JPS6383619A - Electronic balance - Google Patents

Abstract

PURPOSE:To select accuracy suitable for particular uses at any time by providing a data-stableness judging means and a data-stableness display means for each of plural time-series data. CONSTITUTION:A load-electricity transducing part 1 transduced a load W on a pan 2 into an electric signal and outputs numeric data after A-D conversion 3 at specific intervals of time. A data processing part 4 consists of a CPU5, a RAM7, etc., and the RAM7 is provided with the respective X-, Y-, Z-registers, etc. for storing time-series data temporarily, counters, flags, etc. The counters C1-C4 count up every time time-series data of the respective registers are inputted and are reset to 0 when data becomes unstable and a digital filter is destroyed. The flags S1-S4 are set to '1' when processing data of the digital filter of the corresponding order become stable, or to '0' in other cases. A display part 8 displays 9 load data after processing 4 numerically and is provided with stableness marks M1-M4 corresponding to the respective digital filters, so that they are displayed for each order.

Description

[Detailed Description of the Invention] <Industrial Application Field> The present invention relates to electronic balances, and in particular, to removing noise components from time-series data obtained by sampling weighing signals containing noise at intervals of time T. Related to electronic balances using digital filters.

<Prior art> Electronic balances convert the analog output of the load-to-electricity converter into A-
The data is sampled and converted into numerical values by a D converter at predetermined time intervals T, but conventionally, a method has been used in which noise components are reduced by subjecting this numerical data to arithmetic averaging processing.

In response, the applicant has proposed (unknown to the public) in Japanese Patent Application No. 60-262147 an electronic balance with a large amount of noise attenuation and a fast display response by using a digital filter.

The configuration of the digital filter is to filter the primary time series data (
X, ), when the second time series data is (Y7),
For example, it is shown by the following formula.

Furthermore, when the tertiary time series data is (Z,,), this is expressed, for example, by the following equation.

<Problems to be solved by the invention> In an electronic balance using such a digital filter, a stability display mark is provided along with a data display,
I am planning to read the measured value when this lights up. However, as the number of orders increases, it often takes time for the final digital filter to become stable, which is a problem that irritates the user.

On the other hand, depending on the application, a fast response speed may be required even if the measurement accuracy is somewhat rough; conversely, high measurement accuracy may be required even if the measurement takes time.

SUMMARY OF THE INVENTION An object of the present invention is to provide an electronic balance in which the stable state of each digital filter of multiple orders can be recognized and the accuracy can be selected at any time depending on the application.

<Means for solving the problem> The electronic balance of the present invention converts a load into an electrical signal, and samples the electrical signal at predetermined time intervals T to obtain primary time series data (X7). In an apparatus for obtaining time series data of multiple orders by serially processing data using a plurality of digital filters, a means for determining stability of data is provided for each of the time series data of the plural orders, and
It is characterized by providing stable display means for each time series data.

Each order digital filter and each stability determining means of the present invention are constructed by a digital computer.

<Embodiment> FIG. 1 is a block diagram showing the overall configuration of an embodiment of the present invention.

The load-electricity converter 1 converts the load W on the weighing pan 2 into an electrical signal. The A-D converter 3 operates for a predetermined time T1, for example 0.
．． Digitally converted numerical data X4 is output every 2 seconds. This includes noise in addition to the load W. The data processing section 4 includes a CPU 5. ROM6. It is equipped with a RAM7, and the RAM7 includes an X register (XO to X3) that temporarily stores time series data, an
es).

X register (20~Z+s), U register (U o~U
Ss), VL/Gislis Vo~V+s),
It has counters, flags, etc. The ROM 6 stores ten programs as described below. counter C,
, C2+C3+C, are counted up each time the time series data of each register is input, and are reset to 0 when the data becomes unstable and the digital filter is destroyed. Flag SI+S2. S3. S4 is set to "1" when the data processed by the digital filter of each order is in a stable state, and is set to "0" when it is not yet in a stable state. The display section 8 displays the load data processed by the data processing section 4 on a numerical display 9, and also includes four stability marks M+, Mt, Ms, and Ma corresponding to each digital filter.

Load data and stability mark display data are output terminal 10.
It can also be transmitted to the outside through.

FIG. 2 shows a flowchart of a program according to an embodiment of the present invention.

In the initial settings, the X register.

X register, S register, counter c,,C2.

C3, C, and flags S+, Sz, S3, and S4 are cleared. As the first stage digital filter (
Use the same formula as Equation 11. Also, among the secondary time series data (Y,) obtained by this digital filter, the past 1 at time n
Maximum value of 6 data M a x (n) = M a x (Yn-N+
-+, -1Yn) and the minimum value M in (n) = M in (Yll-Mt-
1,---, Yn 1 difference is found. When this value falls within 4 or less, Max (n) - Min (n) ≦ 4 - (3), the 16 time series data at that time are judged to be stable, the flag Sl is set to 1, and the average value lb′“9 is calculated, and the first filter corresponding to the first digital filter is
The stable mark M1 is driven to light up.

The same formula as in equation (2) is used as the second stage digital filter. (4) V calculated in 2. In order to use the initial value as the initial value, set Y to each digit of the register in the above formula when n=1.

will be introduced. The fifth term and subsequent terms in the above formula are Y n-4, Y, , -
,.

Y□12 is 3 out of 4 samplings.
2 indicates that only the first digital filter processing is performed and the second digital filter processing is not performed.

When the difference between the maximum and minimum values of the past 16 data at time n among the tertiary time series data (Z7) obtained by this digital filter falls within "4 or less" as in equation (3). , the time series data (Z,) is determined to be stable, the flag S2 is set to 1, the average value at that time is calculated, and the second filter corresponding to the second digital filter
The stability mark M2 is driven to light up.

Similarly, it is configured by a third stage digital filter, and fourth time series data (Ufi) is created. Then, when the difference between the maximum and minimum values of the past 16 data at time n among this time series data (U,,) falls within "4 or less" as in equation (3), then the time series data (U,,) U,
) is determined to be stable, the flag S,=1 is set, and the third stability mark M3 corresponding to the third digital filter is driven to light up.

Similarly, the fourth stage digital filter is configured to create the fifth time series data (V,), and when it is determined that it is stable in the same way, the flag 54 is set to 1, and the fourth Compatible with digital filters. The fourth stable mark M4 is driven to light up.

In this way, as the data input to the data processing unit 4 is stabilized, the first stable mark M1, the second stable mark Mz, the third stable mark M3, and the fourth stable mark M
4 lights up in sequence.

In such a state, for example, due to fluctuations in the load W,
The maximum value Max (n) and the highest value Min (n
) difference is Max (n) −M i n (n)≧6 t・−
(If it increases to 81, all flags S+, S2, S
z.

S4+ is all cleared to 0 and all stable marks M+, Mz, M3, M< are erased. And at the same time, the first. Second. Third. All fourth digital filters are destroyed and the program returns to the start.

Similarly, when the third-order time series data (Zi) generated by the second-stage digital filter becomes unstable as shown in equation (8), the digital filters after the second digital filter are destroyed, and the Result, stability mark Mz, M
31M4 is deleted. In this way, when any time series data becomes unstable, the stable mark corresponding to that digital filter and the subsequent stable marks are erased.

In addition to lighting the stability mark on the display, the stability display means of the present invention can transmit the data to the outside using a cord from the output terminal 10, display it on an external output device, and print it out.

As the stability determination conditions for time series data of the present invention, various known determination conditions can be used in addition to those shown in the above embodiments.

<Effects of the Invention> According to the present invention, whether or not time-series data is stable is displayed for each stage of the digital filter. If you need data with a quick response, even if it is a slightly rough measured value, read or output the data when the first stage digital filter is stable, and conversely, even if the response is a little slow, disturbances etc. can be sufficiently removed. If you need the same data, process the data by changing the balance between stability and responsiveness, such as reading or outputting data when all the digital filters in each stage are stable. be able to.

[Brief explanation of the drawing]

FIG. 1 is a block diagram showing the configuration of an embodiment of the present invention, and FIG. 2 is a flowchart showing a program of the embodiment of the present invention. 3-A/D converter 4-Data processing section 8--Display section Mi-Stability mark Fig. 1

Claims (1)

[Claims] Primary time series data {X
In an apparatus for obtaining multiple-order time-series data by serially processing data of _n} using a plurality of digital filters, a means for determining stability of data is provided for each of the multiple-order time-series data, and a data stability determination means is provided for each of the multiple-order time series data, and An electronic balance characterized by being provided with a stability display means.