| 摘要 |
PURPOSE:To reduce cost by disposing a moisture sensitive part so as to enclose the same in an air permeable state and providing a frame body to hold the moisture sensitive part via a means for supporting the same without restraining the displacement of a base plate which expands or contracts with a humidity change. CONSTITUTION:The base plate 11 of the moisture sensitive part 10 is made of a material which expands or contracts with the humidy change. The base plate has a slender shape and a strain gage element 12 is formed on the surface thereof by means such as adhesion in the longitudinal direction thereof. The element 12 is made of an alloy such as Cu-Ni and is formed to a wire or foil shape. The resistance value of the element 12 changes with the rate of the expansion or contraction. A protective film 13 to cover such element 12 is provided atop the base plate 11. The film 13 is made of a thin film of the material quality similar to the material quality of the plate 11. The element 12 of such moisture sensitive part 10 expands or contracts according to the expansion or contraction of the base plate 11 when said plate expands or contracts with the humidity change. Then the resistance value thereof changes. The humidity is detected in accordance with the change of the resistance value. The detector is thus produced at a low cost.
|
