Nihon Dempa Kogyo Co., Ltd.

Shingo Kawanishi

Kozo Ono

Minoru Ishihara

Ryoichi Ichikawa

Hiroki Iwai

Masahiro Yoshimatsu

Yu Iwai

Yuichi Kawase

Toshiaki Motegi

Shunsuke Ueno

A piezoelectric device including a tuning-fork piezoelectric vibrating element having a base and a pair of vibrating arms positioned parallel to each other and extending from the base at right angles. The piezoelectric device further including a pair of support arms extending from the base positioned parallel to each other and in the same direction as the vibrating arms. A package is included having a lid and a housing recess sealed by the lid wherein the tuning-fork piezoelectric vibrating element is housed. A pair of supports are provided on a bottom face of the housing recess for fixing the tuning-fork piezoelectric vibrating element by the support arms. A clearance groove is formed in the bottom face of the housing access to prevent the tuning-fork piezoelectric vibrating element from colliding against the bottom face of the housing recess.

Tuning fork piezoelectric vibrator with clearance groove formed on the base side of the package

Tuning-fork type quartz-crystal vibrating pieces are disclosed, of which the vibration frequency can be adjusted without increasing CI. An exemplary piezoelectric device has a pair of vibrating arms extending in a predetermined direction from a first edge of a base. Respective first grooves are defined in a first principal surface of the vibrating arms. The first grooves extend in the predetermined direction, and have first excitation electrodes extending from a back-edge surface but not completely to a front-edge surface of the grooves. Respective second grooves are defined in a second principal surface, opposite the first principal surface, of the vibrating arms. The second grooves extend in the predetermined direction, and have second excitation electrodes extending from a back-edge surface completely to a front-edge surface of the second grooves.

Tuning-fork type quartz-crystal vibrating pieces and piezoelectric devices having low crystal impedance

The piezoelectric device comprises a piezoelectric vibrating piece having a base portion, a pair of vibrating arms extending in a specified direction from the base portion, and a pair of connection portions disposed on the pair of the supporting arms; a package having a bottom surface which accommodates the piezoelectric vibrating piece and side faces surrounding the bottom surface, in which a pair of electrode pads corresponding to the connection portions are formed on the bottom surface; and adhesive for bonding the pair of the electrode pads with the pair of connection portions. One electrode pad and the other electrode pad, with adhesive applied to the electrode pads, are shifted with respect to each other in a predetermined direction.

Piezoelectric device with asymmetrically mounted tuning-fork type piezoelectric vibrating piece

An exemplary tuning-fork type quartz-crystal vibrating piece includes a base, a pair of vibrating arms, and a connecting electrode electrically connectable to an internal conductive member of a package. The base and vibrating arms are made of a piezoelectric material. The vibrating arms extend in a prescribed direction from the base and have at least one excitation electrode that is electrically connected to the connecting electrode. Each vibrating arm has an upper and a lower axis main surface each defining a respective groove extending in the prescribed direction. Each vibrating arm also has axis edge-side surfaces extending between the first and second axis main surfaces. The excitation electrode includes a surface electrode located inside the grooves on the axis main surfaces of at least one vibrating arm and a side electrode located on the axis edge-side surfaces of the at least one vibrating arm. The surface connecting electrode.

Tuning-fork type piezoelectric vibrating pieces and devices exhibiting reduced hampering of vibration

Piezoelectric vibrating pieces are disclosed. An exemplary piece includes a base and at least a pair of vibrating arms connected to the base. The vibrating arms extend from one end of the base in a first direction. A vibrating root portion is situated between the vibrating arms. A pair of supporting arms extend, outboard of the vibrating arms, in the first direction from the one end of the base. Respective supporting root portions are situated between each vibrating arm and its outboard supporting arm, at the same position (denoted, e.g., K, K) in the first direction of the vibrating root portion.

Tuning-fork type piezoelectric vibrating pieces having similarly shaped vibrating-root and supporting root portions

Piezoelectric vibrating pieces are disclosed that include a base portion and first and second vibrating arms extending in a longitudinal direction from the base portion. Each vibrating arm has first and second main surfaces, a first groove on the first main surface, and a second groove on the second main surface. The grooves extend in the longitudinal. By adjusting the length and shapes of at least the first grooves relative to each other, the rigidity of the vibrating arms can be balanced and adverse effects of deformed regions between the vibrating arms caused by anomalous etching can be reduced.

Piezoelectric vibrating pieces, and piezoelectric vibrators and oscillators comprising same

Piezoelectric vibrating pieces are disclosed that have a base and a pair of vibrating arms extending from one end of the base in a designated direction. A respective groove is defined in each of the upper and lower surfaces of each vibrating arm. The grooves extend in the designated direction and have a first width. Each groove includes a respective rib feature having a second width that is narrower than the first width. A piezoelectric frame includes the piezoelectric device and an outer frame surrounding the device. A piezoelectric device includes the piezoelectric vibrating piece or piezoelectric frame, a lid, and a base.

Piezoelectric vibrating pieces, frames, and devices

The piezoelectric vibrating piece () comprises a base portion () having an adhesive area on a first surface of electrically conductive adhesivefor mounting, a pair of vibrating arms () extending in a first direction from one edge of the base portion, base electrodes () arranged in the base portion, an exciting electrode () extending in a first direction and connecting the base electrode to excite a pair of vibrating arms. The area where the base electrodes () conduct the electrically conductive adhesive () is smaller than the adhesive area ().

Piezoelectric vibrating pieces and piezoelectric devices

A tuning fork type piezoelectric vibrator is provided with vibrating arms which can improve shock resistance while suppressing a CI value to a small value. A first groove (base end side) and a second groove (tip side) extend along a longitudinal direction from a base end of the vibrating arm and are formed on at least one of a front surface or a back surface of the vibrating arms. Then, a ratio L/Lwhich is the ratio of a length Lof the first groove to a length Lfrom the base end of the vibrating arm to the tip of the second groove, is set between 0.35 and 0.65, and a ratio d/Lwhich is the ratio of a space d between the first groove and the second groove to the length Lfrom the base end of the vibrating arm to the tip of the second groove, is set between 0.010 and 0.016.

Piezoelectric vibrator

A tuning fork-type crystal vibrator is provided that has improved CI and shock resistance. The tuning fork-type crystal vibrator includes a tuning fork-shaped crystal element made of a pair of tuning fork arms having grooves in their principal surfaces, and a tuning fork base portion from which the pair of tuning fork arms extends, an outer shape of the tuning fork-shaped crystal element being processed by etching. The tuning fork-type crystal vibrator has a protrusion, formed due to anisotropy of said etching, on a +X surface of the lateral faces of the tuning fork-shaped crystal element, and a first slanted portion rising from a &#x2212;X direction in a +X direction formed in a tuning fork slit. A tip of the tuning fork slit on a principal surface side is shifted in +X direction from a center line bisecting the tuning fork-shaped crystal element in a width direction to a position at which tuning fork vibrations of the pair of tuning fork arms are balanced.

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Saitama, Japan

Shingo Kawanishi