An MEMS inertial switch based on three-section long inclined beam bistable structure

Abstract

The invention discloses an MEMS inertial switch based on a three-section long inclined beam bistable structure. The switch comprises: a switch housing, a bistable mechanism and a switch auxiliary mechanism. The switch auxiliary mechanism and the bistable mechanism are sequentially arranged inside the switch housing in the acceleration direction, the switch auxiliary mechanism includes a spring body and a first mass, the bistable mechanism comprises a three-section long inclined beam structure and a second mass, a switch contact is provided in the switch housing at a position opposite the second mass block, the first mass is disposed opposite the second mass, the mass of the first mass is larger than the mass of the second mass. When the MEMS inertial switch is subjected to the set acceleration, the first mass collides with the second mass under the action of the inertia, so that the second mass moves in the acceleration direction. The bistable mechanism presses the switch contact fromone steady state to the other steady state, and turns on the circuit. The MEMS inertial switch provided by the invention has the advantages of high sensitivity, strong electromagnetic interference resistance and strong mechanical vibration resistance.

Description

technical field [0001] The invention relates to the field of microelectromechanical systems, in particular to a MEMS inertial switch based on a three-section long inclined beam bistable structure. Background technique [0002] Micro-Electro-Mechanical Systems (MEMS) refers to high-tech mechanical and electronic devices with a size of a few millimeters or less. Its internal structure is generally on the order of microns or even nanometers. The size of common MEMS products is generally on the order of millimeters, or even hundreds of microns. . MEMS is mainly composed of three parts: sensors, actuators (actuators) and micro energy sources. The MEMS acceleration switch is a MEMS device that integrates micro sensors and actuators, and can complete the on-off (On-Off) function of the switch under the excitation of environmental acceleration. At present, the common MEMS inertial sensing and actuator devices are mainly accelerometers, whose structure is composed of sensing mass, ...

AI Technical Summary

Problems solved by technology

At present, the common MEMS inertial sensing and actuator devices are mainly accelerometers, whose structure is composed of sensing mass, support beam system and control feedback circuit. The structure is very complex and difficult to process.

The control feedback circuit needs to work under the condition of power on, and it is prone to malfunction under strong electromagnetic interference, so it is not suitable for anti-electromagnetic interference equipment

In addition, there are some micro-acceleration switches with purely mechanical structures, but these switches do not have a locking function after they are closed, so the ability to resist external environmental interference such as mechanical vibration is insufficient

Images