SU1375450A1 - Table vibrator - Google Patents

Abstract

The invention relates to the manufacture of concrete products and can be used as a shaker for conducting research and testing products. The purpose of the invention is to increase compaction efficiency and reliability by reducing the dynamic loads on the exciter. For this, the rod mounted on the balancing frame of the vibration exciter is made in the form of a guy 8 connected with a tension device with an elastic element 9 mounted on the bracket of the working body 3 in contact with the balancing frame by means of shock absorbers and elastic buffer elements. A flexible, in the form of a guy-rod, a rod of excitation of oscillations, together with a working body, a disturbing impulse in one direction only, namely downwards, increases the degree of asymmetry of the vibration cycle, which contributes to a more efficient compaction of the mixtures being formed. In addition, loading the exciter with one-sided load increases the reliability of the structure. 2 Il. Video e cl

Description

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four

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The invention relates to the manufacture of products from concrete and reinforced concrete, in particular to devices for vibroplating materials, and can be used as a shaker for carrying out research and testing products.

The purpose of the invention is to increase the compaction efficiency and reliability by reducing the dynamic loads on the exciter.

FIG. schematically shows the proposed vibro-shock platform, general view; in fig. 2 is a view A of FIG. one.

The platform consists of the working body 3 installed on the base 1 by means of elastic elements 2 and a balancing frame 4, connected by shock absorbers 5 and contacting each other by means of elastic buffer elements 6. A curviline oscillator 7 oscillations fixed to the balancing frame 4 by means of a rod in the form of a guy 8 with an elastic element 9 mounted on the arm of the working body 3. The guy 8 is provided with a tensioning device, which consists of a fork 10 with a screw shank and a nut 11.

To ensure stable operation of the platform with maximum asymmetry of the vibration cycle and minimum load on the shaft and bearings of the vibration exciter, the cable 8 is tightened by compressing the elastic element 9 by rotating the nut 11. In this case, the strain of the elastic element should be minimal but sufficient to ensure constant tension, since otherwise additional jerks in the shatun lead to a reduction in the asymmetry of the vibration cycle and an increase in the dynamic loads on the bearings and the exciter shaft oscillates This reduces the compaction efficiency and reliability. The optimum amount of deformation of the elastic element 9 at a given mode of impulsive action on the formable mixture is determined by the formula

dNo to (A | + A2 d-f Ah |), where to 1.1 -1.5;

AI is the absolute value of the oscillation amplitude of the working body;

A2 - the absolute value of the oscillation amplitude of the balancing frame;

d - dynamic displacement of the center of oscillations of the working body; Ahi - deformation of shock absorbers and elastic buffer elements under the action of the weight of the form with a moldable mixture

RFRF

t P

Ahi

with him

R

Sa

five

15 0 5

About 5

five

0

five

where e is the gap between the working body and the elastic buffer elements; RF - form weight - with a moldable mixture; Ca-total stiffness of shock absorbers;

Sat-total stiffness of elastic buffer elements.

Vibro shock platform works as follows.

A form with a concrete mixture is installed on the working body 3, then the crank exciter 7 oscillations are turned on. During one rotation of the shaft in the first half-period the crank does not have the connecting rod 8 down and informs the counter-movement of the working body 3 and the balancing frame 4, compressing the shock absorbers 5. In the subsequent half-period, the tension of the connecting rod decreases and the shock absorbers 5 inform the working body 3 and the balancing frame 4 in opposite directions. Thus, their vertical oscillations appear in the counterphase. When this occurs, the impact of the working body 3 with mounted on the balancing frame of the elastic buffer elements 6, which causes the asymmetry of the vibration cycle. Since the vibration rod exciter 7 is made in the form of a flexible guy working only for tension, and the disturbing power pulses of the vibration exciter are communicated to oscillating masses (working element 3 and the balancing frame 4) only when they move in opposite directions, the asymmetry of the vibration cycle increases and the number of cycles the loading of the shaft and the bearings of the vibration exciter is reduced. This contributes to the reliability and efficiency of the compaction of the moldable mixtures.

When changing the technological parameters of the molding (the weight of the mold with the shape of my mixture, the characteristics of the mixture, etc.), the optimum amount of deformation of the elastic element 9 is established by rotating the nut 11.

Claims (1)

Invention Formula Vibro-shock, platform containing working body installed on the base and connected to each other by means of coaxial elastic elements and shock absorbers working body and balancing frame, in contact with each other by means of elastic buffer elements, and a curved stimulus of oscillation with an elastic element in the connecting rod on the balancing frame characterized in that, in order to increase compaction efficiency and reliability by reducing dynamic loads on the exciter, the bar of the latter is made in the form of a van the one connected at one end by means of a tension device with an elastic element, the magnitude of the deformation of which at a given mode of impulse action on the concrete mixture is dNo to (A | + A2- d + Ahi), where k 1,1 - 1,5; D | - absolute amplitude value oscillations of the working body; A2 is the absolute value of the oscillation amplitude of the balancing frame; d is the dynamic center of the vibrations of the working body; Aht - deformation of shock absorbers and elastic buffer elements under the action of the weight of the form with a moldable mixture RFF sr pr-sg L | 0 the gap between the working body and the elastic buffer elements; mold weight with a moldable mixture; total stiffness of shock absorbers; total stiffness of elastic buffer elements.