Swing table
A vibrating table (also vibrating table or English Shaker ) is a technical checking device , with which by vibration component or whole machine is charged.
application
The vibrating table mostly generates harmonic vibrations , but other signal forms are also possible. The evaluation of several force and acceleration sensors provides information about the deformation and natural frequencies of the test object.
A vibrating table can be used for. B. use for the compaction of concrete or bulk materials. Likewise, on a vibrating table z. B. Check electromechanical or electronic components for their vibration resistance. Often shaking tables / vibration systems are integrated into existing systems in order to compress or distribute products. Some of the diverse areas of application are exemplified: Compaction of concrete and precast concrete elements, compaction of polymer concrete (mineral cast) for machine beds and machine frames, venting of viscous media such. B. resins, 2-component mixtures, compression of loose bulk materials z. B. when filling in packaging, big bags, gabions, etc. emptying of containers, testing of electrical and mechanical components for vibration resistance, compression to determine soil parameters according to DIN, venting of viscous liquids.
In acoustics and vibration technology, electrodynamic vibration tables are used for the targeted vibration or structure-borne sound excitation of measurement setups. Here, exact signal curves can be presented over a wide frequency spectrum. A special form of such vibrating tables are vibration calibrators, which are used to calibrate structure-borne sound or vibration sensors.
Depending on the application, the movement introduced into the vibrating table top can take place in different forms:
Directed vibration
Classically, the swinging movement is directed and perpendicular to the table surface. In most cases of application, an optimal result is achieved here. Piston vibrators, which can generate a directed vibration, can be used to generate this movement in pneumatic operation. Unbalance motors are used in an electrically operated vibrating table. Since they have a rotating force vector due to their design, two such units must be used. These are arranged axially parallel and are operated in opposite directions, which results in self-synchronization. As a result, the force components cancel each other out in the plane of the table, creating the desired sinusoidal oscillation perpendicular to the table top.
In vibration measurement technology, electrodynamic vibration tables are usually used. Similar to an electrodynamic loudspeaker , these are driven by a voice coil in a magnetic field.
Revolving vibration
In simple applications, a rotating oscillation can be sufficient. Both electric unbalance motors and pneumatic ball, roller or turbine vibrators (for smaller vibrating tables) can be used.