Mounting for plural piezoelectric vibrator units

Claim 1

In a piezoelectric vibrator unit having (i) a pair of vibrator assemblies each consisting of a holder case, a vibrator plate having excitation electrode means formed on the principal faces thereof, and lead wires for said excitation electrodes, and (ii) a metal plate for preventing mutual interference between the vibrator plates in said vibrator assemblies, the improvement which comprises, in combination: (a) said holder case is of an electrically insulating material and has a front side provided with a recess for receiving therein said vibrator plate, (b) said lead wires extend through and are secured in a side wall of said case bounding said recess and have tip portions located in alignment with one another within said recess so that said tip portions can serve for the spacing of said vibrator plate from a bottom wall of said case bounding said recess, (c) said vibrator plate is fixed within said recess by said tip portions being bonded to said excitation electrode means, (d) said bottom wall includes port means therethrough to permit the micro-adjustment of said excitation electrode means facing said bottom wall, (e) said front side of one of said holder cases of said pair of vibrator assemblies faces in a direction opposite to the direction faced by said front side of the other of said holder cases of said pair of vibrator assemblies, (f) said respective front sides of said holder cases are covered by said metal plate and are attached thereto at the respective sides of said metal plate, said pair of vibrator assemblies being coupled fixedly to each other together through the medium of said metal plate, and thereby providing port means for the microadjustment of vibration frequencies of both vibrator plates at the outer faces of said piezoelectric vibrator unit.