| 摘要 |
PURPOSE:To ensure the resistance to the external impact due to the mechanical vibration and at the same time to improve the humidity resistance, by holding a spacer between the layers of a multielement filter formed by stacking several units of edge mode ceramic filter in the direction of thickness and then storing the filter into a packing case. CONSTITUTION:Four units of the element in which lead terminals 2'', 3'' and 4'' are connected to an input terminal 2', an earth terminal 3' and output terminal 4' respectively are held by a holder 9 and then stacked to each other in the direction of thickness so that four units of piezoelectric ceramic plate 1 are distributed almost equidistantly at the positions of >= about 1.5 times as much as the width of the plate 1 from the edge part of each element containing driving electrodes 2, 3 and 4. In addition, a spacer 8 made of a flexible material having a thickness a little less than the space between the layers is held between the area from the layer held by the holder 9 to the edge where an electrode concerned in the vibration of each plate 1. The plates 1 are then fixed with the holder 9 to be stored into a packing case 7. Then the area between the case 7 and each of terminals 2'', 3'' and 4'' is sealed up and fixed with the insulating resin. |
