SU668627A3 - Device for digital indication for automatic resetting to zero of weighing apparatus - Google Patents

Description

one

The invention relates to the field of weighing technology.

Devices 1 are known that contain a product cup, an amplifying unit, an indicator device, a comparator unit and a counter.

However, the known device does not ensure sufficient performance and weighing accuracy, since there is no device for automatically setting the scale to zero.

The closest to the technical sushi to the invention is the device 2, containing, its product cup with a measuring bridge connected to the gain unit, a binary-decimal counter, a comparative block, but a binary-decimal counter connected to the memory block, the output which is connected to the indicator through the calculator and the indicator drive, and a timer.

The known device does not provide sufficient measurement accuracy due to a change in the position of the balance (tilt), vibration, air flow, hysteresis, especially after weighing a heavy object, weighing residue on the cup, or the effect of temperature on the electronic components.

The aim of the invention is to improve the weighing accuracy.

This is achieved by those. that the proposed device is equipped with a correction unit, a correction data processing unit, a division unit and two differentiators

blocks, the first differential (|) of the transfer unit is connected to a binary-decimal counter and a timer, and its output is connected to one of the inputs of the correction processing unit, its other inputs are connected to the comparison unit and to the timer, and the outputs correction data processing is connected to the correction unit and to one of the inputs of the division unit, the other input of which is connected to the second differentiating unit; second differentiate

Claims (2)

the block is equipped with a quick search unit, the input of which is connected to the second differentiating unit, and the output is connected to the correction unit: the correction unit contains a preliminary binary-decimal counter connected to the binary-decimal counter. FIG. I and 2 depict the described device, front and rear view; in fig. 3 is a block diagram of the device; in fig. 4 - time diagrams of some signals. The device of automatic installation of scales with digital indication contains a commodity cup 1, a measuring bridge 2, a gain block 3, a voltage-to-frequency converter 4, a binary-decimal counter 5 with a manual preset switch 6, a comparison block 7, a timer 8, between binary -Danny counter and preset switch 6 is installed a correction unit 9. The device also contains a differentiating unit 10, a correction data processing unit II, a dividing unit 12, a second differentiating unit 13 with a fast search 14, block pa.ti 15, calculator 16, indicator drive 17 and indicator 18. The device operates as follows. The weight data is sent to the gain unit 3 and from there to the converter 4. A pulse voltage goes to the voltage converter. living The number of weight pulses per unit of time increases, i.e. the pulse following density increases with increasing weight and vice versa, for example, one weight impulse can correspond to 0.5 g. This sequence of weight pulses goes to division unit 12, and the sequence of pulses, output This unit has a frequency that is twice as low, that is, one pulse corresponds to 1 g. This sequence of weight pulses goes to a predetermined binary-decimal counter 5. The output signal of the converter is voltage to frequency and then supplied to the comparator 7, and timer 8. The switch manual presetting 6 binary coded decimal counter 5 is set to a value less than the preset value. The automatic zero-setting process is based on continuous monitoring of the count given by the binary-decimal counter 5, and on the basis of this, the correction unit 9 controls the preset value, resulting in the preset value being changed to the value at which the result is obtained measuring 0.000 kg. In accordance with the setting of the preset value, the preset switch reads empty weights to be 9900 g. Consider an approximation to the account (I) 0000 of the value 9900 for a fast-m search. The counting of the binary-decimal counter 5 (its three most significant bits) is continuously monitored by means of a differentiating unit 13, which monitors the counting value in the range from 9800 to 999 (N). The symbol (N) means any number from O to 9. When the scale is turned on, the count of the binary-decimal counter 5 lies within the specified limits even in the case when the result of changes under the influence of various perturbing factors corresponding to ± 100 g occurred after presetting switch 6. When the differentiation unit 13 detects that the count of the binary-decimal counter 5 lies within the differentiation range, it controls with the help of the quick search block 14 the correction unit 9 of the preset value, as a result ate each period during which the measurement specified by the timer 8, the correction pulse is generated one. One correction impulse of a fast search causes an increment of 10 in the preset value in correction block 9, which in this case corresponds to 10 g. 13 and the fast search is terminated. At the same time, the actual search zero begins. The counting of the binary-decimal counter 5 is monitored by the differentiating unit 10, where the differentiation is carried out in selected limits from 999 (N) to 0000.5 and from 0000.5 to 0008.0. At the same time, the differentiator 10 can follow the direction, i.e., which side of the 0000.5 value is counted. Thus, after the termination of the fast search, the differentiating 6vTOK 10 transmits correction pulses through the correction data processing unit 9 to the correction unit 9, and the correction direction upwards remains in effect without interruption. Corrective pulses are given only for every second measurement period defined by timer 8. Correction processing unit 11 controls the dividing unit 12 so that during the measuring period when a correction impulse occurs, the dividing unit 12 is not allowed to pass the first impulse of the weight coming from the converter 4 voltage to frequency. At every second measurement period when there are no correction pulses, the first weight impulse is transmitted. Thus, a correction can be made, which advances with a step of 0.5 units of measurement, for example 0.5 g. This allows the correction operation to be performed with the same accuracy as the differentiation operation. In turn, the accuracy of the differentiation operation of 0.5 units of measurement is based on the fact that the pulse corresponding to one unit of measurement is in another state at about 50% of its duration. Thus, it is understood that the corrections take place despite the fact that the preset value increases in steps in accordance with 1 g. Finally, the score reaches 0000.5 and remains, oscillating, on both sides of it. The direction of correction alternates from up to down and back. In order to avoid unnecessary correction operations with conventional weighting, a comparator unit 7 is provided for controlling the correction data processing unit 11 so that if the rate of weight change exceeds this one, the correction is not performed. The result of the counting from the presettable binary-decimal counter 5 is fed to the memory block 15, then to the calculator 16 and through the indicator drive circuit 17 to the indicator 18. If data is entered into the calculator 16 with the help of keys (not shown) About the price, the control is used to prevent weight from leaking memory 15 until an output command is given, at which weight data is output from memory 15 and sent to calculator 16, where the product of the unit is formed prices and weights Op displays the resultant price. Claim 1. Device for automatic installation of a scale with a digital indication, containing a product cup with a measuring bridge connected to the gain unit, a binary-ten counter, a comparison unit, the binary-ten counter being connected to the memory block whose output is connected with an indicator through a calculator and indicator drive, and a timer, characterized in that, in order to increase the weighing accuracy, it is equipped with a correction unit, a correction data processing unit, a division unit and two differentiating units, the input of the first differentiating unit is connected to a binary-decimal counter and a timer, and its output is connected to one of the inputs of the correction processing unit, its other inputs are connected to the comparison unit and a timer, and the outputs of the correction processing unit are connected to the unit correction and with one of the inputs of the division unit, the other input of which is connected to the second differentiating unit. 2. The device according to claim 1, characterized in that the second differentiating unit is provided with a quick search unit, the input of which is connected to the second differentiating unit, and the output is connected to the correction unit. 3. The device according to claim 1, characterized in that the correction correction contains a previous, 1 binary decimal counter connected to the binary decimal counter. Sources of information taken into account in the examination 1. For France of France N ° 2193970, cl. G 01 G 23/14, 1974. 2. For Japan Japan .9 50-19272, 6-482, cl. G 01 G 23/14, 1975. fufj mlN) 9800 I .Y /////// X /////// L 9999 lll (XOO C 0001 () 003 {t) ff007 (t) OOOS 0000.5 fi.i