RU2401994C1 - Method of continuous weighing of materials carried by belt conveyors, system to this end and belt conveyor roller support - Google Patents

Abstract

FIELD: transport.

SUBSTANCE: readings of weight roller supports mounted on both sides of standard roller support are used, one of said weight roller supports being equipped with reference weight. Prior to operating one of weight roller supports in one idle cycle of the conveyor, empty belt weight is measured and memorised. Then two weight roller supports are used to simultaneously weigh loaded belt. Now after each complete closed path of the belt, unloaded weight is determined as a difference between total readings of weight roller support without reference weight and the weight of empty belt. At the same time, difference between readings of both weight roller supports is calculated and compared with reference weight, and in case there is a divergence, correction is introduced into unloaded weight. Weight roller support incorporates cantilever strain gages fitted between the base and the bracket and spaced apart along the rollers, reference weight being arranged on the side opposite said strain gages.

EFFECT: higher reliability and accuracy of weighing, increased efficiency.

3 cl, 4 dwg

Description

The invention relates to the field of transport engineering and weighing equipment and can be used in various technological processes associated with the continuous measurement of the weight of materials being moved on belt conveyors.

There is a method of continuous measurement of the weight of moving materials on conveyor belts, including obtaining total readings from weight rollers equipped with strain gauges [Description of the utility model to the patent of the Russian Federation No. 11604 from 06/17/1999, IPC ⁶ G01G 11/00, publ. 10.16.1999] - the voltage removed from the sensors is multiplied by the speed of the conveyor belt, forming a value that characterizes the instantaneous productivity of the conveyor. The weight of the conveyed material on the conveyor is determined by integrating instantaneous productivity.

The disadvantage of this method is that the receipt of the total readings from weight rollers is obviously considered true. At the same time, the fact is not taken into account that for a number of reasons, for example, because of a moving belt that is not uniform in the loading width, a transverse component of the force arises, which is not taken into account in further calculations. In addition, the sequential longitudinal arrangement of strain gauges makes the second of them ineffective. This is due to the fact that the first of them responds to the dynamic effect of the load moved through the stationary support, and the second reacts already to the steady-state effect. This mode of operation of strain gauges requires regular dynamic calibration, and this calibration is clearly related to the nature of the transported goods and their transportation mode.

The problem solved by the first invention of the group and the technical result achieved are to create a reliable way to continuously measure the weight of the materials being moved during their transportation on belt conveyors, which ensures high weighing accuracy while maintaining high productivity of the equipment used. Additionally, the technological capabilities of the weighing process are expanded with equal accuracy on conveyor lines with different capacities.

To solve the problem and achieve the claimed technical result in a method for continuously measuring the weight of materials being transported on belt conveyors, including obtaining total readings from weighted roller supports equipped with strain gauges, use the readings of two weighted roller supports located on both sides of the standard roller support, one of which is equipped with a reference with a load, while before starting one of the weight rollers in one idle cycle of the conveyor, the empty weight is measured The enty and the obtained value are remembered, then simultaneously the weight of the loaded tape is measured with two weight rollers, then after each full turn of the tape the shipped mass is calculated as the difference between the total readings of the weight roller without the reference weight and the weight of the empty tape, at the same time the difference between the total readings of both weight rollers is calculated, compare it with the weight of the reference load and, in case of discrepancies, amend the value of the shipped mass.

A known system for measuring weight based on conveyor scales [Description of the invention to the patent of the Russian Federation No. 2232979 from 09/23/2002, IPC ⁷ G01G 11/04, publ. July 20, 2004]. The balance contains two adjacent weighing rollers mounted with a bridge and frame and connected counter-to each other, have a counterweight, speed sensor, weight sensor, and they are equipped with a summing device connecting the weight rollers mounted on frames connected by a bridge, made in the form of two levers of equal length located along the longitudinal axis of the conveyor belt, forming a vertical angle with it, and connected by a connecting element that transmits the vertical force to the zoom lever, n and one of the arms of which has a counterweight, and the other arm along the longitudinal axis of the conveyor belt is connected to a weight sensor. As a result, the problem of increasing the accuracy of weight measurement up to 0.5-1.0% and the reliability of the work while maintaining the relative simplicity of the system design are solved.

The disadvantage of the system is that it is unable to take into account defects in the conveyor belt. Even with the perfect installation of the frame and support rollers, the tape can go sideways. The production of rubber-fabric conveyor belts is a multi-operation process, during which the used fabrics, rubber compounds and belts in general experience various kinds of loads: compression, tension, shear, bending, and combinations thereof. In case of non-compliance with the technology, poor-quality raw materials and significant wear of the equipment, these loads can be unevenly distributed both over the cross-section and over the area of the tapes, causing residual stresses and deviations in the sizes of the tape elements.

One of the manifestations of residual stresses is the “initial crescent” of the tape. When it is put into operation, an uneven working tension arises across the width, causing "pulling" of one of the sides, which, in turn, leads to even greater crescent shape. Centering sickle ribbons is very difficult, and sometimes impossible. This defect is detected, as a rule, not at the manufacturer of tapes, but only at the consumer. The high cost of the conveyor belt and the complexity of its installation, especially in the case of an extended conveyor, make the consumer put up with its indicated drawback in operation, especially since it nevertheless performs the functions assigned to it. But as soon as the consumer decides to install a conveyor scale on this conveyor (and regardless of the design and manufacturer's company), he immediately encounters the problem of calibrating the latter due to the constant “walking” of the belt under load from side to side, which he cannot reproduce from using a mechanical load simulator.

In addition, the accuracy of weighing at the level of 0.5-1.0% is theoretical. When using the scaling levers, indeed, it is possible to reduce the size of the counterweight by eight times, and the magnitude of the calibration weights by ten times. In this case, weighing errors are also recorded reduced by 8-10 times. In practice, the accuracy of weighing on scales of a similar design is at best about 7%, which is unacceptable for estimating transported goods, the total weight of which is hundreds of thousands and millions of tons.

A known system for measuring the mass of products in a stream based on the corresponding device [Description of the invention to the patent of the Russian Federation No. 2022237 dated 05/12/1991, IPC ⁵ G01C 19/18, publ. 10.30.1994], which contains a conveyor belt mounted on the base, a weighing platform, a force sensor and a signal processing circuit. An additional force sensor is introduced into the device, and the weighing platform is made in the form of two longitudinal levers arranged one below the other, the free end of the upper one resting on the first force sensor, and its second end pivotally mounted on the free end of the second lever, which rests on the second force sensor while the other end of the second lever is pivotally attached to the base, and the signal processing circuit is made in the form of two sensors for the availability of the product, a power source, two amplifiers connected by their inputs to the corresponding relevant force sensors, adder, analog-to-digital converter, microcomputer and digital display. The device provides increased reliability and high weighing accuracy, allowing to sort out the moving products by weight and adjust the packaging dispensers.

A disadvantage of the known device is that it works with small, usually portioned, masses of food. In this case, it is possible to ensure high accuracy of weighing, since it is necessary to operate with mechanisms commensurate with the clock. In the case of the inventive system of continuous measurement of the weight of materials being transported on belt conveyors, it is necessary to operate with mechanisms of general or heavy mechanical engineering capable of moving very large masses of goods with high productivity, when it is almost impossible to re-measure the mass shipped for one full cycle of the conveyor (hundreds of thousands of tons) by reference weight equipment.

The indicated disadvantages are deprived of a weight measuring system based on continuous multi-roller conveyor scales [Description of the utility model to the patent of the Russian Federation No. 11604 of 06/17/1999, IPC ⁶ G01G 11/00, publ. 10.16.1999]. The system contains a conveyor frame, standard and equipped with strain gauge sensors weight rollers, on which an endless belt is placed, and automation equipment. The equipment is placed on the load receptor in the form of a rigid metal structure with one degree of freedom of two strain gauge sensors so that the line connecting the points of application of force to the sensors is located along the axis of the conveyor belt.

The system provides high accuracy and reliability of measurement, but only with uniform loading relative to the axis of symmetry of the conveyor. Any deviation of the cent cent of the load in the transverse direction distorts the accuracy of the readings of the strain gauges. In addition, various load simulators are used to dynamically calibrate a known weight measurement system. The latter are mounted on the conveyor belt from above, articulating them on the conveyor frame. Then they turn on the conveyor and make the belt make one or several full revolutions. In this case, the controller of the conveyor scales captures the readings of the strain gauges and correlates them with the mass of the simulator and the speed of the conveyor belt, thereby calculating the value of the simulated shipped mass. The data obtained in this way are used to calculate the shipped mass and conveyor capacity. As a load simulator use roller chains, trolleys, etc.

However, no matter what simulator we take, it is not able to completely simulate the load of bulk material on the conveyor belt, and through it to the load cells of the scales. This is because the simulator has several point contacts with the tape, while the material on the tape gives a distributed load. In addition, friction always exists between the stationary simulator and the moving belt, while the material relative to the belt is always stationary. The mass of the simulator should be limited, otherwise the maintenance staff will be uncomfortable working with it. In practice, it does not exceed 100 kg. This load cannot cause the belt to move to the side if the conveyor frame in any section has horizontal movement in the transverse direction due to mounting errors. The load from the material located on the tape can be several tons and can cause the tape to move to the side. In this case, large measurement errors immediately arise, because dynamic calibration of the balance was carried out in a different position of the conveyor belt.

The problem solved by the second invention of the group and the technical result achieved are to create a fairly simple and reliable system for continuous measurement of the weight of materials being moved on conveyor belts, providing high accuracy of weighing while maintaining high productivity of the equipment used. Additionally, the technological capabilities of the weight measuring system are expanding, ensuring the weighing process with the same accuracy on conveyor lines with different capacities.

To solve the problem and achieve the claimed technical result in the system of continuous measurement of the weight of materials being transported on a conveyor belt containing a conveyor frame, standard and equipped with strain gauge weight rollers, on which an endless belt is placed, and automation equipment, use two weight rollers located on the frame with the possibility of placing between them one full-time roller support, while one weight roller support is made with the possibility of placing a reference about the load, and automation includes a weight controller, speed sensor and a central processor.

The above information from the prior art includes information on the design of weight rollers of belt conveyors used for continuous weighing of various materials (see RF patents for inventions No. 2232979 and No. 2022237 and utility model No. 11604).

The disadvantages of these scales are limited technological capabilities associated with the inability to accurately weigh, in particular, large volumes and masses of continuously moving materials.

The problem solved by the third invention of the group, and the technical result achieved, are to create sufficiently simple and reliable weight rollers of continuous conveyor belts designed to measure large volumes and masses, providing high accuracy of weighing while maintaining high performance of the serviced conveyor lines. Additionally, the technological capabilities of a weight measuring system equipped with appropriate roller bearings are expanding, ensuring the weighing process with the same accuracy on conveyor lines with different capacities.

To solve the problem and obtain the claimed technical result in the weight roller support of the conveyor belt, including a base with rollers located at an angle to each other, at least one bracket that can be attached to the conveyor frame, and two strain gauge sensors associated with the processing device of their readings, strain gauges are made cantilever, located between the base and the bracket and spaced along the rollers, and on the base from the side opposite to the placement of ten zoometric sensors, there is a platform for placing a reference load on it.

The invention is illustrated by drawings, where

- figure 1 shows a General view of a system of continuous measurement of the weight of the moved materials on a conveyor belt;

- figure 2 shows the weight roller on the front view;

- figure 3 is a weight roller on the side view;

- figure 4 - weight roller on top view.

A method for continuously measuring the weight of materials being transported on belt conveyors 1 is implemented on the corresponding device, a continuous weight measuring system, which contains a frame 2 of a conveyor 1, standard roller bearings 3 and equipped with strain gauges 4, two weight roller bearings 5 and 6, on which an endless belt 7 is placed, and automation equipment, while the weight roller 5 and 6 are located on the frame 2 with the possibility of placing between them one full-time roller 3, and the weight roller 6 is made with the possibility of Ia thereon reference prigruza 8 and automatics means includes a weight controller 9, the speed sensor 10 and the CPU 11 (which may also perform the function of a dedicated controller) and various peripherals 12, the type of monitor, a printer, a speaker, etc. - according to the standards of equipping the workplace (desk) of the conveyor line operator.

A method for continuously measuring the weight of materials being transported on belt conveyors 1 includes obtaining total readings from weighted rollers 5 and 6 located on both sides of the standard roller support 3, of which roller support 6 is equipped with a reference load 8, and before starting work with any of the weight rollers 5 or 6 in one idle cycle of the conveyor 1 measure the weight of the empty belt 7 and the resulting value is stored, then simultaneously with two weight rollers 5 and 6 and measure the weight of the loaded tape 7, then after each full revolution of the tape 7, the shipped mass is calculated as the difference between the total readings of the weight roller support 5 without the reference weight 8 and the weight of the empty tape 7, at the same time the difference in the total readings of both weight rolls 5 and 6 is calculated, compare it with the weight reference load 8 and, in case of discrepancies, amend the value of the shipped mass.

The weight roller support 5 or 6 of the conveyor belt 1 has a universal design, including a base 13 with support (support, guide) rollers 14 located at an angle to each other, two brackets 15 made with the possibility of fastening to the frame 2 of the conveyor 1, and two strain gauge sensors 4 associated with the device for processing their testimony, which is one of the elements of the automation system of the continuous measurement of the weight of the materials being moved, while the strain gauges 4 are made console, located the base 13 and the bracket 15 and are spaced along the rollers 14, and on the base 13 from the side opposite to the placement of the strain gauges 4, there is a platform 16 for placement on it, in case of technological need, as provided for in the system of continuous measurement of the weight of the moving materials on the tape conveyor 1, calibration weights, or reference weight 8, made in the form of at least one item calibrated by weight (shown conditionally).

We analyze the materiality of the features of inventions.

The method of continuous and accurate measurement of the weight of materials being transported on belt conveyors 1 is implemented using the readings of two weight rollers 5 and 6 located in a certain way along the conveyor 1, one of which (for example, 6) is equipped with a reference load 8, the weight of which (or which, if several loads 8) is a predetermined constant value.

Using this principle of measuring weight on belt conveyors 1 allows, using the minimum amount of weighing equipment, to obtain the maximum possible accuracy of weighing the moving materials.

The information necessary for the implementation of the method on the weight of the empty belt 7 for one idle cycle of the conveyor 1 is obtained before starting work, using the readings of any of the weight rollers 5 or 6. If the weight roller 6 used to determine the weight of the empty belt 7 was equipped with a load 8, then the weight of the load 8 at the end of the idle cycle of the conveyor 1 is subtracted from the total weight and this value is stored by entering the corresponding information into the central processor 11.

Actually, the process of determining the weight of materials to be transported on belt conveyors 1 includes the simultaneous measurement of the weight of the loaded belt 7 by two independent weight rollers 5 and 6 located on both sides of any single standard roller support 3. After each full revolution of the belt 7, the weight loaded is calculated as the difference between the total readings of the weight of the roller support 5 without the reference weight 8 and the weight of the empty tape 7, at the same time calculate the difference in the total readings of both weight of the roller support 5 and 6, comparing They are loaded with the weight of the reference load 8 and, in case of discrepancies, they are amended in the amount of the shipped mass. In other words, if the weight difference is equal to the sum of the weight of the reference load 8, then the central processor 11 gives this information as the value of the mass shipped for one full cycle of the conveyor. If a difference in weight is detected between the weight rollers 5 and 6 and the sum of the weight of the reference load 8, then the central processor 11 will enter the corresponding correction in the amount of the shipped mass.

Operational information from the central processor 11 is transmitted to the operator’s console (conditionally, it can be considered as pos. 12), transmitted via communication channels to an automated process control system or production system, recorded in an archiving program, etc.

The weighing accuracy obtained as a result of using this method will be quite high, but, nevertheless, during the operation of the conveyor 1, an error accumulates in the central processor 11 due to the effect on the accuracy of the indication of irreversible changes in the design of the standard roller bearings 3, wear of the belt 7 of the conveyor 1 and etc. To eliminate this error, as often as possible, for example, once or twice per shift, update the information about the weight of the empty belt 7 for one idle cycle of the conveyor 1. If you consider that the conveyor lines are usually duplicated, then this mode of operation The equipment is quite acceptable.

This ensures very high weighing accuracy, which is, for example, when using strain gauges 4 of the brand VISHAY-1260 or T60A manufactured by TENZO-M (WWW.tenso-m.ru), an average filling rate of tape 7 at 100 kg / m and speed conveyor 1 from 1.0 to 2.5 m / s - less than 1%, which is determined by the ability of the automation system to quickly respond to changes in environmental conditions due to the constancy of the weight of the reference load 8.

The system of continuous measurement of the weight of the materials being transported on the conveyor belt 1 can be implemented on the corresponding conveyor line, both newly designed and already put into operation, i.e. being modernized.

The design feature of the conveyor line is not only the presence of two weight rollers 5 and 6, one of which, namely 6, is equipped with a reference load 8, but also their special relative position. As for the location of the reference weight 8, it does not matter which of the rollers 5 or 6 is equipped with it - each of them includes a corresponding platform 16, which, if necessary, can be used for its intended purpose - the placement of the reference weight 8 or calibration weights (not shown conditionally ) As for the relative position of the weight rollers 5 and 6, here the main condition is their location on both sides of the pre-selected, for example, according to the criterion of the best availability of the standard rollers 3. Only this arrangement of the weight rollers 5 and 6 provides the necessary sensitivity of strain gauges 4 in addition to compactness 4 In the prior art, in particular, there is information about the sequential arrangement of roller bearings equipped with strain gauges (see, for example, RF patent No. 11604 for a utility model). As mentioned above, the sequential arrangement of the weight rollers 5 and 6 does not provide the necessary accuracy of weighing and requires frequent weight checks. Similarly, the location of the weight rollers 5 and 6 through two, three or more standard rollers 3 provides distortion of the weighing results. In this case, the fixed weight on the spaced roller bearings can differ significantly from each other. This is due to the fact that lateral displacements of the tape 7 moving under load begin to appear to one degree or another as soon as it comes off the support rollers 14. The more regular rollers 3 between the weight rollers 5 and 6, the more distortion there will be. . The presence of only one full-time roller 3 in this case introduces a minimum of distortion.

The automation equipment used in the design of the continuous weight measurement system includes the most common mass-produced products by domestic and foreign manufacturers, as a rule, multifunction devices, for example, SIWAREX U type 9 weight controller (its dual, etc. options) manufactured by SIEMENS (WWW.siemens. com), a speed sensor 10 of type DS-2M manufactured by VIBRO-M (WWW.vibro-m.ru) and a central processor 11 of type CPU313C manufactured by SIEMENS or similar devices. This allows scheduled maintenance and repair of automation equipment by the enterprise with minimal involvement of the designer of the weight measurement system.

The use of cantilever strain gauge sensors 4 in weight rollers 5 and 6 in comparison with, for example, compression, tensile, torsional, load cells is primarily associated with their sensitivity, ease of installation, maintenance and replacement. Their spacing along the support rollers 14 (i.e., across the width of the conveyor 1 divided by the right and left load cells 4) allows you to take into account any deviations in the design of the conveyor belt 7 and the uneven loading. In this case, the instantaneous mass of the transported cargo will simply consist of the sum of their readings. The location of the base 13 of the weight roller support 6 (or 5) and the platform 16 for placing the load 8 at a maximum distance from the bracket 15 for attaching the roller support 6 (or 5) to the frame 2 also makes the bending force on the sensitive element of the cantilever load cells 4 possible. In known solutions ( see, for example, patent of the Russian Federation No. 2232979) specifically introduce scaling (multiplication) of the final load in a smaller direction, without taking into account the fact that the real accuracy is weighted in the same direction in a smaller direction Ania.

The possibility of placing the reference load 8 on special platforms 16 allows you to pre-calculate the value of the “additional control shipped mass” during the operation of the conveyor 1, which will be present in the program for adjusting the weight of the shipped mass of transported materials embedded in the central processor 11. At the same sites 16, regardless the functionality of placing a reference load 8 on them, standard calibration weights (not shown conditionally) are also placed when calibrating strain gauges after installation AIAM carrying rollers 5 and 6, or as a result of their maintenance. Using this solution allowed to completely abandon the mechanical load simulator, which should be installed on an empty conveyor belt 7.

Thus, all of the above, including the independence of weight rollers 5 and 6, increases the accuracy of weighing continuously moving materials on belt conveyors 1. The practice of control weighings showed that in this case the measurement error is no more than 1-2%. Existing analogues have a measurement error of the shipped mass from 1% to 5% or more.

The invention is implemented as follows.

Equipping conveyor lines with weight rollers 5 and 6 can be done both in the manufacture of new belt conveyors 1 at the manufacturer, and in the modernization of existing ones. In any case, on a mounted conveyor 1 in a convenient place for maintenance on both sides of the standard roller bearings 3, weight roller bearings 5 and 6 are installed.

The conclusions of 17 load cells of each weight roller support are connected to a single weight controller 9 or to individual weight controllers for each weight roller support 5 and 6 (not shown conditionally), and the latter are connected to the central processor 11. Automation equipment is equipped with the necessary peripheral devices. After that, the equipment is set up and calibrated and the system is tested under real operating conditions. To do this, on the appropriate sites 16 of each weight roller 5 and 6 with a raised tape 7 set the calibration weights in the required quantity and calibrate the strain gages. Then, the calibration weights are removed, the tape 7 is returned to the support rollers 14, the conveyor 1 is turned on and one full revolution of the empty tape 7 is made, which is fixed by the readings of the speed sensor 10 or visually by a special mark on the tape 7, while recording the readings of both weight roller support 5 and 6. Then calculate the arithmetic mean value of their readings and for each of them determine the correction factor as the ratio of the readings of these weights to the arithmetic mean value. Then, on platform 16 of one of the weight rollers, for example - 6 (on which calibration weights were previously temporarily installed) - a reference load 8 is installed, which should now constantly stand on this roller support.

After that, the system of continuous measurement of the weight of the moving materials on the conveyor belt 1 is ready for operation.

The method of continuous weight measurement is as follows.

In idle mode, for one full cycle of operation of the conveyor 1, the weight of the empty belt 7 is measured and this value is entered into the weight controller 9.

When the conveyor 1 is turned on, both weight rollers 5 and 6, as the empty belt 7 passes, begin to weigh the conveyed material, while the speed sensor 10 constantly determines the speed of the belt 7, the values of which are taken into account in the calculation of the shipped mass.

The algorithm for continuous weighing of moving materials is as follows.

The mass M0 shipped per revolution of the conveyor belt 7 is calculated as the difference between the readings of the weight of the roller support 5 without the reference load 8 - Mbpr and the mass of the empty belt 7 - Mpl:

M0 = Mbpr-Mpl.

The mass of the empty belt 7 - Mpl is taken from the memory of the central processor 11, where it was entered during the last idle turn of the conveyor 1.

At the same time, for one revolution of the conveyor belt 7, the difference M1 is determined between the readings of the weight roller support 6 with the reference load 8 - Mspr and the mass of the empty belt 7 - Mpl:

M1 = Mspr-Mpl.

The reference load 8 should give for one revolution of the tape 7 the theoretical value of the increment of the shipped mass M2, which is calculated by the controller 9 according to the readings of the load cells 4 and the speed sensor 10 of the tape 7.

After taking the relevant readings and performing all calculations, the coefficient K is determined:

K = M2 / (M1-M0),

where M2 is the theoretical value of the increment of the shipped mass due to the reference load 8;

M1 - the difference between the readings of the weight roller 6 with a reference load of 8 - Mspr and the mass of the empty tape 7 - Mpl;

M0 is the difference between the readings of the weight of the roller support 5 without a reference weight 8 - Mbpr and the mass of the empty tape 7 - MPl.

The coefficient K can take values from 0.7 to 1.3.

The actual value of the shipped mass MD is calculated as the product of the coefficient K by the value of MO:

Md = K × MO

Further, after each full revolution of the conveyor belt 1, the process is repeated, and the actual value of the shipped mass Md, issued to the operator’s console, is summed up with the previous result:

Md _Σ = ΣMd _i

Calculation example.

There is a conveyor belt 1 with the following characteristics:

- conveyor length -10 m;

- width of the conveyor belt 7 - 600 mm;

- belt speed 7 - 1 m / s;

- productivity - 40 t / h;

- the weight of the reference load is 8-20 kg;

- The theoretical value of M2 is 400 kg.

The mass of the empty tape 7, recorded by the load cells 4, was Mpl = 100 kg.

A weight roller support 5 without a load 8 recorded after one revolution of the tape 7 the value of MBpr = 300 kg.

The value of M0 will be equal to M0 = 300-100 = 200 kg.

Weight roller support 6 with a load of 8 recorded the value of M1 = 580 kg.

The value of K for the first revolution of the conveyor belt 7 will be K ₁ = 400 / (580-200) = 1.05.

Thus, the actual value of the shipped mass after the first revolution of the conveyor belt 7 will be MD ₁ = 1.05 × 200 = 210 kg, which is recorded by means of automation and, if necessary, by the operator.

A significant increase in weighing accuracy can conditionally be illustrated by the fact that both weight rollers 5 and 6 gave different weighing results. One gave the value of the shipped mass as 200 kg, and the other, taking into account the increment of the shipped mass due to the reference load 8, as 580-400 = 180 kg, provided that the real weight of the materials moved over one full revolution of the belt 7 was 210 kg.

With further measurement of the weight of the materials being moved, the process repeats. The actual values of the shipped mass are calculated after the second and subsequent revolutions of the conveyor belt 7, the values of which are summed up, which in the end will be the value of MD _Σ = MD ₁ + MD ₂ + ... + MD _i .

As a result of solving the set tasks, a reliable and accurate method was developed for continuous measurement of the weight of materials being transported on conveyor belts, and fairly simple and reliable systems were created for their implementation and corresponding weight rollers supporting high weighing accuracy while maintaining high productivity of the equipment used, the technological capabilities of the measurement system were expanded weights ensuring the weighing process with the same accuracy on conveyor lines s with different capacities.

Claims (3)

1. A method for continuously measuring the weight of materials being transported on conveyor belts, including obtaining total readings from weight rollers equipped with strain gauges, characterized in that they use the readings of two weight rollers supported on both sides of the standard roller support, one of which is equipped with a reference load, while before starting work of one of the weight rollers for one idle cycle of the conveyor, measure the weight of the empty belt and the resulting value is stored, then simultaneously about two weighted roller bearings measure the weight of the loaded tape, then after each full revolution of the belt the shipped mass is calculated as the difference between the total readings of the weight roller without the reference weight and the weight of the empty belt, the difference in the total readings of both weight rollers is calculated, compared with the weight of the reference weight and in in case of discrepancies, they amend the value of the shipped mass. 2. A system for continuously measuring the weight of materials being transported on a conveyor belt, comprising a conveyor frame, standard and equipped with strain gauge weight rollers, on which an endless belt is placed, and automation equipment, characterized in that they use two weight rollers, located on the frame with the possibility of placing between they have one full-time roller support, while one weight roller support is made with the possibility of placing a reference load on it, and automation means include weight control , Speed sensor and a CPU. 3. A weighted roller support of a conveyor belt, including a base with rollers located at an angle to each other, at least one bracket configured to attach to the conveyor frame, and two strain gauge sensors associated with the device for processing their readings, characterized in that the strain gauge the sensors are made cantilevered, located between the base and the bracket and spaced along the rollers, and on the base from the side opposite to the placement of strain gauge sensors there is a platform for placement on it is a reference load.

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