Measurement apparatus for testing and calibrating bone-conduction vibrators

摘要

The invention relates to a skull simulator, which is a measurement apparatus (1) for testing and calibrating bone-conduction vibrators (25) under realistic operating conditions. In known skull simulators (1), the front wall (11) of the casing (12) - and/or exposed parts of the suspension (3, 4) - have one or more planar surfaces on the front, and these planar surfaces are thus oriented towards the bone-conduction vibrator (25) when it is mounted on the skull simulator (1). Such planar surfaces may reflect airborne sound emitted from the housing of the bone-conduction vibrator (25) or may emit sounds themselves when vibrating, and the reflected or emitted sound contributes to the build-up of resonances which are not present when the bone-conduction vibrator (25) is mounted on a human head.;By designing the measurement apparatus (1) such that all exposed parts on the front (21) located outside a coupling surface (14) for connecting the bone-conduction vibrator (25) do not have planar surfaces perpendicular to the main oscillation axis (5) or that otherwise, such planar surfaces consist of an acoustic foam having an acoustic dampening effect on sound waves impinging thereon, it is achieved that reflection or emission of airborne sound by such planar surfaces is reduced or less pronounced, which reduces resonances, and therefore the influence of such resonances on the measurement results is also reduced.