Improved wind load pressure sensor

Abstract

The invention discloses an improved wind load pressure sensor, comprising a sensor shell, an oil charge sensitive body and a signal conditioning circuit, wherein, the oil charge sensitive body is composed of a sensitivity body shell in the form of a groove, a silicon integrated sensitive chip and an elastic separation film fixed on the opening of the groove, the ring circumambience of the back pressure face of the silicon integrated sensitive chip is fixed at the bottom of the groove through a fixed supporting ring in a sealing manner, the back pressure face of the silicon integrated sensitive chip is communicated with ambient pressure through a back pressure airway tube, the pressure surface of the silicon integrated sensitive chip is provided with a Wheatstone bridge on which a strain resistor is led to the signal conditioning circuit through an internal lead and a lead column and then is output, the non-pressure surface of the silicon integrated sensitive chip is provided with a temperature sensor, a heating resistor and a constant temperature control circuit controlling the heating resistor according to the temperature sensor, and silicon oil is filled among the elastic separation film, a groove internal ring surface and the pressure surface of the silicon integrated sensitive chip. The invention can control the temperature of the oil charge sensitive body, and eliminate the problem that an oil charge micro-pressure sensor is in fault due to the influence of ambient temperature, thereby realizing high-accuracy survey of wind loads.

Description

technical field [0001] The invention relates to an improved wind load pressure sensor based on the silicon piezoresistive sensitive principle and built with an oil-filled sensitive body. It is a thin micro pressure sensor used for wind load measurement on the surface of buildings and is mainly used in the field of civil engineering. Anti-typhoon and other harsh environment ability tests and early warning and protection systems for buildings. Background technique [0002] Wind load is one of the loads that must be considered in the design of building structures. With the development of urbanization, there are more and more high-rise buildings, and there are more and more studies on building wind loads. Currently, there are three main methods used to measure the impact of wind loads on buildings. (1) Wind pressure measurement: Use a pressure sensor to directly measure the wind pressure distribution of a building or its model. This method can obtain the average pressure and ...

AI Technical Summary

Problems solved by technology

However, the technology is complex and expensive, and when the internal structural parameters of the building change, the model must be redesigned and tested again.

(3) High-frequency dynamic balance test: This is a new technology developed in the past 20 years. It uses a high-frequency, high-sensitivity high-frequency dynamic balance to directly measure the static and dynamic generalized loads of the rigid model, and then according to the structural parameters , to obtain the dynamic response of the building through computational processing, but the problem is that it is expensive

However, it has two outstanding difficulties in the application of wind load measurement: one is that the elastic diaphragm of the silicon chip must be very thin because the wind load is a measurement of tiny pressure, so that it is not resistant to wind and rain and is easily damaged. Second, the pressure-sensitive area of ​​the silicon integrated sensitive chip is too small, and the measurement of a single point is easy to produce a large error with the average value.

Although the oil-filled structure can overcome these problems, it is followed by the error caused by the oil-filled silicon integrated sensitive chip due to the thermal expansion and contraction of the oil with the external environment, which is intolerable for small pressures. The mass-produced oil-filled cores are generally above 40kPa, and when the volume is low (such as below 5kPa), the temperature error after oil-filling cannot be overcome for many years.

Therefore, silicon piezoresistive pressure sensors are often not used in the industry

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