Improvement of structure of frequency-change-type three-axis acceleration sensor

In the frequency-change-type three-axis acceleration sensor developed so far, the frequency-change rate in the z-axis direction of its thickness direction was considerably smaller than the change rates in the x- and y-axis directions of its plane direction. As a method for increasing the small change rate, a sensory structure was proposed in which the mass was sandwiched between two right-angled vibrators. However, there was a problem that the structure became three-dimensional and complicated. Therefore, simplification of the structure has been considered desirable. Here, to simplify the structure and increase the sensitivity, an improved new frequency-change-type three-axis acceleration sensor is proposed in which all of the vibrators are arranged only on the upper surface of the mass. The sensor characteristics were analyzed by the finite element method, and verified experimentally. (C) 2020 The Japan Society of Applied Physics.