SU1566223A1 - Method and apparatus for monitoring weight of articles - Google Patents

Abstract

The invention relates to a technique for determining the weight of products during their in-line manufacturing, controlling weight characteristics relative to predetermined tolerances and levels of defectiveness, sorting products relative to established tolerances by weight, in particular, when releasing heat exchanger rods and improves productivity. The method allows weighing products with a significant decrease in the number of weight measurements during sampling control due to continuous cumulative calculation of errors in determining the average value, calculating the output quantile beyond the weight tolerance, and comparing these values with predetermined values. The method is carried out using a device including a scale 1 and a counting device, which consists of a production counting unit 2, a storage device 3 weighing results (memory unit), a calculation value distribution parameter calculation unit 4, three blocks 5 comparing the calculated distribution parameters with set values, the command generation unit 6, triggered according to the scheme And from the comparison units and stopping the weighing process, issuing the last value of the average weight and the number of weighted and usable items tsifropechat and regulator 7 product stream, which directs the flow of articles on the signal forming unit instruction or a balance, or a mine scales on the production line. 1 il.

Description

I Products

315

The invention relates to controlling the weight of an article during its in-line manufacturing, controlling weight characteristics with respect to predetermined tolerances and levels of defectiveness, and sorting products against established tolerances by weight, in particular, with the release of heat exchanger rods.

The aim of the invention is to improve.

control performance by reducing the number of measurements of the weight during sampling to the minimum necessary to guarantee the determination of the suitability of this batch relative to the established tolerances on weight and levels of defectiveness.

The method consists in that the counting device determines, by the first ten products, the mean value, the measurement error, the quantile of the tolerance for weight, and compares them accordingly with the weight tolerance set for the product with specified defectiveness levels. They should not be exceeded. If the dispersion of the controlled batch is large and the parameters of the distribution obtained do not satisfy the requirements for the product, then another product is selected;

the distributions are recalculated and compared again with the set values. This continues until the set conditions are fulfilled or the batch is not fully controlled. In this case, the products that go by weight beyond the tolerances are sorted.

The efficiency of the proposed method is achieved due to the fact that all calculations are performed in the process of monitoring between the individual weighing cycles and the entire installation operates in an automated mode.

The drawing shows a diagram of an apparatus for carrying out a method for controlling the weight of products.

The device contains scales 1 and a counting device, which consists of a production counting unit 2, a storage device 3 weighing results (memory block), a calculation unit 4 for calculating distribution parameters of values triggered by a production counting unit 2, a unit 5 for comparing the calculated distribution parameters with given values mi, block 6 of the form of commands, triggered according to the scheme And from blocks 5 of the comparison and stopping the process of weighing, issuing

the last value of the average weight and the number of weighted and usable items per digital print, and the flow controller 7, which directs the flow of products according to the signal of the command generation unit 6, either to the scale 2, or, mine the scale 2, to the production line.

Example. Lot of products in the amount of 85 pcs. loaded into the drive, where the products one by one in the automatic mode come to weighing. The results are memorized by the computer, when the number of weighted products reaches ten, the average value is calculated by the formula

 Ј.

de X weighted

average value of products;

weight of one product; the number of weighted products. Standard deviation

Xi p

Ј (xx.) 2

(.

pt

Errors in the determination of the average weight by the formula:

with t "/. n &. P

where t, is the statistical coefficient for the sample of units pi d 0, V5 of the confidence interval;

N - the number of products in the party.

The magnitude of the quantile output over the top (Q in) and lower QH) is equal to O 5-LйЈ.1. about

where is x

6 - 6

- ma. maximum allowed

x / i "n

weight value; - minimally acceptable

weight value.

In comparison block 5, the values 0.3; , 5 and, 5. Compute

values, 06; , 8 and Q§

1.1.

When the calculated values are compared with the entered ones, the comparison units 5 produce a positive signal to the instruction block 6, which operates according to the AND scheme, after which it issues a command to stop weighing, switching the flow of other products past the scales, remembering the average weight and printing it out.

The conditions of mass production are such that, without using the proposed method and device for estimating the weight of products, replacing a continuous control with a selective one is ineffective. The established level of production of products gives a small dispersion of weight, which allows, in particular, in the manufacture of rods of heat exchangers to adhere to 15-20% of the volume of control and at the same time not miss the worse batches of products, automatically switching to a more complete control plan.

the excess of tolerances on the weight of the initial sample, and then, in case of exceeding the values of these parameters over the set ones, one next product is attached to the sample each time calculating the parameters of the new distribution until reaching the zero value of the excess or until the end of control of the entire batch, reject individual products that do not meet the weight tolerance. I

2. Weight control device

up to 100% with the rejection of non-consumer products, containing scales and a block of elimination products. At the same time, the deterioration in the quality of batches manifests itself.

calculating the distribution parameters, characterized in that, in order to increase the monitoring performance, a production counting unit, a memory unit, three comparison units with back values, an instruction generation unit and a flow controller are introduced into it, wherein the distribution parameters calculation unit is interrelated with the memory unit, whose input is connected to the output of the balance, the output of the distribution parameters calculation unit is connected with the inputs of the comparison units, the outputs of which are connected to the corresponding inputs of the command generation unit, the scales are attached to the unit production accounts whose output is connected to the input of block distribution calculating the parameters, and outputs command generating unit connected to the respective inputs of the weights, the unit production accounts unit calculating distribution parameters and flow control.

Claims (1)

1. A method of controlling the weight of products, which consists in taking a sample of products from a batch, weighing each product and calculating the distribution parameters of the obtained values, which are used to evaluate the fitness of the products, characterized in that, in order to increase the monitoring performance by reducing the sample size, after weighing, calculate the average value of the product weight, the interval limit at the level of confidence probability, the excess value of the lower and upper limits set for the nominal product weight And error determining the average weight, and then comparing these values with the allowable spread of weight products and levels of de Compiled by M.Zhukov Editor N. Bobkova Tehred M. Didyk Proofreader M. Sharoshi Order 1216 Circulation 422 VNIIPI State Committee for Inventions and Discoveries at the State Committee on Science and Technology of the USSR 113035, Moscow, Zh-35, Raushsk nab. 4/5 products containing scales and a unit calculating the distribution parameters, characterized in that, in order to increase the monitoring performance, a production counting unit, a memory unit, three comparison units with back values, an instruction generation unit and a flow controller are introduced into it, wherein the distribution parameters calculation unit is interrelated with the memory unit, the input of which is connected to the output of the balance, the output of the calculation unit of the distribution parameters is associated with the inputs of the comparison units, the outputs of which are connected to the corresponding inputs of the command generation unit, the scales are interoperable are associated with a product block bills whose output is connected to an input unit for calculating distribution parameters and outputs command generating unit connected to the respective inputs of the weights, the unit products account for calculating the parameter block distribution and flow control. Subscription