Nheyo yekushanda uye kuumbwa kwe capacitive pressure sensor

Sensor yekumanikidza ine capacitive inoumbwa nezvidimbu zviviri zvinofamba (elastic metal diaphragm), zvidimbu zviviri zvakagadzika (simbi inoputira pagirazi rakakombama pa diaphragm yepamusoro nepazasi), materminal ekubuda uye housing, nezvimwewo. Ma capacitor maviri akatevedzana anoumbwa pakati peplate inofamba nemaplate maviri akagadzika. Kana kumanikidzwa kwekupinda kuchishanda pa diaphragm ye elastic, diaphragm ye elastic inogadzira displacement, iyo inosungirwa kuderedza daro nechidimbu chimwe chakagadzika, uye kuwedzera daro nechidimbu chimwe chakagadzika (chinogona kuratidzwa nepepa). Daro riri pakati pemaelectrode maviri esimbi ndechimwe chezvinhu zvakakosha zvinokanganisa capacitance, daro rinowedzera, capacitance inoderera, daro rinoderera, capacitance inowedzera. Rudzi urwu rwechimiro runonzi differential structure umo ma parameter ezvinhu zviviri zvinonzwa anochinjwa nehuwandu hwakafanana asi hwakapesana nekuda kwehuwandu hwakayerwa.

Kana diaphragm ye elastic yakaiswa pakati pekumanikidzwa kwepadivi nekumanikidzwa kwemhepo (nzvimbo yepamusoro ye diaphragm ye elastic iri mumhepo), kumanikidzwa kwakayerwa ndiyo tafura; Kana diaphragm ye elastic yakaiswa pakati pekumanikidzwa kwepadivi nekumanikidzwa kwe vacuum (nzvimbo yepamusoro ye diaphragm ye elastic inopfuura nemu vacuum), kumanikidzwa kwakakwana kunoyerwa. Kugona kwe capacitor kwakaenzana ne dielectric nenzvimbo yayo inoshanda pakati pemaplate maviri e capacitor, uye kwakaenzana nekureba pakati pemaplate maviri, kureva, C=ε A/ D, uko ε iri dielectric constant ye dielectric, A inzvimbo inoshanda pakati pemaelectrode maviri esimbi, D ndiyo daro riri pakati pemaelectrode maviri esimbi. Kubva pahukama uhwu, zvinogona kuonekwa kuti kana maviri ema parameter asina kuchinja uye imwe parameter ikashandiswa se variable, capacitance ichachinja ne parameter inochinja.
Kune mhando dzakawanda dzemasekete ekuyera anoshandiswa ne capacitive pressure sensor. Ngatitorei bridge circuit semuenzaniso kuti tiratidze mashandiro e capacitance differential sensor measuring circuit. Nekuti capacitance iAC parameter, bhiriji rinofashukira neAC kuburikidza ne transformer. Transformer ine coil mbiri uye capacitance ye bhiriji, kana pasina inlet pressure, bhiriji riri mu balance, uye capacitance values ​​mbiri dzakaenzana ne C0, kana pressure effect, imwe ye capacitance value ye C0 + delta C, imwe capacitance value ye C0 - delta, C (delta C ye external pressure inokonzerwa nekusiyana kwe capacitance), bhiriji riri kunze kwe balance, Apo capacitance value yakakwira, voltage yakakwirawo, uye musiyano we voltage unogadzirwa pakati pe capacitors mbiri, kubva ipapo bhiriji rinogadzira voltage output U inomiririra intake pressure.