Dynamic calibration assembly for pressure sensor - has coil assembly to drive piston for compressing liquid at variable force in calibration chamber

摘要

An exciter assembly (1) rests on flexible mounts (3) on a support (2). The fixed part of the exciter comprises a foot (4) containing an excitation winding (5) and is extended by a support housing (6) whose upper part forms a cylindrical cavity (7) closed by a cover (8). The foot has a cylindrical opening (9) which houses a moving coil (10) fixed to a piston (11) which displaces in the cavity (7) closed by a cover (8). The foot has a cylindrical opening (9) which houses a moving coil (10) fixed to a piston (11) which displaces in the cavity to define a calibration chamber (12). The moving coil and piston rest on rubber support (13) filled with compressed air and fastened by studs (14) through a retaining plate (15). The sensor being calibrated (16) is placed on a side wall of the calibration chamber which is filled with liquid (17). The coil assemblies displace the piston and apply a sinusoidal pressure to the fluid. The piston displacement is measured by an accelerometer and from the initial static pressure the pressure in the chamber can be calculated. The device is used for calibrating pressure transducers.