Title:
LIQUID SURFACE DETECTOR
Document Type and Number:
Japanese Patent JPH02193021
Kind Code:
A
Abstract:
PURPOSE:To enable detection of a liquid surface without generating a signal chattering and a wrong signal by arranging a float, an energization contact and a signal output means. CONSTITUTION:A ring-shaped permanent magnet 11 is fastened on an inner circumference of a float 1 and as the float 1 floating on a liquid surface comes within a specified range, a magnetic field of the magnet 11 acts on a lead switch 2 to close it. A contact 42 is formed on the tip underside of a leg part 41 wound with a heating wire 3 while an electrode plate 5 is arranged below the tip of the leg part 41 and a contact 51 is formed thereon facing the contact 42. Then, the wire 3 rises in temperature gradually with continuous energization and the leg part 41 is deformed substantially downward. Moreover, as the temperature of the wire 3 reaches a specified value, the leg part 41 is deformed so much that the contact 42 thereof contacts the contact 51 of the electrode plate 5 to conduct. This enables accurate detection of a liquid surface without generating a signal chattering and a wrong signal.
Inventors:
ISHIKAWA YUTAKA
Application Number:
JP1209689A
Publication Date:
July 30, 1990
Filing Date:
January 20, 1989
Export Citation:
Assignee:
NIPPON DENSO CO
International Classes:
G01F23/30; (IPC1-7): G01F23/30
Attorney, Agent or Firm:
Motomu Itou
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