RU2058018C1 - Weighing device for single-type articles - Google Patents

Abstract

FIELD: weight measuring devices. SUBSTANCE: device has output tank 1, feeder 3 with drive 4 and control unit 5, main weigher 6 with cup 8, unit for setting scale of measuring, additional weighers, which are electrically connected to unit for setting average value of weight of single article, unit, which detects number of articles in cup, which is connected to main weighers, means for indication results of weighing and counting articles. In addition device has clamp 14 which has tunable lifting capacity and is mounted above feeder for movement in vertical direction. Said clamp is mechanically connected to additional weighers. Lifting capacity for articles with different weight of single article is restricted by equation given in invention specification. EFFECT: increased functional capabilities. 2 dwg

Description

 The invention relates to a weight measuring technique and can be used to determine the number of products of the same type when filling container containers.

 A device for counting the number of parts by weighing [1] containing a platform, a sensitive elastic element, a strain transducer, apparatus 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 parts in a container by the average mass value of one part, calculated in advance.

 The disadvantage of this device is the increase in the error in the account of parts with an increase in the dispersion of parts by weight and the number of parts in a batch. In addition, the determination of the average value of the mass of one part on the balance, designed to weigh the entire batch of parts, leads to an additional error, depending on the accuracy class of these scales.

 Also known is a device containing two weights, a unit of a computing converter, an indicator and a recorder of the quantity and mass of the same type of product. 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 mass by the average mass value 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 invention in terms of technical nature and the achieved result is an automatic calculating scale that implements the method of weighing and counting piece products of the same type [2] containing a platform with tare capacity, force sensors, a microprocessor computing unit, means for indicating and recording the results of weighing and counting products. When using these scales, the nominal weight of one product is periodically updated with the help of auxiliary scales of increased accuracy.

 The disadvantage of the prototype is that the determination of the average value of a unit mass of products is done manually by selecting a known number of products from a packaging container, weighing them on auxiliary weights and determining the average value of the mass of the product by dividing the total mass of the products by their number. With significant deviations of the unit mass of products from the nominal, reaching in some cases 5-6%, this correction does not allow to obtain high accuracy of the product count in each batch. In addition, reduced productivity at the site of filling containers with products due to the additional time spent on adjusting the nominal mass of the products.

 The proposed weight dispenser of the same type of product contains a feed hopper, a feeder with a drive and a control unit, a basic balance electrically connected to a unit for setting the dose of products and a unit for determining the number of products in a container, the output of which is connected to an indicator, auxiliary scales mounted above the feeder and electrically connected with a unit for determining the average value of the mass of a single product, a unit for determining the number of products in a tare container connected to the main scales, means for indicating the results ozirovaniya and product accounts.

где Q_с грузоподъемность схвата;
m $\genfrac{}{}{0ex}{}{\text{(l)}}{\text{o}}$ номинальная масса единичного изделия;
Δ_в погрешность вспомогательных весов; Δm $\genfrac{}{}{0ex}{}{\text{(l)}}{\text{o}}$ |_макс максимальное отклонение массы единичного изделия от номинальной.An additional gripper with adjustable load capacity, located above the feeder and mechanically connected with auxiliary weights with the ability to move vertically, is added to the batcher, and the load capacity of the gripper for products with different unit weights should not exceed the value calculated according to the expression
Q

where Q _{with the} lifting capacity of the tong;
m $\genfrac{}{}{0ex}{}{\text{(l)}}{\text{o}}$ nominal mass of a single product;
Δ _{in the} error of auxiliary weights; Δm $\genfrac{}{}{0ex}{}{\text{(l)}}{\text{o}}$ | _{max the} maximum deviation of the mass of a single product from the nominal.

 Compared with the prototype and other analogues, the proposed dispenser improves the accuracy of counting products in each batch (container) due to the quick automatic adjustment of the average unit mass of the product during filling of the container, as well as an increase in productivity by eliminating the additional time spent on adjustment.

 In FIG. 1 presents a structural diagram of the dispenser; figure 2 is a functional diagram of the control process of dosing and counting products.

 The dispenser contains a feed hopper 1 with a protective visor 2, a feeder 3 with a drive 4 and a control unit 5, the main electronic scales 6 with a roller table 7 and a container 8 installed on them. The position of the container 8 on the roller table 7 is limited by a stop 9.

 For further transportation of the container container 8, the roller table 10 is used. The load cells 12 are mounted on the metal structure 11, on which the auxiliary weighing platform 13 is mounted (other elements of these scales are not shown for simplicity). The grip 14 (for example, electromagnetic) by means of a cable 15 is suspended on a lifting device 16 above the feeder 3.

 The output of the main scales 6 (see Fig. 2) is connected to the first input of the zero-organ 17, the second input of which is connected to the output of the unit 18 for setting the dose of products in a batch (container). The first output of the zero-organ 17 is connected to the control unit 5 of the actuator 4 of the feeder 3. The second output of the zero-organ 17 is connected to the input of the tong control unit 19. The first output of the block 19 is connected to the power supply 20, and the second with the drive 16 of the gripper 14. The output of the tong load control unit 21 is connected to the tong power supply unit 20.

The output of the load sensors 12 of the auxiliary scales through an analog-to-digital Converter 22 is connected to the first input of the division unit 23, the second input of which is connected with the output of the unit 24 for setting the nominal mass m $\genfrac{}{}{0ex}{}{\text{(l)}}{\text{o}}$ one item. The output of block 23 through the block 25 rounding the result to the nearest integer is connected to the first input of the division block 26, the second input of which is connected to the output of the converter 22. The output of block 26 is connected to the input of the memory block 27, the output of which is connected via the key 28 to the input of the division block 29 on the "3". The output of the main balance 6 through an analog-to-digital converter 30 is connected to the first input of the division unit 31 (determining the number of products), the second input of which is connected to the output of the block 29. The outputs of the converter 30 and block 31 through the amplifier-decoders 32 and 33, respectively, and the switch 34 are connected with the input of a digital indicator 35 mass and number of products in a container.

Block 18 sets the mass m _n products in the party and block 24 sets the nominal mass m $\genfrac{}{}{0ex}{}{\text{(l)}}{\text{o}}$ one product can be made in the form of comparators. The drive control unit 5 of the feeder 3 is standard and is supplied with the feeder. The power supply unit 20 of the electromagnetic gripper 14 is a thyristor voltage regulator controlled from block 21, containing a potentiometric setpoint. The tong control unit 19 comprises a reversing starter including a tong lifting actuator 16.

 The proposed dispenser works as follows.

Затем схват поднимается до положения h_o. При этом выходной сигнал силоизмерительных датчиков 12 вспомогательных весов, пропорциональный m $\genfrac{}{}{0ex}{}{\text{l}}{\text{Σ}}$ , поступает на вход аналого-цифрового преобразователя 22, выход которого подключен к блоку 23 деления, где происходит операция деления U $\genfrac{}{}{0ex}{}{\text{l}}{\text{и}}$ на сигнал U $\genfrac{}{}{0ex}{}{\text{(l)}}{\text{o}}$ , поступающий на блок 23 от блока 24 и пропорциональный m $\genfrac{}{}{0ex}{}{\text{(l)}}{\text{o}}$ . Результат деления с выхода блока 23 поступает на блок 25, где округляется до ближайшего целого числа, которое соответствует точному количеству изделий n^l, удерживаемых схватом. Сигнал, пропорциональный n^l, совместно с сигналом U $\genfrac{}{}{0ex}{}{\text{l}}{\text{и}}$ поступают в блок деления 26, выходной сигнал U $\genfrac{}{}{0ex}{}{\text{l}}{\text{ср}}$ которого пропорционален среднему значению массы единичного изделия m $\genfrac{}{}{0ex}{}{\text{(l)}}{\text{ср}}$
U

=

где U_n' сигнал, пропорциональный n^l. Сигнал U $\genfrac{}{}{0ex}{}{\text{l}}{\text{ср}}$ запоминается в блоке 27 памяти. После определения n^l отключается питание схвата 14 и изделия падают на питатель 3. По достижении массы изделий в тарной емкости 8 40% и 70% m_п операция определения m $\genfrac{}{}{0ex}{}{\text{l}}{\text{ср}}$ происходит аналогично. При этом в блоке 27 сигналы U $\genfrac{}{}{0ex}{}{\text{l}}{\text{ср}}$ суммируются. По достижении массы изделий в тарной емкости заданной величины m_п сигнал от нуль-органа 17 поступает в блок 5, привод 4 питателя 3 отключается, и набор изделий в тарную емкость 8 прекращается. При этом сигнал на входе переключателя 34 пропорционален суммарной массе m_п партии изделий в тарной емкости. Сигнал U_п на входе 2 переключателя 34, пропорциональный суммарному количеству изделий n_п в тарной емкости 8, формируется следующим образом. При подаче сигнала УС 2 (например, от кнопки) срабатывает ключ 28 и выход блока 27 памяти подключается к входу блока 29 деления, на выходе которого появляется сигнал U $\genfrac{}{}{0ex}{}{\text{(l)}}{\text{ср}}$ , пропорциональный среднему значению единичной массы изделий m $\genfrac{}{}{0ex}{}{\text{(l)}}{\text{ср}}$ , поступивших в тарную емкость, т.е.Initially, the drive 4 of the feeder 3 is disconnected, the empty tare tank 8 mounted on the roller conveyor 7 6 scales, gripper 14 is located above the feeder 3 in the position _of h, _and signals U and U $\genfrac{}{}{0ex}{}{\text{l}}{\text{and}}$ from the output of the main 6 and auxiliary 12 weights are equal to zero, zeros are lit on the indicator 34. When the control signal US 1 is applied to block 5, the drive 4 of the feeder 3 is turned on, the products begin to enter the container 8 and the signal U _and the output of the balance 6 increase. Upon reaching the mass of the products in the container capacity 8 10% of the set mass of the products in the batch in the zero-organ 17, a relay signal is generated, which is transmitted to the gripper control unit 19. In this case, the drive 16 is turned on and power is supplied from the unit 20 to the gripper electromagnet 14. Load capacity the gripper for a particular product is installed in block 21. The gripper 14, dropping to the position h _with , draws from the feeder 3 and holds a number of products, the total mass m $\genfrac{}{}{0ex}{}{\text{l}}{\text{Σ}}$ which does not exceed the established load capacity of the tong, calculated according to the expression
Q

Then the tong rises to the position h _o . In this case, the output signal of the load sensors 12 auxiliary weights, proportional to m $\genfrac{}{}{0ex}{}{\text{l}}{\text{Σ}}$ , is fed to the input of an analog-to-digital converter 22, the output of which is connected to the division unit 23, where the division operation U $\genfrac{}{}{0ex}{}{\text{l}}{\text{and}}$ on signal U $\genfrac{}{}{0ex}{}{\text{(l)}}{\text{o}}$ arriving at block 23 from block 24 and proportional to m $\genfrac{}{}{0ex}{}{\text{(l)}}{\text{o}}$ . The result of the division from the output of block 23 goes to block 25, where it is rounded to the nearest integer, which corresponds to the exact number of products n ^l held by the tong. Signal proportional to n ^l , together with signal U $\genfrac{}{}{0ex}{}{\text{l}}{\text{and}}$ enter the division unit 26, the output signal U $\genfrac{}{}{0ex}{}{\text{l}}{\text{wed}}$ which is proportional to the average value of the mass of a single product m $\genfrac{}{}{0ex}{}{\text{(l)}}{\text{wed}}$
U

=

where U _{n 'is a} signal proportional to n ^l . U signal $\genfrac{}{}{0ex}{}{\text{l}}{\text{wed}}$ stored in the memory unit 27. After determining n ^{l, the} power of the gripper 14 is turned off and the products fall on the feeder 3. Upon reaching the mass of the products in the container capacity of 8 40% and 70% m _{p the} operation of determining m $\genfrac{}{}{0ex}{}{\text{l}}{\text{wed}}$ happens the same way. At the same time, in block 27, U signals $\genfrac{}{}{0ex}{}{\text{l}}{\text{wed}}$ are summarized. Upon reaching the mass of products in the container capacity of a given value m _{p the} signal from the zero-organ 17 enters the block 5, the drive 4 of the feeder 3 is turned off, and the set of products in the container 8 stops. Moreover, the signal at the input of the switch 34 is proportional to the total mass m _{p of the} batch of products in the container. The signal U _p at the input 2 of the switch 34, proportional to the total number of products n _p in the container 8, is formed as follows. When the signal US 2 (for example, from the button) is activated, the key 28 is activated and the output of the memory unit 27 is connected to the input of the division unit 29, at the output of which the signal U $\genfrac{}{}{0ex}{}{\text{(l)}}{\text{wed}}$ proportional to the average value of a unit mass of products m $\genfrac{}{}{0ex}{}{\text{(l)}}{\text{wed}}$ entering the container, i.e.

=

где U $\genfrac{}{}{0ex}{}{\text{l}}{\text{Σcp}}$ Uср $\genfrac{}{}{0ex}{}{\text{l}}{\text{1}}$ + Uср $\genfrac{}{}{0ex}{}{\text{l}}{\text{2}}$ + Uср $\genfrac{}{}{0ex}{}{\text{l}}{\text{3}}$ . Тройная коррекция m $\genfrac{}{}{0ex}{}{\text{(l)}}{\text{ср}}$ в процессе заполнения тарной емкости обеспечивает повышение точности счета изделий. Сигнал U_и, пропорциональный суммарной массе m_п изделий в тарной емкости 8, в блоке 31 делится на сигнал U $\genfrac{}{}{0ex}{}{\text{(l)}}{\text{cр}}$ и на его выходе появляется сигнал U_п, пропорциональный суммарному количеству n_п изделий в тарной емкости, округленному до ближайшего целого числа.U

=

where u $\genfrac{}{}{0ex}{}{\text{l}}{\text{Σcp}}$ Uav $\genfrac{}{}{0ex}{}{\text{<figure-callout id="1" label="l" filenames="00000010.png" state="{{state}}">l</figure-callout>}}{\text{1}}$ + Uav $\genfrac{}{}{0ex}{}{\text{l}}{\text{2}}$ + Uav $\genfrac{}{}{0ex}{}{\text{<figure-callout id="3" label="l" filenames="00000010.png" state="{{state}}">l</figure-callout>}}{\text{3}}$ . Triple correction m $\genfrac{}{}{0ex}{}{\text{(l)}}{\text{wed}}$ in the process of filling the container provides an increase in the accuracy of counting products. The signal U _and proportional to the total mass m _{p of} products in the container 8, in block 31 is divided by the signal U $\genfrac{}{}{0ex}{}{\text{(l)}}{\text{Wed}}$ and a signal U _p appears on its output, which is proportional to the total number n _{p of} products in the container, rounded to the nearest integer.

Depending on the position of the 3 U switch, a number corresponding to m _p (1) or n _p (2) of items in the container is displayed on indicator 35. The received information about the mass and number of products in the container is recorded in the accompanying document and sent to the warehouse. The dispenser control system can be equipped with a printer for documented recording of the dispensing results and product count.

 When using microprocessor means, the dispenser operation algorithm can be implemented in software.

 The main advantage of the proposed dispenser in comparison with the prototype and other analogues is that due to the introduction of a tong associated with auxiliary weights, an increase in the accuracy of determining the average value of a unit mass of products, and therefore the number of products in a batch, is achieved. At the same time, the performance of the dispenser increases due to the exclusion of stops of the feeder to determine and adjust the average value of a unit mass of products.

 Thus, the use of the invention allows to reduce product losses during settlements between workshops or with the customer and to fully automate the accounting process.

Claims (1)

WEIGHT DOSER FOR SINGLE-TYPE PRODUCTS, comprising a feed hopper, a feeder with a drive and a control unit, a main balance electrically connected to a unit for setting the dose of products and a unit for determining the number of products in a container, the output of which is connected to an indicator, auxiliary scales mounted above the feeder and electrically connected with a unit for determining the average mass of a single product, characterized in that it is additionally introduced with a gripper of adjustable load capacity, the lifting drive of which is mounted on an auxiliary balance having, the gripper capacity for products with different unit weight must not exceed the value calculated according to the expression

where Q _{with the} lifting capacity of the tong;
m $\genfrac{}{}{0ex}{}{\text{(one)}}{\text{o}}$ nominal mass of a single product;
Δ _{in the} error of auxiliary weights;

maximum deviation of the mass of a single product from the nominal.

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