Patents by Inventor Nobuyuki Ishitoko
Nobuyuki Ishitoko has filed for patents to protect the following inventions. This listing includes patent applications that are pending as well as patents that have already been granted by the United States Patent and Trademark Office (USPTO).
-
Patent number: 6898973Abstract: A vibrating gyroscope includes a vibrator which is retained by supporting members at one end of the supporting members and a housing to which the supporting members are fixed at the other end of the supporting members. A rigid reinforcing plate made of a metal is embedded in the housing made of a resin by insert molding. The rigid reinforcing plate is continuous between positions near fixing portions at which the supporting members are fixed to the housing. Therefore, the rigidity of the housing is increased and the vibration of the vibrator is prevented from being transmitted to the outside. In addition, the temperature drift performance is prevented from being degraded.Type: GrantFiled: November 27, 2002Date of Patent: May 31, 2005Assignee: Murata Manufacturing Co., Ltd.Inventor: Nobuyuki Ishitoko
-
Patent number: 6722622Abstract: A compact vibrator support structure has a very high “vibration confinement effect”, and includes a vibrator, vibrator support members, and a vibrator base, which supports the vibrator in midair via the vibrator support members and is made of a material having a specific gravity of about 3.0 or above. Since the high vibration confinement effect of the vibrator support structure reduces leakage of vibration from the vibrator base, the stability of the vibration of the vibrator is greatly improved, thereby increasing the detecting accuracy of angular velocity. This eliminates the need to enlarge the vibrator base or to adhere a weight thereto, resulting in a miniaturized vibrating gyroscope.Type: GrantFiled: February 26, 2002Date of Patent: April 20, 2004Assignee: Murata Manufacturing Co., Ltd.Inventors: Akira Mori, Nobuyuki Ishitoko
-
Patent number: 6720714Abstract: A vibrating gyroscope includes a vibrator having a node and a support member having a thin flexible portion and an expanded portion which is connected to the thin flexibly portion and has a larger area than the thin flexible portion. The expanded portion of the support member is fixed to the vibrator at the node.Type: GrantFiled: September 10, 2001Date of Patent: April 13, 2004Assignee: Murata Manufacturing Co., Ltd.Inventors: Nobuyuki Ishitoko, Katsumi Fujimoto, Yoshiji Okamoto, Hirofumi Tanaka
-
Patent number: 6680559Abstract: A vibration gyroscope includes a vibrator base that supports a vibrator in a hollow portion of the base and includes a frame-shaped portion. Protrusion portions are provided on the inner wall of the frame-shaped portion which defines a stopper that restricts displacement of the vibrator beyond a desired distance. The frame-shaped portion and the protrusion portions are integrally formed by a two-color molding method to define a single unitary member.Type: GrantFiled: March 26, 2002Date of Patent: January 20, 2004Assignee: Murata Manufacturing Co., Ltd.Inventors: Nobuyuki Ishitoko, Katsumi Fujimoto
-
Patent number: 6668649Abstract: In order to provide a vibrating gyroscope in which variations in the angular-velocity detection sensitivity are not likely to occur even when sharp temperature changes occur, a vibrator for a vibrating gyroscope includes, on one main surface, a first detection electrode and a second detection electrode, which output a signal containing an angular-velocity signal, wherein a groove having a predetermined depth is provided between the first detection electrode and the second detection electrode. As for a vibrator for a vibrating gyroscope of the present invention, since the difference between the resonance frequency and the anti-resonance frequency in a bending vibration mode in the driving direction becomes closer to the difference between the resonance frequency and the anti-resonance frequency in a bending vibration mode in the detection direction, variations in the angular-velocity detection sensitivity are not likely to occur even when sharp temperature changes are given.Type: GrantFiled: June 14, 2001Date of Patent: December 30, 2003Assignee: Murata Manufacturing Co., Ltd.Inventors: Nobuyuki Ishitoko, Masato Koike
-
Patent number: 6634230Abstract: A vibrating gyroscope includes supporting members which are fixed in the vicinity of two node axes n1 and n2 of a bar-shaped vibrator. The supporting members corresponding to node axis n1 extend from the locations at which they are fixed to the vibrator in the widthwise direction of the vibrator, and also include bending portions and a proximity portion. The bending portions bend toward node axis n1. At the proximity portion, the supporting members are in close proximity with each other with a gap therebetween in the vicinity of node axis n1.Type: GrantFiled: April 18, 2002Date of Patent: October 21, 2003Assignee: Murata Manufacturing Co., Ltd.Inventors: Isao Toyoshima, Akira Mori, Nobuyuki Ishitoko, Takayuki Shimamoto, Akira Kumada, Iku Nagai
-
Patent number: 6590316Abstract: The present invention provides a piezoelectric vibrator, in which there is no significant change in the characteristics even when depole occurs due to heat shock and the like. The piezoelectric vibrator includes a first piezoelectric substrate having split electrodes formed on one main surface thereof and a second piezoelectric substrate having a common electrode formed on one main surface thereof. The remaining main surfaces of both piezoelectric substrates are bonded to each other via an intermediate electrode. The material of the first piezoelectric substrate differs from the material of the second piezoelectric substrate. As a result, the difference (longitudinal DF) between a resonant frequency and an anti-resonant frequency in a longitudinal vibration of the piezoelectric vibrator substantially coincides with the difference (transverse DF) between a resonant frequency and an anti-resonant frequency in a transverse vibration thereof.Type: GrantFiled: December 26, 2001Date of Patent: July 8, 2003Assignee: Murata Manufacturing Co., Ltd.Inventors: Masato Koike, Katsumi Fujimoto, Nobuyuki Ishitoko
-
Publication number: 20030101816Abstract: A vibrating gyroscope includes a vibrator which is retained by supporting members at one end of the supporting members and a housing to which the supporting members are fixed at the other end of the supporting members. A rigid reinforcing plate made of a metal is embedded in the housing made of a resin by insert molding. The rigid reinforcing plate is continuous between positions near fixing portions at which the supporting members are fixed to the housing. Therefore, the rigidity of the housing is increased and the vibration of the vibrator is prevented from being transmitted to the outside. In addition, the temperature drift performance is prevented from being degraded.Type: ApplicationFiled: November 27, 2002Publication date: June 5, 2003Inventor: Nobuyuki Ishitoko
-
Publication number: 20020166381Abstract: A vibrating gyroscope includes supporting members which are fixed in the vicinity of two node axes n1 and n2 of a bar-shaped vibrator. The supporting members corresponding to node axis n1 extend from the locations at which they are fixed to the vibrator in the widthwise direction of the vibrator, and also include bending portions and a proximity portion. The bending portions bend toward node axis n1. At the proximity portion, the supporting members are in close proximity with each other with a gap therebetween in the vicinity of node axis n1.Type: ApplicationFiled: April 18, 2002Publication date: November 14, 2002Applicant: Murata Manufacturing Co., Ltd.Inventors: Isao Toyoshima, Akira Mori, Nobuyuki Ishitoko, Takayuki Shimamoto, Akira Kumada, Iku Nagai
-
Publication number: 20020134155Abstract: A vibration gyroscope includes a vibrator base that supports a vibrator in a hollow portion of the base and includes a frame-shaped portion. Protrusion portions are provided on the inner wall of the frame-shaped portion which defines a stopper that restricts displacement of the vibrator beyond a desired distance. The frame-shaped portion and the protrusion portions are integrally formed by a two-color molding method to define a single unitary member.Type: ApplicationFiled: March 26, 2002Publication date: September 26, 2002Inventors: Nobuyuki Ishitoko, Katsumi Fujimoto
-
Publication number: 20020125795Abstract: A compact vibrator support structure has a very high “vibration confinement effect”, and includes a vibrator, vibrator support members, and a vibrator base, which supports the vibrator in midair via the vibrator support members and is made of a material having a specific gravity of about 3.0 or above. Since the high vibration confinement effect of the vibrator support structure reduces leakage of vibration from the vibrator base, the stability of the vibration of the vibrator is greatly improved, thereby increasing the detecting accuracy of angular velocity. This eliminates the need to enlarge the vibrator base or to adhere a weight thereto, resulting in a miniaturized vibrating gyroscope.Type: ApplicationFiled: February 26, 2002Publication date: September 12, 2002Inventors: Akira Mori, Nobuyuki Ishitoko
-
Patent number: 6418789Abstract: A vibrating gyroscope includes: a support; four vibrating arms, four weights and excitation and detection elements. Each of the four vibrating arms has a first end and a second end in a longitudinal direction, and the four vibrating arms are fixed to the support at the respective first ends in the longitudinal direction such that four vibrating arms are radially arranged in a single plane with the adjacent arms making an angle of about 90 degrees. The four weights are fixed to the support so as to be arranged radially between the respective adjacent vibrating arms. The excitation and detection elements vibrate the vibrating arms under a bending mode within the single plane and output signals generated by the vibration of the vibrating arms.Type: GrantFiled: February 8, 2000Date of Patent: July 16, 2002Assignee: Murata Manufacturing Co., Ltd.Inventors: Nobuyuki Ishitoko, Katsumi Fujimoto
-
Publication number: 20020089260Abstract: The present invention provides a piezoelectric vibrator, in which there is no significant change in the characteristics even when depole occurs due to heat shock and the like. The piezoelectric vibrator includes a first piezoelectric substrate having split electrodes formed on one main surface thereof and a second piezoelectric substrate having a common electrode formed on one main surface thereof. The remaining main surfaces of both piezoelectric substrates are bonded to each other via an intermediate electrode. The material of the first piezoelectric substrate differs from the material of the second piezoelectric substrate. As a result, the difference (longitudinal DF) between a resonant frequency and an anti-resonant frequency in a longitudinal vibration of the piezoelectric vibrator substantially coincides with the difference (transverse DF) between a resonant frequency and an anti-resonant frequency in a transverse vibration thereof.Type: ApplicationFiled: December 26, 2001Publication date: July 11, 2002Applicant: Murata Manufacturing Co., Ltd.Inventors: Masato Koike, Katsumi Fujimoto, Nobuyuki Ishitoko
-
Publication number: 20020047502Abstract: A vibrating gyroscope includes a vibrator having a node and a support member having a thin flexible portion and an expanded portion which is connected to the thin flexibly portion and has a larger area than the thin flexible portion. The expanded portion of the support member is fixed to the vibrator at the node.Type: ApplicationFiled: September 10, 2001Publication date: April 25, 2002Applicant: Murata Manufacturing Co., Ltd.Inventors: Nobuyuki Ishitoko, Katsumi Fujimoto, Yoshiji Okamoto, Hirofumi Tanaka
-
Publication number: 20020020218Abstract: In order to provide a vibrating gyroscope in which variations in the angular-velocity detection sensitivity are not likely to occur even when sharp temperature changes occur, a vibrator for a vibrating gyroscope includes, on one main surface, a first detection electrode and a second detection electrode, which output a signal containing an angular-velocity signal, wherein a groove having a predetermined depth is provided between the first detection electrode and the second detection electrode. As for a vibrator for a vibrating gyroscope of the present invention, since the difference between the resonance frequency and the anti-resonance frequency in a bending vibration mode in the driving direction becomes closer to the difference between the resonance frequency and the anti-resonance frequency in a bending vibration mode in the detection direction, variations in the angular-velocity detection sensitivity are not likely to occur even when sharp temperature changes are given.Type: ApplicationFiled: June 14, 2001Publication date: February 21, 2002Applicant: Murata Manufacturing Co., Ltd.Inventors: Nobuyuki Ishitoko, Masato Koike
-
Patent number: 6288478Abstract: A vibrating gyroscope includes a vibrator having a node and a support member having a thin flexible portion and an expanded portion which is connected to the thin flexibly portion and has a larger area than the thin flexible portion. The expanded portion of the support member is fixed to the vibrator at the node.Type: GrantFiled: May 28, 1998Date of Patent: September 11, 2001Assignee: Murata Manufacturing Co. Ltd.Inventors: Nobuyuki Ishitoko, Katsumi Fujimoto, Yoshiji Okamoto, Hirofumi Tanaka
-
Patent number: 6281618Abstract: A vibrating gyroscope includes two planar vibrating plates arranged to oppose each other. The two vibrating plates vibrate under buckling vibration mode and a second-order bending vibration mode which is degenerated with or close to the buckling vibration mode. The vibrating gyroscope detects Coriolis force by detecting displacements in amplitude balance of the second-order bending vibration modes generated when an angular rotation velocity around an axis parallel to surfaces of the vibrating plates is applied.Type: GrantFiled: April 17, 2000Date of Patent: August 28, 2001Assignee: Murata Manufactuirng Co., Ltd.Inventors: Nobuyuki Ishitoko, Katsumi Fujimoto
-
Patent number: 6089087Abstract: A vibrating gyroscope includes a vibration member in which first and second piezoelectric substrates are joined together. On the outside main surface of the first piezoelectric substrate, a first external electrode divided into six electrode sections is formed. On the outside main surface of the second piezoelectric substrate, a second external electrode is formed. By removing a part of the electrode sections disposed at the center, a capacitance difference C(L)-C(R) between the capacitance C(L) formed between one of the electrode sections disposed at the center and the second external electrode, and the capacitance C(R) formed between another electrode section disposed at the center and the second external electrode is adjusted.Type: GrantFiled: September 30, 1997Date of Patent: July 18, 2000Assignee: Murata Manufacturing Co., Ltd.Inventors: Katsumi Fujimoto, Nobuyuki Ishitoko
-
Patent number: 6058777Abstract: A vibrating gyroscope includes a vibrating unit and a driving unit for driving the vibrating unit. The vibrating unit includes at least a pair of piezoelectric bodies stacked and polarized in a stacked direction thereof such that polarizing directions of the piezoelectric bodies are opposed to each other. An interface between the piezoelectric bodies is electrically floating with respect to a reference potential. The driving circuit receives at least one feedback signal from the vibrating unit and outputs to the vibrating unit a driving signal which has substantially the same phase as the feedback signal.Type: GrantFiled: February 19, 1998Date of Patent: May 9, 2000Assignee: Murata Manufacturing Co., Ltd.Inventors: Katsumi Fujimoto, Kazuhiro Ebara, Nobuyuki Ishitoko
-
Patent number: 6023973Abstract: A vibrating gyroscope includes a columnar vibrator, a driver and a detector. The columnar vibrator includes first and second piezoelectric substrates polarized in mutually opposite directions along the thickness directions thereof and stacked with each other. Two divided electrodes are formed on one main surface of the first piezoelectric substrate and spaced in the direction perpendicular to the longitudinal direction of the first piezoelectric substrate, and a common electrode is formed on one main surface of the second piezoelectric substrate. The driver drives the vibrator in the thickness direction of the first and second piezoelectric substrates and is connected between the divided electrodes and the common electrode. The detector detects a displacement caused by bending vibration of the vibrator, and is connected to the divided electrodes.Type: GrantFiled: September 3, 1998Date of Patent: February 15, 2000Assignee: Murata Manufacturing Co., Ltd.Inventors: Toru Yabe, Katsuhiko Morita, Tetsuo Tatsumi, Nobuyuki Ishitoko, Michihiko Takenaka