SENSOR AND DEVICE FOR DETECTING PRESENCE/ABSENCE OF LIQUID AND SENSOR AND DEVICE FOR DETECTING PRESENCE/ ABSENCE AND TEMPERATURE OF LIQUID

摘要

PROBLEM TO BE SOLVED: To provide an inexpensive small-sized sensor which can readily and accurately detect the presence/absence and temperature of a liquid and has a simple constitution. ;SOLUTION: In a sensor for detecting presence/absence and temperature of liquid, a liquid presence/absence detecting section 2 constituted by laminating a thin film heating element 2a and a thin film temperature-sensitive body 2B upon a first substrate with an insulating layer in between and a liquid temperature detecting section 4 constituted by forming a thin film temperature-sensitive resistor for detecting temperature on a second substrate are housed in a container having external surface sections which make heat transfer with a liquid to be detected and the first and second substrates are joined to the internal surface sections of the container corresponding to the external surface sections so that heat can be transferred between the internal surface sections and substrates. The serially connected temperature- sensitive body 2B and the temperature-sensitive resistor of the section 4 are connected in parallel with the heating element 2A. The sensor obtains a liquid presence/absence detecting output B by comparing an output A obtained by connecting a change-over switch 14 to a-side with a threshold by means of a comparator 16. The sensor detects the temperature of the liquid from another output A obtained by connecting the switch 14 to b-side.;COPYRIGHT: (C)1999,JPO