Structure-borne Sound Testing of Pump Units
Task and Process
The system described here serves to test the structure-borne noise of air pumps that are used to inflate massage cushions inside car seats.
The pump is driven by an electric motor and vibrates slightly when operated, which in turn creates noise. For reasons of comfort inside the car it is necessary to keep the noise level to a minimum. Parts that have unacceptable noise levels, e.g. due to production errors, can be identified and sorted by means of a structure-borne noise test.
The system is designed as a manual workplace. In this process, the part is inserted manually, and is then affixed and adapted. After this the actual test process starts. The structure-borne sensor is automatically placed onto the part surface and records the structure-borne noise in the previously defined frequency bands when the pump is driven. If the values lie outside the defined limits, the operator removes the part after the test and puts it to one side. In the case of non-conforming parts, the lock of the part holder remains closed until the operator presses a confirm button. This ensures that nonconforming parts are sorted out securely.
FFT analysis (Fast Fourier Transformation):
eight freely selectable frequency bands
Test time:
Depends on the defined parameters
