SU1278598A1 - Continuous weighing machine - Google Patents

Abstract

The invention relates to weighing equipment and allows to increase accuracy by eliminating the component error due to the instability of the transfer coefficient of the load element, as well as variations in the Earth's gravitational field at various points. The measured mass is applied to the platform with the reference mass, the resulting forces causing a change in the signals at the output of the force-measuring elements.

Description

to

00 1СЛ

with

100

FIG. 2

which arrive at the inputs of the subtraction unit and the input to the inputs of the sum of orthoz 12 to 13 (LS), the output of which will be signals proportional to the corresponding algebraic sum of the difference of the signals of the load-bearing elements, the partial of these sngnaloz is formed in block 6, the signal enters the input of the AC 14, the input of the Minus of which is postoy; from the i-ial-1 from the output of the setpoint, 17 fixed lines. WITH

The invention is fire-resistant to weight-measuring equipment, in to devices for weighing, about 1: 1G P1i and bulk materials.

The purpose of the invention is to ensure the accuracy of the point due to the exclusion of components, the e-th error, due to non-stability; This is the ratio of the conversion factor to the structural dimension of the element, as well as the variation of the gravitational field Zeichln B of its various points.

Ma FIG. 1 shows a functional dispenser; in fig. 2 - the functional scheme of the block of computation of a plan for a cuvg of its mass calculation; on, 3-functional c; xe; -. ia bp: the eye of control.

The dispenser {FIG. 1) content; power supply unit 1 with bupker 2, weight 1; tel block 3, block 4, whose output through the amplifier is 5 g; l, the connection is not Nen. with a feeder 1, tllchazh; NGP mehash-Ezm b, the input of which i exa1n-1ches5si is connected with the feeder, and the ЕЫ-stroke with the input of the weight measuring unit 3, 7 calculating the current mass value, the first input connected with the weight trick 3. The second output the weighing unit 3 is associated with the second: the input of the calculation unit 7. The output of the last is connected to the input of the control unit 4. In this case, the weight measuring unit 3 contains two force-measuring: - 8 l 9 lints, platform 10, made in the form of bulk, supported by two meters and 8 x 9, you output-h 1h signal nots on the Bbiii input , block 18 multiply ;, n, the second input of the KOTOpoio input signal from the setpoint 17 is positioned: signals. From the exit; block 18 is clever -; the signal is proportional and the measure e - :: oh mass arrives at the input of the LAN 15, the other input of the jcoToporo receives the signal from the set point of the set of 17 constant signals, the normal weight of the feeder and the bunker of the pattern. 1 hp f-ly, 3 ill.

the course of each of which is consistent with one of the outputs of the DecOi-i3Me; Hr; enbHoro block 3. Input 5 follows its mechanical connection} 1 with the cargo platform 10 at the point raspole; 1; e; between its supports on the rigging elements 8 and 9. The standard mass is placed on the console section of the load receiving platform 10.

Claims (2)

The block 7 for calculating the a-current value of the i-s mass (Fig 2) contains an approximate totalizer 12-13, a block 16 division, the first input of which is connected with the move: altibrainesco. adder 13, the output of block 16 dividing the connection 1 {with input plus; un; selector adder b &b5; one iinus of which is associated with the first output: - unit 17 constant signals, unit 18 multiplying, the first BHO, whose connected to the output of the algebragic sum of the 17 fixed signals (out, yy of the block 18 y7.ps; the keynote for the input of the Flat-sum of the European sum of 15, the start of which is connected to the third output of the setter 17 constant signals. ЕБ: HOD of the algebraic adder 15 is connected with the output of block 7, the current of the current has fallen out; Ehsd which is connected to the input Eglss algebraic 2; th cyi-it-iarorm 12 n input Plus loggeraic with corner 13, while the second input of block 7 for calculating the current, the mass is connected to the input Plus algebra) of the actual number; ator 12 and input Kiggus algebraic adder 13. Control unit 4 (FIG. 3) consists of integrator 19, two algebraic adders 20 and 21, switch 22, regulator 23 with reference element 24, block 25 comparison of current value of mass and setpoint 26 mass material in the bunker .re batcher, as well as the setting device 27 mass flow the output of which is connected to one of the inputs of the algebraic adder 21 and through the switch 22 to the input of the integrator 19, the output of which is connected to one of the inputs of the algebraic adder 20, the second input of which is connected to the input of the control unit 4 signals. The output of the algebraic adder 20 through the switch .22 is connected to one of the inputs of the comparison element 24 of the controller 23, the second input of which through the switch 22 is connected to the output of the material mass setting device 26 and the second input of the signal comparison unit 25. At the same time, the output of the latter is connected to the control input of the switch 22, the second input of the algebraic adder 21 is connected to the output of the controller 23, and the output of the algebraic adder 21 is connected to the output of the control unit 4, the dosing material from the bunker 2 is fed to the production line by pod feeder I, whose rotational speed is proportional to the magnitude of the signal taken from the output of control unit 4. The latter, on the basis of information received at its input from the block 7 for calculating the current mass value, measured by the weighing unit 3, generates a control signal that enters the input of the feeder 1 through the yci power slider 5 and ensures that the current mass flow value is equal of the material being dispensed at the dispenser outlet for its value in the control unit 4, which operates in the following way. As the material leaves the bunker 2, the signal from the output of the calculating unit 7 decreases even if the signals from the output of the unit 7 and the task 26 of the material mass in the bunker are equal, the comparator unit 25 is triggered, giving a command to the control input of the switch 22. The last connects the output of the mass flow setting unit 27 to the input of the integrator 19, the output of the algebraic CZ / mater 20 to the first input of the control comparison element 24, 23, the output of the material mass setting generator 26 to the second input: the comparison control element 24. one day, the accumulator 20 summs the signals, which are proportional to the mass of the material to be dispensed by the dispenser during the time interval from the moment the mass of the material in the bunker 2 sets to its specified value by the unit 26 to the current time, and to the mass of the material remaining in the bunker 2. When the current values of the mass flow rate of the dosing. material at the dispenser outlet from; given its value by the setting device 27, at the output of the comparison element 24, an error signal is formed, proportional to the algebraic sum of the signals taken from the outputs of the integrator 19, block 7 and the setting device 26. The error signal from the output of the comparison element 24 is processed by the controller 23, while the output of the controller 23 a corrective action is generated, which is algebraically summed by the adder 21 with the signal taken from the output of the mass flow setting device 27 and fed to the output of the control-, laziness block 4 and then through the power amplifier 5 to the feeder input 1, thus eliminating the deviation of the output value of the flow rate of the dispenser from its predetermined value by the setting device 27. The dependence of the measurement result on the mass of the material on the instability of the transmission coefficient of the force-measuring elements 8 and 9 and on the variation of the gravitational field of the Earth at its various points is eliminated by implementing the following measurement procedure and an algorithm for processing the signals taken from the outputs of the force-measuring elements 8 and 9 by a block 7 for calculating the current mass value. On the pre-loaded loading platform 10 with a reference mass I1, a measured mass is applied through the lever mechanism b. S11pa, due to the reference and measured by the masses, cause a change in the parameters of sensitive elements and a change in signals from the 51 output of the force-measuring elements 8 and 9, which go to the first and second input of the calculation unit 7 and then to the Plus and Minus inputs of the algebraic adders 12 and 13. On The output of the latter is generated by signals proportional to the corresponding algebraic sum and algebraic difference signals of the force-measuring elements 8 and 9, which are fed to the first and second inputs of the division block 16. On the output of dividing unit 16, a signal is formed that is proportional to the value of the quotient of the divided signals taken from the outputs of algebraic adders 12 and 13, which is fed to the Plus input of the algebraic adder 14. The input from the first output of the setpoint generator 17 is received these signals. The signal from the output of the algebraic adder 14 is fed to the first input of the I8 multiplication unit, the second input of which receives a signal from the second output of the setpoint generator 17, which is proportional to the magnitude of the reference mass. The output signal from the multiplication unit 18, proportional to the measured mass, is fed to the Plus input of the algebraic adder 15, the Minus input of which receives a signal from the third output of the setpoint generator 17 of the permanent signals, proportional to the tare mass of the feeder 1 and the hopper of the dispenser 2. The signal from the algebraic output adder 15 is fed to the output of block 7 for calculating the current mass value. Thus, the latter implements the signal processing algorithm for measuring the mass, which excludes the influence of the instability of the transfer coefficient of the measuring-element elements 8 and 9 and variations of the gravitational field of the Earth at various points while maintaining speed. This algorithm can be written as follows t „F--. - a) b.sh, 1-de g the current value of the mass of material in the hopper 2 of the dispenser; tarn massapitatel 1 and hopper 2 dispenser; the signal taken from the output of the load element B; 8 signal taken from the output of the load element 9; reference mass; when a measured load is applied to the load-receiving platform at a point equidistant from the supports on the force-measuring elements. Claims 1. A continuous dispenser comprising a hopper feeder, a weighing unit and a control unit, the output of which is connected to a feeder through a power amplifier, characterized in that, in order to improve accuracy by eliminating the component of the load element , a lever mechanism is introduced into it, the input of which is mechanically connected with the feeder, and the output is connected with the input of the weight measuring unit; the unit for calculating the current value of the material mass in the bunker, the first and second inputs of which are connected respectively to the first and second outputs of the weighing unit, and the output of the unit calculating the current value of the mass of material in the bunker is connected to the input of the control unit, while the weighing unit is executed in the form of a load receiving beam supported by two load elements and mechanically connected to the lever mechanism at a point located between its supports, and the reference mass located on the cantilever section of the load-receiving beam. 2. A dispenser according to Claim 1, of which it is, and that the unit for calculating the current value of the mass of material in the bunker is made in the form of four algebraic adders, division and multiplication units and a set of constant signals, while . the first and second algebraic adders are pairwise connected and form the first and second inputs of the unit calculating the current value to the masses of material in the bunker, the output of the first algebraic adder is connected to the input divisible, and the output of the second algebraic cyivjMaTopa to the input of the Divider divider of the division, output to