| 摘要 |
<p>PURPOSE:To enable high-sensitivity detection by forming the detecting element of a vortex detector by using a high polymer piezoelectric film. CONSTITUTION:A vortex generation body 2 is fixed in a flow pipe 1 on its diameter by heat clamping and so sectioned in the shape of an isosceles triangular columnar body which has its bottom surface on an upstream side and its vortex on a downstream side. A rectangular recessed part 21 is bored in the flank of the vortex generation body 2 and a piezoelectric detecting element 3 is embedded in the recessed part 21 almost in level with the flank of the vortex generation body 2. This element is constituted by sticking electrodes 32 made of metal foil on both top and reverse surfaces of the high polymer piezoelectric film 31, and lead wires are connected to the electrodes 32 to output a piezoelectric signal. Here, fluid which flows under constant fluid pressure generate Karman vortexes by passing by the vortex generation body 2 and varying pressure caused by the vortex generation generates a thickness- directional voltage difference as a signal proportional to the vortexes between the films 31 on both flanks of the vortex generation body 2, and this signal is outputted as a flow rate signal by a signal processing means.</p> |
