JPH0216270Y2 - - Google Patents

Description

[Detailed explanation of the idea] The present invention relates to a belt scale totalizer.

Conventionally, this type of totalizer, as shown in FIG. 1, detects the instantaneous weight applied to a certain section of a weighing conveyor 2 carrying an object to be weighed 1 using a pressure sensor 3 such as a load cell, and converts the load to a voltage converter. At the same time, an analog signal (voltage or current) proportional to the instantaneous weight outputted from weighing conveyor 2 is received.
The pulse signal output from the pulse generator 5 according to the amount of belt movement is received, and the instantaneous conveyance amount is determined by a multiplication circuit 6 using an analog switch, and the multiplication result as the instantaneous conveyance amount is as follows.
It becomes a pulse signal with a constant time width and different heights. After smoothing with a built-in integration circuit, it is input to the V/F conversion circuit 7 which converts it into a pulse signal with a frequency proportional to the analog voltage, and this pulse is converted into a pulse. The integrated value is obtained by counting in the circuit 8.

In order to obtain a highly accurate integrated value, zero point adjustment is performed using zero point calibration data, and span adjustment is also performed as needed using span calibration data. The zero point calibration data is provided, for example, to the instantaneous weight value input circuit 9, and the span calibration data is provided to the span set circuit 10 for adjustment.

Incidentally, the zero point calibration data or span calibration data is obtained by actually operating the weighing conveyor 2, but reference data is set in the totalizer in advance prior to the operation for this calibration. That is, the belt total length pulse number obtained from the belt rotation speed and the belt rotation speed pulse number for stopping the calibration operation,
The two standard data are the standard instantaneous weight determined by the test chain or test weight, and the standard integrated value obtained from the belt circumference length and belt rotation speed.

However, conventionally, each of these reference data has been calculated manually based on the specifications of the weighing conveyor 2 and the pulse generator 5. This is preferred because it allows the reference data to be set directly and makes the totalizer versatile for various types of weighing conveyors and pulse generators. However, there is a drawback that if one parameter is changed, complicated manual calculations are required again.
Furthermore, cumbersome operations such as resetting data are required.

The present invention was created in view of this problem, and aims to make it possible to easily and automatically set reference data for obtaining calibration data for zero point adjustment, span adjustment, etc. while maintaining versatility. , a digital signal obtained by digitally converting an analog signal that is output in proportion to the instantaneous weight applied to a certain section of the weighing conveyor that conveys the object to be weighed, and a pulse that is generated according to the amount of belt movement of the weighing conveyor. A signal setting means for setting the total number of pulse signals during one rotation of the belt in a totalizer of a belt scale that receives a signal and totals the total weight of the conveyed object to be weighed; A belt rotation speed setting means for setting the rotation speed, a circumference setting means for setting the length of one circumference of the belt, a reference weight setting means for setting a reference weight per unit length, and a weighing mode and zero point adjustment. mode selection means for selecting one of the mode and span adjustment mode, and when the zero point adjustment mode is selected, the belt scale is run idly and the belt rotation speed is set by the belt rotation speed setting means. a zero point adjustment means for determining a zero point error based on the setting data of the signal number setting means and the belt rotation speed setting means from the cumulative load while the belt is rotated, and storing this zero point error in a first memory; and a span adjustment. When the mode is selected, the belt is operated with a reference weight placed on the belt, and the cumulative load and the above-mentioned circumference are calculated while the belt is rotated by the number of belt rotations set by the belt rotation speed setting means. span adjusting means for determining a span factor and storing it in a second memory based on the data respectively set in the length setting means and the reference weight setting means, and when the weighing mode is selected, the first , a totalizer for a belt scale equipped with a reference data setting device, characterized in that the total weight of the object to be weighed is integrated while performing zero point adjustment and span adjustment using data stored in a second memory. This is what we provide.

Hereinafter, the present invention will be explained in detail with reference to embodiments shown in the accompanying drawings, and the explanation will be based on an embodiment in which the setting device and calculation means in the configuration of the above-mentioned invention are more familiar to each other. That is, FIG. 2 is a block diagram of an embodiment, which is an improved version of the totalizer main body shown in FIG. First, we will explain the background of the totalizer itself.

The circuit elements constituting the totalizer in Fig. 1, such as the multiplier circuit 6, V/F conversion circuit 7, instantaneous weight value input circuit 9, and span set circuit 10, are mainly analog-processed, so they cannot be easily processed under external environmental conditions, especially temperature changes. This causes a drift in the voltage and current, resulting in an error in the instantaneous weight.In addition, the current supplied to the power supply circuit 9 is usually shared with other devices in the environment where the belt scale device is installed. in,
There are also fluctuations in the voltage supplied from the power supply circuit 11 to each circuit, which causes an error in the instantaneous weight, which can result in a considerable error in the integrated value obtained by the counter circuit 8. In order to accurately weigh, it is better to increase the number of divisions to reduce the weight value per unit pulse, that is, increase the number of pulses generated in the V/F conversion circuit 7 based on the output of the scaler circuit 12. Each time a change is made, the pulse height must be corrected according to the weight unit, and there is also the problem that the precision of this delicate correction directly affects the integrated value.

As described above, the totalizer illustrated in FIG. 1 has many drawbacks due to analog processing and problems in aiming for higher accuracy. Therefore, the inventor of the present invention conducted repeated research and attempted to switch from the conventional circuit system centered on analog processing to a circuit system centered on digital processing. We have created a totalizer for belt scales that instantly calculates the integrated value using a calculation circuit, so that the integrated value is unaffected by external conditions and allows highly accurate weighing. Its configuration consists of an analog-to-digital conversion circuit that converts an analog signal, which is output in proportion to the instantaneous weight applied over a certain section of the weighing conveyor carrying the object to be weighed, into a digital signal, and an output from this analog-to-digital conversion circuit. a multiplier circuit that multiplies the maximum capacity (scale) data of the flow rate set in advance; a weighting circuit that assigns predetermined weight data to the output of this multiplier circuit; The present invention is characterized by comprising an accumulation circuit that accumulates the outputs of the weighting circuit using the generated pulse signal as a starting signal.

An embodiment of the present invention will be described with reference to the totalizer as a background, and its overall configuration including the integrated meter.

In FIG. 2, the totalizer 20 of one embodiment includes:
The input terminal 21 includes an instantaneous weight input terminal 21 and a belt movement pulse input terminal 22, and the input terminal 21 receives and inputs an analog signal (for example, a voltage signal) proportional to the instantaneous weight applied over a certain section of the weighing conveyor that conveys the object to be weighed. Terminal 22 receives a pulse signal generated in response to the amount of belt movement of the weighing conveyor.

23 converts the analog signal from the instantaneous weight input terminal 21 into a digital signal (for example, a binary code signal).
analog-to-digital conversion circuit for converting into
is a multiplier circuit that multiplies the digital signal from the analog-to-digital conversion circuit 23 by the maximum capacity data of the flow rate set in the scale factor setting device 25, which consists of a switch, and the scale factor is the scale factor in this example. Capacity per hour (t/h
or Kg/h).

26 is a weighting circuit that applies a predetermined weight w to the output of the multiplication circuit 24 to facilitate subsequent calculations; in this example, the multiplication circuit 24
This is a division circuit that divides the output of by a constant K.
Therefore, the constant K corresponds to w=1/K in relation to the weight w.

Reference numeral 27 denotes an accumulation circuit that accumulates the output of the weighting circuit 26 using the pulse signal P1 as a starting signal, and the pulse signal P1 is a pulse signal received at the belt movement amount pulse input terminal 22. Reference numeral 28 is a display circuit that converts the accumulation result (binary code format) of the accumulation circuit 27 into a decimal number and displays the total weight of the objects to be weighed conveyed by the conveyor.

Note that 29 and 30 are both circuits for correcting digital signals from the analog-digital conversion circuit 23, and the arithmetic circuit 29 is for adjusting the zero point of the instantaneous weight measured using zero point data stored in advance in the memory 31. , the arithmetic circuit 30 is for adjusting the instantaneous weight span using span data stored in advance in the memory 32, and the details thereof will be described later. Further, the switch 33 with three outputs and three terminals is a switch for mode change, and is switched to terminal M in the normal integration mode, switched to terminal Z in the zero point adjustment mode, and switched to terminal S in the span adjustment mode.

The basic integration operation of this integration meter will be explained using a specific example.

On the front bank, the belt length of the weighing conveyor is 10 m, the belt speed is 10 m/min, and the pulse signal is generated over the entire belt length.
It is assumed that 6000 are generated, and the zero point adjustment memory 31
is set to 2,500, and a span factor of 10,000 (reference value) is set to the span adjustment memory 32.
Further, the maximum capacity of the scale is set to 36 t/h, the scale factor setter 25 is set to 36, and the value of K of the weighting circuit 26 is preselected to 3,600,000.

The analog-digital conversion circuit 23 outputs 2500 when the instantaneous weight is zero, and outputs 12500 when the instantaneous weight is maximum (both are binary codes, but for simplicity they are shown in decimal format). Subtract 2500 from this output signal and the output range is from 0 to
It becomes 10000. The span factor is 10,000, and the output of the arithmetic circuit 30 as a multiplication circuit is 0 to 10,000.
The output signal in this range is input to the multiplication circuit 24.

The multiplier circuit 24 multiplies the output of the arithmetic circuit 30 by 36, and the output range becomes 0 to 360000, and K is
The output of the weighting circuit 26 selected as 3600000 is 0~
360000/3600000 becomes 0 to 0.1.

Now, assuming that the belt is being conveyed with the maximum instantaneous weight and the maximum belt speed, 100 movement pulse signals per unit length of the belt are output per second, received by the input terminal 22, and switched to the M of the changeover switch 33. It is input to the accumulation circuit 27 via the terminal. The weighting circuit 26 outputs 0.1, and each time the pulse signal P1 is input to the accumulation circuit 27, that 0.1 is added to the previous accumulated value. 100 pulses/second in 1 hour
0.1 will be accumulated 360000 times from 3600 seconds,
The cumulative result is 36,000, and the display circuit 28 displays the conveyance amount of 36,000 kg (36 tons).

In the above embodiment, since one accumulation takes 1/100 seconds, the accumulation can be accomplished almost instantaneously, and in addition, the processing time of the accumulation circuit 27 is
If the value of the weight w (=1/K) in 6 is made sufficiently small (increasing the number of divisions, that is, reducing the instantaneous weight per pulse signal), it is possible to greatly increase the integration accuracy according to this small value. can.

Next, the zero point adjustment device will be explained.

The zero point adjustment device uses an analog-to-digital conversion circuit 23 when an error occurs in the zero point of the scale due to the instantaneous weight detection unit or the attachment of the object to be measured to the belt.
The output is not the correct measured value and if it is integrated as it is, an error will occur in the integrated value.This device is provided to prevent this.The zero point adjustment device described below uses a separate circuit means to adjust the zero point It does not take the form of obtaining data, and is built into the totalizer of this embodiment in a relatively simple form, and is equipped with an accumulating circuit 39 similar to the accumulating circuit 27 according to the above embodiment to perform zero point adjustment (hereinafter referred to as "zero point adjustment"). The aim is to obtain high-precision data (sometimes referred to as "key").

This zero point adjustment device includes three means, one of which is a belt pulse setter 61 that sets the number of pulses per rotation of the belt, and a belt rotation speed setter that sets an integer value for the number of rotations of the belt. 62 and
A pulse number calculating circuit 35 multiplies the outputs of these setting devices 61 and 62 to calculate the number of pulse signals that can be transmitted for the calibrated belt length, and a pulse number calculation circuit 35 is activated by turning on the calibration push button 36 and is input to the terminal 22. a gate circuit 37 that controls the passage of pulse signals, and a counter 3 that counts the pulse signals from the gate circuit.
8, and a comparison circuit 40 which compares the output of the counter 38 and the output of the pulse number calculating circuit 35 and, if they match, provides a monitoring completion signal to the gate circuit 37. The second means includes an accumulation circuit 39 that accumulates the output of the analog-to-digital converter circuit 23 using the pulse signal as a starting signal until the monitoring completion signal is output; Accumulation circuit 39
The accumulation (integration) result is sent to the pulse number calculation circuit 35.
This is a zero-point weight calculation means that calculates the zero-point weight per one pulse signal. The third means is the division circuit 41
The zero point adjustment means is comprised of a memory 31 for storing data of the zero point weight per pulse signal obtained in the above, and a subtraction circuit 29 for subtracting the zero point weight from the instantaneous weight output from the analog-to-digital conversion circuit 23.

The function is to set the weighing conveyor to run empty, set the belt rotation speed (integer) for zero adjustment in the belt rotation speed setting device 62, and set the number of emitted pulses for one rotation of the belt to the belt rotation speed setting device 62. Set it on the pulse setter 61. Once the data is set, the arithmetic circuit 35 calculates the number of pulses corresponding to the belt length targeted for zero adjustment. Switch to the mode selector switch 33 and the Z terminal side and press the calibration push button 36.
When turned on, the gate circuit 37 opens, and the counter 38 counts the pulse signals per unit length of belt movement input to the pulse input terminal 22.
At the same time, the pulse signal that has passed through the gate circuit 37 is given to the accumulation circuit 39 via the Z terminal of the third-stage mode changeover switch 33-3, and is passed from the analog-digital conversion circuit 23 to the first-stage switch 33.
The instantaneous empty weight input to the accumulating circuit 39 via the -1 Z terminal is accumulated.

The contents of the counter 38 are compared point by point with the output of the arithmetic circuit 35 in a comparator circuit 40, and when they match, a match signal is output from the comparator circuit 40 to the gate circuit 37, and the gate circuit 37 is closed. counter 3
The counting of 8 and the processing of the accumulation circuit 39 are stopped. In the accumulating circuit 39, an integrated value is created of the instantaneous weight zero point output corresponding to the number of pulse signals corresponding to the set belt length. This integrated value is divided by the circuit 4
1 by the output of the arithmetic circuit 35 (the number of pulse signals corresponding to the belt length), the zero point output per pulse signal is obtained. This zero point output value is displayed on the display 42, and manual zero adjustment (Manual;
ML), it becomes a zero factor index, which is read and set in a zero factor setter 43 consisting of a switch, and then provided to the memory 31 via a zero adjustment switch 44. In the case of automatic zero adjustment (Auto; A), the output of the divider circuit 41 is transferred to the memory 3 via the A terminal of the zero adjustment switch 44.
1 is directly rewritten and used as the zero point data for the subsequent integration process.

To give a concrete example, the number of pulses per revolution of the belt is
6000, if the zero adjustment is done with 3 rotations of the belt, set 6000 to the belt pulse setter 33, then set the belt rotation speed setter 3 to 6000.
Set 3 to 4. The output of the arithmetic circuit 35 is 18000
Therefore, when the mode changeover switch 33 is switched to the Z terminal side and the calibration push button 36 is turned on, the gate circuit 3
7 opens and the counter 38 starts counting. At the same time, the accumulation circuit 39 converts the analog-to-digital converter 2
Accumulate the output of step 3 (of course, the accumulated contents are cleared before starting the accumulation). counter 38
When the number reaches 18000, the gate circuit 37 is closed and counting and accumulation are stopped. If the content of the accumulator circuit 39 at this time is 45018000, the arithmetic circuit 41 is
Execute 45018000/18000 and output 2501. By storing this zero point data 2501 in the memory 31, accurate instantaneous weight can be obtained by subtracting the memory contents 2501 from the output from the analog-to-digital conversion circuit 23 in the subtraction circuit 29 when in the integration mode (M). That is.

Note that here, the correct zero point output from the analog-digital conversion circuit 23 is set to 2500,
Even when the zero point output is determined to be 0, a similar zero adjustment can be performed by operating the accumulation circuit 39 and the arithmetic circuit 41 including the positive and negative signs.

Next, we will explain the span adjustment device.The span adjustment device uses an analog-to-digital conversion circuit 2 when an error occurs in the span of the instantaneous weight detection section.
If the output of step 3 does not become the predetermined correct measured value and is integrated as it is, an error will occur in the integrated value, so this is provided to prevent this.The span adjustment device described below is a separate unit. The data of the span factor to be corrected is not determined by the circuit means of the present invention, but is built into the totalizer of this embodiment in a relatively simple form, and the accumulation circuit 27 is similar to the accumulation circuit 27 of the previous embodiment. A circuit 50 is provided so that correction data for span adjustment can be obtained with high precision.

This span adjustment device includes a belt movement amount monitoring means, a standard integrated value calculation means for calculating an integrated value as a reference for calibration, a span factor calculating means for calculating a new span factor, and a span factor adjustment for multiplying the instantaneous weight by a new span factor. It consists of means.

The belt movement amount monitoring means includes a belt pulse setting device 61 for setting the number of pulses per rotation of the belt, a belt rotation speed setting device 62 for setting an integer value for the number of rotations of the belt, and outputs of both of these setting devices 33 and 34. A pulse number calculation circuit 35 calculates the number of pulse signals that can be transmitted for the calibrated belt length by multiplying a gate circuit 37; a counter 38 that counts pulse signals from the gate circuit; and a comparison circuit 40 that compares the output of the counter 38 with the output of the pulse number calculation circuit 35 and provides a monitoring completion signal to the gate circuit 37 when they match. Equipped with

The reference integrated value calculation means includes a reference weight setter 45 for setting a reference weight for calibration, a belt circumference setter 46 for setting the length of one circumference of the belt, and outputs of both of these setters 45 and 46. A belt one-round integrated value calculation circuit 47 that multiplies to obtain an integrated value for one rotation of the belt, and a reference integrated value to be calibrated using the output of this calculation circuit 47 and the integer rotation speed data from the belt rotation speed setting device 34. and a reference integrated value calculation circuit 48 for calculating the value.

The span factor calculation means includes an accumulation circuit 50 that accumulates the output from the analog-to-digital conversion circuit 23 using the pulse signal as a starting signal until a monitoring completion signal is output in the belt movement amount monitoring means; and a division circuit 49 that divides the accumulation (accumulation) result of the accumulation circuit 50 by the output of the reference accumulation value calculation circuit 48 at the time when the accumulation circuit 50 is output.

The span factor adjustment means is the division circuit 49.
A memory 32 that stores the span factor determined by
and a multiplication circuit 30 that multiplies the instantaneous weight from the analog-to-digital conversion circuit 23 by a span factor.

Therefore, when the belt rotation speed for performing span adjustment is set in the belt rotation speed setting device 62 and the number of emitted pulses for one revolution of the belt is set in the belt pulse setting device 62, the arithmetic circuit 35 adjusts the span. The total number of pulses corresponding to the target belt length is calculated. On the other hand, in order to set the reference instantaneous weight in advance, place the test chain on the belt or add the instantaneous weight directly to the instantaneous weight detection part with a test weight, and set the reference instantaneous weight obtained by this. At the same time, set the length of one circumference of the belt in the belt circumference setting device 45.
Set to 6. After each data is set, the arithmetic circuit 47 multiplies the reference instantaneous weight data and one belt circumference data to obtain an integrated value of one belt circumference. In the next arithmetic circuit 48, this integrated value is multiplied by the belt rotation speed data from the belt rotation speed setting device 34. This multiplication result becomes a reference integrated value for span adjustment and is applied to the span factor calculation circuit 49.

Switch the mode selector switch 33 to the S terminal side,
When the calibration push button 36 is turned on, the gate circuit 37 is opened, and the pulse signal of the belt movement amount input to the pulse input terminal 22 is counted by the counter 38. At the same time, the pulse signal passing through the gate circuit 37 is transferred to the third stage mode changeover switch 33-3.
is applied to an accumulation circuit 50 through the S terminal of the weighting circuit 26 to accumulate the reference instantaneous weight from the weighting circuit 26.

The contents of the counter 38 are compared point by point with the output of the arithmetic circuit 35 in a comparator circuit 40, and when they match, a match signal is output from the comparator circuit 40 to the gate circuit 37, and the gate circuit 37 is closed. counter 3
The counting of 8 and the processing of the accumulation circuit 50 are stopped. The accumulator circuit 50 includes a span factor at the time of calibration.
An integrated value influenced by SP (set in memory 32) is created. This integrated value can also be displayed on the display circuit 28 via a gate circuit 51 that allows this data to pass when the SWI is in the span mode.

The integrated value SWI of the accumulating circuit 50 is determined by the integrated value SWI in the arithmetic circuit 49 based on the reference integrated value WST from the arithmetic circuit 48 and the spenfactor SP during calibration.
A WST/SWI calculation is performed and a new span factor is calculated. The calculation result is displayed on the display circuit 42. When performing manual span adjustment, the displayed content becomes an index of the span factor and is set in the span factor setting device 52, which is composed of a switch, and the span factor is set in the memory 3 via the span changeover switch 53.
given to 2. When automatically setting the span adjustment data, the output of the arithmetic circuit 49 is directly rewritten in the memory 32 to new span data via the A terminal of the span changeover switch 53.

To give a concrete example, the number of pulses per revolution of the belt is
6000, the span shall be adjusted by three rotations of the belt,
One circumference of the belt is 10m, the reference instantaneous weight is 60Kg/m,
The scale capacity is 36t/h. Set the belt pulse setter 61 to 6000, the belt rotation speed setter 62 to 3, the belt 1 circumference setter 46 to 10, and the reference weight setter 45 to 60. The memory 32 is set to 1.0.

The output of the arithmetic circuit 35 is 6000×3=18000.
On the other hand, the output of the arithmetic circuit 47 is 60×10=600,
The output of the calculation circuit 48 is 600 x 3 = 1800 (Kg) (belt pulse 100Hz, output of the calculation circuit 35 is 18000)
18000/100 x 60 = 3 (minutes) (standard integrated value for 3 minutes for a capacity of 36t/h).

Set the mode selector switch 33 to S and press the calibration push button 3.
6, the gate circuit 37 opens, the counter 38 starts counting, and at the same time the accumulating circuit 50 accumulates the instantaneous weight (of course, the previous contents are cleared before accumulating). When the counter 38 reaches 18000, the gate circuit 37 closes and stops calculation and accumulation, and if the content of the accumulation circuit 50 at this time is 1800, the arithmetic circuit
49 outputs 1.0 from 1.0×1800/1800, but if the content is 1900, it outputs 1.0 from 1.0×1800/1900.
0.9473... is output, and subsequent span adjustment is performed by storing this value in the memory 32.

In the embodiment shown in FIG. 2 above, a certain block has been explained as hardware such as a functional circuit for arithmetic operations and accumulation. Of course, it is also possible to replace it with computer software (program). Although the disclosure of a specific program will be omitted, this type of program can be constructed relatively easily by those skilled in the art based on the disclosure of the present invention.

Furthermore, regarding the above embodiment, in the output signal of the analog-to-digital conversion circuit 23, the previous output value is stored and compared with the current output value, and when the difference is greater than a predetermined value (the fluctuation is (when the difference is too large), a circuit for issuing a warning or a circuit for correction may be provided depending on the difference. As the correction circuit, an interpolation calculation circuit is provided, for example, a circuit that calculates (previous output value + current output value)/2 and outputs the calculation result to the multiplication circuit 24 side of maximum capacity data.

As explained in detail above, according to the present invention,
Belt pulse setting device 61, belt rotation speed setting device 6
2. Calculating means 35, 4 which independently provide the belt 1 circumference setting device 46 and the reference weight setting device 47 and internally process the reference data set in each setting device.
7 and 48, it is possible to easily and automatically set reference data while maintaining versatility.

[Brief explanation of the drawing]

FIG. 1 is a block diagram for explaining a conventional totalizer, and FIG. 2 is a block diagram showing an embodiment of the present invention. 1...Object to be weighed, 2...Weighing conveyor, 4...
Load-voltage converter, 5...Pulse generator, 6
1...Setter for the number of pulse signals per revolution of the belt, 62
. . . Belt rotation speed setting device, 45 . . . Belt rotation length setting device, 46 .

Claims (1)

[Scope of claim for utility model registration] A digital signal obtained by digitally converting an analog signal output in proportion to the instantaneous weight applied over a certain section of a weighing conveyor that conveys objects to be weighed, and the amount of belt movement of the weighing conveyor. A signal setting means for setting the total number of pulse signals during one rotation of the belt in a totalizer of a belt scale that receives a pulse signal generated in response to a pulse signal and totalizes the total weight of the conveyed object to be weighed. , a belt rotation speed setting means for setting the rotation speed of the belt during adjustment, a circumference setting means for setting the length of one circumference of the belt, and a reference weight setting means for setting a reference weight per unit length. and a mode selection means for selecting one of the weighing mode, the zero point adjustment mode, and the span adjustment mode, and when the zero point adjustment mode is selected, the belt scale is run idly and the belt rotation speed setting means A zero point error is determined from the cumulative load while the belt is rotated by a set number of belt rotations based on the setting data of the signal number setting means and the belt rotation number setting means, and this zero point error is stored in a first memory. When the zero point adjustment means and the span adjustment mode are selected, the belt is operated with a reference weight placed on the belt, and the belt is rotated by the belt rotation speed set by the belt rotation speed setting means. and a span adjustment means for determining a span factor and storing it in a second memory based on the cumulative load of the meter and the data set in the circumference setting means and the reference weight setting means, respectively, and the measuring mode is selected. The reference data setting device is characterized in that, when weighing, the data stored in the first and second memories are used to perform zero point adjustment and span adjustment, and to integrate the total weight of the object to be weighed. Equipped with a totalizer for belt scale.