SU1096119A1 - Method of automatic control of placing of concrete mix and loose materials - Google Patents

Abstract

METHOD FOR AUTOMATIC CONTROL OF CONSTRUCTION OF CONCRETE MIXTURE AND BULK MATERIALS, including stabilization of the required ratio of concrete flow to feed speed of the feeder by changing the speed of the feeder, in that the actual weight of the concrete mix is measured and movement of the feeder, change the feed rate of the concrete mix and adjust the speed of movement of the feeder, and changing the feed rate of the concrete mix is carried out t of formula U, (A5) -flVj, a feeder driving speed correction is performed according to the formula V Z-

Description

The invention relates to the construction and can be used for automatic control of devices for laying concrete mix, bulk materials, etc.

There is a known method of automatically controlling a device for laying a concrete mix, which consists in maintaining the required ratio of the flow rate of the concrete mix to the speed of the feed, the controlled speed of the electric drive of the screw feeder, taking into account the speed of movement of the cart with the form, the speed of movement of the horizontal conveyor belt, receiving the concrete mix from the screw feeder as well as the degree of filling of the feed bin P1.

The disadvantage of this method is that it can be used only for devices for forming long articles of simple configuration located on a moving carriage.

In addition, the method is characterized by the accuracy of the installation, since the regulation is not made according to the actual form filling.

Closest to the present invention is a method for automatically controlling the laying of a concrete mix and bulk materials, including stabilizing the required ratio of the flow rate of the concrete mix to the speed of movement of the feeder by varying the speed of movement of the feeder 2.

The disadvantages of this method are low accuracy and speed of adjustment, since there is no adjustment of the speed of movement depending on the mismatch of the weight of the concrete mix, actually laid in the form, and the intensity of the feed depending on the mismatch of speed.

In addition, it is impossible to lay the concrete mix in a form of complex configuration or molding of multilayer products (forms, panels with window or door openings, etc.), since this requires complex movement of the feeder relative to the shape and regulation of the speed of movement of the feeder as a function of the error while maintaining the desired ratio of the intensity of the mixture to the speed of movement.

The purpose of the invention is to improve the accuracy of the control.

This goal is achieved by the fact that according to the method of automatically controlling the laying of the concrete mix and bulk materials, including stabilizing the required ratio of the flow rate of the concrete mix to the speed of the feeder, by changing the motion speed of the feeder, the actual weight of the concrete mix in the shape and actual path of the feeder is measured. the feed rate of the concrete mix and adjust the speed of movement of the feeder, and 5 change the feed rate of the concrete mix is carried out according to the formula

(45) -4V, and feed speed correction

carried out according to the formula

V.i-fop pK dt Ф pacMJ

5. where K F (S);

S is the density of the concrete mix; F (S) is the cross section of the form; RF - actual mass of concrete

in the shape of; Rrasch - the calculated mass of the concrete mix;

V (iis) - set the speed of movement of the feeder as a function of the difference between the specified and the actual by moving the feeder 35;

dM is the difference between the target and actual speeds of the feeder. The method is carried out as follows. The mass of the concrete mix that entered the form during time i can be represented in

:.,

where and - intensiveUc3t

f

the form

ness of concrete supply (consumption).

The required mass of the mixture for filling the formivQii can be represented as 8

Ppac - V y F (50-rSpf5} d5.

The condition for the accuracy of the process of laying the mixture over the cross section of the form is equality

and

. (Pp "s.) G ((1 Thus, the control task with 45 predetermined trajectories of movement

(S I (-fc), density (-jr) and the coefficient K-yF (S} is ensuring equality at maximum speed due to the interconnected operation of the concrete mix feed drive and the feeder displacement drives.

The concrete supply unit at the beginning of the process is described by a delayed link (the delay time is a random variable depending on the initial state of the concrete line and the speed of the mixture movement), there may also be discontinuities in the continuity of the mixture, therefore the control channel should be used as a reference channel supply the concrete mix and form a controlling effect on the drive of the movement of the feeder as a function of the intensity of the supply of the concrete mix and the coefficient K in the form of Uj ifts / K. In order to accurately position the feeder relative to the shape in acceleration modes, deceleration, the speed of movement of the feeder must change with constant acceleration, i.e. + Ei The path and speed when -cori5-t are related to the contingency of 5 v2 / 26, whence V VSne-K V5 Drive of the feed unit at 5p: 45, L52.5 .- (distance traveled; lb - mismatch along the path; SP, 5 .G, respectively, the acceleration, deceleration path) is in saturation mode, i.e. Works with maximum performance. With a change in jump Vj due to mechanical inertia, the speed of movement of the feeder in a jump cannot change and, according to the condition of optimal operation of the mechanism, must change linearly with constant acceleration. Aop Error on the speed / jV V j. (Vpj. Is the feedback speed measured by the speed sensor) leads to accumulation of the mismatch in weight of the LR Raschat RF where Rf is the actual (measured) value of the weight of the concrete mix laid in the form. The astatism of the system with respect to the set value of the Rrasch weight can be ensured by introducing a correction of the velocity of the feeder as a function of the weight mismatch. It is easy to show that (RRFR) is canceled, and to obtain astatism by weight it is necessary to adjust the speed by the value - 3ldi: x (P.) Thus, the control effect on the drive of the movement of the feeder (.C4) In transient modes when Vj changes abruptly, the speed is It does not cause U / V K conditions to be met, which leads to uneven packing of the mixture over the cross section of the form.In transient conditions, the U / V-K condition can be ensured by introducing feedback on the mismatch of the DM into the drive control channel of the concrete supply unit. The movement of the feeder in acceleration modes, deceleration must be in the form of. The actual value of the mixture supply unit is setting, therefore the mixture supply drive should form a control action (th 5). Taking into account the condition U / V k and input feedback for the speed error, & I ke, we get (A51 -4V. 9L. The drawing shows a block diagram of the paver control system that allows the proposed method to be implemented. The control system contains adder 1, regulator 2, adder 3, multiplier 4, drive 5 of the concrete mixture supply unit, sensor 6 races Concrete mix, weight unit 7, adder 8, differentiating element 9, adder 10, divider II, adder 12, controller 13, actuator moving actuator 14, feeder 15, speed sensor 16, displacing 17, computing unit 18, determining the required mass of the concrete mixture depending on the cross section of the shape or part of it, the density of the mixture and the position of the feeder relative to the form (50 form (50 n coefficient K, dependent on the cross section of the form and density of the concrete mix. At the adder 1, the displacement of the feeder 5c is specified, and at the supervisory unit 18, the density of the concrete mixture y and the dependence of the cross section F (Si) of the form or its part on the path are specified. The adder 1 determines the mismatch d5 | 5j-Sj, j, where Sc, the actual position of the feeder, as determined by displacement transducer 17. The position 2 regulator feeds the adder 3 speed signal of the feeder to mismatch VV (5, which performs operation V ( A5) -lV V. A multiplier 4 multiplies the signal U by a factor K determined by the computing unit 18. The signal from the output of the stranger 4 and K (l5) is D V. It is fed to the drive 5 of the concrete supply unit of the concrete mixture. ) 6 concrete mix gives a signal to the sum Ator 10. The weighing device 7 determines the actual mass of the concrete mix Rf in a form that is compared in the adder 8 with the calculated mass determined by the computing unit 18. The difference signal D P Rrasch f of the output of the adder 8 is differentiated by element 9, i.e. the & U value. The adder 10 determines the value of and which is multiplied by the value of 1 / K. the divider. The signal (if-4 and) / K at the output of the divider 11 is equal to the required movement speed of the feeder 15. In the adder 12, the speed of reference is compared to the actual speed feeder issued a speed sensor 16, and a received error signal L rV, -V-jg is applied to the speed controller 13 of the drive 14 of the movement of the feeder and to the adder 3.

Thus, the automatic control system maintains precisely the ratio and / and K due to the interconnected control of the concrete supply drive and the feed motion drive 14 in static and dynamic modes. When speed mismatch occurs, the AV system compensates for the resulting deviation by a proportional effect on the feed drive 5 through the adder 3 and multiplier 4 and on the displacement drive 14. On the occurrence of the 4P weight discrepancy, the feed speed of the feeder is automatically corrected. The system is astatic with respect to the weight of the concrete mix to be placed in the mold and with respect to the path of movement of the 1 stattel relative to the mold.

The implementation of the proposed method makes it possible to fully automate the operation of laying the concrete mix in the form of a complex configuration with high accuracy and maximum speed, as well as to eliminate the loss of the concrete mix and reduce the time lost in processing the upper surface of the molded product.

Claims (2)

METHOD FOR AUTOMATIC CONTROL OF LAYING CONCRETE MIX AND BULK MATERIALS, including stabilization of the required ratio of the intensity of concrete supply to the speed of the feeder by changing the speed of the feeder, characterized in that, in order to improve the accuracy of control, measure the actual mass of concrete in the form and the actual path of the feeder, change the feed rate of the concrete mixture and adjust the speed of the feeder, and the change in the feed rate of the concrete is carried out by the formula U ^ K [VUS) -AV], and the correction of the speed of the feeder is carried out according to the formula v - ± _sL 3 “K dt j is the density of the concrete mixture; G (5) is the cross section of the form; Rf is the actual mass of concrete in the mold; Rrash ^{- the} estimated mass of the concrete mixture; H (d5) - the set speed of the feeder as a function of the difference between the set and the actual way of moving the feeder D5; Δ V is the difference between the given and actual speeds of the feeder. ΐ