DE102006052848A1 - Method for shaping and compressing compactable mixture, particularly concrete mixture, involves coupling vertical vibration with horizontal vibration, and excitation is carried out by horizontal excitation system - Google Patents

Abstract

The method involves coupling vertical vibration with a horizontal vibration, and the excitation is carried out by a horizontal excitation system. The coupling is so carried out that the frequency of the vertical oscillation is twice as large as the excitation frequency of the horizontal oscillation. An independent claim is also included for a device for shaping and compressing compactable mixture.

Description

The The invention relates to a method and a device for shaping and densification of compressible mixture, preferably from Concrete mixture.

State of the art

The currently often Applied vibration compression with shape excitation is done by external vibrators and with excitation frequencies between 50 Hz and 200 Hz in normal to high-frequency range. This creates a high level of noise pollution. An approach for the noise reduction in the case of vibration compression, there is work in the low-frequency Range, because the threshold of hearing for the People are very frequency dependent is.

These considerations led for so-called "shaking", being low-frequency mechanical vibrations mainly in a horizontal direction the mold is entered in the concrete quantity. This shaking technique is associated with the disadvantage that the compression effect at Precast concrete with large Thickness is insufficient. These procedures also occur at lower levels Precast concrete unevenness the concrete compaction on.

Known are solutions, where the compression with a compression system in horizontal Direction and another compression system in the vertical direction he follows.

A practiced solution is the combined vibration excitation at Vibrierstationen in pallet circulation systems. First shake horizontally at low frequencies and then vibrate vertically normal frequency ( DE 4335944 , Ebawe). The combined excitation is also used on tilting tables ( DE 4143469 , Avermann), the horizontal and vertical excitation can be done sequentially but also simultaneously. The horizontal path amplitudes are larger than the vertical ones.

Another method with simultaneous action of horizontally and vertically directed vibrations ( SU 1189683 ) is characterized by the steadily changing horizontal vibrations in the direction.

disadvantage is the method with a normal frequency vertical vibration the noise development. One Another disadvantage of the known method is that the large-area forms are bend soft in the normal frequency excitation frequency range and so on Distribution differences of the acceleration amplitude occur. These lead often to uneven concrete compaction. Furthermore, the vibration excitation with two separate exciter systems for the horizontal and vertical vibration with increased drive and control effort connected.

task

Of the Invention is based on the object with the low-frequency shake associated noise reduction and at the same time in the case of precast concrete parts of large thickness to achieve sufficient compaction.

The inventive solution of the problem consists of a compression system ( 1 ) with a vibration table ( 1 ), several warehouses ( 2 ), a horizontal pathogen system ( 3 ) and a form ( 4 ) with the concrete amount. In this compression system, a horizontal and a vertical vibration is coupled. This coupling is done so that a vertical movement with twice the frequency of the horizontal oscillation takes place. The exclusively horizontal excitation is low-frequency in the frequency range between 3 Hz and 10 Hz. The resulting from the coupling vertical vibration is thus in the range between 6 Hz and 20 Hz.

The Invention has the advantage that the combined horizontal and achieving vertical vibration with a horizontal exciter system becomes. Because both the horizontal excitement and the vertical Low frequency excitation will cause a low noise emission reached.

There the oscillation frequency of the vertical oscillation through the coupling twice as high, even at low vibration paths are sufficient Acceleration amplitudes for achieved the concrete compaction.

By the storage of the horizontally rigid vibration table on many Storage is a uniform expression of vertical vibration and thus achieved a uniform concrete compaction.

A possible embodiment shows 2 , The swinging table ( 1 ) is based on a sufficient number of eccentric bearings ( 5 ) against the ground ( 3 ) supported. The length of the eccentric is chosen so that a favorable ratio between horizontal and vertical vibration path is achieved. The deflection of the eccentric during operation is between 20 ° and 85 °. The vibration table is driven by conventional unbalance exciters or hydraulically, pneumatically or by mechanical gearboxes.

Another embodiment shows 3 , The storage of the swinging table ( 1 ) takes place here on bearing assemblies with a defined curved path ( 8th ), which produces the desired coupling between the horizontal and vertical vibration path and a cam follower ( 7 ). This bearing assembly is replaced by a return device ( 9 ), which ensures the coupling between cam track and cam follower. Due to the geometry of the curved path, the ratio between horizontal and vertical oscillation can be adapted to the requirements. The vibration excitation in the horizontal direction is carried out with conventional unbalance exciters or hydraulically, pneumatically or by mechanical transmission.

Another embodiment shows 4 , The storage of the swinging table ( 1 ) takes place here on bearing assemblies consisting of a layer of elastic rubber ( 10 ) and curved shells ( 11 ) consist. The layering creates a bearing unit which is flexible in the direction of the curvature and has a high rigidity in the transverse direction. The curvature of the steel shells produces the desired coupling between the horizontal and vertical vibration paths. By changing the curvature, the ratio between horizontal and vertical vibration amplitude can be adapted to the requirements. The vibration excitation in the horizontal direction is carried out with conventional unbalance exciters or hydraulically, pneumatically or by mechanical transmission.

In a further embodiment variant, the coupling bearings and the vibration excitation in the vibrating station of a pallet circulation system integrated.

1

vibration table

2

storage unit

3

vibratory exciter

4

forming element

5

eccentric

6

underground

7

scanning

8th

cam track

9

retractor

10

rubber layer

11

curved shell

Claims (6)

A method for shaping and compressing compactable mixture, preferably of concrete amount, on vibration tables with low-frequency horizontal vibration and low-frequency vertical vibration, characterized in that the vertical vibration is coupled to the horizontal vibration and the excitation by a horizontal exciter system. Method according to claim 1, characterized in that that the Coupling is done so that the Frequency of vertical vibration is twice as large as the excitation frequency of the horizontal vibration. Device for shaping and compacting compressible mixture, consisting of a vibration table with form elements, bearing elements and vibration exciter system, characterized in that the bearing elements couple horizontal and vertical oscillations and enter Vibration exciter system is provided in one direction. Device according to claim 3, characterized in that that the Coupling between horizontal and vertical vibration by eccentric he follows. Device according to claim 3, characterized in that that the Coupling between horizontal and vertical vibration through a Curved track takes place. Device according to claim 3, characterized in that that the Coupling between horizontal and vertical vibration through bearings from layers of rubber and curved Shells done.