RU1771971C - Table vibrator - Google Patents

Abstract

Use: in the manufacture of concrete and reinforced concrete products in enterprises of the construction industry. SUMMARY OF THE INVENTION: a vibrating platform comprises movable frames mounted on a base on elastic supports in parallel. At their ends, vibrators and elastic elements are fixed, on which the bottom is supported by a form. The bottom of the mold is equipped with anvils in contact with the elastic elements of the movable frames. The contacting surfaces of the anvils and elastic elements are made inclined to the longitudinal axis of the frames at an angle of 10-45 °, and the stiffness of the elastic elements is 7-10 times greater than the stiffness of the elastic supports. 4 ill.

Description

The invention relates to the production of concrete and reinforced concrete products and can be used in construction industry enterprises.

A device for attaching a mold to a vibrating platform is known, comprising at least one fixture mounted on a movable frame of the latter with an elastic chamber connected to a pressure source with supporting platforms, the upper part of which is placed in the mounting rib of the mold with inclined working surfaces.

However, this device does not provide processing of the concrete mixture by a vibro-shock method.

Closest to the technical essence of the claimed invention is a vibrating platform for molding products from concrete mixtures, comprising mounted on the base by means of elastic supports and parallel mounted movable frames with vibrators and elastic elements fixed to their ends, on which the bottom is supported by the mold.

The disadvantages of the known solution are the reduction in the level of mold vibration due to friction losses on the stops fixed on the base at the sides of the mold to prevent it from sliding off the vibrating plate, which affects the duration of the molding process, as well as insufficient vibration processing of the concrete mixture with a vertical character fluctuations.

The purpose of the invention is to improve the quality of products.

This goal is achieved by the fact that at the vibrating platform for molding products from concrete mixtures containing mounted on the base by means of elastic supports and parallel mounted movable frames with vibrators and elastic elements fixed at their ends, by 8%

The bottom is supported by a mold, the latter is equipped with anvils fixed on its bottom and in contact with the elastic elements of the moving frames, while the contacting surfaces of the anvils and elastic elements are made inclined to the longitudinal axis of the frames at an angle of 10-45 °, and the stiffness of the elastic elements is greater than the stiffness of the elastic supports 7-10 times.

In figure 1. Depicts the vibration platform shock, VMD | plan; figure 2 - gap AA "in figure 1, the gibibrosting is torn from the mold; see, 3, also, the vibrating table at the time of impact on the displaced shape; figure 4 - aibro-site, side view.

The vibrating platform of shock action consists of several movable frames 1 mounted on a base 2 mounted on a foundation 3. Each frame 1 is a beam 4, at the ends of which electromechanical vibrators 5 are fixed from below, and elastic elements b are installed on top, which are in contact with hard anvils 7, fixed symmetrically to the longitudinal axis on the bottom 8 of the mold 9 mounted on the vibrating platform with a concrete mixture 10.

The working surface 11 and, accordingly, the anvil 7 and the elastic elements 6 are inclined to the longitudinal axis of the movable frames 1 and form 9.

The angle of inclination of the working surfaces 11 and 12 is selected depending on the predetermined nature of the oscillations of the mold 9 and lies within the limits defined for the upper limit by the need to obtain a vertical component of the oscillation amplitude of at least 0.5 mm, which ensures the separation of the mold 9 from the vibrating plate, which is at a nominal amplitude of its oscillations of 0.7 mm, applied normal to the working surface 11 of the anvil 7, arc the cosine of the angle between the directions of these amplitudes, or the same arc the cosine of the angle of inclination of the anvil to

horizon, i.e. arc cos 45 °.

The lower limit of the angle of inclination of these working surfaces is selected taking into account the elasticity of the elements and friction forces and adhesion between them and the anvil 7 and is within the angle of 10 °.

On the base 2, movable frames 1 are mounted on elastic supports 14.

Due to the large area of their contact with the working surfaces 11 of the anvils 7, the elastic elements 6 have considerable rigidity.

Based on the well-known condition of self-synchronization and ensuring the stability of periodic oscillations of the frame 1. the ratio of the elastic coefficients of the upper and lower rubber supports (limiters) for a movable frame moving down along with the mold is 1.5-2. Considering the fact that in the considered solution the frame 1 moves downward with a separation from the mold, and its mass is selected so that it is 4-5 times less than its total mass with the mold, it is required to reduce the elastic stiffness by the same amount of times supports 14. Therefore, the ratio of the stiffness of the elastic elements b to the stiffness of these supports 14 will be 7-10.

5 Vibration platform works as follows.

Form 9 with concrete mixture 10 is mounted on a vibrating platform so that its anvils 7 are light on elastic elements 6 of movable frames 1. Then vibrators 5 are turned on.

On each frame 1, when the vibrations of the vibrators 5 are rotated in different directions and the stiffness ratio between the elastic elements 6 and the elastic supports 14 is ensured, their self-synchronization occurs. Beams 4 begin to make vertical vibrations together with form I-form 9.

In this case, each frame 1. as a key, 0 periodically breaks away when moving down (in the direction of the arrow) from form 9, and then, when moving up (in the direction of the arrow), hits its anvil with its elastic elements b.

With the periodic nature of these impacts and under the influence of vibrations, the form 9 is not fixed on the vibrating plate and tends to shift from it to the side.

When the form 9 is displaced relative to the frame 1 to the right when the beam 4 moves upward, the elastic element hits the working surface 11 of the right anvil of the 7 form and transfers the impact energy to the RSU. At this time, between the left elastic element b and the anvil oppozite 7, there is a gap 5.

Due to the fact that faces 11 and 12, respectively, of the anvil 7 and the elastic element 6 have slopes towards the longitudinal axis of the e-plate, the impact force Q decomposes 0 into two components: the vertical Pb and the horizontal Pg directed towards this longitudinal axis.

This force tends to return form 9 to its original position. At the same time, this 5 force creates a horizontal component that improves the vibration processing of the concrete mix 10 in mold 9.

Thus, under the influence of horizontal shock components from the impact force of the movable frames 1, form 9

self-centered on the vibrating platform. There is no need to use stops placed on the foundation along the longitudinal sides of the mold 9 to prevent it from sliding off the vibration plate and the vibrational energy lost due to friction of the mold 9 on these supports.

At the same time, the compaction of the concrete mixture in the mold is improved by working through its volumetric vibration.

It is possible to use more rigid concrete mixtures in the manufacture of concrete products, which leads to a reduction in cement consumption.

At the same time, the wear of the molds that previously occurred during friction and their collision with the locking stops is reduced.

Formula and Vibration platform for molding products from concrete mixtures, containing mounted on the base by

elastic supports and movable frames placed in parallel with vibrators and elastic elements fixed at their ends, on which the bottom is supported by a form, which means that, for the purpose

0 to improve the quality of products, the mold is equipped with anvils fixed on its bottom in contact with the elastic elements of the moving frames, while the contacting surfaces of the anvils and elastic elements are made inclined to the longitudinal axes of the frames at an angle of 10-45 °, and the stiffness of the elastic elements is greater than the rigidity elastic supports 7-10 times.

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