SU548766A1 - Method of volume and weight dosing of mixture components - Google Patents

Description

one

The invention relates to the field of volume-weighted dosing of substances to be mixed, in particular, to methods for preparing a mixture of a given volume mass of concrete based on lightweight aggregates, for example, expanded clay, whose bulk weight varies over a wide range. Fluctuations in the volumetric weight of the aggregates result in fluctuations in the volumetric weight and the concrete mixture itself.

Methods are known for metering mixture components by maintaining their weight ratio of 1-5.

The closest in essence to the invention is the method of volume-weight dosing of the components of the mixture by continuous volume control of the components.

The known method of volume and weight dosing does not provide the required accuracy and its implementation requires a complex regulating device. At the input of a regulator in a device for implementing a known method, disturbing influences from sensors of bulk bulk mass of large and small components are applied. These disturbances can lead to an unstable regulation mode. In addition, when dosing in a known manner, it is difficult to adjust the process.

The purpose of the invention is to improve the accuracy and simplify the process of adjusting the dosage.

This is achieved by using the proposed method, the volumetric flow rate of each component is controlled autonomously by means of functional transducers;

The volumetric mass of the mixture YCM in the established state, taking into account the coefficient p of the decrease in the volume of the mixture, can be written

 ktkmtm

(one)

S (UK + s)

where YCM is about mass of the mixture;

VK is the volume of the coarse fraction;

MIND - the volume of the fine fraction;

7i is the bulk volume of the coarse fraction;

7 m - bulk bulk density of the fines fraction;

Claims (4)

P is the coefficient of a decrease in the volume of the mixture compared to the sum of the volumes of the liquidate. From the expression (1) ..,. TM RTM, k - m j ;; : -Tsm 7k y - “Mkq Tm PTsm , like (VM) taking into account the coefficient p Tm.n UM MIND (m PTsm. Similarly for a large fraction of Tcm Tk.N UK UK.N. Dosing of each component is made only depending on its bulk density. This eliminates the need for cross-links and makes The process of adjusting the mix ratio is sustainable. Independent regulation of the volumetric efficiency of each The dosing unit allows convenient setting of the dosing process. Accounting for the dosing algorithms (5) and (6) of the reduction ratio of the mixture volume makes it possible to more accurately stabilize the bulk mass of the mixture. , makes it possible to obtain a constant instantaneous value of the bulk mass of the mixture and control the dosing process according to the total weight of the mixture. In the drawing, a block diagram of an apparatus for carrying out the method of volume-and-weight dosing of the mixture is shown. The fine fraction is dosed by the metering device 1, in which the sensor 2 of the bulk density, the main drive 3, the servomotor 4, the sensor 5 of the instantaneous consumption of material, the functional converter 6 and the regulator 7 perform the algorithm in accordance with distribution (5). The coarse fraction is dosed out by the metering unit 8, in which the bulk mass sensor 9, the main drive 10, the servo motor 11, the instantaneous volumetric flow sensor 12, the functional transducer 13 and the regulator 14 perform the algorithms in accordance with expression (6). The control of the dosing process is carried out according to the signal of the strain gauges 15 through the secondary device 16 and the magnetic starters 17, affecting the main drives 3 and 10 of the metering devices 1 and 8. The dosing according to the method is carried out as follows. By means of the positioning regulator included in the secondary device 16, the required weight dose of the mixture is established. Dispensers of small and large fractions are included simultaneously. The variable value of the bulk filler mass is sensed by sensor 2 of bulk mass, the signal of which is connected to functional converter 6. Fupcion converter 6 generates a signal in accordance with the expression (5) and out of balance the regulator 7. Servomotor 4 changes the speed of the main drive 3 the metering device, and the feedback signal of the sensor 5 balances the signal of the regulator 7. Similarly, the volume control of the metering unit 8 of the bulk fraction occurs. The presence of functional transducers 6 and 13, which perform algorithms (5) and (6), provides a constant value of the instantaneous volumetric mass of the mixture, which allows controlling the process of dosing the signal of strain gauges 15, on which capacitance 18 is fitted. weight dosing of the components of the mixture by continuous volumetric adjustment of the components, characterized in that, in order to increase the accuracy and simplify the adjustment process, the volumetric flow rate of each component is controlled autonomously by m functional transducers volumetric mass — volumetric flow rate so that the instantaneous value of the volumetric mass of the mixture remains constant, and the end of the dosing process is carried out until the specified mass of the mixture is reached. Sources of information taken into account during the examination:. Auth. St. No. 334487, cl. G Olg 13/28, 1970. 2. Avt. St. Afc 398833, cl. G Olg 19/22, 1972. 3. Pateit USA N 3125172, cl. 177-80, 1964. 4. US patent number 3173505, cl. 177-70, 1965. b. Carpias E. B. Automation equipment for measuring and metering mass. M., “Mechanical Engineering, 1971, p. 100-250. 6. Auto. St. No. 436332, cl. G Olg 19/32, 1972.