Murata Manufacturing Co., Ltd.

Murata Mfg. Co., Ltd.

Hiroshi Nakatani

Jiro Inoue

Hiroaki Kaida

Katsumi Fujimoto

Masatoshi Kajiwara

Katsumi Sakai

Masao Gamo

Masanaga Nishikawa

Toshio Nishimura

Yoshiaki Kohno

Daisuke Nakamura

Eitaro Kameda

Keisuke Takeyama

Kimitoshi Nakamura

Toshiaki Kaji

Masashige Miyamori

Sachio Kitagawa

A piezoelectric resonator unit that includes a base, a cover, and a laminated structure disposed between the base and the cover. The laminated structure includes a piezoelectric resonator having a piezoelectric layer with a pair of principal surfaces facing each other, and a pair of excitation electrodes disposed on respective surfaces of the pair of principal surfaces so as to face each other with the piezoelectric layer therebetween, a semiconductor layer laminated on a side of one of the pair of principal surfaces of the piezoelectric layer, and a pair of measurement electrodes provided on the semiconductor layer. The pair of measurement electrodes measure signals based on temperature of the piezoelectric resonator through the semiconductor layer.

Piezoelectric resonator unit and oscillator provided with the same

A resonator is provided that suppresses vibration of a retainer caused by undesired vibration of a vibrating portion and also achieves size reduction. Specifically, the resonator includes a vibrating member that includes a semiconductor layer, a first piezoelectric film formed on the semiconductor layer, and a first upper electrode formed on the first piezoelectric film. Moreover, a retainer is provided to retain the vibrating member such that the vibrating portion can vibrate and one or more coupling members are provided to couple the vibrating member to the retainer. Finally, the resonator includes a vibration suppressing member that includes a second piezoelectric film formed on the retainer and a second upper electrode formed on the second piezoelectric film.

Resonator and resonating device

A piezoelectric actuator that includes a piezoelectric substrate, first and second electrodes, and a conductive layer. The first and second electrodes are configured to apply a voltage to the piezoelectric substrate. The conductive layer is formed on the first electrode. The conductive layer is made of a metal or an alloy different in color from the second electrode.

Piezoelectric actuator and drive device

A magnetic head driving piezoelectric ceramic actuator having an actuator body and a coating layer. The actuator body has a piezoelectric ceramic substrate and first and second electrodes. The piezoelectric ceramic substrate has first and second principal surfaces, first and second side surfaces, and first and second edge surfaces. The first electrode has a first external electrode portion formed on a part of the first principal surface, and a second external electrode portion formed on the first edge surface. The second electrode has a third external electrode portion formed on the second edge surface, and a fourth external electrode portion formed on the first principal surface. Each of: at least a part of each of the first and second external electrode portions; and at least a part of each of the third and fourth external electrode portions, constitutes a joined portion mounted on the substrate by an electrically-conductive agent. The coating film covers at least a part of a surface of a portion of the actuator body other than the joined portions.

Magnetic head driving piezoelectric ceramic actuator

A multilayer piezoelectric device includes long internal electrodes and short internal electrodes which are arranged so as to extend from a pair of opposing side surfaces of a piezoelectric substrate towards the corresponding side surfaces opposite to the side surfaces from which they extend, and so as to be alternately stacked in the piezoelectric substrate. Active portions are located at portions where the long internal electrodes and the corresponding short internal electrodes are stacked. Further, a first external electrode, connected to the short internal electrodes, is electrically connected to the side surface near the active portions, and a second external electrode, connected to the long internal electrodes, is electrically connected to the side surface distant from the active portions. The first external electrode extends from the side surface of the piezoelectric substrate near the active portions, onto a main surface, and to a location adjacent to the side surface distant from the active portions, while the second external electrode extends onto the main surface so as to be disposed on left and right sides of locations at the first external electrode that are adjacent to the side surface of the piezoelectric substrate distant from the active portions.

Multilayer piezoelectric device and piezoelectric actuator formed using the same

A laminated piezoelectric element includes a second connecting internal electrode electrically connected to a common external electrode that is located in a bottom portion, which lies below the bottoms of slits, of a monolithic piezoelectric body, and the second connecting internal electrode is spaced away from and substantially parallel to the first and second driving internal electrodes. In the laminated piezoelectric element, a notch is formed on a side surface of the monolithic piezoelectric body, having a driving external electrode and a connecting external electrode disposed thereon, and a conducting external electrode is disposed on the side surface of the notch, having an end of the second internal electrode exposed thereat.

Laminated piezoelectric element, method for manufacturing the same, and piezoelectric actuator

A multilayer piezoelectric device includes a piezoelectric layered body having a driving-side external electrode and a connection-side external electrode disposed at one side surface of the piezoelectric layered body, in which a plurality of actuator units are formed by dividing the piezoelectric layered body by a slit extending from the top surface to the bottom surface of the piezoelectric layered body. A cutaway portion is provided in the one side surface of the piezoelectric layered body where the driving-side external electrode and the connection-side external electrode are located so that the cutaway portion is substantially parallel to driving internal electrodes and a connecting internal electrode. The cutaway portion has a width that allows it to reach a location above the bottom end of the slit from the bottom surface of the piezoelectric layered body but that does not allow it to reach the driving internal electrodes.

Multilayer piezoelectric device and method of producing the same and piezoelectric actuator

A piezoelectric actuator is constructed to have a displacement value caused by bending to be added to a usual d,component displacement, thereby increasing the total amount of displacement of the actuator. The actuator includes an actuator body having a layered structure of piezoelectric layers and internal electrodes, and external electrodes disposed on an external surface of the actuator body at both ends thereof. One of the outermost piezoelectric layers is made piezoelectrically active as a result of making an extension portion of the first external electrode, through the one of the outermost piezoelectric layers, face the inner electrodes, to have a polarity which is different from that of the extension portion, while a second of outermost piezoelectric layers is made piezoelectrically inactive as a result of either making an extension portion of the second external electrode facing, through the second of the outermost piezoelectric layers, the inner electrodes, to have a polarity which is identical to that of the extension portion of the second external electrode or as a result of not forming an extension portion on the outer electrode.

Piezoelectric actuator

A monolithic piezoelectric body includes first internal electrodes which extend to a first side surface of the piezoelectric body but do not extend to a second side surface of the piezoelectric body, and second internal electrodes which extend to the second side surface but do not extend to the first side surface. A connecting internal electrode is disposed within the piezoelectric body and extends between the first and second side surfaces. A first external electrode is disposed on the first side surface and is electrically connected to the first internal electrodes. A second external electrode is arranged on the first side surface so as to be separated from the first external electrode and electrically connected to the connecting internal electrode. A third external electrode is disposed on the second side surface so as to electrically connect the second internal electrodes and the connecting internal electrode.

Monolithic piezoelectric body and piezoelectric actuator

Disclosed is a piezoelectric resonator device. This piezoelectric resonator device comprises a piezoelectric substrate having an almost rectangular plane shape. The piezoelectric substrate is provided with a slit extending to the inside from one edge of the piezoelectric substrate, for forming a tuning fork portion, and a pair of slits for separating the tuning fork portion, spaced apart from the slit forming the tuning fork portion by a predetermined distance on both sides of the slit forming the tuning fork portion, and approximately parallel with the slit forming the tuning fork portion. Vibrating electrodes are formed on both major surfaces of the piezoelectric substrate at a piezoelectric vibrating portion, between the slits separating the tuning fork portion from non-vibrating portions of the substrate.

Piezoelectric resonator device of tuning fork type

A tuning fork type piezoelectric resonator constructed by forming tuning fork arm portions on both sides of a first slit provided for a piezoelectric substrate, forming resonance electrodes on both major surfaces of the piezoelectric substrate in a region around the first slit, and forming steps in outer edges of the tuning fork arm portions.

Tuning fork type piezoelectric resonator having steps formed in arms of

Disclosed is a piezoelectric resonator device. This piezoelectric resonator device comprises a piezoelectric substrate having an almost rectangular plane shape. The piezoelectric substrate is provided with a slit extending to the inside from one edge of the piezoelectric substrate, for forming a tuning fork portion, and a pair of slits for separating the tuning fork portion, spaced apart from the slit forming the tuning fork portion by a predetermined distance on both sides of the slit forming the tuning fork portion, and approximately parallel with the slit forming the tuning fork portion. Vibrating electrodes are formed on both major surfaces of the piezoelectric substrate at a piezoelectric vibrating portion between the slits separating the tuning fork portion from non-vibrating portions of the substrate.

Piezoelectric resonator device of tuning fork type including a spacer

A piezoelectric filter of an energy-trapped type utilizing a second harmonic wave of the thickness-extensional vibration mode, characterized in that an earth electrode is formed around the center of a piezoelectric substrate in the direction of thickness, and an input electrode and an output electrode are formed on one or both major surfaces of the piezoelectric substrate so as to be opposed to the earth electrode.

Piezoelectric filter

Disclosed is a piezoelectric resonator device. This piezoelectric resonator device comprises a piezoelectric substrate having an almost rectangular plane shape. The piezoelectric substrate is provided with a slit extending to the inside from one edge of the piezoelectric substrate, for forming a tuning fork portion, a pair of slits for separating the tuning fork portion, spaced apart from the slit forming a tuning fork portion by a predetermined distance on both sides of the slit forming the tuning fork portion, and approximately parallel with the slit forming a tuning fork portion. Vibrating electrodes are formed on both major surfaces of the piezoelectric substrate at a piezoelectric vibrating portion, between the slits separating the tuning fork portion from non-vibrating portions of the substrate.

Growing community of inventors

Omihachiman, Japan

Hiroshi Nakatani