JP3525409B2 - Vehicle loading weight detector - Google Patents

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a vehicle weight detection device for displaying the weight loaded on the bed of a vehicle, particularly a freight carrier, to prevent overloading.

[0002]

2. Description of the Related Art A conventional vehicle load weight detecting device detects a load applied to a cargo bed by sensors provided on front and rear wheels of a vehicle, and detects a load weight based on a signal output from the sensor and changing according to the load. Was calculated and displayed on the display, and an alarm was issued when the loaded weight was overloaded. However, when the vehicle is running, the load applied to the sensor changes and it becomes impossible to display the accurate load weight. In order to prevent this, the loaded weight is not calculated during traveling.

By the way, the calculation of the load weight in the above-mentioned conventional vehicle load weight detecting device is performed by operating a switch manually operated at the start of loading / unloading work, or by a fixed time after the vehicle is stopped from running. The process was started in response to detection that the difference between the calculated load weight at the time when the time elapses and the weight calculated thereafter became a predetermined value or more.

[0004]

In a vehicle for transporting cargo such as a box-shaped carrier, in order for the vehicle load weight detection device to detect the loaded weight, the door of the box-shaped carrier is opened and the operation switch is manually operated. Had to do. When the start of loading / unloading work is detected by operating the switches that are manually operated in this way, in order to calculate an accurate load weight in loading / unloading work, the operation of opening the door of the loading platform and the manual operation of the operation switch are required. The conventional vehicle load weight detection device has a problem that the operation becomes indispensable, it takes time and effort to calculate the load weight, and the operation is troublesome.

In particular, when the operation switch is located in the driver's seat, when carrying out loading / unloading work, the operator manually operates the operation switch in the driver's seat and then opens the door of the loading platform to load the product. -Since the unloading work had to be performed, the work of detecting the loaded weight by the vehicle loaded weight detection device was troublesome.

[0006] Further, it is detected that the difference between the calculated load weight after a certain period of time has passed since the vehicle was stopped while the vehicle was running and the load weight calculated thereafter has exceeded a predetermined value. When detecting the start of loading / unloading work, it is necessary to always calculate the loaded weight when the vehicle is stopped.
However, since the vehicle load weight detection device is supplied with its operating power from the battery of the vehicle, if the power supply to the vehicle load weight detection device is continued when the engine is stopped and power is not being generated, There was also a problem that the battery would run out and the engine could not be started.

Therefore, the present invention has been made in view of the above problems.
An object of the present invention is to provide a vehicle load weight detection device that can calculate a load weight without bothering an operator.

[0008]

According to a first aspect of the present invention, there is provided a vehicle load weight detection device, which is mounted on a vehicle and changes in accordance with a load applied to a bed of the vehicle. A sensor 21 for generating a signal,
Loaded weight calculating means 31a for calculating and detecting the loaded weight of the loading platform of the vehicle based on the signal generated by the sensor 21.
In a vehicle load weight detection device comprising: a loading / unloading detection means 60 for detecting the opening / closing of a door of the cargo bed; and the sensor 21 and the loading only when the opening / closing detection means 60 detects the opening of the door of the cargo bed. Power supply control means 31b for controlling the weight calculation means 31a so as to supply operation power is provided.

According to the vehicle load weight detection apparatus of the present invention described in claim 1, the power supply control means 31b includes:
The sensor 21 and the loaded weight calculation means 31 only when the opening / closing detection means 60 detects the opening of the door of the loading platform.
It is controlled so as to supply the operating power supply of a. Therefore, only when the door of the platform is opened, the loaded weight calculation means 31a calculates the loaded weight of the platform based on the signal generated by the sensor 21. In this way, the loaded weight is automatically calculated according to the opening of the door of the loading platform. Moreover, only when the door of the cargo bed is opened, the sensor 21 is controlled by the power source control means 31b.
Also, since the operating power supply of the load weight calculation means 31a is supplied, the power consumption can be minimized.

In order to solve the above-mentioned problems, the invention according to claim 2 is, as shown in the basic configuration diagram of FIG. 1, in the vehicle load weight detecting device according to claim 1, the loaded weight calculation means. 31a is further provided with a display unit 41 for displaying the loaded weight, and the power supply control unit 31b is provided.
However, only when the opening / closing detecting means 60 detects the opening of the door of the cargo bed, the operating power of the sensor 21 and the loaded weight calculating means 31a is supplied and the display means 4 is supplied.
It is characterized in that the operating power supply No. 1 is supplied.

According to the vehicle load weight detecting apparatus of the present invention described in claim 2, the load weight calculating means 31a.
Even if the display means 41 for displaying the loaded weight calculated by the above is further provided, the operating power supply of the display means 41 is supplied only when the power supply control means 31b detects the opening / closing of the door of the cargo bed by the opening / closing detection means 60. Therefore, the power consumption can be minimized.

According to a third aspect of the present invention, which has been made to solve the above-mentioned problems, as shown in the basic configuration diagram of FIG. A storage unit 34 that stores and holds the loaded weight that has been displayed on the display unit 41 when closed.
The display means 41 is further characterized in that the display means 41 displays the loaded weight stored in the storage means 34 immediately after the opening / closing detection means 60 detects the opening of the door of the loading platform.

According to the vehicle load weight detection apparatus of the present invention as set forth in claim 3, when the door of the cargo bed is closed, the load weight previously displayed on the display means 41 is stored. The storage means 34 for holding is further provided, and the loaded weight stored in the storage means 34 is displayed on the display means 41 immediately after the opening / closing detection means 60 detects the opening of the door of the loading platform. Therefore, when the door of the luggage carrier is closed, the loaded weight that has been displayed on the display device 41 until then can be displayed on the display device 41 immediately after the door of the luggage carrier is opened.

In order to solve the above-mentioned problems, the invention according to claim 4 is, as shown in the basic configuration diagram of FIG. 1, in the vehicle load weight detection device according to claim 2 or 3. The display means 41 is installed on a wall surface inside the cargo bed which is visible when the door of the cargo bed is opened.

According to the vehicle load weight detection apparatus of the present invention as set forth in claim 4, the display means 41 is provided inside the cargo bed so that it can be visually recognized when the door of the cargo bed is opened. By installing it on the wall surface, it is possible to let the operator confirm the loaded weight in the loading platform during loading / unloading work.
Therefore, the operator can check the loading weight of the loading platform while loading
Since unloading work can be performed, work efficiency can be improved.

[0016]

BEST MODE FOR CARRYING OUT THE INVENTION Embodiments of a vehicle load weight detecting device according to the present invention will be described below with reference to the drawings. FIG. 2 is a diagram showing a vehicle in which the vehicle load weight detection device according to the embodiment of the present invention is arranged, and FIG.
FIG. 3B is a plan view, and FIG. 3 is an exploded perspective view of a structure for supporting the leaf spring of FIG. 2 on a carrier frame of a vehicle.
4 is a sectional view showing a sensing element provided in the shackle pin of FIG. 3, FIG. 5 is a front view of a vehicle load weight detection device according to one embodiment of the present invention, and FIG. 5 is a system configuration diagram of the vehicle load weight detection device in FIG. 5, FIG. 7 is a diagram showing a memory map of the RAM in FIG. 6, and FIG. 8 is a flowchart showing a part of the processing performed by the CPU in FIG. 9 is a flowchart showing another part of the processing performed by the CPU in FIG. 6, and FIG. 10 is a flowchart showing the offset setting processing performed by the CPU in FIG.

In FIGS. 2A and 2B, reference numeral 1 denotes a vehicle, and the vehicle 1 has wheels 3 and a box-shaped carrier 7. Wheel 3
Are provided on the front, rear, left and right, and the front two wheels and the rear two wheels are respectively supported by the left and right ends of the axle 9. The loading platform 7 has a loading platform door 7a which can be opened and closed, and is supported on the loading platform frame 5. At front and rear and left and right portions of the loading platform frame 5, a front and rear axles 9 are provided via leaf springs 11.
It is supported by the left and right ends of each.

As shown in FIG. 3, the leaf spring 11 is formed by stacking strip-shaped spring plates in a substantially arcuate shape convex toward the ground side, and both ends in the longitudinal direction are in front of and behind the luggage carrier frame 5. It is supported by two brackets 13 attached at positions spaced apart from each other, and in particular, at a rear end of the vehicle 1 by a leaf spring 11, a shackle provided between the bracket 13 and the leaf spring 11. It is supported by the placket 13 so as to be swingable. Reference numeral 17 in the drawing denotes the bracket 13 and the shackle 1.
The shackle pin which connects 5 so that rocking is possible is shown.

In the vehicle 1 having such a configuration, the sensing element 21 for measuring the loaded weight is arranged in each shackle pin 17 that connects the four brackets 13 on the front, rear, left and right sides to the shackle 15. Each sensing element 21
In the present embodiment, is a magnetostrictive gauge sensor, and as shown in FIG. 4, the web of the holding member 19 housed in the hole 17a bored from one end of the shackle pin 17 along the axial direction. It is attached to 19a. When the sensing element 21 is of the magnetostrictive type, it is fitted into the accommodation hole formed in the web 19a.

Reference numeral 30 denotes a vehicle load weight detecting device, which is embedded in a wall inside the cargo bed 7 and is supplied with power from the battery 2. As shown in FIG. 5, on the front surface of the vehicle load weight detection device 30, a load weight display section 4 including a light emitting diode group of 7 segments for displaying the calculated load weight, for example.
1 and four front unbalanced load display lamps 42, rear unbalanced load display lamps 43, left unbalanced load display lamps 44, and right unbalanced load display lamps 45, which display the biased state of the load, and the calculated load weight is a predetermined maximum. An overload indicator lamp 46 for indicating that the loaded weight has been exceeded, an alarm buzzer 47 for notifying a biased load state and an overloaded state, and a clear switch 50 for setting an offset adjustment value are provided. Reference numeral 60 denotes a door switch, and the door switch 60 functions as an opening / closing detection means capable of detecting the opening / closing of the luggage carrier door 7a, and outputs a signal when the luggage carrier door 7a is opened. The sensing elements 21 and the door switch 60 are connected to the vehicle load weight detection device 30 by wiring or the like.

Next, the system configuration of the vehicle load weight detection device 30 will be described with reference to FIG. Reference numeral 31 denotes a central processing unit (CPU), and the CPU 31 performs various kinds of processing and control according to a predetermined program. Three
Reference numeral 2 denotes a read-only memory (ROM), and ROM3
2 stores programs for the CPU 31. Reference numeral 33 denotes a readable / writable memory (RAM), and the RAM 33 has a data area for storing various data generated during the processing of the CPU 31, a work area used for the processing, and the like.

Reference numeral 34 denotes a non-volatile memory (NVM),
The data stored in the NVM 34 is retained even when the power supply is cut off. In this NVM 34, the previous display load weight, which is the display value displayed on the load weight display unit 41 when the cargo door 7a is closed, and the offset adjustment and the characteristic correction value for the output pulse signal of each sensing element 21 are displayed. Each table, the offset correction value and the bias correction value table for the total value of the frequency of the output pulse signal of each sensing element 21 after the characteristic correction, the weight conversion formula, the overloaded weight value, and the four bias values of the front, rear, left, and right. The load judgment value is stored in advance. The NVM 34 functions as a storage unit that stores and holds the loaded weight that has been displayed on the display unit until the loading door 7a is closed.

Reference numeral 35 denotes an interface (I / F) section, and the interface section 35 is a sensing element I / F 35.
a, a display unit I / F 35b, an alarm unit I / F 35c, and a door switch I / F 35d. Sensing element I / F35
a is an exciting unit 35a1 that excites each sensing element 21 by supplying an exciting current to each sensing element 21.
A detection unit 35a2 that detects an AC voltage generated by the excitation of each sensing element 21 and converts the AC voltage into a DC voltage; and a VF that converts the converted DC voltage into a pulse signal having a frequency proportional to the voltage value and outputs the pulse signal to the CPU 31. Converter 35a
3 and 3.

Reference numeral 40 denotes a display unit, and the display unit 40
Is a loaded weight display section 41 that displays the loaded weight and functions as a display means, a front unbalanced load display lamp 42, a rear unbalanced load display lamp 43, and a left unbalanced load display lamp 4
4. It has a right-biased load display lamp 45 and an overload display lamp 46 indicating overload. Then, each of the display parts I
It is connected to the CPU 31 via / F35b. In addition, an alarm buzzer 47 for issuing an alarm when the load is biased or overloaded is operated by the alarm unit I / F 35c to indicate the open / closed state of the cargo door 7a by C.
The door switch 60 that outputs a signal for the PU 31 to recognize is connected to the CPU 31 via the door switch I / F 35d.

Reference numeral 36 denotes a power supply unit, and the power supply unit 36 is the vehicle 1
The electric power supplied from the battery 2 of the
1, front unbalanced load display lamp 42, rear unbalanced load display lamp 4
3, left unbalanced load display lamp 44, right unbalanced load display lamp 4
5, distributed to the overload indicator lamp 46, the alarm buzzer 47, the interface unit 35, etc., and supplied. 37 is RS-23
2C driver section is shown, and by providing this RS-232C driver section 37, it is possible to connect to an external device such as a handy terminal. Therefore, it is possible to set the overloaded weight and the like by communicating with the external device. it can. Therefore, it is not necessary to provide a key that is not normally used such as a bias correction value setting key and a numeric keypad as in the conventional vehicle load weight detection device, and therefore the vehicle load weight detection device 30
The configuration can be simplified.

Next, an embodiment of the memory map of the RAM 33 will be described with reference to FIG. In FIG. 7, RA
The M33 has a data area for storing various data and a work area used for various processing operations. Among these, in the work area, areas for calculation, total frequency register before bias correction, total frequency register, front-rear frequency ratio register, left-right frequency ratio register, and load weight register, and four front-back left-right bias flag areas, An overloaded flag area and the like are provided.

Next, the above-mentioned vehicle load weight detection device 3
Details of the processing performed by the CPU 31 configuring 0 will be described with reference to the flowcharts shown in FIGS. 8 and 9.

In FIG. 8, when the CPU 31 is operated by the supply of electric power from the battery 2 of the vehicle 1 in the standby state in which the number of clocks is reduced and the program starts, in step S1, an input signal from the door switch 60 causes a loading platform. It is determined whether the door 7a is opened. When it is determined that the loading door 7a is opened (Y in step S1), the process proceeds to step S2. On the other hand, the cargo door 7
If it is determined that a is not opened (step S1
N), and the step S1 is repeated to wait until the bed door 7a is opened. By this step S1, the cargo door 7
Until a is opened, the CPU 31 operates to save power.

When the loading door 7a is opened, the number of clocks of the CPU 31 is increased in step S2, and the power supply unit 3
CPU 6 is controlled to start the supply of operating power to the interface unit 35, the display unit 40, etc., so that the CPU startup process is executed, and then the process proceeds to step S3. That is,
CPU that was operating with low power consumption due to CPU startup processing
31 will operate normally. Further, by supplying operating power to the interface unit 35, the display unit 40, etc., the loaded weight can be calculated and the display unit 40 can be displayed. The loaded weight display unit 41 displays the loaded weight in which the previously displayed loaded weight is stored in the NVM 34. Further, as is clear from the description, this CPU activation process functions as the power supply control means.

In step S3, the clear switch 5
It is determined whether 0 has been pressed. If it is determined that the button has not been pressed (N in step S3), step S
Go to 5. On the other hand, when it is determined that the button is pressed (Y in step S3), the process proceeds to step S4, and the offset setting process is executed.

In the offset setting process, as shown in the flowchart of FIG. 10, in step S41, each sensing element 21 is sent via the sensing element I / F 35a.
The frequency indexing process is executed by indexing the frequency of the pulse signal input from, and the process proceeds to step S42. In step S42, the calculation of the frequency corresponding to the loaded weight by subtracting 200 Hz, which is the basic frequency when the loaded weight = 0 ton from the frequency of each sensing element 21 that has been calculated, in the calculation area of the RAM 33. Then, the frequency calculation process for the loaded weight is executed, and the process proceeds to step S43.

In step S43, the frequency values obtained by inverting the + and-signs of the calculated four frequencies are used as the offset adjustment value of each sensing element 21 in the NVM 34.
The offset adjustment value setting process is executed, and the process returns to the calling step S4. Then, returning to step S3, the clear switch 50 is checked again. By repeating step S3 in this way, the offset adjustment value can be set accurately.

In step S5, the sensing element I
The frequency indexing process is executed by indexing the frequency of the pulse signal input from each sensing element 21 via / F35a, and then the process proceeds to step S6.

In step S6, it is determined whether or not all the frequencies of the output pulse signals of the sensing elements 21 calculated in step S5 are within the specified range. Specifically, the offset can be adjusted by the offset adjustment value.
It is determined whether or not it is within the range of Hz to 700 Hz.
If even one of the sensing elements 21 determines that the frequency of its output pulse signal is outside the range of 30 Hz to 700 Hz (N in step S6), step S7.
Proceed to. In step S7, an error display process is executed by displaying an error in the loaded weight display unit 41, for example, by the letters "E.Lo" in the alphabet, and the process returns to step S3. On the other hand, if it is determined that all of the output pulse signals of each sensing element 21 are within the range of 30 Hz to 700 Hz (Y in step S6), step S8.
Proceed to.

In step S8, the offset adjustment processing is executed by offset-adjusting the frequency of the pulse signal input from each sensing element 21 calculated in step S5 in the calculation area of the RAM 33 with the offset adjustment value of the NVM 34. After that, the process proceeds to step S9.

In step S9, the pulse signal frequency from each sensing element 21 after the offset adjustment is set to R
The characteristic correction process is executed by correcting the characteristic with the characteristic correction value of the NVM 34 in the calculation area of the AM 33, and then the process proceeds to step S10.

In step S10, the total of the pulse signal frequencies from the respective sensing elements 21 after the offset adjustment and the characteristic correction, that is, the total frequency before the bias correction is calculated, and the total frequency register before the bias correction in the RAM 33 is calculated by this calculated value. By updating the storage value of the area, the pre-bias correction total frequency calculation process is executed, and then the process proceeds to step S11.

In step S11, among the frequencies of the output pulse signals of the respective sensing elements 21 after the offset adjustment and the characteristic correction, the total value of the frequency of the pulse signals output by the two front sensing elements 21 of the loading platform 7 is stored in the RAM.
The front and rear frequency ratio calculation processing is performed by dividing the front and rear frequency ratio by calculating the front and rear frequency ratio by dividing by the stored value in the pre-bias correction total frequency register area of 33. After that, the process proceeds to step S12.

In step S12, the sum of the frequencies of the pulse signals output from the two sensing elements 21 on the left side of the loading platform 7 among the frequencies of the output pulse signals of the respective sensing elements 21 after the offset adjustment and the characteristic correction is stored in the RAM.
The left / right frequency ratio calculation processing is performed by dividing the left / right frequency ratio register area of the RAM 33 by calculating the left / right frequency ratio by dividing by the stored value of the pre-bias correction total frequency register area of 33. After that, the process proceeds to step S13.

In step S13, the bias correction value to be applied to the calculation of the loaded weight is specified from the bias correction table of the NVM 34 using the stored values in the front-rear frequency ratio register area and the left-right frequency ratio register area as address pointers. Using this correction value, the stored value in the pre-bias correction total frequency register area is corrected in the calculation area of the RAM 33 to calculate the post-bias correction total frequency, whereby the post-bias correction total frequency calculation process is executed, and then step S14. Proceed to.

In step S14, the NV-corrected total frequency calculated in the calculation area of the RAM 33 is used as the NV
The loaded weight is calculated using the weight conversion formula of M34, and the stored value in the loaded weight register area of the RAM 33 is updated by this calculated value, whereby the loaded weight calculation process is executed, and then the process proceeds to step S15. Therefore, as is clear from the description, the loaded weight calculation process functions as the loaded weight calculation means.

In step S15, it is determined whether or not the stored value in the front-rear frequency ratio register area exceeds the front bias load determination value of the NVM 34. If it is determined that the number has exceeded (Y in step S15), the process proceeds to step S16,
In step S16, the flag F1 in the forward bias flag area of the RAM 33 is set to "1" to execute the forward bias flag setting process, and then the process proceeds to step S17. On the other hand, if it is determined that the number is not exceeded (N in step S15), the process proceeds to step S17.

In step S17, it is determined whether the stored value in the front-rear frequency ratio register area exceeds the rear unbalanced load determination value of the NVM 34. If it is determined that it has exceeded (Y in step S17), the process proceeds to step S18,
In step S18, the backward bias flag setting process is executed by setting the flag F2 of the backward bias flag area of the RAM 33 to "1", and then the process proceeds to step S19. On the other hand, if it is determined that the number is not exceeded (N in step S17), the process proceeds to step S19.

In step S19, it is determined whether or not the stored value in the left / right frequency ratio register area exceeds the left offset load determination value of the NVM 34. If it is determined that it has exceeded (Y in step S19), the process proceeds to step S20,
In step S20, the left bias flag setting process is executed by setting the flag F3 in the left bias flag area of the RAM 33 to "1", and then the process proceeds to step S21. On the other hand, if it is determined that the number is not exceeded (N in step S19), the process proceeds to step S21.

In step S21, it is determined whether or not the stored value in the left / right frequency ratio register area exceeds the rightward load determination value of the NVM 34. If it is determined that the number has exceeded (Y in step S21), the process proceeds to step S22,
In step S22, the flag F4 in the right-biased flag area of the RAM 33 is set to "1" to execute the right-biased flag setting process, and then the process proceeds to step S23. On the other hand, when it is determined that the number is not exceeded (N in step S21), the process proceeds to step S23.

In step S23, it is determined whether or not the stored value in the loaded weight register area exceeds the overloaded weight value of the NVM 34. When it is determined that the number is over (Y in step S23), the process proceeds to step S24, and in step S24, the flag F5 in the overload flag area of the RAM 33 is set to "1" to execute the overload flag setting process. , And then proceeds to step S25.
On the other hand, if it is determined that the number is not exceeded (step S
23), the process proceeds to step S25.

In step S25, the display of the loaded weight display section 41 is updated to the loaded weight stored in the loaded weight register area, whereby the display process is executed, and then the process proceeds to step S26. Therefore, the display value of the loaded weight display unit 41, which is a display unit, is updated by this display processing.

In step S26, the flag F in each of the front and rear, left and right biases in the RAM 33 and each flag area for overloading
By determining whether or not "1" is set in 1 to F5, the unbalanced load and the overload are determined. Flags F1 to F
"0" is set for all of 5, that is, unbalanced load,
If it is determined that it is not overloaded (N in step S26), the process proceeds to step S28.

On the other hand, if even one of the flags F1 to F5 is set to "1", that is, if it is determined that the load is unbalanced or overloaded (Y in step S26), the process proceeds to step S27. In step S27, among the front unbalanced load display lamp 42, the rear unbalanced load display lamp 43, the left unbalanced load display lamp 44, and the right unbalanced load display lamp 45, the display lamps corresponding to the flags F1 to F4 which are not “0” are turned on. If the flag F5 is set to "1", the overload indicator lamp 46 is also turned on and the alarm buzzer 47 is activated.
The alarm process is executed by ringing for a predetermined time, and then the process proceeds to step S28.

In step S28, the cargo door 7a is triggered by an input signal from the door switch 60 which is the opening / closing detecting means.
It is determined whether or not is closed. When it is determined that the cargo door 7a is closed (Y in step S28), the process proceeds to step S29. On the other hand, when it is determined that the luggage carrier door 7a is not closed (N in step S28), the process returns to step S3 and the series of processes from step S3 is repeated. As a result, while the loading platform door 7a is opened, the loading / unloading work is in progress, and the loaded weight that changes depending on the loading / unloading work can be displayed.

In step S29, the loaded weight displayed on the integrated weight display unit 41 is stored as the previously displayed loaded weight in the NVM 34, and the calculation of the RAM 33, the total frequency register before bias correction, the total frequency register, the front-rear frequency ratio register, The respective areas of the left / right frequency ratio register and the loaded weight register are cleared with initial values, and the four bias flag areas on the front, rear, left and right, and the flags F1 to F5 of the overloaded flag area are cleared with "0".

Then, the power supply unit 36 is controlled to stop the supply of the operating power supply to the interface unit 35, the display unit 40, etc., and the clock frequency of the CPU 31 is reduced to shift to the standby state. After that, the process returns to step S1 and the cargo door 7
Wait for a to open. As a result, the CPU 31 operates in a power saving mode until the loading door 7a is opened until the loading door 7a is opened. Further, as is clear from the description, this CPU standby shift processing functions as a power supply control means.

As is clear from the above description, in the vehicle load weight detecting device 30 installed on the inner surface of the luggage carrier 7 having the luggage carrier door 7a, the operator depending on loading / unloading work on the luggage carrier 7. When the platform door 7a is opened by the operation, the supply of operating power to the interface unit 35, the display unit 40, etc. is started, the loaded weight of the platform 7 is calculated by the loaded weight calculation means, and the calculated loaded weight is displayed by the display means. Is displayed on the loaded weight display section 41. When the loading door 7a is closed by the completion of the loading / unloading work, the supply of the operating power is stopped. Thus, when the loading platform door 7a is opened, it is considered that the loading / unloading work is being performed, and the operating power is supplied to the interface unit 35, the display unit 40, and the like only during the loading / unloading work. Only during the unloading work, the vehicle load weight detection device 30 can calculate and display the load weight.

As described above, in the vehicle load weight detecting apparatus 30 according to the present invention, the supply of the electric power to the interface section 35, the display section 40 and the like is automatically controlled according to the opening and closing of the luggage carrier door 7a. Therefore, in loading and unloading work, the operator only has to open the platform door 7a, which does not require the operation of the operation switch unlike the conventional vehicle load weight detection device. Therefore, the load weight is calculated. It is possible to solve the problem that the operation is troublesome and the operation is troublesome by the vehicle load weight detection device 30 according to the present invention.

Further, the electric power from the battery 2 is automatically supplied to the interface unit 35, the display unit 40, etc. only while the loading door 7a is opened, that is, during the loading / unloading work. Vehicle load detection device 3 according to the invention
The power consumption at 0 can be made lower than that of the conventional vehicle load weight device.

Further, the conventional vehicle load weight detecting device is
Although it was started in response to turning on the ignition switch or the like, the vehicle load weight detection device 30 according to the present invention calculates the load weight in accordance with the opening / closing of the luggage carrier door 7a, so that the switch operation of the ignition switch or the like is affected. It is possible to accurately calculate the loaded weight of the loading platform 7 without being performed.

Particularly, in the vehicle 1 having the box-shaped loading platform 7 for loading / unloading by opening the loading platform door 7a, when the vehicle loading weight detecting device 30 is installed in the driver's seat, loading / unloading is performed.
In order to confirm the loaded weight during the unloading work, the worker must interrupt the loading / unloading work and return to the driver's seat to check the loaded weight, but as in the present embodiment described above,
By installing the vehicle load weight detection device 30 on the inner surface of the loading platform 7, the operator can confirm the loading weight in the loading platform 7 during the loading / unloading work. Therefore, it is possible to prevent the operator from bothering to confirm the loaded weight during the loading / unloading work.

Further, in the vehicle load weight detection device 30, the load weight that has been displayed on the load weight display section 41 until then when the loading door 7a is closed is a storage means.
34 is stored and held, the accurate loaded weight of the loading platform 7 stored in the NVM 34 is displayed on the loaded weight display unit 41 immediately after the loading platform door 7a is opened.

In the above-described embodiment, the cargo bed 7
Although the vehicle load weight detection device 30 installed on the inner surface of the vehicle has been described, the present invention is not limited to this, and other embodiments such as installing the vehicle load weight detection device 30 in the driver's seat will be described. You can also do it.

Further, although the vehicle 1 having the box-shaped luggage carrier 7 has been described in the above-described embodiment, the invention is not limited to this, and the door, shutter, etc. of the luggage carrier 7 are opened to load the cargo. The vehicle 1 for loading and unloading work may have various different embodiments such as a vehicle in which the upper part of the loading platform 7 is opened and the upper part is covered with a cover.

Further, in the above-described embodiment, the vehicle load weight detection device 30 displays the calculated load weight on the load weight display section 41, and when the load weight is overloaded or unbalanced, a lamp is displayed. Although an alarm is issued by a buzzer or the like, the present invention is not limited to this, and the calculated load weight may be stored, displayed, alarmed, or the like depending on the operation mode load. There may be various different embodiments.

[0062]

As described above, according to the vehicle load weight detecting apparatus of the present invention described in claim 1, it is necessary to calculate the load weight only when the opening / closing means detects that the door of the bed is opened. By causing the sensor and the load weight calculation means to supply operating power, the load weight of the load platform is calculated based on the signal output from the sensor provided in the vehicle only when the door of the load platform is opened. . Therefore, the loaded weight of the loading platform is automatically calculated according to the opening of the loading platform door. Moreover, since the operating power is supplied to the sensor and the load weight calculation means only when the luggage door is opened, the power consumption of the vehicle load weight detection device can be minimized. Therefore, even if the operating power is supplied from the battery, it is possible to prevent the occurrence of a situation in which the battery goes down and the engine cannot be started.

According to the vehicle load weight detection apparatus of the present invention described in claim 2, in addition to the effect of the invention of claim 1, display means for displaying the load weight calculated by the load weight calculation means is provided. Even if the power supply control means is further provided, the operating power supply of the display means is supplied only when the opening / closing detection means detects the opening of the door of the loading platform. Power consumption can be minimized.

According to the vehicle load weight detecting apparatus of the present invention described in claim 3, in addition to the effect of the invention of claim 2, when the door of the cargo bed is closed, the display means is displayed until then. By further comprising storage means for storing and holding the loaded weight, which is displayed when the loading door stored in the storage means is closed immediately after the opening / closing detection means detects the opening of the loading door. Since the loaded weight thus displayed can be displayed on the display means, the loaded weight can be accurately displayed immediately after the display means starts displaying.

According to the vehicle load weight detecting apparatus of the present invention described in claim 4, in addition to the effect of the invention described in claim 2 or 3, the display means is visually recognized when the door of the luggage carrier is opened. By installing it on the inner wall surface of the loading platform as much as possible, it is possible for the operator to confirm the loaded weight in the loading platform during loading / unloading work. Therefore, the worker can carry out the loading / unloading work while confirming the loaded weight of the loading platform, so that the working efficiency can be improved.

[Brief description of drawings]

FIG. 1 is a diagram showing a basic configuration of a vehicle weight detection device according to the present invention.

FIG. 2 is a diagram showing a vehicle in which a vehicle load weight detection device according to an embodiment of the present invention is arranged, FIG.
(B) is a plan view.

FIG. 3 is an exploded perspective view of a structure for supporting the leaf spring of FIG. 2 on a luggage carrier frame of a vehicle.

FIG. 4 is a sectional view showing a sensing element provided in the shackle pin of FIG.

FIG. 5 is a front view of the vehicle load weight detection device according to the embodiment of the present invention.

6 is a system configuration diagram of the vehicle load weight detection device in FIG.

FIG. 7 is a diagram showing a memory map of the RAM in FIG.

FIG. 8 is a flowchart showing a part of the processing performed by the CPU in FIG.

9 is a flowchart showing another part of the processing performed by the CPU in FIG.

10 is a flowchart showing an offset setting process performed by the CPU in FIG.

[Explanation of symbols]

7a luggage carrier door 21 Sensor (sensing element) 30 Vehicle load detection device 31a Loaded weight calculation means (CPU) 31b Power supply control means (CPU) 34 Storage Means (NVM) 41 Display means (loading weight display section) 60 Open / close detection means (door switch)

─────────────────────────────────────────────────── --Continued from the front page (56) References JP-A-1-197615 (JP, A) JP-A-1-197616 (JP, A) JP-A-9-113342 (JP, A) JP-A-8- 50054 (JP, A) Actual development Sho 56-19726 (JP, U) Actual development Sho 58-4035 (JP, U) Patent 3314263 (JP, B2) (58) Fields investigated (Int.Cl. ⁷ , DB name) ) G01G 19 / 02,19 / 08,19 / 12 G01G 23/00 B60P 5/00

Claims (4)

(57) [Claims] 1. A sensor mounted on a vehicle for generating a signal that changes according to a load applied to a bed of the vehicle,
A loading weight detection device for a vehicle, comprising: a loading weight calculation means for calculating and detecting a loading weight of a loading platform of the vehicle based on a signal generated by the sensor; and an opening / closing detection means for detecting opening / closing of a door of the loading platform. A power supply control means for controlling the sensor and the load weight calculation means to supply operation power only when the opening / closing detection means detects the opening of the door of the cargo bed. Loading weight detection device. 2. A display means for displaying the loaded weight calculated by the loaded weight calculating means is further provided, and the sensor and the sensor are provided only when the opening / closing detecting means detects the opening of the door of the loading platform. The vehicle load weight detection device according to claim 1, wherein the load power calculation unit is supplied with an operation power supply and the display unit is supplied with an operation power supply. 3. When the door of the loading platform is closed, the storage means further stores and holds the loaded weight that has been displayed on the display means until then, and the display means includes the opening / closing detection means. 3. The vehicle load weight detection device according to claim 2, wherein the load weight stored in the storage unit is displayed immediately after the opening of the door of the loading platform is detected. 4. The vehicle according to claim 2 or 3, wherein the display means is installed on a wall surface inside the cargo bed that is visible when the door of the cargo bed is opened. Load weight detection device.