Several important class of pressure sensors
Sapphire pressure sensor
Sapphire pressuresensorworking principle of strain resistance, the use of silicon - the semiconductor sensor as sapphire, with a unique measurement characteristics.
By the single crystal sapphire insulator elements, lag does not occur, fatigue and creep; sapphire to be stronger than silicon, hardness higher, not afraid of deformation; and sapphire has a very good flexibility and insulation, therefore, the use of silicon - Sapphire Manufacturing semiconductor sensitive element is not sensitive to temperature change, even under high temperature conditions, also has good working properties; sapphire strong anti-radiation properties; In addition, silicon - the semiconductor sensor sapphire noP-Ndrift, therefore, fundamentally simplifies the manufacturing process, improve repeatability and ensure a high yield.
Silicon - the semiconductor sensing element manufactured sapphire pressure sensor and transmitter can be in the most adverse working conditions, work, and high reliability, good accuracy, the temperature error is extremely small, cost-effective.
Silicon Pressure Sensors
Diffused silicon pressuresensor's working principle is: the pressure measured media directly on the sensor diaphragm (stainless steelor ceramic), medium pressure diaphragm is proportional to the generation and micro-displacement, the sensor's resistance changes, the electronic line detection of this change and convert the output of a standard corresponding to the pressuremeasurementsignal.
Ceramic Pressure sensor
Corrosion-resistant ceramic pressure sensor is not the transmission fluid pressure directly on the front surface of the ceramic diaphragm, the surface of the diaphragm chamber, so that the deformation of the diaphragm produce small, thick film resistors printed on the back of the ceramic diaphragm, connected to a Wheatstone bridge (closed bridge), due to the piezoresistive effect varistor so that the bridge is proportional to the pressure to produce a highly linear, with the excitation voltage is proportional to the voltage signal, the standard signal according to the different calibration of the pressure range for the2.0,3.0,3.3MV, etc. and the strain sensor can be compatible. By laser calibration, the sensor has high temperature stability and time stability, temperature compensation sensor built0℃ ~70℃, and can and most direct contact with the media.
Ceramic is a recognized high elasticity, corrosion resistance, abrasion resistance, shock and vibration material. Ceramic thick film thermal stability and its resistance can make it up to operating temperature range -40℃ ~135℃, and has measured high precision and high stability. Electrical insulation greater than2KV, the output signal strength, long-term stability. High properties, low price of the ceramic sensor pressure sensor will be the development direction of a comprehensive alternative to the United States and Europe the trend of other types of sensors, more and more users in China, the use of ceramic sensors instead diffused silicon pressure sensor.
Ceramic thick film structure and force-sensitiveZ- complementary elements
Following the proliferation of thick-film pressure sensor is a silicon pressure sensor pressure sensor after another major technological innovation, and force-sensitiveZ- element is the only digital signal output at home and abroad of sensitivecomponents, the ceramic thick film technology and force-sensitiveZ- Components of the most ingenious combination of a simple circuit can rise to a performance, a new type of low cost sensors. Specifically, the ceramic thick film technology has the following advantages:
Excellent elastic properties of ceramic, smooth, uniform, dense material in the level of quality within the Hooke's law are strictly followed, no plastic deformation.
Thick film resistors (including high temperature wire) flexible diaphragm with ceramic sintered together firmly, without using glue to paste. The rigid structure of small creep, drift, static, stable performance, good dynamic performance.
Thick elastic structure is simple and easy preparation. It diffused silicon pressure sensors, semiconductor planar process without diffusion resistance to form a flexible diaphragm, substantially reduces the initial investment and production cost of processing.
Resistance of ceramic thick film of liquid or gaseous media corrosion, do not pass through the conversion of stainless steel diaphragm and silicone oil and isolation, package structure is simplified, and further reduce costs.
Wide range of work. Range depends on the thickness of the diaphragm and the ratio of effective radius, as long as the micro-pressure not less than1KPa, in principle, the higher range is also easy to implement.
Wide operating temperature range, up to -40℃ ~120℃.
Number of ceramic thick film force sensor design
Number of ceramic thick film force sensors mainly by the ceramic ring, ceramic diaphragm and ceramic cover of three parts. Ceramic diaphragm elastomer as a sense of power, with95% of theAL2O3porcelain finish from, requiring smooth, uniform, mass density, its thickness and effective radius as the design range may be.
Ceramic ring burned by hot die casting molding temperature. Between the diaphragm and the ceramic ring ceramic high-temperature glass paste, by thick film printing, thermal burn technology to burn together to form the sense of power clamped elastomer cup, that is clamped in the ceramic part to be formed No creep rigid structure. On the surface of the ceramic diaphragm, the bottom of the cups, made with thick film technology sensor circuit. Ceramic cover to cover the lower part of the circular groove with a certain gap between the diaphragm, the diaphragm by the limit prevents overload due to excessive bending and rupture, the formation of anti-overload protection sensor.