| 摘要 |
A sensor providing an output indicating pressure includes means, e.g. a coil 58 to excite a vibrating beam 35, 42 at its natural frequency, and means 23, 24, 27, 30, 37 to load the beam 35, 42 in response to pressure sensed by bellows 15, 16 to alter the natural frequency of the beam 35, 42. The frequency output is sensed by a capacitor pick off mounted on the same side of the beam 35, 42 as the coil 58 to excite the beam. Changes in the output frequency provide an indication of the pressure being measured. Interaction a between the drive and pick-up is minimised by the use of a coil drive and capacitive sensing whilst providing the drive and sensing on the same side of the beam simplifies the construction and adjustment. <IMAGE> |
