Liquid sensor

• Main Author: KATO NOBUHIRO
• Format: Patent
• Language: Chinese; English
• Published: 26.12.2012
• Subjects: INVESTIGATING OR ANALYSING MATERIALS BY DETERMINING THEIRCHEMICAL OR PHYSICAL PROPERTIES; MEASURING; PHYSICS; TESTING

The invention claims a liquid sensor capable of suitably out the electrode pair of electrostatic capacitance. Liquid sensor the electrode part of 100 can be respectively and the low frequency oscillation circuit and high frequency oscillation circuit is connected with. Low frequency oscillation circuit output amplitude is vin1 the frequency of the cost is low the low frequency signal. High frequency oscillation circuit output amplitude is vin2 of the frequency is high the high frequency signal. From the electrode part obtains the two output signals under the condition counting part used for an equal to or vin1 and r1 and r2 = z2 vout 1-1 and 2-1 vout vin2 and calculating the electrode part of the electrostatic capacitance c1. Lp1 coupled the first output signal amplitude of the second output vout2 the signal amplitude. R1 is electrode part and low frequency oscillation part between the resistance value of the r2 is electrode part of the high frequency oscillation part between the resistance value.