 , S _R2 , and S _L2 exceeds the upper limit value S1max (5 tons), the wheel weights W _R1 , W _L1 , W _R2 , and W _L2 are related. Alternatively, the tire pressure may be predicted to be abnormal (here, the tire pressure is insufficient).

Further, the upper limit values S2max (A inch), S2max (B inch),... Of the tire contact lengths S _R1 , S _L1 , S _R2 , S _L2 corresponding to the tire size of the vehicle 10 are stored in advance in the memory 48 as table data. By doing so, it is possible to predict a fine abnormality in tire pressure (here, insufficient tire pressure). For example, when any of the tire ground contact lengths S _R1 , S _L1 , S _R2 , and S _L2 exceeds the upper limit value S2max (A inch), the control device 40A uses appropriate notification means (not shown). A warning to the driver such as “If the installed tire size is A inch, it is considered that the tire air pressure is insufficient, so please adjust the tire air pressure” can be notified.

  In this example, the method of deriving the tire contact length for each of the left and right wheels 11a, 11b, 12a, 12b of the vehicle 10 has been described. However, the calculation of the tire contact length of the vehicle 10 is not necessarily limited to this. .

For example, assuming that the tire ground contact length S is the same in all the wheels 11a, 11b, 12a, 12b, the tire ground contact length S may be simply formulated. Even in this case, it may be beneficial to easily predict whether the tire pressure is excessive or insufficient. That is, the computing unit 49 uses the output waveforms (time waveforms) of the load cells LC1 to LC4 to assume the tire ground contact lengths S of the left and right wheels 11a, 11b, 12a, 12b of the vehicle 10 are the same. The length S is calculated, and the quality of the tire air pressure of the wheels 11a, 11b, 12a, 12b can be easily determined based on the tire contact length S and the wheel weights W _R1 , W _L1 , W _R2 , W _L2 .

(Modification)
Next, modifications of the new axle load scale 100 of the first embodiment and the new axle load scale 200 of the second embodiment will be described. From the above description, for those skilled in the art, the new axle load scales 100 and 200 can be variously modified as follows.

<First Modification>
In the new axle load scale 100 of the first embodiment and the new axle load scale 200 of the second embodiment, as shown in FIGS. 3 and 10, a rectangular plate having substantially the same shape (slightly smaller) as the pit portion 21A of the installation base 25. By carving the entire left rear part of the body into a rectangular shape, a platform vehicle stacking part constituting the axle load measuring surface 21 and the wheel load measuring surface 22 is formed.

  However, as in the new axle load scales 100A and 200A of this modification (FIG. 13), the entire left front portion of the rectangular plate is scraped into a rectangular shape to constitute the axle load measuring surface 21A and the wheel load measuring surface 22A. A platform vehicle loading section can be formed. In this case, the vehicle 10 enters from “front” of the protruding platform 20A (N = 2) and exits from “rear” of the protruding platform 20A (N = 2).

  Further, as in the present modified example (FIG. 14), by placing the rectangular parallelepiped plate of the mother partly in the thickness direction, the platform vehicle loading portion (the vehicle load measuring surface 521 and the wheel load measuring surface 522). That is, a portion excluding the thin portion of the rectangular plate body 520 can be formed. In this case, a lid member 526 fixed to the installation base 525 using an appropriate fixing means 527 is disposed so as to cover almost the entire cutting area. The lid member 526 is cut off at the connection with the rectangular plate body 520. Even if the left wheels 11b and 12b of the vehicle 10 are placed on the lid member 526, the load of the vehicle 10 is a rectangular plate body. Not transmitted to 520. With this configuration, the rigidity of the rectangular plate body 520 can be increased, so that the strength of the mounting vehicle stacking portion forming the axle load measurement surface 521 and the mounting vehicle stacking portion forming the wheel load measurement surface 522 can be improved.

<Second Modification>
In the new axle load scale 100 of the first embodiment and the new axle load scale 200 of the second embodiment, the example using the protruding platform 20 (N = 2) as the new platform has been described. It is not limited to the protruding shape.

  As shown in FIG. 15, the new axle weight scales 100B and 200B with a window-type platform 20B (N = 2) can load both left and right wheels 11a, 11b, 12a and 12b of the vehicle 10, Only the left and right wheels (here, the right wheels 11a and 12a) of the vehicle 10 can be loaded on the axle load measurement surface 21B used for measuring the axle load of the first and second shafts 13 and 10, and the vehicle 10 A wheel weight measurement surface 22B used for wheel weight measurement of only one of the left and right wheels (here, the right wheels 11a and 12a) is provided.

  As shown in FIG. 15, in the new axle load scales 100B and 200B of the present modification, the left rear portion of the rectangular plate body having the same shape (slightly smaller) as the pit portion 21A of the installation base 25 is cut into a rectangular window shape. As a result, a rectangular window portion 150 is formed, and as a result, a mounting vehicle stacking portion forming the axle load measurement surface 21B and a mounting vehicle stacking portion forming the wheel load measurement surface 22B are formed. In this case, a portion of the rectangular plate adjacent to the rectangular window 150 in the approach direction (front-rear direction) of the vehicle 10 corresponds to the mounting vehicle stacking portion constituting the axle load measurement surface 21B and is orthogonal to the approach direction. A portion of the rectangular plate that is adjacent to the rectangular window 150 in the direction (left-right direction) corresponds to the platform vehicle stacking portion constituting the wheel load measuring surface 22B.

  Further, the lid member 26B is provided for the purpose of closing the pit space in the rectangular window 150 of the windowed mounting base 20B (N = 2).

In the design of dimensions L ′ ₁ and L ′ ₂ in the front-rear direction of the window-mounted platform 20B (N = 2), the center line of the window-mounted platform 20B (N = 2) and the front end of the rectangular window 150 distance corresponding to the dimension "[Delta] L between the corresponding dimension" [Delta] L _'2 "to the distance, the rear end portion of the rear end portion and a rectangular window portion 150 of the window-shaping the platform 20B (N = 2) between _'1 "may take in half _{(ΔL' 2 = ΔL '1} /2).

In the new axle load scales 100B and 200B of the present modified example, the dimensions L ′ ₁ and L ′ ₂ are the dimensions L ₁ and L ₂ (FIG. 2 and FIG. 2) in the design of the protruding platform 20 (N = 2). Therefore, the wheel load measurement allowance and the shaft load measurement allowance of the new axle load scales 100B and 200B are α ₁ and α _{2 in} the case of the new axle load types 100 and 200 (see FIG. 2). There is a disadvantage that it is smaller than that of (see).

  On the other hand, in the new axle load scales 100B and 200B of this modification, as shown in FIG. 15, the position of the first load cell LC1 ′ is moved to the left rear corner of the window-mounted platform 20B (N = 2). Therefore, there is an advantage that the support position of the window-mounted platform 20B (N = 2) can be arranged symmetrically in the front-rear direction and the left-right direction.

  Regarding the function of the wheel load calculation unit 51, the function of the axle load calculation unit 54, the function of the total weight calculation unit 53, and the function of the gravity center position calculation unit 52 of the new axle load meter 100B, refer to the description of the first embodiment. Thus, the function of the tire air pressure calculation unit 56 of the new axle load gauge 200B can be easily understood by referring to the description of the second embodiment. Therefore, detailed description thereof is omitted here.

  Further, in place of the window-equipped platform 20B (N = 2), a window-equipped platform (N = n + 1, N = 2n-1) may be used.

  Further, as in the first modified example (FIG. 14), the left rear portion of the rectangular plate is partially cut into a window shape in the thickness direction, thereby providing a window-mounted platform 20B (N = 2). It is possible to form a platform vehicle loading section that constitutes the same kind of axle load measurement surface and wheel load measurement surface.

<Third Modification>
In the new axle load scale 100 of the first embodiment and the new axle load scale 200 of the second embodiment, the example using the protruding platform 20 (N = 2) as the new platform has been described. It is not limited to the protruding shape.

  The notched platform 20C (N = 2) of the new axle scales 100C and 200C of this modification can load both the left and right wheels 11a, 11b, 12a and 12b of the vehicle 10 as shown in FIG. Only the left and right wheels (here, the right wheels 11a and 12a) of the vehicle 10 can be loaded, and the axle load measuring surface 21C used for measuring the axle weight of the first shaft 13 and the second shaft 14 can be loaded. A wheel weight measuring surface 22C used for wheel weight measurement of only one of the left and right wheels (here, the right wheels 11a and 12a) is provided.

  As shown in FIG. 16, in the new axle load scales 100C and 200C of this modification, the left rear portion of the rectangular plate body having the same shape (slightly smaller) as the pit portion 21A of the installation base 25 is moved in the left-right direction from the left end portion. The platform vehicle stacking portion constituting the axle load measurement surface 21C and the wheel load measurement surface 22C is formed by cutting into a rectangular and concave shape. In this case, in the approach direction (front-rear direction) of the vehicle 10, the rectangular plate portion adjacent to the rectangular and concave cutout corresponds to the mounting vehicle stacking portion constituting the axle load measuring surface 21 </ b> C, and the approach direction In the direction (left-right direction) orthogonal to the notch portion, the portion of the rectangular plate adjacent to the notch portion corresponds to the mounting vehicle stacking portion constituting the wheel load measuring surface 22C.

  In addition, a lid member 26C is provided for the purpose of closing the rectangular pit space of the notched platform 20C (N = 2).

  As described above, in the new axle load scales 100C and 200C of this modification, as shown in FIG. 16, the position of the first load cell LC1 ′ is moved to the left rear corner of the notched platform 20C (N = 2). Therefore, there is an advantage that the support position of the notch type mounting base 20C (N = 2) can be arranged symmetrically in the front-rear direction and the left-right method.

  In addition, about the dimension design method of the notch type mounting base 20C (N = 2), it can be easily understood by taking into account the dimension design of the windowed mounting base 20B (N = 2) of the second modified example. Regarding the function of the wheel load calculation unit 51, the function of the axle load calculation unit 54, the function of the total weight calculation unit 53, and the function of the gravity center position calculation unit 52 of the new axle load meter 100C, refer to the description of the first embodiment. This makes it easy to understand, and the function of the tire air pressure calculation unit 56 of the new axle load meter 200C can be easily understood by referring to the description of the second embodiment. Therefore, detailed description thereof is omitted here.

  Moreover, it can replace with the notch type mounting base 20C (N = 2), and can also use the notch type mounting base (N = n + 1, N = 2n-1) in which the said notch part was formed in the left-right direction.

  Further, as in the first modified example (FIG. 14), the left rear part of the rectangular plate body is partially cut into a rectangular shape and a concave shape in the thickness direction, thereby forming a notch-shaped platform 20C (N = 2). It is possible to form a platform vehicle loading section that constitutes the same kind of axle load measurement surface and wheel load measurement surface.

<Fourth Modification>
In the new axle load scale 100 of the first embodiment and the new axle load scale 200 of the second embodiment, the example using the protruding platform 20 (N = 2) as the new platform has been described. It is not limited to the protruding shape.

  The notched platform 20D (N = 2) of the new axle load scales 100D and 200D of this modification can load both the left and right wheels 11a, 11b, 12a and 12b of the vehicle 10 as shown in FIG. The axle load measurement surface 21D used for measuring the axle weight of the first shaft 13 and the second shaft 14 and only one of the left and right wheels (here, the right wheels 11a and 12a) of the vehicle 10 can be loaded. A wheel weight measuring surface 22D used for wheel weight measurement of only one of the left and right wheels (here, the right wheels 11a and 12a) is provided.

  As shown in FIG. 17, in the new axle load scales 100D and 200D of the present modification, the rear left part of the rectangular plate that is substantially the same shape (slightly smaller) as the pit part of the installation base 25 ′ is moved back and forth from the rear end part. The platform vehicle loading portion constituting the axle load measurement surface 21D and the wheel load measurement surface 22D is formed by scraping in a rectangular and concave shape in the direction. In this case, in the approach direction (front-rear direction) of the vehicle 10, the rectangular plate portion adjacent to the rectangular and concave cutout corresponds to the mounting vehicle stacking portion constituting the axle load measurement surface 21 </ b> D, and the approach direction In the direction (left-right direction) orthogonal to the notch portion, the portion of the rectangular plate adjacent to the notch portion corresponds to the mounting vehicle stacking portion constituting the wheel load measuring surface 22D.

  Further, the lid member 26D is provided for the purpose of closing the rectangular pit space of the notch-shaped mounting base 20D (N = 2).

  At this time, the wheel load measuring surface 22D is configured to be wider than the left rear protruding surface 300, and similarly to the protruding platform 20 (N = 2) of the new axle load scales 100, 200, Only one of the left and right wheels (here, the right wheels 11a and 12a) is set to a width dimension that allows the wheel weight measurement surface 22D to be ridden.

  Further, the projecting surface 300 is configured to be narrower than the platform vehicle stacking portion constituting the wheel load measuring surface 22D, and either the left or right wheel of the vehicle 10 (here, the right wheels 11a and 12a) is provided. When riding on the wheel load measuring surface 22 </ b> D, the left or right wheel of the vehicle 10 (here, the left wheels 11 b and 12 b) is set to a width dimension that does not ride on the protruding surface 300.

  That is, when one of the left and right wheels (here, the right wheels 11a and 12a) of the vehicle 10 is on the wheel load measuring surface 22D, either the left or right wheel of the vehicle 10 (here, the left wheels 11b and 12b). ) Passes through the notch (that is, on the lid member 26D) of the notch-shaped mounting base 20D (N = 2) between the wheel load measuring surface 22D and the protruding surface 300.

  In this case, means for preventing the vehicle 10 from entering the protruding surface 300 in the vicinity of the protruding surface 300 (for example, a pole or a guide plate not shown) so that the vehicle 10 does not accidentally enter the protruding surface 300 from behind. ) May be arranged.

  As described above, in the new axle load scales 100D and 200D of the present modified example, as shown in FIG. 17, the position of the first load cell LC1 ′ is moved to the left rear corner of the notched platform 20D (N = 2). Therefore, there is an advantage that the support position of the notch type mounting table 20D (N = 2) can be arranged symmetrically in the front-rear direction and the left-right method.

  In addition, about the dimension design method of notch type mounting base 20D (N = 2), it can understand easily by taking into consideration the dimension design of the protrusion type mounting base 20 (N = 2) of 1st Embodiment. Regarding the function of the wheel load calculation unit 51, the function of the axle load calculation unit 54, the function of the total weight calculation unit 53, and the function of the gravity center position calculation unit 52 of the new axle load meter 100D, refer to the description of the first embodiment. Thus, the function of the tire pressure calculation unit 56 of the new axle load meter 200D can be easily understood by referring to the description of the second embodiment. Therefore, detailed description thereof is omitted here.

  Moreover, it can replace with the notch type mounting base 20D (N = 2), and can also use the notch type mounting base (N = n + 1, N = 2n-1) in which the said notch part was formed in the front-back direction.

  Further, as in the first modified example (FIG. 14), the rear left part of the rectangular plate body is partially cut into a rectangular shape and a concave shape in the thickness direction, thereby forming a notch-shaped platform 20D (N = 2). It is possible to form a platform vehicle loading portion that constitutes the same axle load measurement surface and wheel load measurement surface.

<Fifth Modification>
In the new axle load scale 100 of the first embodiment and the new axle load scale 200 of the second embodiment, it is assumed that only the right wheels 11a and 12a of the vehicle 10 are on the wheel load measurement surface 22. Not limited to.

  For example, in the new axle load scales 100E and 200E of the present modified example, as shown in FIG. 18, only the right wheels 11a and 12a of the vehicle 10 are formed at the right rear part of the notch-shaped mounting base 20E (N = 2). The second wheel weight measuring surface can be mounted on the first wheel weight measuring surface 122E, and only the left wheels 11b and 12b of the vehicle 10 are formed on the left rear portion of the notched platform 20E (N = 2). You can ride 222E.

  Here, as shown in FIG. 18, the width of the first wheel weight measuring surface 122E, the width of the second wheel weight measuring surface 222E, and between the first wheel weight measuring surface 122E and the second wheel weight measuring surface 222E. The width of the rectangular cutout portion of the cutout mounting base 20E (N = 2) is set to substantially the same dimension. That is, in the new axle weight scales 100E and 200E of the present modification, the central rear portion of the rectangular plate having the same shape (slightly smaller) as the pit portion of the installation base 25 ′ is rectangular and concave in the front-rear direction from the rear end portion. Thus, a platform vehicle stacking portion constituting the axle load measuring surface 21E, the first wheel weight measuring surface 122E, and the second wheel weight measuring surface 222E is formed. In this case, in the approach direction (front-rear direction) of the vehicle 10, a rectangular plate portion adjacent to the rectangular and concave cutout corresponds to the mounting vehicle stacking portion constituting the axle load measuring surface 21 </ b> E, and the approach direction In the direction (left-right direction) perpendicular to the notch, the portion of the rectangular plate adjacent to the notch corresponds to the platform vehicle stacking portion constituting the first wheel weight measuring surface 122E and the second wheel weight measuring surface 222E. Yes.

  Further, a lid member 26E is provided for the purpose of closing the pit space of the notch portion of the notch mount 20E (N = 2).

  In this way, when the right wheels 11a and 12a of the vehicle 10 get on the first wheel weight measurement surface 122E, the left wheels 11b and 12b of the vehicle 10 do not get on the second wheel weight measurement surface 222E and Part (that is, on the lid member 26E). Conversely, when the left wheels 11b and 12b of the vehicle 10 are on the second wheel weight measuring surface 222E, the right wheels 11a and 12a of the vehicle 10 are not on the first wheel weight measuring surface 122E, and the notch ( That is, it passes over the lid member 26E.

  As described above, in the new axle load scales 100E and 200E of the present modification example, the vehicle 10 enters the notch-shaped platform 20E (N = 2) from any position behind the notch-shaped platform 20E (N = 2). In addition, the right wheels 11a and 12a and the left wheels 11b and 12b of the vehicle 10 can be mounted on the notched platform 20E (N = 2) at different timings.

  Further, in the new axle load scales 100E and 200E of the present modified example, as shown in FIG. 18, the position of the first load cell LC1 ′ can be moved to the left rear corner of the notched platform 20E (N = 2). Therefore, there is an advantage that the support position of the notch type mounting base 20E (N = 2) can be arranged symmetrically in the front-rear direction and the left-right method.

  In addition, about the dimension design method of the notch type mounting base 20E (N = 2), it can be easily understood by considering the dimension design of the protruding type mounting base 20 (N = 2) of the first embodiment. For the function of the wheel load calculation unit 51, the function of the axle load calculation unit 54, the function of the total weight calculation unit 53, and the function of the center of gravity position calculation unit 52 of the new axle load meter 100E, refer to the description of the first embodiment. This makes it easy to understand, and the function of the tire pressure calculation unit 56 of the new axle scale 200E can be easily understood by referring to the description of the second embodiment. Therefore, detailed description thereof is omitted here.

  Moreover, it can replace with the notch type mounting base 20E (N = 2), and can also use the notch type mounting base (N = n + 1, N = 2n-1) in which the said notch part was formed in the front-back direction.

  Further, as in the first modified example (FIG. 14), the rear part at the center of the rectangular plate is partially cut into a rectangular shape and a concave shape in the thickness direction, thereby forming a notch-shaped platform 20E (N = 2). It is possible to form a platform vehicle loading portion that constitutes the same axle load measurement surface and wheel load measurement surface.

<Sixth Modification>
In the new axle load scale 100 according to the first embodiment and the new axle weight scale 200 according to the second embodiment, a four-wheel truck is taken as an example of the vehicle 10, and the wheel load calculation unit 51 and the gravity center position calculation unit of the new axle load scale 100. 52, the functions of the total weight calculation unit 53 and the axle load calculation unit 54, and the functions of the tire pressure calculation unit 56 of the new axle weight meter 200 are described.

  However, the measurement target of the new axle load scale described above is not limited to a four-wheel truck, and a new platform for the new axle load scale can be designed so that any multi-axle vehicle can be measured. it can.

  In this case, formulation of the functions of the wheel load calculation unit 51, the center-of-gravity position calculation unit 52, the total weight calculation unit 53, the axle load calculation unit 54, and the tire pressure calculation unit 56 is described in the first and second embodiments. It can be easily understood by referring to the explanation. Therefore, detailed description thereof will be omitted.

  According to the axle load meter of the present invention, the function of measuring the wheel load and / or the center of gravity in the width direction of the vehicle and / or the function of determining whether the tire pressure is good can be given to the conventional axle load meter. Therefore, the present invention can be used for an axle weight meter that can be used for measurement of wheel load, center of gravity position, etc. of a vehicle and determination of quality of tire air pressure.

DESCRIPTION OF SYMBOLS 10 Vehicle 11a Right wheel of front axle (first axis) 11b Left wheel of front axle (first axis) 12a Right wheel of rear axle (second axis) 12b Rear axle (second axis) Left wheel 13 Front axle (first axle)
14 Rear axle (second axle)
20 Protruding platform (new platform)
DESCRIPTION OF SYMBOLS 21 Axle load measuring surface 22 Wheel load measuring surface 25 Installation base 26 Lid member 30 Tire grounding surface 40,40A Control apparatus 41 Operation apparatus 42 Display apparatus 43 Amplifier 44 Low pass filter 45 Multiplexer 46 A / D converter 47 I / O circuit 48 Memory 49 Calculator 51 Wheel load calculator 52 Center of gravity position calculator 53 Total weight calculator 54 Axle load calculator 55 Display signal generator 56 Tire pressure calculator LC1 First load cell LC2 Second load cell LC3 Third load cell LC4 Fourth load cell 100,200 axle weight scale (new axle weight scale)

Claims (10)

Both the left and right wheels of the vehicle can be loaded, and only the left and right wheels of the vehicle can be loaded, and the axle load measuring surface used for measuring the axle load of the axle of the vehicle and the left and right wheels of the vehicle can be loaded. A wheel load measuring surface for use in measuring the wheel load of
A plurality of load cells that support the table described above from below;
An output signal from the load cell when both the left and right wheels of the vehicle are placed on the axle load measurement surface, and the load cell when only one of the left and right wheels of the vehicle is placed on the wheel load measurement surface Calculation means for calculating wheel weights of both the left and right wheels of the vehicle based on an output signal from
Axial scale equipped with. Both the left and right wheels of the vehicle can be loaded, and only the left and right wheels of the vehicle can be loaded, and the axle load measuring surface used for measuring the axle load of the axle of the vehicle and the left and right wheels of the vehicle can be loaded. A wheel load measuring surface for use in measuring the wheel load of
A plurality of load cells that support the table described above from below;
An output signal from the load cell when both the left and right wheels of the vehicle are placed on the axle load measurement surface, and the load cell when only one of the left and right wheels of the vehicle is placed on the wheel load measurement surface Calculation means for calculating the center of gravity position in the width direction of the vehicle based on an output signal from the vehicle,
Axial scale equipped with.   The axle load scale according to claim 1 or 2, wherein the calculation means calculates a tread interval of the vehicle based on the output signal. Both the left and right wheels of the vehicle can be loaded, and only the left and right wheels of the vehicle can be loaded, and the axle load measuring surface used for measuring the axle load of the axle of the vehicle and the left and right wheels of the vehicle can be loaded. A wheel load measuring surface for use in measuring the wheel load of
A plurality of load cells that support the table described above from below;
The time waveform of the output signal from the load cell when both the left and right wheels of the vehicle are placed on the axle load measurement surface, and when only one of the left and right wheels of the vehicle is placed on the wheel load measurement surface Calculating means for calculating the tire ground contact length for each of the left and right wheels of the vehicle based on the time waveform of the output signal from the load cell,
Axial scale equipped with. The axle weight meter according to claim 4 , wherein the calculation means determines whether the tire air pressure for each wheel is good or not based on a tire ground contact length for each wheel. The width of the platform of the vehicle stacking portion before forming the wheel load measurement surface is narrower than the width of the platform of the vehicle stacking portion before forming the axle load measuring surface, according to any one of claims 1 to 5 Axle weight scale. The axle load meter according to claim 6 , wherein the vehicle loading portion of the preceding table constituting the wheel load measuring surface protrudes from an end of the vehicle loading portion of the preceding table constituting the axle weight measuring surface. The vehicle loading portion of the aforementioned table that constitutes the wheel load measuring surface, and the vehicle loading portion of the preceding table that constitutes the axial weight measuring surface are formed by cutting a part of a rectangular plate, The axle weight scale according to claim 6 . When the window is formed in the rectangular plate by cutting the rectangular plate, the portion of the rectangular plate adjacent to the window in the vehicle approach direction forms the axial load measuring surface. A portion of the rectangular plate that corresponds to the vehicle loading portion of the writing table and that is adjacent to the window portion in a direction orthogonal to the approach direction corresponds to the vehicle loading portion of the preceding writing table that constitutes the wheel load measuring surface. The axle weight meter according to claim 8 . When a notch is formed in the rectangular plate by cutting the rectangular plate, the portion of the rectangular plate adjacent to the notch in the vehicle entry direction forms the axial load measuring surface. A portion of the rectangular plate that corresponds to the vehicle loading portion of the writing table and that is adjacent to the notch portion in a direction orthogonal to the entry direction corresponds to the vehicle loading portion of the preceding writing table that constitutes the wheel load measuring surface. The axle weight meter according to claim 8 .

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