SU1352233A1 - Digital scales - Google Patents

Abstract

The invention relates to the field of information and measurement technology. The purpose of the invention is to increase the speed of the balance. The scales contain a sensitive element 1, a load-bearing platform 2 with a load 3, a suspension system 4, a non-compensation converter 5 consisting of an LED 6, a photodetector 7 and a slit diaphragm 8, a magnetic system 9 consisting of a permanent magnet 10 and a measuring coil 11, register, generator 13, frequency divider 14, generator 15, counter 16, comparator 17, key 18, load compensation current source 19 and tare compensation source 20, adder 21 and synchronization device 22. The introduction of new elements and the formation of new connections between the elements of the device make it possible to directly convert the non-compensation signal into an equilibration signal. The pulse frequency at the output of the comparator 17 is determined from the ratio between the pulse frequency and the natural frequency of the moving part of the balance, in order to ensure a small error from the pulsations at the output of the balance. 1 3.p. f-ly, 3 ill. i (L o in y u ch e soo with

Description

FIELD: informational materials. measuring technique and can be used in various fields related to the measurement of body mass.

The purpose of the invention is to increase the speed of the balance by directly converting the uncompensation signal into a balancing signal.

FIG. 1 shows a structural diagram of the scales; FIGS. 2 and 3 are a functional diagram of a synchronization device and its timing diagram.

The balance contains a sensing element 1 with a load-receiving platform 2 and a load 3, a suspension system 4, a non-compensation converter 5 consisting of an LED 6, a photodetector 7 and a slit diaphragm 8, a magnetic system 9 consisting of a permanent magnet 10 and measuring cathode 1 1 register 12, controlled oscillator 13, frequency divider 14, reference generator 15, cyclic counter 16, comparator 17, key 18, sources of load compensation current 19 and tare compensation 20, adder 21, synchronization device 22 consisting of two elements AND 23 , 24 and adjustable about one-novibratora 25, and the reading device 26.

The sensing element 1 is mechanically connected to the measuring coil 11 of the magnetic system 9. The output of the non-compensation converter 5 is connected to the input of the controlled generator 13. The output of the reference generator 15 is connected via a cyclic counter 16, phase comparator 17, switch 18 and adder 21 to the measuring output the coil 11 of the magnetic system 9. The outputs of the sources of current compensation load 19 and compensation tare 20 are connected respectively to the second inputs of the key 18 and the adder 21. The information output of the cyclic counter 16 is connected via a register 12 with the same input of the reading device 26, and the output of the controlled generator I3 is connected to the input of the frequency divider 14, the output of which is connected to the second input of the phase comparator 17 and the first input of the synchronization device 22 connected to its second input and output, respectively, to the output of the reference generator and the counting input register 12.

0

five

0

25

0

35 and

The first input of the synchronization device 22 is connected to the first input of the second element I 24, the output of which is connected to the output of the sync-i device 22 of synchronization and the input of an adjustable single-oscillator 25 connected by its output to the first input of the first element I 23, and the second input of the synchronization device 22 connected to the second input element And 23, the output of which is connected to the second input element And 24.

Scales work as follows.

Previously, in the process of fabricating and element-by-stage adjustment of the weights, the frequency of the controlled oscillator 13 fnp is controlled at zero control voltage until the condition

f.tr f

N7. N, e

pulse frequency at the output of the reference generator 15;

the number of pulses at the outputs, respectively, of the divider frequency 14 and the cyclic counter 16.

The output current of the tare compensation current source 20 is adjusted when there is no load 3 at the load receiving platform 2 and the locked key 18 until the balance of the movable part of the balance reaches equilibrium, at which the output voltage of the non-compensation converter 5

Where

N

14

f. N, 6 Mon

equals zero.

40

When you turn on the scales adjusted in this way, between signals equal to

frequency and -, - at the inputs of the phase-NH N, 6

first comparator I7, an arbitrary phase shift occurs first, and the pulses at the first input of the phase comparator 17 are delayed 45 with respect to the pulses at its second input, followed by a constant period

T some interval

50

le. At the output of the switch 18, current pulses are received, creating additional force in the compensator coil 11, is proportional to the average current 1 - When this happens, the equilibrium is disturbed, becomes "O" and the frequency fup increases, which in turn reduces the delay t and decreases

medium current

I o j

This process is beyond 3

It is lowered when ut 0 is set, and O and the frequency f returns to its original value, which is the initial state for subsequent weighing.

In the measurement mode, when load 3 is set by mass t const to load area 2, the sensitive element 1 is displaced, a signal appears at the output of non-compensation converter 5, resulting in the frequency fsbix frequency at the output of frequency divider 14, where d - frequency increment proportional to the value of the imbalance signal. When fgbiK frequency changes relative to fg, the phase relationships between the sequences of pulses following the outputs of elements 14 and 16 change. The phase shift at the input of the phase comparator 17 (and Achit and the average current in the coil lj increases until the sensitive element I occupies the initial state.

Wits equality fgbix, O and the phase shift accumulated during the transition process l Lp ... inep at the output of phase comparator 17 will become equal.

The steady state phase shift is converted into a code using a synchronization device 26 and a register 27.

In the absence of a signal at the output element And 24 of FIG. 2) the output potential 1 is set at the output of the controlled one-shot 25. and from the reference generator 15 through the element 23 to the input of the element 24 receives the pulses of the reference frequency. At the moment of the appearance of a pulse at the output of the divider 14, a clock pulse appears at the output of element 24, the triggering one-oscillator 25, which sets the potential O at the input of element 23, as a result of which the output of element 23 sets the signal O and at the output of element 24 - CTBJTOT. The time constant of the one-shot 25 thus determines the display time, and the ability to control the one-shot 25 allows the display time to be changed. With this method of obtaining a digital reference, the code in the cyclic counter 16 is similar to an exact ruler, the number of gradations is 52233-

the swarm is equal, the beginning of the count is synchronized with the beginning of the interval d, and the end of the interval At records the code pattern dN corresponding to At, which is indicated on the reading device 28, on this ruler.

To obtain the necessary accuracy of reference, the capacity of the cyclic

Q counter 16 is necessary to choose the outcome of the given division price and the limits of measurement of the weights. At the same time, the frequency of the signal at the input of the phase comparator 17 is equal to the frequency of the reference gene g of rator 15 divided by the maximum value of the cyclic counter 16. The frequency of the pulses at the input of the phase comparator 17 is determined from the ratio between the frequency of the second pulse and the mobile frequency - owls, to ensure a small error from the pulsations at the output of the scales (the error is within the limits of the resolving

25 abilities).

For example, with N, 10 (five digits of the scale), fenxi fg 10 Hz, fs (100 Hz, and using standard controlled

3Q generator 13 PNCh type KR 1108PP1 with an initial frequency of 10 Hz, N 10. In the nominal mode of operation of the PNCh, the drift of zero scales is minimal.

five

0

Claims (2)

1. Digital scales containing a sensing element with a weighing platform and a suspension system, an uncompensating converter, a magnetic system mechanically connected to the sensitive element, a reading device, a controlled oscillator, a reference generator, a cyclic counter, a phase comparator, a key, sources of load compensation current and tare compensation and an adder, the output of the non-compensation converter is connected to the input of the controlled oscillator, the output of the reference controller is connected via a cyclic counter, the phase co comparator, and an adder -key to entry of the magnetic system, and outputs load current sources compensation and tare compensation are connected respectively to the second key-input adder of m- lichayuschies in that, for the purpose dressing 11sheni "operating speed by direct conversion 0 five signal of non-compensation in the control signal, they entered the register, frequency divider and synchronization device, the information code of the cyclic counter is connected through the register with the same input of the reading device, and the output of the controlled oscillator is connected to the input of the frequency divider, the output of which is connected to the second inputs phase comparator and the first input of the synchronization device connected by its the second input and output COOT. respectively to the output of the reference generator and the counting input of the register. 2  P p p p p p p p p p p / iiiHiiniiiiiiiiiiiiiiiiiiiHiiiiiiiiiiiiiiiHiHiiiiiiiiiiiiiiiiiHiniiiiii 5L  t / Hduffatfuu Editor M.Tovtin Fig .: Compiled by S. Shakin Tehred M. Morgenthal Order 5553/36 Circulation 694 Subscription VNIIPI USSR State Committee for inventions and discoveries 113035, Moscow, Zh-35, Raushsk nab., 4/5 Production and printing company, Uzhgorod, st. Project, 4 2. Be sy according to claim 1, characterized in that their synchronization device contains the first and second And elements and an adjustable single-vibrator, the first input of the synchronization device being connected to the first input of the second And element, the output of which is connected to the output of the synchronization device and input adjustable one-shot connected to its output to the first input of the first element And, and the second input of the synchronization device is connected to the second input of the first element And, the output of which is connected to the second at the input of the second element I. Go Sync. 27 P Proofreader I. Muska