Abstract: A piezoelectric electroacoustic transducer, including a plurality of piezoelectric layers deposited to define a deposited product, flexurally vibrates the deposited product by polarizing the entire piezoelectric ceramic layers in the same thickness direction and also by applying an alternating signal between external electrodes disposed on the front/rear major surfaces of the deposited product and an internal electrode disposed between the ceramic layers. A dummy electrode is provided between the ceramic layers outside the internal electrode via a gap, and a portion of the internal electrode is exposed at at least one side surface of the piezoelectric ceramic layers, while the dummy electrode is exposed at the other side surface of the piezoelectric ceramic layers. The external electrodes extend to the side surfaces other than the side surface at which the internal electrode is exposed.

Abstract: A piezoelectric electroacoustic transducer that is capable of preventing a short-circuit between an internal electrode and external electrode and also capable of preventing cracks of ceramic layers during polarization to improve a yielding rate. A piezoelectric electroacoustic transducer, including a plurality of piezoelectric layers deposited to define a deposited product, flexually vibrates the deposited product by polarizing the entire piezoelectric ceramic layers in the same thickness direction and also by applying an alternating signal between external electrodes disposed on the front/rear major surfaces of the deposited product and an internal electrode disposed between the ceramic layers. A dummy electrode is provided between the ceramic layers outside the internal electrode via a gap, and a portion of the internal electrode is exposed at at least one side surface of the piezoelectric ceramic layers, while the dummy electrode is exposed at the other side surface of the piezoelectric ceramic layers.

Abstract: A frequency control apparatus including a shielding board that is provided with a window for exposing some or all of a plurality of electrodes disposed on a piezoelectric substrate, and a shutter for opening and closing the window. An aperture pattern board is provided between the shielding board and a piezoelectric resonator. On the aperture pattern board, combinations of apertures are provided which correspond to the A electrodes exposed through the window on the shielding board at one time. After measuring the frequencies for respective elements and measuring the variations from the target frequency, the suitable pattern of apertures is selected from the aperture pattern board according to the amount of variations, and then the frequency control is carried out only on the elements selected through the apertures.

Abstract: A piezoelectric resonator includes a base member in which piezoelectric layers and internal electrodes are laminated. At one side surface of the base member, the internal electrodes are alternately covered with a first insulating film and with a second film, and first and second external electrodes are disposed thereon alternately connecting the internal electrodes to the first and second external electrodes. An additional material is disposed on the side surface of the base member opposite from the side surface on which the external electrodes are formed by applying ink via an ink jet printer or the like. The additional material is disposed at the opposite ends of the base member in the longitudinal direction. A metal film may also be disposed at a central portion of the base member by a thick film forming method.

Abstract: A piezoelectric resonator having a small spurious resonance and a large difference .increment.F between the resonant frequency and the antiresonant frequency is constructed that a resonant frequency or antiresonant frequency can be easily and accurately adjusted to a low frequency. The piezoelectric resonator has a base member which includes a plurality of laminated piezoelectric layers and a plurality of inner electrodes disposed substantially perpendicularly to the longitudinal direction of the base member. The plurality of piezoelectric layers are polarized in the longitudinal direction of the base member. A first external electrode and a second external electrode are located on a surface of the base member and connected to the plurality of electrodes. The resonant frequency of the piezoelectric resonator is adjusted by cutting an intermediate portion in the longitudinal direction of the base member.

Abstract: A laminator carrier, which holds superposed sheet members, is subjected to heat and pressure while being transported. The laminator carrier includes a carrier base on which the superposed sheet members are placed, a cover sheet which is disposed on the carrier base so as to cover the sheet members placed on the carrier base, a holding mechanism for holding the cover sheet such that the cover sheet is movable with respect to the carrier base in a transport direction of the laminator carrier. Accordingly, movement of the cover sheet during application of heat and pressure is absorbed by the holding member.