Piezoelectric bimorph switch

摘要

The present invention relates to a piezoelectric bimorph switch, specifically a cantilever (single clamped beam) switch, which can be actively opened and closed. Piezoelectric bimorph switch are known from the prior art. Such a switch may be regarded as an actuator. Actuators are regarded as a subdivision of transducers. They are devices, which transform an input signal (mainly an electrical signal) into motion. Electrical motors, pneumatic actuators, hydraulic pistons, relays, comb drive, piezoelectric actuators, thermal bimorphs, Digital Micromirror Devices and electroactive polymers are some examples of such actuators. The switch of the invention comprises piezoelectric stack layers (121, 122), which form a symmetrical stack, wherein an electric field is always applied in the same direction as the poling direction of the piezoelectric layers.

主权项

1. Device comprising:
a microelectromechanical system (MEMS), a piezoelectric bimorph switch for operating the MEMS, the piezoelectric bimorph switch including a plurality of piezoelectric layers, which include a first piezoelectric layer having a first poling direction and a second piezoelectric layer having a second poling direction that is different from the first poling direction, the plurality of piezoelectric layers forming a symmetrical stack, and one or more electrical switches configured and arranged to:
open the piezoelectric bimorph switch by applying a first electric field, having a direction that is the same as the first poling direction, to the first piezoelectric layer, andclose the piezoelectric bimorph switch by applying a second electric field, having a direction that is the same as the second poling direction, to the second piezoelectric layer.