JPH0226732B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a weight measuring method applied to, for example, electronic toll scales.

In conventional electronic toll scales, data from a weight detection unit that outputs the weight of the object to be weighed as a digital quantity is sequentially stored in a register, and the latest plural pieces of data, for example, eight pieces of data, M ₁ to M are stored in this register. ₈
Count the number of data n ₁ , n ₂ , n ₃ that match data M ₁ , M ₂ , _{M 3} respectively in Then, when n ₁ ≧ 5, the display is updated with the data M ₁ of n ₁ as new measurement data, while when n ₁ < 5, the difference between data M ₁ and the previous measurement data M is
If it is within a certain set value, the previous measurement data M is left as is, and if it is larger than a certain setting value, the display is updated using data _M1 as new measurement data.

However, with this method, for example, when an object is placed on a weighing pan, the values when the weight changes are displayed sequentially, making it difficult for the operator to continue reading weight and other values from the display. The display was not only difficult to read, but also caused a feeling of fatigue. In particular, with scales that light up lamps corresponding to weight categories, the lamps in the middle blink in sequence, making the user feel even more fatigued.

SUMMARY OF THE INVENTION An object of the present invention is to solve the conventional drawbacks by displaying only values in a stable state or a quasi-stable state before and after the stable state, without displaying values during weight fluctuations.

An electronic toll scale will be described below as an embodiment of the present invention. Figure 2 shows the overall circuit configuration of the electronic toll scale. In the figure, reference numeral 1 denotes a weight detection section that detects the weight of the object to be weighed as an analog quantity and then converts it into a digital quantity, and is composed of a weight sensor 2, a differential amplifier 3, a low-pass filter 4, and an A-D converter 5. ing. As the weight sensor 2, for example, an electrical resistance wire type load cell is used which detects, as an analog voltage signal, mechanical strain generated in proportion to the weight of an object to be weighed when it is placed on a weighing pan. The differential amplifier 3 amplifies the analog voltage signal detected by the weight sensor 2, and the low-pass filter 4 amplifies relatively high-frequency vibrations and noise from the applied signal.
It is given to the A-D converter 5. The A-D converter 5 samples the analog voltage signal that has passed through the low-pass filter 4 at approximately regular intervals, converts the analog signal into a digital signal, and then outputs the signal to the I/O port 6.
It is given to the data processing section 7 through.

The data processing section 7 includes a central processing unit CPU8, a read-only memory ROM9, and a random access memory RAM10. Said CPU
8 performs flicker prevention processing on the weight data given from the weight detection unit 1 according to the processing means described below, and then performs arithmetic processing based on the data input from the keyboard 12 connected via the keyboard display controller 11. At the same time, these data are digitally displayed on the display 13. Also, the above
The ROM 9 stores a program for controlling the above-described operations of the CPU 8. Furthermore, the above
RAM10 has registers as shown in Figure 2.
REG ₀ ~ _{REG 5} , REG ₁₀ , Accumulator ACC
and counters C ₁ to _{C 3} are assigned to predetermined addresses.

Here, the input data input from the weight detection section 1 is transferred to the registers REG ₀ to REG ₅ , and the weighing data obtained by the flicker prevention process described later is transferred and stored in the register REG ₁₀ . . Further, the difference between the measurement data stored in the register REG ₁₀ and the data in the register REG ₀ is transferred and stored in the accumulator ACC. Furthermore, the counter _C1 has the register
_{The counter C2 indicates the} number of data that matches _{the data in register REG 0 among the data transferred to REG 0 to REG 5} . The counter REG ₅ stores the number of data that matches the data of , and the number of times of processing that has been carried out thereafter in the flowchart of FIG. 4, which will be described later.

Now, let's move on to the third data processing method for this device as a whole.
This will be explained along the flowchart shown in the figure. First, when the power is turned on, the CPU 8 will be set to the initial settings such as
After clearing RAM10, I/O port 6, etc.
Check whether there is any key input. Here, if any key is pressed, a flag (not shown) corresponding to the pressed key is set to "1". For example, if unit price data per unit weight has been input by operating a unit price key, the flag corresponding to that unit price key is set to "1". Then the register
Shift data from REG ₀ to REG ₅ in order, i.e. data from register REG ₀ to register REG ₁ ,
After sequentially shifting the data in REG ₁ to register REG ₂ , etc., the latest data given from weight detection section 1 is transferred to register REG ₀ , and flicker prevention processing is performed. Note that flicker prevention processing will be detailed later. Thereafter, calculation processing is performed based on the flag set in the key input processing. For example, if the flag corresponding to the unit price key is set, the unit price data per unit weight input before that unit price key and the weighing data obtained by flicker prevention processing, that is, the register
The price is calculated by calculation with the data of REG ₁₀ . After this calculation process is completed, the unit price, weight, price, etc. are digitally displayed on the display 13, and then
Repeat the loop back to key input.

Here, the flicker prevention process will be explained in detail along the flowchart of FIG. 4.

First, check whether there is any data that matches the data in register REG ₀ among the data in registers REG ₀ to _{REG 5} , and count the number of matching data.
Set to C ₁ .

Next, check whether there is any data that matches the data in register REG ₁ among the data in registers REG ₀ to _{REG 5} , and count the number of matching data.
Set to C ₂ .

Next, it is determined whether the number of data in the counter _C1 is 4 or more.

In the above judgment, if the number of data in the counter _C1 is 4 or more, the data in the register REG ₀ , that is, the latest data, is transferred to the register REG ₁₀ .

In addition, in the above judgment, the counter C ₁
If the number of data is not 4 or more, the counter
Determine whether the number of data in C ₂ is 4 or more.

In the above judgment, if the number of data in the counter _C2 is 4 or more, the data in the register _REG1 , that is, the data immediately before the latest data, is transferred to the register _REG10 . Therefore, when the above-mentioned conditions are met and the data is stable, the latest data or the data immediately before the latest data is transferred to the register REG ₁₀ , subjected to arithmetic processing, and then displayed.

Also, in the above judgment, the counter C ₂
If the number of data in is not 4 or more, register
Subtract the data in register REG ₀ from the data in REG ₁₀ and transfer the difference to accumulator ACC.

Next, it is determined whether the absolute value of the data of the accumulator ACC is equal to or greater than "5" count. Note that here, the minimum measurement unit, for example, 1 g, is set to 8 counts.

In the above determination, the accumulator
When the absolute value of the ACC data is 5 counts or more, that is, when the weight fluctuation is large, it is determined whether the data is less than or equal to zero.

In the said judgment, the accumulator
If the data of ACC is less than zero, that is, if the weight fluctuation is increasing, it is determined whether the number of times of processing of counter _C3 has reached "8". Here, when the number of times of processing of the counter _C3 reaches "8", the process proceeds to the above-described process and the data of the register REG ₀ is transferred to the register REG ₁₀ . Note that the number of times of processing of the counter _C3 is cleared to "0" in the section described below if the absolute value of the data in the accumulator ACC does not exceed "5" counts in the above, so the absolute value of the data in the accumulator ACC is is added only when the condition of "5" or more is continuously satisfied, for example, when the object to be weighed is placed on the weighing pan or when the object to be weighed is taken down from the weighing pan. Therefore, when the object to be weighed is placed on the weighing pan, the weighing data in register REG ₁₀ is held at the previous state until the number of processings on counter C ₃ reaches "8", so the value when the weight changes is not displayed.

In addition, in the above judgment, if the data of the accumulator ACC is not less than zero, that is, if the weight fluctuation is in the decreasing direction, the counter
Determine whether the number of times _C3 has been processed has reached "11". Here, when the number of times of processing of the counter _C3 reaches "11", the process proceeds to the above-mentioned process and the data of the register REG ₀ is transferred to the register REG ₁₀ . Therefore, when the object to be weighed is taken down from the weighing pan, the weighing data in register REG ₁₀ is held in the previous state until the number of processings in counter C ₃ reaches "11", so the value when the weight changes is not displayed.

Then, in the above judgment, the counter C ₃
If the number of processings of counter C3 has not reached "8", and if the number of processings of counter _C3 has not reached "11" in the above judgment, "1" is added to the number of processings of counter _C3 , and After setting the result to the counter _C3 again, the process returns to the flowchart of FIG.

On the other hand, when the above processing is completed, when the absolute value of the data of the accumulator ACC is not more than "5" counts in the above judgment, that is, the weight fluctuation is caused by slight fluctuation due to vibration etc. When it is determined that the number of times of processing of the counter _C3 is cleared to "0", the process returns to the flowchart of FIG.

The above is the method related to flicker prevention processing in this embodiment, but the present invention is not limited to this.

According to the present invention, the weight data detected by the detection means is sampled approximately periodically and sequentially stored in the data storage means, and for each sampling, the latest data among the plurality of pieces of data stored in the data storage means is sampled. After counting the number of data that match the data and at least one or more data before the latest data, it is determined whether those counted values are greater than a predetermined number, and if any of the counted values is a predetermined number In the above cases, data where the steady state clock value is more than a predetermined number of pieces is updated as new weighing data, so more accurate and stable weight measurement can be performed. When the difference between the previous weighing data and the latest data is equal to or greater than the set value for a specified number of consecutive times during weight fluctuations, the latest data is updated as new weighing data, so if the difference is greater than the set value, Values at the time of weight fluctuations until the specified number of times is reached are not output, and therefore only stable data is output, making the result display easy to view and reducing the feeling of fatigue.

In addition, the specified number of times of processing in the direction of decreasing weight fluctuation is set larger than the number of processing in the direction of increasing weight fluctuation, so that, for example, when unloading an object from the weighing pan, no intermediate value is displayed and it is ensured that it is zero. can only be displayed.

[Brief explanation of drawings]

The figures show an example in which the present invention is applied to an electronic toll scale. Fig. 1 is a block diagram showing the overall circuit configuration, Fig. 2 is an explanatory diagram showing the contents of the RAM, and Fig. 3 is the overall structure. FIG. 4 is a flowchart showing the flow of flicker prevention processing. REG ₀ ~ _{REG 5} ...Data storage means, REG ₁₀ ...
...A register that stores measurement data after flicker prevention processing.

Claims (1)

[Scope of Claims] 1. The weight data of the object to be weighed is detected as a digital quantity by a detection means, and the data detected by this detection means is sampled approximately periodically and sequentially stored in a data storage means, and each sampling After counting the number of pieces of data that match the latest data and at least one or more data before the latest data among the plurality of pieces of data stored in the data storage means, the counted values are determined to be a predetermined value. It is determined whether or not there are more than the predetermined number of pieces, and if any count value is more than a predetermined number of pieces, the data of the predetermined number or more is updated as new weighing data, while if any count value is less than the predetermined number, the previous weighing data is A weight measurement method characterized by updating the latest data as new weighing data when the difference between the data and the latest data is equal to or greater than a set value for a specified number of consecutive times. 2 The weight data of the object to be weighed is detected as a digital quantity by the detection means, and the data detected by the detection means is sampled approximately periodically and sequentially stored in the data storage means, and at each sampling, the data is stored in the data storage means. After counting the number of data that match the latest data and at least one or more data before the latest data among the plurality of data stored in If any count value is more than a predetermined number of pieces, the data of the predetermined number or more is updated as new weighing data, while if any count value is less than a predetermined number of pieces, the previous weighing data and the latest data are updated. If the difference is greater than or equal to the set value for the first prescribed number of consecutive times and the weight is fluctuating in the increasing direction, then the difference is set for a second prescribed number of consecutive times that is greater than the first prescribed number of times. A weight measuring method characterized by updating the latest data as new weighing data when the change is greater than a value and the weight is decreasing.