JP7633627B2 - Loading weight measuring device and transport vehicle equipped with same - Google Patents

Description

The present invention relates to an on-board load weight measuring device for directly measuring the weight of a load loaded on a transport vehicle such as a dump truck (hereinafter simply referred to as a "vehicle"), and a vehicle equipped with the same.

For example, soil and sand generated during construction and civil engineering works are usually transported to treatment or disposal sites by large vehicles such as dump trucks. Large vehicles such as dump trucks can transport large amounts of soil and sand at once, but if the vehicles are driven on roads with loads exceeding the designated load capacity, they can cause physical damage to the roads and have a large impact on traffic disruptions and congestion in the event of an accident.

Therefore, it is desirable to measure the load of a vehicle and prevent overloading before it occurs. Various devices and systems for measuring the load of a vehicle have been proposed (see, for example, Patent Documents 1 and 2).

However, the load weight measuring devices and measurement systems proposed in Patent Documents 1 and 2 are installed at a specified location on the ground as platform scales, and the total weight of the loaded vehicle and the load is measured while the loaded vehicle is placed on the platform scale, and the weight of the load (load weight) is calculated by subtracting the weight of the vehicle alone from the measured value, which creates the problem of large load weight errors. Also, when measuring load weight using a platform scale, the vehicle weight before loading is measured with the platform scale, and after the load is loaded, it is measured again with the platform scale, and the load weight is calculated from the difference between the two, but it is difficult to ensure a traffic flow for the vehicle to measure twice in the limited space of a construction site, and there is also the problem that the measurement takes a long time.

When an underloaded (small) load is loaded onto a vehicle to account for errors due to the above problem, the amount of load the vehicle can carry in one trip is reduced, resulting in poor transport efficiency and an increased number of trips for the vehicle. To solve this problem, the underloaded (short) load can be added, but this requires the vehicle to travel back and forth between the loading location and the platform gauge, creating a new problem of significant time loss.

The present applicant has previously proposed an on-board load weight measuring device that can directly and highly accurately measure the weight of the load (load weight) loaded on a vehicle. This load weight measuring device is configured such that a roughly rectangular tray-shaped weighing platform for loading the load is supported by a number of load sensors installed on the vehicle bed so that it can move at least in the horizontal direction. With such a load weight measuring device, the weight of the load loaded on the weighing platform installed on the vehicle bed is directly measured by a number of load sensors, so that only the load weight can be measured directly and highly accurately, regardless of the weight of the vehicle.

Japanese Patent Application Publication No. 9-113339 Japanese Patent Application Publication No. 10-148565

However, in the above-mentioned load weight measuring device, a gap is formed between the vertical plate that rises slightly vertically from the four edges of the weighing platform and the vertical walls that rise vertically from the four edges of the vehicle's loading platform. This allows some of the load, such as soil and asphalt, to enter through this gap as debris, which accumulates in the space between the bottom of the weighing platform and the top of the loading platform, preventing the load sensor from measuring the load accurately or making measurement impossible altogether.

Therefore, the first object of the present invention is to provide a load measuring device that can accurately measure the load weight by preventing the intrusion of loads through the gap between the vertical plate of the weighing platform and the vertical wall of the loading platform.

In addition, because the load measuring device is heavy, there is a problem that the total weight of the vehicle in which the load measuring device is installed on the loading platform becomes large.

Therefore, the second object of the present invention is to provide a vehicle that can be made lighter.

In order to achieve the above object, the invention described in claim 1 is a load measuring device that is configured by installing a rectangular container-shaped weighing platform on the vehicle's loading platform using multiple load sensors. The weighing platform is configured by erecting vertical plates from the four peripheral edges of a rectangular flat base plate at approximately the same height as a vertical wall that stands vertically from the edge of the bottom plate of the loading platform, and is characterized in that the shape and dimensions of the base plate of the weighing platform are set to be approximately the same as (slightly smaller than) the shape and dimensions of the bottom plate of the loading platform, and a small gap is formed between the vertical plates of the weighing platform and the vertical walls of the loading platform.

The invention described in claim 2 is the invention described in claim 1, characterized in that a flange-shaped eaves portion is provided on the upper edge of the vertical plate of the weighing platform to cover the minute gap from above.

The invention described in claim 3 is characterized in that, in the invention described in claim 1, an elastic seal member is provided on the outer peripheral surface of the vertical plate of the weighing platform, the tip of which elastically contacts the inner peripheral surface of the vertical wall of the loading platform to seal the minute gap from above.

The invention described in claim 4 is characterized in that, in the invention described in claim 1, an elastic seal member is provided on the inner peripheral surface of the vertical wall of the loading platform, the tip of which elastically contacts the outer peripheral surface of the vertical plate of the weighing platform to seal the minute gap from above.

The invention described in claim 5 is the invention described in any one of claims 1 to 4, characterized in that three reinforcing plates are fixed to the bottom plate of the loading platform along the vehicle width direction at the front end, rear end, and middle part in the vehicle longitudinal direction, respectively, and the load sensor is disposed on both ends of each reinforcing plate in the vehicle width direction.

The invention described in claim 6 is the invention described in any one of claims 1 to 5, characterized in that the weighing platform is made of a carbon fiber or glass fiber molding.

The invention described in claim 7 is characterized in that the vehicle on whose bed the load measuring device described in any one of claims 1 to 6 is installed is a transport vehicle such as a dump truck.

According to the invention described in claim 1, a minute gap that cannot pass through debris from the load is formed between the vertical plate of the weighing platform and the vertical walls that stand vertically from the four edges of the bottom plate of the loading platform, so that debris from the load is reliably prevented from entering between the bottom surface of the weighing platform and the top surface of the loading platform, and the weight of the load (load weight) can always be measured accurately.

According to the invention described in claim 2, the minute gap is covered from above by a visor provided on the upper edge of the vertical plate of the weighing platform, and according to the inventions described in claims 3 and 4, the minute gap is covered from above by an elastic seal member, so that the intrusion of debris from the load between the bottom surface of the weighing platform and the top surface of the loading platform is reliably prevented, and the weight of the load (load weight) can always be measured accurately.

According to the invention described in claim 5, the bending deformation of the bottom plate of the loading platform is suppressed by three reinforcing plates, and a total of six load sensors are installed on the highly rigid reinforcing plate A, so that the weight of the load (load weight) placed on the weighing platform is measured with high precision by the six load sensors. Even if there is a spatial bias in the loading state of the load, the weight of the load (load weight) is measured with high precision by the six load sensors. It has been experimentally confirmed that six is the optimal number of load sensors, and that with any other number, the measurement precision is affected by the spatial bias of the load.

According to the invention described in claim 6, by constructing the weighing platform from a lightweight carbon fiber or glass fiber molding, it is possible to reduce the weight of the load weight measuring device equipped with the weighing platform.

According to the invention described in claim 7, the vehicle equipped with the load measuring device has multiple openings formed in the left and right side walls of the vertical walls of the loading platform, which allows the loading platform and the entire vehicle to be lighter in weight.

1 is a side view of a vehicle according to the present invention. 1 is a cutaway plan view of a loaded weight measuring device according to the present invention; 3 is a cross-sectional view taken along line AA in FIG. 2. 3 is a cross-sectional view taken along line BB in FIG. 2. 1 is a configuration diagram of a loaded weight measurement system using a load sensor of a loaded weight measurement device according to the present invention; FIG. 5 is a view similar to FIG. 4, showing another embodiment 1 of the present invention. FIG. 7 is an enlarged detailed view of part C in FIG. 6 . FIG. 5 is a view similar to FIG. 4, showing another embodiment 2 of the present invention. FIG. 9 is an enlarged detailed view of part D in FIG. 8 .

The following describes an embodiment of the present invention with reference to the attached drawings.

Figure 1 is a side view of a vehicle equipped with a loaded weight measuring device according to the present invention. The vehicle 100 shown in Figure 1 is a dump truck with a loading platform 110 extending horizontally rearward from a cabin 101 at the front end. Here, the loading platform 110 can rotate upward (in the direction of the arrow) around its rear end as shown by the dotted line in Figure 1, and as the loading platform 110 rotates and tilts relative to the horizontal in this way, the load W, such as soil and sand, loaded on the loading platform 110 falls and is removed from the loading platform 110.

The loading weight measuring device 1 (see Figures 2 to 5) according to the present invention is installed on the loading platform 110. The configuration of this loading weight measuring device 1 will be described below with reference to Figures 2 to 5.

Figure 2 is a broken plan view of the load weight measuring device according to the present invention, Figure 3 is a cross-sectional view taken along line A-A in Figure 2, Figure 4 is a cross-sectional view taken along line B-B in Figure 2, and Figure 5 is a configuration diagram of a load weight measuring system using a load sensor in the load weight measuring device. In the following explanation, the directions of the arrows shown in Figures 2 to 4 are referred to as the "front-rear", "left-right" and "up-down" directions, respectively.

The load weight measuring device 1 according to the present invention is installed on the loading platform 110 of the dump truck 100 as described above, and has a weighing platform 2 in the shape of a rectangular container with an open top, as shown in Figs. 2 to 4. The weighing platform 2 is composed of a rectangular base plate 3 and vertical plates 4 standing vertically from the four periphery edges of the base plate 3. The vertical plates 4 are composed of a front plate 4A standing vertically from the front edge of the base plate 3, a rear plate 4B standing vertically from the rear edge of the base plate 3, and side plates 4C standing vertically from the left and right side edges of the base plate 3. The rear plate 4B is supported by a hinge (not shown) so that it can rotate up and down around its upper edge, and when a load W is loaded onto the weighing platform 2, the rotation of the rear wall 4B is locked by a locking mechanism (not shown).

Also, vertical walls 112 stand up on the four periphery edges of the rectangular bottom plate 111 of the loading platform 110 shown in Figures 2 to 4. Specifically, the vertical walls 112 are composed of a front wall 112A that stands up vertically from the front edge of the bottom plate 111 of the loading platform 110, a rear wall 112B that stands up vertically from the rear edge of the bottom plate 111, and left and right side walls 112C that stand up vertically from the left and right side edges of the bottom plate 111. Here, as shown in Figures 3 and 4, the height dimensions of the vertical walls 112 of the loading platform 110 (the rear wall 112B and the left and right side walls 112C excluding the front wall 112A) and the vertical plates 4 of the weighing platform 2 (the rear plate 4B and the left and right side plates 4C excluding the front plate 4A) are set to be approximately the same height.

The rear wall 112B of the loading platform 110 is supported by a hinge (not shown) so that it can rotate up and down around its upper edge, and the rotation of the rear wall 112B is locked by a locking mechanism (not shown) except when the load W is being unloaded. Therefore, when the load W is being loaded onto the loading platform 110 (actually, the weighing platform 2 of the load weight measuring device 1) or when the vehicle 100 is traveling with the load W loaded, the rear wall 112B remains in a vertically upright position.

In this embodiment, as shown in FIG. 2, the shape and dimensions of the base plate 3 of the weighing platform 2 are set to be approximately the same as (slightly smaller than) the shape and dimensions of the bottom plate 111 of the loading platform 110, and a minute gap δ is formed between the vertical plate 4 (front wall 4A, rear wall 4B, and left and right side plates 4C) of the weighing platform 2 and the vertical wall 112 (front wall 112A, rear wall 112B, and left and right side walls 112C) of the loading platform 110, so that fragments and debris of the load W cannot pass through. Although not shown, the weighing platform 2 is connected at its front end to the front end of the loading platform 110 so that it can move back and forth and left and right by an amount equal to or smaller than the minute gap δ.

As shown in Figures 2 and 3, three channel-shaped reinforcing plates 113 are fixed along the vehicle width direction to the front and rear ends and the middle part in the fore-aft direction on the bottom plate 111 of the loading platform 110 of the vehicle 100. As shown in Figure 2, a load cell 5, which is a load sensor, is disposed on both the left and right ends of each reinforcing plate 113. Here, as shown in Figures 3 and 4, each load cell 5 is disposed between the reinforcing plate 113 and the base plate 3 of the weighing platform 2 via a shim 6 for adjusting the height.

Therefore, in this embodiment, a total of six load cells 5 are arranged, and as shown in FIG. 2, the weighing platform 2 is supported on the loading platform 100 by the load cells 5 at six locations, including the four corners and the left and right of the center in the front-rear direction. Here, each load cell 5 is a sensor that converts the load into an electrical signal, and as shown in FIG. 5, the six load cells 5 indicated by the symbols "LC1" to "LC6" are electrically connected to the summation board 7. The summation board 7 is then connected to the indicator 9 via a signal line 8. As shown in FIG. 1, the summation board 7 is arranged at the rear end of the vehicle 100, and the indicator 9 is installed inside the cabin 101 of the vehicle 100.

As shown in FIG. 5, the power (DC 24V) from the battery 10 (see FIG. 1), which is a DC power source mounted on the vehicle 100, is converted to AC (AC 100V) by the DC/AC converter 11 and supplied to the indicator 9 and the external indicator 12. Here, the DC/AC converter 11 and the external display 12 are respectively disposed on the upper part of the front wall 112A erected at the front end of the cabin 101 and the loading platform 110 of the vehicle 100, as shown in FIG. 1.

In a vehicle 100 in which the load weight measuring device 1 configured as described above is installed on the loading platform 110, a load W is placed on the rectangular container-shaped weighing platform 2 of the load weight measuring device 1 and its weight is measured.

That is, the weight of the load W loaded on the weighing platform 2 is detected by six load cells 5, and the detection signals are sent to the summing board 7 shown in FIG. 5. The summing board 7 then calculates the load weight using a predetermined formula based on the detection signals sent from each load cell 5, and the result is sent to the indicator 9 via signal line 8 and displayed on the indicator 9, while the same result is sent from the indicator 9 via signal line 13 to the external display 12 and displayed digitally on the external display 12.

In the load weight measuring device 1 according to this embodiment, the weight (load weight) of the load W loaded on the weighing platform 2 installed on the loading platform 110 of the vehicle 100 (see FIG. 1) is directly measured by a total of six load cells 5, so that only the load weight can be measured directly and with high accuracy, regardless of the weight of the vehicle 100. In particular, because the weighing platform 2 can move horizontally, only the net weight (vertical load) of the load W on the weighing platform 2 can be measured directly and with high accuracy. Therefore, there is no need to load an insufficient (small) load W onto the vehicle 100 in anticipation of measurement errors, and the efficiency of transporting the load W by the vehicle 100 is improved.

In addition, in the load weight measuring device 1 according to this embodiment, the bending deformation of the bottom plate 111 of the loading platform 110 is suppressed by the three reinforcing plates 113, and a total of six load cells 5 are installed on the highly rigid reinforcing plates 113, so that the weight (load weight) of the load W loaded on the weighing platform 2 is measured with high precision by the six load cells 5. In this case, even if there is a spatial bias in the loading state of the load W, the weight (load weight) of the load W is measured with high precision by the total of six load cells 5. Note that it has been experimentally confirmed that six is the optimal number of load cells 5, and that with any other number, the measurement accuracy is affected by the spatial bias of the load W.

In the load weight measuring device 1 according to this embodiment, as described above, the shape and dimensions of the base plate 3 of the weighing platform 2 are set to be approximately the same as (slightly smaller than) the shape and dimensions of the bottom plate 111 of the loading platform 110, and a minute gap δ is formed between the vertical plate 4 (front wall 4A, rear wall 4B, and left and right side plates 4C) of the weighing platform 2 and the vertical wall 112 (front wall 112A, rear wall 112B, and left and right side walls 112C) of the loading platform 110. This prevents fragments and debris of the load W from passing through the minute gap δ and entering the space between the bottom surface of the weighing platform 2 and the top surface of the loading platform 110 and accumulating there. Therefore, the weight of the load W is not received by a part of the load W that has entered the space between the bottom surface of the weighing platform 2 and the top surface of the loading platform 110 and accumulated there, and all of the load weight is measured with high precision by the six load cells 5.

Furthermore, in the load weight measuring device 1 according to this embodiment, as shown in Figures 3 and 4, the vertical plates 4 (front plate 4A, rear plate 4B, and left and right side plates 4C) are vertically raised from the four periphery of the weighing platform 2 to approximately the same height as the rear wall 112B and side wall 112C of the loading platform 110, making the weighing platform 2 a rectangular container with an open top, so that the load W loaded on the weighing platform 2 does not come into contact with the vertical walls 112 (front wall 112A, rear wall 112B, and left and right side walls 112C) of the loading platform 110 of the vehicle 100 (see Figure 1). Therefore, the vertical walls 112 (front wall 112A, rear wall 112B, and left and right side walls 112C) of the loading platform 110 do not receive lateral force from the load W. Therefore, when the load W comes into contact with the vertical walls 112 (front wall 112A, rear wall 112B, and left and right side walls 112C) of the loading platform 110, the weight (vertical load) of the load W is not reduced by the upward (antigravity) frictional force that occurs between the two, and only the weight (load weight) of the load W on the weighing platform 2 is measured directly and with high precision.

In this embodiment, the weighing platform 2 is made of steel, but if the weighing platform 2 is made of a lightweight carbon fiber or glass fiber molding, the weight of the weighing platform 2 and the load weight measuring device 1 equipped with the weighing platform 2 can be reduced.

In addition, at least the left and right side walls 112C of the vertical walls 112 of the loading platform 110 of the vehicle 100 have a ladder-shaped frame body left behind, and the steel surface members within the frame are removed to form a plurality of rectangular openings 112a (four on each side in the illustrated example) as shown in FIG. 1 (only one formed in one side wall 112C is shown in FIG. 1) to reduce the weight of the loading platform 110. In this case, the left and right side panels 4C of the weighing platform 2 located inside the side walls 112C of the loading platform 110 are exposed from the openings 112a, so various information such as letters and symbols can be displayed on the outer surface of the exposed parts, and the information can be made visible to a third party through the openings 112a in the left and right side walls 112C of the loading platform 110.

In the above embodiment, the shape and dimensions of the base plate 3 of the weighing platform 2 are set to be substantially the same as (slightly smaller than) the shape and dimensions of the bottom plate 111 of the loading platform 110, and a minute gap δ is formed between the vertical plate 4 (front wall 4A, rear wall 4B, and left and right side plates 4C) of the weighing platform 2 and the vertical wall 112 (front wall 112A, rear wall 112B, and left and right side walls 112C) of the loading platform 110, thereby preventing a part of the load W (fragments or debris) from passing through the minute gap δ. However, if a configuration is adopted in which the minute gap δ is blocked from above, it is possible to reliably prevent the occurrence of a situation in which a part of the load W passes through the minute gap δ. Examples of this are described below as alternative embodiments 1 and 2 with reference to Figures 6 to 9.

Figure 6 is a view similar to Figure 4 showing Alternative Form 1, and Figure 7 is an enlarged detailed view of part C in Figure 6. In the example shown in these figures, the upper edge of the vertical wall 4 of the weighing platform 2 (Figure 6 shows only the left and right side panels 4C) is bent outward at a right angle to form a flange-shaped eaves portion 4a, which covers the minute gap δ from above.

As described above, when the minute gap δ is covered from above by the eaves portion 4a formed along the upper edge of the vertical wall 4 of the weighing platform 2, fragments and debris of the load W are reliably prevented from passing through the minute gap δ, so that no part of the load W penetrates and accumulates between the bottom surface of the weighing platform 2 and the upper surface of the loading platform 110, and the weight of the load W (loading weight) is always measured accurately. Although not shown, a gap similar to the minute gap δ is also set between the upper end surface 112a of the side wall 112C of the loading platform 110 and the lower surface of the eaves portion 4a.

In addition, Fig. 8 is a view similar to Fig. 4 showing Alternative Form 2, and Fig. 9 is an enlarged detailed view of part D in Fig. 8. In the example shown in these figures, an elastic seal member 20 is provided on the outer peripheral surface of the vertical plate 4 (left and right side plates 4C in the illustrated example) of the weighing platform 2, with its tip elastically contacting the inner peripheral surface of the vertical wall 112 (left and right side walls 112C in the illustrated example) of the loading platform 110 to seal the minute gap δ from above. The installation position of the elastic seal member 20 is preferably near the upper end of the side wall 112C of the loading platform 110 or the side plate 4C of the weighing platform 2.

As described above, when the minute gap δ is covered from above by the elastic seal member 20 provided on the outer peripheral surface of the vertical plate 4 of the weighing platform 2, the elastic seal member 20 reliably prevents fragments and debris of the load W from passing through the minute gap δ. This prevents part of the load W from entering and accumulating between the bottom surface of the weighing platform 2 and the top surface of the loading platform 110, and allows the weight of the load W (load weight) to be measured accurately at all times.

Although not shown, an elastic seal member similar to that described above can be provided on the inner peripheral surface of the vertical wall 112 of the loading platform 110, and the tip of this elastic seal member can be brought into elastic contact with the outer peripheral surface of the vertical plate 4 of the weighing platform 2 to cover the minute gap δ from above. This reliably prevents fragments and debris from the load W from passing through the minute gap δ, so that no part of the load W will penetrate and accumulate between the bottom surface of the weighing platform 2 and the top surface of the loading platform 110, and the weight of the load W (load weight) can always be measured accurately.

In the above embodiment, a load cell 5 is used as the load sensor, but any other load sensor can be used as long as it converts the load into an electrical signal.

In addition, the present invention is not limited to the above-described embodiment, and various modifications are possible within the scope of the claims and the technical ideas described in the specification and drawings.

REFERENCE SIGNS LIST 1 Loaded weight measuring device 2 Weighing platform 3 Base plate of weighing platform 4 Vertical plate of weighing platform 4A Front plate 4B Rear plate 4C Side plate 4a Eaves 5 Load cell (load sensor)
7 summing board 9 indicator 10 battery 11 DC/AC converter 12 external display 20 elastic seal member 100 vehicle (transport vehicle)
110 Loading platform 111 Bottom plate of loading platform 112 Vertical wall of loading platform 112A Front wall 112B Rear wall 112C Side wall 112a Opening of loading platform side wall 113 Reinforcement plate W Load δ Minute gap

Claims (7)

A load measuring device is configured by installing a rectangular container-shaped weighing platform on a vehicle bed using a plurality of load sensors, the weighing platform being configured by vertically standing vertical plates on the four periphery edges of a rectangular flat base plate,
The loading platform has a plurality of openings formed in at least the left and right side walls of a vertical wall that stands vertically from the four peripheral edges of a bottom plate by removing a surface member from a frame body;
The weighing platform has a base plate whose shape and dimensions are slightly smaller than the shape and dimensions of the bottom plate inside the loading platform, and a small gap is formed between the vertical plate of the weighing platform and vertical walls that rise vertically from the four peripheral edges of the bottom plate of the loading platform. The load weight measuring device according to claim 1, characterized in that a flange-shaped eaves portion that covers the minute gap from above is provided on the upper edge of the vertical plate of the weighing platform. The load measuring device according to claim 1, characterized in that an elastic seal member is provided on the outer peripheral surface of the vertical plate of the weighing platform, the tip of which elastically contacts the inner peripheral surface of the vertical wall of the loading platform to seal the minute gap from above. The load measuring device according to claim 1, characterized in that an elastic seal member is provided on the inner peripheral surface of the vertical wall of the loading platform, the tip of which elastically contacts the outer peripheral surface of the vertical plate of the weighing platform to seal the minute gap from above. The load measuring device according to any one of claims 1 to 4, characterized in that three reinforcing plates are fixed on the bottom plate of the loading platform along the vehicle width direction at the front and rear ends and the middle part in the vehicle's fore-and-aft direction, respectively, and the load sensor is disposed on both ends of each reinforcing plate in the vehicle width direction. 6. A live load measuring device according to claim 5 , wherein the weighing platform is made of a molded material of carbon fiber or glass fiber. A transport vehicle such as a dump truck, comprising the load measuring device according to claim 6 .

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