摘要:
A thickness extensional piezoelectric resonator includes a substantially rectangular piezoelectric strip, first and second excitation electrodes disposed on both surfaces of the piezoelectric strip, and an internal electrode disposed inside the piezoelectric strip. The first and second excitation electrodes are located on opposite sides of the piezoelectric strip. The internal electrode is located opposite to the first and second excitation electrodes. Assuming that the piezoelectric plate has a width W and a thickness t, the piezoelectric plate is constructed such that W/d is less than about 6.1 if d=t/n.
摘要翻译:厚度延伸压电谐振器包括基本上矩形的压电条,设置在压电条的两个表面上的第一和第二激励电极以及设置在压电条内的内部电极。 第一和第二激励电极位于压电条的相对侧上。 内部电极与第一和第二激励电极相对。 假设压电板具有宽度W和厚度t,则如果d = t / n,则压电板被构造成使得W / d小于约6.1。
摘要:
A thickness extensional piezoelectric resonator utilizes harmonics of a thickness extensional vibration mode and has a significantly reduced size and significantly increased capacitance while not being susceptible to the effects of the stray capacitance of a circuit board upon which the resonator is mounted. The resonator includes a piezoelectric strip, first and second excitation electrodes located on one of two respective major surfaces of the piezoelectric strip, and internal electrodes disposed inside the piezoelectric strip. The first and second excitation electrodes are located on opposite sides of the piezoelectric strip. The internal electrodes are located opposite to the first and second excitation electrodes to thereby define a vibrating portion. Vibration-attenuating portions are located on opposite sides of the vibrating portion only along the longitudinal direction of the piezoelectric strip. No vibration-attenuating portions are located in the lateral direction of the piezoelectric strip.
摘要:
An energy-trap thickness extensional vibration mode piezoelectric resonator uses a harmonic of a thickness extensional vibration mode and effectively suppresses generation of unwanted spurious vibrations. The energy-trap thickness extensional vibration mode piezoelectric resonator includes a piezoelectric strip, first and second excitation electrodes located on opposite surfaces of the piezoelectric strip, and an internal electrode disposed inside the piezoelectric strip. The first and second excitation electrodes are located on opposite ends of the piezoelectric strip in an overlapping arrangement. The internal electrode is located opposite to the first and second excitation electrodes. The first and second excitation electrodes overlap each other over a length of l such that l/d is not greater than about 6, where d=t/n.
摘要:
An energy-trapping piezoelectric resonator vibrates in a third-order wave of a thickness-extension vibration mode. The piezoelectric resonator includes a piezoelectric substrate polarized along its thickness. A ratio of the width W to the thickness T of the substrate is determined to be about 0.88.+-.5%, 1.06.+-.4%, 1.32.+-.5%, 1.80.+-.3%, 2.30.+-.3%, 2.69.+-.3%, 3.16.+-.2%, or 3.64.+-.2%. First and second electrodes are respectively disposed on the obverse and reverse surfaces of the substrate to cover the entire width and opposedly face each other at the central portion of the substrate in the longitudinal direction so as to form a resonance portion between the first and second electrodes. It is thus possible to obtain a piezoelectric resonator which does not require a large extra area of the substrate around the resonance portion and which exhibits good resonance characteristics by effectively suppressing unwanted spurious responses in a range between and near the resonant frequency and the anti-resonant frequency.
摘要:
A composite vibration device includes a piezoelectric element defining a vibrating member, which is made of a material having a first acoustical impedance, first and second reflecting layers are connected to respective end surfaces of the piezoelectric element, each of the layers are made of a material having a second acoustical impedance lower than the first acoustical impedance, and first and second supporting members. Each of the first and second supporting members is made of a material having an acoustical impedance higher than the second acoustical impedance and is connected to the outer surface of each of the first and second reflecting layers. Vibrations propagated from the piezoelectric element are reflected at the interfaces between the reflecting layers and the supporting members.
摘要:
Disclosed herein is a vibrating unit containing a vibrator for utilizing vibration of the vibrator. A vibration transfer part is coupled to a portion of the vibrator exhibiting the minimum displacement or a portion close thereto, and a resonant part is coupled to the vibration transfer part and formed to receive vibration propagated from the vibrator to the vibration transfer part to resonate. The vibrating unit utilizes a dynamic vibration absorbing phenomenon.
摘要:
A composite-material vibrating device includes a vibrating member, at least three reflective layers, and holding members. The vibrating member is made of material having a first acoustic impedance Z1 and that functions as a vibration generating source. The at least three reflective layers are made of material having a second acoustic impedance Z2 that is smaller than the first acoustic impedance Z1, and are coupled to respective outer surfaces located along three directions of the vibrating member. The holding members are made of a material having a third acoustic impedance Z3 that is greater than the second acoustic impedance Z2 and that are coupled to surfaces opposite to the surfaces, coupled to the vibrating member, of the reflective layers. Vibrations that have propagated from the vibrating member to the reflective layers are reflected at interfaces between the reflective layers and the corresponding holding members.
摘要:
Disclosed herein is a vibrating unit comprising vibration cancel means which is coupled to a vibration source through a vibration transfer part. The vibration cancel means receives vibration from the vibration source and resonates in a bending mode, to cancel vibration as propagated by a dynamic vibration absorbing phenomenon.
摘要:
A multi-mode piezoelectric filter includes a piezoelectric substrate made of a LiTaO.sub.3 single crystal, a plurality of spaced electrodes which are formed adjacently on a front major surface of the substrate, and a counter electrode which is formed on a rear major surface of the substrate in opposition to the spaced electrodes. The spaced electrodes and the counter electrode coact with the intervening portion of the substrate to form two or more energy trapped type multi-mode filter elements vibrating in the thickness shear mode such that the filter elements are coupled to form a cascade connection. Damping material such as silicone gel is applied at least on the filter elements.
摘要:
Disclosed herein is an energy trap type piezo-resonator (11) utilizing a thickness shear vibration mode, which is prepared by forming electrodes (13, 14) on both major surfaces of a piezoelectric substrate (12) and providing dynamic damper parts (17, 18) being held between grooves (15a, 15b; 16a, 16b) for preventing leakage of vibration from a vibrating part opposing the electrodes (13, 14) to each other to end portions of the piezoelectric substrate.