| abstract |
A flow rate sensor and a flow meter comprising a flow rate detecting member (12), which comprises a substrate, and a laminate provided on a first surface of the substrate and formed of a film type heating element, a film type temperature sensing element and an insulating layer inserted therebetween; a conduit (4) for an object fluid which is formed so that the heat of the flow rate detecting member (12) is transferred to the object fluid to be absorbed therein, a temperature sensing operation influenced by the heat absorption of the object fluid being carried out in the film type temperature sensing element on the basis of the generation of heat by the film type heating element, a flow rate of the object fluid in the conduit (4) being detected on the basis of the results of this operation; and a fin plate (14) extending into the interior of the conduit (4) through a central portion of a circular cross section thereof and bonded to a second surface of the substrate of the flow rate detecting member (12) with a bonding agent (16), the size of the fin plate (14) in the direction of a conduit (8) being larger than the thickness L2 thereof, whereby the flow rate of the fluid flowing in the conduit (4) can be measured accurately even when the fluid is comparatively high in viscosity, the fluid flow rate is comparatively small, or the environmental temperature condition widely varies. |