SU1313525A1 - Vibrating screen - Google Patents

Abstract

The invention relates to a technique for the classification of bulk materials (M) by size and improves the quality of screening due to the even distribution of M over the area of the sieve. The screen includes a spring-loaded box 1, an exciter 4, a sieve 3. A distribution grid (PP) 5 2 is installed above the sieve 3 As a set of grate elements (CE) installed along the sieve 3 from the side of the loading end with the possibility of oscillations. The horizontal component of the oscillation amplitude is directed across the sieve 3. The holes of the PP 5 (the distance between the elements) exceed the size of the holes of the sieve 3. Moreover, the CE can be. made in the form of rods, the supporting ends of which are eccentric relative to the axis of the rods. Unbalanced masses of the rods are oriented in different directions relative to the longitudinal axis of the RR 5. Also, CE can be. made in the form of elastic bands with protrusions on the side surface, oriented in different directions relative to the longitudinal axis of the PP 5. Additional vibratory action is reported due to the vibrations of the upper layers of the upper layer M. When this happens, segregation of M is more intense and its additional movement across the sieve. 2 hp f-ly, 9 ill. (From sl cobalt tsS Oi

Description

The invention relates to a technique for the classification of bulk materials by size and can be used in the building materials industry, in the metallurgical industry, as well as in other industries.

The aim of the invention is to improve the quality of screening due to uniform distribution of the material throughout the screen area.

FIG. 1 shows a vibrating screen, a longitudinal section; in fig. 2 is a section A-A in FIG. one; in fig. 3 - crash, cross section (variant); in fig. 4 is a view B in FIG. 3 (in the place of loading screen); in fig. 5 - crash, cross section (variant); in fig. 6 is a view of B in FIG. 5 (in the place of loading screen); in fig. 7 is a diagram of the vibration force vectors in the longitudinal section of the screen; in fig. 8 - section GG in FIG. 7; in fig. 9 is a section DD in FIG. 7

The vibrating screen contains a duct 1 mounted on springs 2, a sieve 3 and a vibration exciter 4. A distributor grid 5 is installed above the sieve from the loading end on the length f, made in the form of a set of grate elements 6 oriented along the sieve from its loading end. The holes d of the lattice (the distance between the elements) exceed the size of the holes d of the sieve 3. The grate elements 6 are mounted with the possibility of spatial oscillations relative to the sieve 3, with the horizontal component of their oscillation amplitudes dc directed across the sieve, which can be realized by one of the device designs.

Example 1 (Fig. 1 and 2). The grate elements 6 are attached by ends to the cross-beams 7 and 8, rigidly connected to the frame 9, which is connected to the box 1 by means of elastic links 10. On the longitudinal sides of the frame 9 are installed exciters 11, the direction of rotation of which is chosen depending on the desired trajectory of movement of elements 6 Horizontal lateral stiffness C — y of elastic bonds 10 of the adopted MeHbuje stiffness C (relative to the OX axis) and vertical stiffness Cr, i.e. Su-S and. Elastic bond 10 may be made of a strip of sheet rubber, for example, a conveyor belt with a direction of cord threads that is coaxial with respect to the axis OZ.

To prevent jamming of large pieces of material on the sieve 3, the angle of inclination o (, i of the elements 6 in the direction of transporting the material is less than the angle of inclination o (. Sieve 3, and the distance h between the elements and the sieve at the loading end

Yes, it is taken from the relationship, where d is the minimum size of the screen openings. The largest size of a piece of shaken material should be no more than 5d.

Example 2 (Fig. 3 and 4). The grate elements are made in the form of rods 12 with ends 13 eccentric with respect to the axis of the rods, which are fixed by means of elastic liners 14 on cross-pieces 7 and 8 rigidly connected to the duct 1. In this case the rods 12 are oriented with unbalanced masses (eccentricity G) in different directions relative to the longitudinal axis of the lattice (axis OX sieve). The trajectory of shuffling, rods of rods relative to the sieve is due to the ratio of horizontal and vertical stiffness of the elastic liner 14.

Example 3 (Fig. 5 and 6). The grate elements are made in the form of elastic

 tapes 15, on the side surface of which protrusions 16 are located, whereby the tape is in cross section and has the shape of a figure asymmetrical about the longitudinal axis aa (eccentricity - Ei).

5 Tapes 15 are fixed in cross-pieces 7 and 8 with axial tension, providing the required natural frequency of oscillation and carrying capacity of the grid. The tabs 16 of the tape are oriented in different directions relative to the longitudinal axis of the lattice (axis

0 OH sieves). The location of the protrusions 16 only on one side of the tape 15 and the indicated orientation of them cause the asymmetry of the string relative to the vertical axis of the place of their attachment to the cross-arms and provides the possibility of additional oscillations around the longitudinal axis a-a when the box vibrates. The axial tension of the belts 15 can be adjusted by moving the crosspiece 8 along the duct 1 by the value D. In addition, tapes by

In the box 0, the width of the box can have different axial tension and, accordingly, different amplitude of displacements across the sieve with the same working length I and constant oscillation parameters of the box.

5 The roar works as follows. The source material is fed through the opening of the frame 9 and the openings d of the lattice 5 to the sieve 3. A cone of material with a height exceeding the optimum HQ value is formed under the grid. Under the action of the disturbing force of the vibration exciter 4 on the sieve 3, a field of vibration forces P is realized, uniformly distributed along the length L of the screen (Fig. 7). In this case, segregation, transportation and classification processes occur in the material layer. Their effectiveness essentially depends on the height of the layer, the optimum value of which is But with a dry classification

per unit should not exceed 4 times the value of the d hole of the sieve. When the exciters 11 are turned on, transverse oscillations of the frame 9, traverse 7 and 8, and also grate 6, resulting in the upper layers of the material at the loading point on the length I, an additional vibration effect is produced, the force field of which consists of a horizontal RS, directed across the sieve, and vertical Pc. The ratio between them is determined both by the direction of amplification of the vibration exciters 11 and by the ratio of the values of the stiffness Q, Cy and Cz of elastic connections 10. The accepted minimum value of the stiffness Cy provides the greatest displacement of the strings across the sieve with amplitude a.

Under the action of vertical pulses P ;, realized by vertical displacements of elements with amplitude a |, intensive segregation of the material occurs, as a result of which the small fractions are faster mixed through the material layer to the sieve 3. This is caused by the vibroactivation of the material in the zone the action of the power pulses P and PC due to the high relative velocity of the opposing vertical fluxes of particles. FIG. 7 and 8, this zone is h thick and F is shaded.

Horizons (gallic displacements of the elements across the sieve with amplitude a cause horizontal force impulses on the material, which is why it is additionally displaced across the sieve at length t

With the direction of horizontal power impulses in P (, in different directions from the axially longitudinal axis of the lattice (axis (SX of the sieve) (Fig. 8), an intensive distribution of the material of the cone jio irii in the sieve is provided. As a result, the length of the sieve increases on which layers of material are uniformly distributed on the area.

In the example of the device with eccentric support ends of elements fixed in elastic liners, distribution. The material in the sieve width is carried out in a similar manner. When the vibration exciter 4 is operated. The method with the sieve oscillates with an amplitude given and due to the elastic properties m of the inserts 14 an additional oscillation of the rods occurs. Due to the eccentric application of the inertial force P, the rods perform up to 0

0

Compulsive torsional vibrations, which contributes to the intense breaking of the material at the loading site.

When the grate elements are made in the form of elastic bands 15, they are oscillated when the box and traverse rigidly attached to it are moved. In this case, the relative displacements of the ribbons are due to their high elastic properties, which allows an intensive displacement of the material across the sieve without the additional vibration exciter and elastic bonds. In addition to the examples described, this design provides the ability to control

5 by the intensity of the vibration effect on the material at the loading site due to the change in axial tension. The control can be implemented by installing the crosspiece 8 with the possibility of moving it along the duct 1. When it is moved by an amount g, the working length of the string increases with axial tension. By regulating the latter, the frequency of the string oscillations is varied, and the oscillation amplitude is changed by the same.

five

Form u. and invention

0

five

I. Vibrating screen, including spring-loaded box, vibrator, sieve and distribution grid installed above the sieve, the holes of which are larger than the holes of the ciiTa, characterized in that, in order to improve the quality of screening due to uniform distribution of the material over the area of the sieve, distribute 1-on-grid is made in the form of a set of grates installed along the screen from the side of the loading end with the possibility of oscillations, horizon.1 on which the amplitude component is directed across the screen.

0 2. The screen according to claim 1, characterized in that. that the grate elements are made in the form of rods, the supporting ends of which are eccentric with respect to the oci rods, while the unbalanced masses of the rods are oriented in different directions from the longitudinal axis of the rod.

3. The screen according to claim 1, d.tchchayuschiyis.h topics. that the grates are e, -1.meites are in the form of elastic, 1ent with BbicT -iia.Mii on the side of the surface, oriented in different directions refer. 1no kind (), 1b1k1 | 1 axis of the lattice.

-X

7 /

FIG. 3 Type B

7

d7J

h2 and .5

Bui in

Fig.8

FIG. 9

Claims (3)

Claim 1. Vibrating screen, including a spring-loaded box, vibration exciter, sieve and a distribution grid mounted above the sieve, the openings of which are larger than the sieve openings, characterized in that. that, in order to improve the quality of screening due to the uniform distribution of material over the area of the sieve, the distribution grid is made in the form of a set of grate elements installed along the sieve from the loading end, with the possibility of oscillations, the horizontal component of the amplitude of which is directed across the sieve. 2. Rumble on π. 1, characterized in that. that the grate elements are made in the form of rods, the supporting ends of which are made eccentric relative to the axis of the rods, while the unbalanced mass of the rods are oriented in different directions relative to the longitudinal axis of the grating. 3. The roar of and. 1, characterized in that. that the grate elements are made in the form of elastic ribbons with protrusions on the side surface oriented in different directions relative to the longitudinal axis of the grating. Nmax (rig. 4 7 GG FIG. 8