RU1783316C - Device for determining number of monotypic objects in batch - Google Patents

Abstract

Use: weight measuring equipment. SUMMARY OF THE INVENTION: the device comprises load cells (4), 1 adder (5). 1 amplifier (6), 2 analog-to-digital converters (7,9), 1 differential amplifier (8), 1 zero-organ (10), 1 comparison element (11), 1 memory register

Description

The invention relates to a weighing technique and can be used in various industries to determine the number of items of the same type when filling a container.

A device is known for counting the number of parts by weighing, comprising a platform, a sensitive elastic element, a strain transducer, equipment for indicating and recording the mass and number of parts in a container. The number of parts in a batch is determined by dividing the total mass of the parts in the container by the average value of the unit mass of the part, calculated in advance. The disadvantage of this device is the increase in part count error with an increase in the dispersion of the unit mass of parts and the number of parts in a batch. In addition, the determination of the average unit mass of parts on a scale designed to weigh the entire batch of parts causes an additional error depending on the class the accuracy of the indicated weights.

A device is also known that contains two weights, a unit of a computing converter, an indicator, and a recorder of the quantity and mass of similar products. The entire batch of products is placed on large scales, and one or more products are placed on small scales and the average mass value of one product is determined. The number of products in a batch is calculated by dividing the total weight by the average weight of one product. Due to the additional input of small weights, this device provides a more accurate determination of the average mass value of one product, but does not exclude an error due to the dispersion of products by weight. This error increases with an increase in the number of products in a batch.

The closest prototype of the present invention is a device comprising a container mounted on an electronic scale, a unit for setting the dose mass of the items, a division unit, an electronic key, a memory unit, an apparatus for indicating and recording the quantity and weight of items in a batch. In this device, items are weighed in small doses of a given mass, the number of items in each dose is determined by dividing its actual weight by the nominal weight of one item, the calculation results for all doses are summarized and the number of items in the batch is determined. The advantage of this device in comparison with

other analogues are that in it the determination of the number of objects in each dose is carried out by dividing its actual mass by the nominal mass of one object without determining the average value of a unit mass of the object. However, this does not exclude the occurrence of an error in the counting of objects, due to the inevitable error in the dosage of objects during the collection of each dose in a batch and the magnitude of the dispersion of objects by mass.

The purpose of the invention is to improve the accuracy of counting items in a batch.

This goal is achieved by the fact that in the known device containing a container connected with load cells connected to a computing unit made with a zero-organ, a dose mass adjuster, a memory unit, a first divider and a first amplifier-decoder, two digital indicators and digital printing mechanism, an adder, an amplifier, first and second analog-to-digital converters, a differential amplifier, a second amplifier-decoder, a memory register, a digital-to-analogue converter are introduced into the computing unit a developer, a set point dose calculator, a comparison element, a subtractor, a second divider and a key, the load cells being connected through an adder and amplifier to the first input of the differential amplifier and the input of the first analog-to-digital converter, the output of which is connected through the first amplifier-decoder to the first digital to the indicator, the input of the second analog-to-digital converter is connected to the output of the differential amplifier, and the output is connected to the first input of the zero-organ and through the memory register and digital-to-analog a new converter to the second input of the differential amplifier, and the dose mass regulator is connected to the second input of the zero-organ, with the second digital indicator connected through the second amplifier-decoder to the output of the memory unit, the target dose mass calculator is connected to the first input of the comparison element and through the first divider to the first input of the subtractor, the second input of the comparison element is connected to the output of the second analog-to-digital converter, and the output of the comparison element through the second divider is connected to the second input a reader whose output is connected via a key to a memory unit.

In FIG. 1, a functional diagram of a device is given; in FIG. 2 is a functional diagram of a unit for setting an estimated dose of objects.

The device contains (Fig. 1) a feed hopper (not shown in the diagram), a feeder 1 with a drive, a container 2 mounted on a platform 3, supported by load cells 4, the output of which is connected to the first analogue through the adder 5 and signal amplifier 6 digital converter (ADC) 7 and differential amplifier 8. The output of amplifier 8 is connected to the second ADC 9, the output of which is connected respectively to the input of the zero-organ 10, the comparison element 11 and the memory register 12. The second input of the zero-organ 10 is connected to the mass regulator 13 tz dose of subject . The second input of the comparison element 11 is connected to the output of the setter 14 of the calculated dose of tr objects. The output of the memory register 12 through a digital-to-analog converter 15 is connected to the second input of the differential amplifier 8. The output of the setter 14 is connected to the input of the divider 16, and the output of the comparison element 11 is connected to the input of the divider 17. The outputs of the dividers 16 and 17 are connected to the input you a reader 18, the output of which is via key 19, a memory unit 20, an amplifier-decoder 21 is connected to a digital indicator 22 of the number of items in a batch. The output of the memory unit 20 through a key 23 is connected to the first input of the transcriptor 24, the output of which is connected to a printing machine (printer) 25. The output of the ADC 7 through an amplifier-decoder 26 is connected to a digital indicator 27 of the mass of objects in a batch. In addition, the output of the ADC 7 through the key 28 is connected to the second input of the transcriptor 24.

The master 14 contains (Fig. 2) master 29 of the nominal unit mass of the item; the setter 30 of the maximum error Dpah weights; master 31 max

the smallest deviation of the unit mass from the nominal; the first multiplier 32 by a constant coefficient of 0.5; the adder 33, the divider 34, the second multiplier 35 and the ADC 36. In the setter 14, a signal Up is generated, proportional to the estimated mass tr of the dose of objects calculated from the condition

GPR Pr-GPo1

where pr - the number of items in the estimated dose;

„0.5 m0 (1J -Lpach

 R

A m b quiet

A predetermined mass of TK of the dose of objects is set by the setter 13, proceeding from the condition. Wherein .

The device operates as follows. In the initial state, the feeder 1 is turned off, the tare capacity 2 is installed on the platform 3, the signal UV at the output of the ADC 9 is zero, the zeros on the indicator 22 are on, the weight of the tare capacity 2 is displayed on the indicator 27. About the memory register 12 is compensated for the mass of the container 2 and the zeros on the indicator 27 light up.

After turning on the feeder 1, the objects begin to flow into the container 2, the load on the load cells 4 increases, and the signal 1) Φ increases in proportion to the total mass of the objects 2 entering the container. When the null-organ 10 is triggered, the drive of the feeder 1 is turned off and the flow of objects into the container 2 is stopped. In block 11, the signal 11ph is compared with the signal Up. Since if is always less than Up, the signal Dif at the output of block 11 is greater than zero. The signals Up and IF arrive at the dividers 16 and 17, respectively. At the output of the divider 16, the signal is proportional to the number of objects pr at the calculated dose mp, and at the output of the divider 17, it is proportional to the number of objects Dpf, corresponding to IF The value of Dpf is rounded to the nearest integer. The signal at the output of the subtractor 18 is equal to Pf pr - Dpf

and corresponds to the actual number of items in a given dose.

When a control signal is supplied, the key 19 passes the signal to the memory unit 20, where it is stored. The DJ- signal (for the first dose of pf) from the output of the memory unit 20 through the amplifier-decoder 21 is fed to the indicator 22. Then, by the signal Set.O, the load-measuring circuit is zeroed, after which feeder 1 is turned on and the cycle for collecting and storing the following doses of objects similarly. After the k-th dosing cycle, the container 2 is full and the set of items is stopped. On the indicator 22, the number pЈ of subjects in the batch is indicated, and on the indicator 27 their total mass mt is indicated. When a control signal is applied to the keys 23 and 28, the number and mass of objects in a given batch are recorded on the tape of the printing machine 25. At the same time, the memory unit 20 is zeroed and the device is prepared to determine the mass and number of objects in the next parotia.

Claims (1)

The claims A device for determining the number of items of the same type in a batch, comprising a container connected with load cells connected to a null organ, dose mass adjuster, memory unit, first divider and first decoder amplifier, two digital indicators and a digital printing mechanism, characterized in that, in order to increase accuracy, an adder, an amplifier, a first and a second analog-to-digital converters, a differential amplifier, a second are introduced into the computing unit a amplifier-decoder, a memory register, a digital-to-analogue converter, a unit for calculating the dose rate of an object, a comparison element, a reader, a second divider and a key, the load cells being connected through an adder and an amplifier to the first input of the differential amplifier and the input of the first analog-to-digital converter, whose output is connected to the first digital via the first amplifier-decoder to the indicator, the input of the second analog-to-digital converter is connected to the output of the differential amplifier, and the output to the first input of the zero-organ and, through the memory register and the digital-to-analog converter, to the second input of the differential amplifier, and the dose mass regulator is connected to the second input of the zero-organ, the second digital indicator is connected through the second amplifier-decoder to the output of the memory unit, the setpoint calculator for the dose of objects connected to the first input of the comparison element and through the first divider to the first input a subtractor, the second input of the comparison element is connected to the output of the second analog-to-digital converter, and the output of the comparison element through the second divider is connected to the second input of the subtractor, the output of which is connected via a key to the input of the memory unit. fi. g