JPS5954931A - Electronic balance - Google Patents

Abstract

(57) [Summary] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

[Detailed description of the invention] The present invention relates to an electronic balance.

In general, with high-sensitivity electronic balances, after the object to be weighed is placed on the weighing pan, it takes several seconds for the load measurement indication value to stabilize and stop, and also when disturbances etc. Furthermore, the time required for the object to come to rest is extended, sometimes requiring several seconds or more for the object to come to rest. In addition, the airflow for air conditioning in the air flow chamber may cause the indicated value to become unstable, and the current situation is that the measurer is struggling to find a countermeasure for this. □This invention's
The purpose of this invention is to provide an electronic balance that can automatically set and display a static value of 11 without waiting for the indicated value to become stable and static.
, ・,
.

The feature of the present invention is to detect the load in the electronic balance, the maximum value of the detected output, the step response wave, and the indicated value. Structure, value and minimum length? When the update is completed, the temporary average value of the waveform is calculated from the above maximum value and minimum value 1, and the output waveform that vibrates around the temporary average value as the central axis intersects with the temporary average value. Detect the elapsed time until it crosses again and the peak value of the waveform within that elapsed time, calculate the product of the temporary average value of the peak value and the elapsed time, and calculate the continuous positive and negative values. Yuu. Bee binary 6
．． 7 A The sum of the above products is the sum of the elapsed time f: Use the expressed □ value as a correction value, correct the already obtained provisional average □ value, and assume that value as the static value of the output. It's because it's configured.

Hereinafter, the present invention will be explained in detail based on the drawings.

FIG. 1 is a block diagram showing the configuration of an embodiment of the present invention.

, ・The load detection section 1 is
The load detection data on the plate is stored for a predetermined minute time, e.g. 0.0
The signals are converted into digital data one after another every second and output to the control unit 2. The control unit 2 is composed of a microprocessor, and the central processing unit 9 PU, processing, and o7Pm, etc. are written to control various calculations, PROGRAMMRO・A・★94, and each peripheral device. Valve lead, de, on-memory R'OM, load detection section 1
Random access memory RAM equipped with an area for storing digital conversion values of detected data and data and areas for various registers, a temporary average value Wo, an output waveform maximum value Pl, an output waveform minimum value P2, positive and It is provided with a storage device group 5 etc. for storing negative waveform half-cycle peak values H and 9, and two 9 elapsed interrenal intervals S and T, respectively, and these are connected to each other by a pass line.

This control unit 2 has a display that displays calculation results based on the 4i order signal from the control unit 2, and a 4-key system consisting of □ and □ from each i operation key and input numeric keypad. is connected. □The random access memo + JRAM detection data storage area can store up to n+1 pieces of data, and is configured so that the oldest data dn is discarded every time the latest data dQ is stored.

In addition, the load detection unit (2) is adjusted so that the gain of its servo loop is increased to bring the braking ratio close to zero, so that the beam system of the balance mechanism can always perform approximate/free vibration.

Next, we will discuss the effect. FIG. 2 is a flowchart showing a processing program for the actual male side of the present invention.

When an object to be measured is placed on the load detection section 1, its output waveform becomes as shown in FIG. , the detection data dd from the load detection unit 1 is taken into the random access memory RAM every 0.01 seconds (STI).

5T2). The value of data dQ at the beginning of placing the object to be measured is the third
As it increases every moment like section r in the figure, the data do
Each time the value is taken in, the value is read into the maximum value register and the maximum value memory, and the value is also taken into the minimum value register (ST4. S'I'5). Then, the values of the data d are displayed one after another on the display 3 (ST9.
3T1(1). Eventually, the data dQO value reaches the peak value P1.
After reaching the peak value P1 and entering the section H in FIG. 3, the peak value P1 remains in the maximum value memory, and the contents of the minimum value register and minimum value memory are updated one after another (ST6, 5T7).
). When the data dOO value reaches the downward peak value P2, the downward peak value P2 remains in the minimum value memory. In this way, the maximum value P1 and minimum value P2 in the initial total amplitude of the output step response waveform are detected, and when they are no longer updated, the output is performed using the following equation (1) using Pl and P2. A temporary average value WO of the waveform is calculated, and its value is stored (ST8)
.

Data d' taken in after the provisional average value WO is suspended
0 increases sequentially within the interval ■ in FIG. ). This □ flag S' indicates that the data dO is m smaller than the temporary average value WO. Next, when the data dO reaches WO, it is determined whether the flag S' is set, and if it is set, the flag S' is reset and the flag S is set (ST1'5, 5TIEi). This flag S indicates that data dQ exists in section (3) in FIG. When data d□ is fetched while flag S is set, register S is counted up by 1 each time data do is fetched (every 0.01 seconds) (STII, 5T21), and the peak value of that interval ■ is detected and stored in the maximum peak value register l((S
T21.3T22).

Note that the data dOO value is the maximum value P1 already stored.
If the value exceeds the maximum value, the process returns to ST5, the contents of the maximum value memory are rewritten, the contents of various registers are cleared, and the original routine is performed again (ST23). If the data d□ after the peak value is detected becomes equal to the low average value WO again, the flag S is reset and the flag T is set (ST24, 5T25). This flag T indicates that data dQ exists in section V in FIG. If data dO is fetched while this flag T is set, the register T is counted up by 1 each time the data is fetched, and the downward peak value in that section ■ is detected and the minimum peak value register is set. (ST12, , S, T 29 , , S
T30. , ST・31). , Similarly, if the data (10) is made smaller than the minimum value P2, the process returns to ST7 and the value of the minimum value memory is rewritten, the contents of various registers ψ are cleared, and the original routine is performed again. S...
'lj 3.2. ). , after the downward peak value in section V is detected, the data (the value of 10 is the low average value W
If it matches O, flag T is reset and flag S is set (S7'33°5T34). At this point, the maximum wave height value H in the section ■ has already been stored in the register H, and the time of the section ■ is known from the value of the register S, so 1. Registers H, S and registers.

A correction value ΔW is calculated based on the value of T using the following equation (2) (ST35, 5T36). .

The meaning of ΔW in equation (2) is to calculate the sum of the area (positive) shown in the shaded area of section ■ in Figure 3 and the area (negative) shown in the shaded area of section V in the sections ■ and The value divided by the sum of the times in section ■, which is the value of the low average value WO relative to the true average value in the approximate free vibration waveform.

This can be considered a bias.

Then, the low average value WO is corrected with this correction value ΔW, and the corrected value is displayed, as well as
The value of S is cleared and the display path flag is set (
ST36. ST3'7. S early 1'llll', "ST
・.

19). After the low average value WO is corrected, the data dO′□
When it is captured, proceed from 5TII to 4T2'o,
- Follow the same procedure for section ■ in Figure 3? - new value $j and time are detected, and in 5T26, since values are stored in registers L and T in interval V, those values and registers H and S in the newly detected interval Equation (2) is calculated based on the value of , and the low average value WO is further corrected (S', 'I' 2:, '?, ,'S T
28). Note that until a new correction is added to the low average value WO, the previous low average value, WO, is held.

It is displayed (ST17). Also, when the object to be weighed is removed from or added to the weighing pan, the value of data dQ becomes larger or smaller than the maximum value P1 or the minimum phosphorus value P2, so the flowchart) ST , 5
Alternatively, the process proceeds to ST7, where the low average value WO, etc. is cleared, and the original routine is executed to newly obtain the maximum and minimum values.

Thus, using the above-mentioned area with two successive positive and negative peak values every half period, the low average value is: l! Continuously corrected and displayed.

In addition, in the above example, an example was shown in which the correction value was calculated using two areas □ for each half period, but the sum of the positive and negative areas for each period of the wave □ shape is calculated by −period. The correction value may be calculated by calculating and accumulating the accumulated value for each time, and then dividing the accumulated value by the elapsed time. In this case, registers H, S, L, and T are
, T, , 28 and 5T37 without clearing them, this can be implemented by sequentially transferring them to other registers and adding them.

As explained above, according to the present invention, when the step response waveform of the top of the load detection section or the bottle mechanism enters a free vibration state, the static value is automatically determined without waiting for the vibration to stop. Since it is calculated and displayed, you can read the displayed value without having to wait several seconds to several seconds like in the past.Furthermore, by continuously updating the correction value,
・More accurate estimation is made □. Furthermore, in the electronic balance according to the present invention, the beam system of the balance mechanism always performs measurements in a free vibration state, so it is less susceptible to disturbances such as air flow caused by air conditioning facilities and disturbances caused by continuous minute vibrations. It is hardly affected.

[Brief explanation of the drawing]

FIG. 1 is a block diagram showing the configuration of an embodiment of the present invention, FIG. 2 is a flowchart showing its processing program, and FIG. 3 is a graph showing an example of the step response characteristic of the output of the load detection section. :1-Full score output part, 2-・-
Control unit, 3...Display unit, 4-Keyboard, 5-Storage device group. Patent applicant: Shimadzu Corporation representative □Attorney: Patent attorney Nishida New procedural amendment filed March 24, 1980 Electronic balance, ■: 2,
Title of the invention 3. Person making the amendment: Shin, = o: I:, Puu. Yani 7. ) - temporary shout 37
No. 8 Name (199) Shimadzu Corporation □
Representative Yokochi - Male. 4. Agent address: 15-13-5 Ugano-cho, Kita-ku, Osaka City; date of amendment order: February 228, 1982 (shipping statement).

Claims (1)

[Scope of Claims] fil Means for sampling and storing the digitally converted output value from the load detection section at predetermined time intervals, means for detecting the maximum and minimum values of the perturbation of the output value, and the maximum value and the minimum value of the perturbation of the output value. and means □ for calculating a provisional average value of the output values using the maximum and minimum values when the minimum value has been updated, and a means □ for calculating the provisional average value of the output values using the maximum value and minimum value, and a means □ that determines that the output value matches the provisional and average values after the calculation of the provisional average value. Means for detecting the elapsed one hour from the point to the time when the point coincides with the point again, and detecting the value of the output value in the two directions or downward direction within that elapsed time. and means for calculating the product of the difference between the peak value and the provisional rights value and the elapsed time. The provisional average value is corrected by adding the above products of the two peak values (bidirectional and downward), and dividing the added value of the products by the sum of consecutive elapsed times as a correction value. An electronic balance configured to estimate the corrected provisional average value as the static value of the vibrating output value. , , , +21 Continuously calculate the above product after estimating the static value □ ・Sequentially □” Second correction: Correct, characterized in that it is configured to update the value and calculate the static value. A one-electronic balance according to claim 1.・
□