Thermal bubble type minitype inertia sensing element

Abstract

The invention provides a hot bubble micro inertial sensing cell, a micro device formed by micro-manufacturing technique, setting a heater on a basal plate and four groups of temperature sensing cells around the heater symmetrically, to sense the temperature change, setting a sealed cover on the basal plate, which is sealed to coat the heater and temperature sensors to make a liquid phase filled in a space formed by the sealed cover and basal plate; using the heater to heat the liquid phase fluid to form a hot bubble in the liquid phase fluid, controlling the size of bubble by water surface tension and temperature control to make the temperature sensing cells able to sense the change of temperature distribution, the inclined direction and magnitude as an incline meter, and the direction and magnitude of acceleration as an acceleration gauge.

Description

technical field [0001] The present invention relates to a miniature inertial sensing unit, in particular to a hot-bubble miniature inertial sensing unit used as an inclinometer and an accelerometer to sense changes in position, inclination angle and acceleration. Background technique [0002] Existing inertial sensing elements, such as accelerometers and gyroscopes, are indispensable components for navigation control. However, due to their bulky size and high price, they are not suitable for promotion. Micro-electromechanical technology is a kind of micro-machining technology (Micromachining Technology) that has emerged in recent years. It uses this technology to make miniature inertial sensing elements, especially micro-accelerometers. Its characteristics can be better than those produced by traditional processing technology. , Higher sensitivity, the sensed microgravity acceleration can reach the μg level, and the micro accelerometer has the advantages of light, thin and s...

AI Technical Summary

Problems solved by technology

However, the biggest disadvantage of this structure is that the elastic mass block is easily damaged by sudden external impact.

[0004] For this reason, then develop a kind of gas thermal convection type accelerometer, to overcome the above-mentioned shortcoming, it is to utilize the natural principle of gas thermal convection to replace the mobile effect of above-mentioned mass block, as U.S. Patent No. US2445394, US2554512, US3241374 and US5581034, Please refer to U.S. Patents US5719333 and US6171880 for those who form gas heat convection accelerometers by micromachining technology; although this method can overcome the problem that the mass block is easily damaged, however, due to the slow heat transfer characteristics of the gas, this kind of The response speed of the gas thermal convection accelerometer is quite slow (~30Hz), which limits its application. At the same time, because its packaging method needs to be completely airtight to control the ambient pressure value, it also increases the cost of implementation.

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