Title:
電界センサ
Document Type and Number:
Japanese Patent JP3741978
Kind Code:
B2
Abstract:
PROBLEM TO BE SOLVED: To dispense with maintenance work for periodically replacing an internal liquid by eliminating a structure such as projecting from a can body, and a complicated structure by the presence of the internal liquid. SOLUTION: This electric field sensor comprises two chlorine ion solid membrane electrodes 31 and 32 arranged at a specific distance in the can body, a differential amplifier 4 for amplifying and outputting interelectrode voltage generated between the chlorine ion solid membrane electrodes 31 and 32 as a received signal, a timing delaying circuit 5 for outputting a contact point signal 53 for externally outputting a signal outputted by the differential amplifier 4 after passing convergence time of preset drift voltage by counting time when two contact points exposed to seawater are short-circuited by the seawater, a switch 6 operating so as to externally output the signal outputted by the differential amplifier 4 by receiving the contact point signal 53, and a detector 8 for outputting a signal when the signal sent out of the switch 6 becomes a prescribed threshold value or more.
Inventors:
Hiroyuki Morioka
Kazuhisa Kobayashi
Kazuhisa Kobayashi
Application Number:
JP2001218469A
Publication Date:
February 01, 2006
Filing Date:
July 18, 2001
Export Citation:
Assignee:
NEC
NEC Network and Sensor Systems Co., Ltd.
NEC Network and Sensor Systems Co., Ltd.
International Classes:
B63B49/00
Domestic Patent References:
| JP2000304533A | ||||
| JP2001228257A |
Attorney, Agent or Firm:
Masahiko Desk
Masashi Kudo
Yasuhisa Tanizawa
Masashi Kudo
Yasuhisa Tanizawa
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