Patents by Inventor Noboru Takizawa
Noboru Takizawa 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).
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Patent number: 11539312Abstract: The present invention provides a motor driver and a motor driving system capable of suppressing power consumption when a motor is in a brake state. The motor driver of the present invention includes: a half-bridge power output section, including a high-side transistor and a low-side transistor; a high-side driving circuit, driving the high-side transistor; and a control portion. When switching to a brake mode, the low-side transistor is turned on and the control portion turns off the high-side driving circuit.Type: GrantFiled: July 30, 2020Date of Patent: December 27, 2022Assignee: Rohm Co., Ltd.Inventors: Tetsuo Yamato, Noboru Takizawa
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Patent number: 11441660Abstract: A hollow strain-wave gear device (1) has a wave generator (5), a wave generator plug (5a) of which is integrally formed in a portion of a hollow rotating shaft (6). A plug reinforcement part (5d), which is adjacent to the wave generator plug (5a), has a thickness larger than that of the wave generator plug (5a), and is integrally formed in the hollow rotating shaft (6). The wave generator plug (5a) is reinforced by the highly rigid plug reinforcement part (5d) formed adjacently to the wave generator plug (5a). It is thus possible to prevent or suppress a decline in the rigidity of the wave generator plug (5a) when the hollow rotating shaft has a thin thickness in order to reduce the weight of the hollow rotating shaft (6) and increase the diameter of the hollow portion thereof. Consequently, it is possible to suppress a decline in ratcheting torque.Type: GrantFiled: June 19, 2018Date of Patent: September 13, 2022Assignee: HARMONIC DRIVE SYSTEMS INC.Inventors: Yutaka Miyazawa, Noboru Takizawa
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Patent number: 11229102Abstract: A lighting device includes light emitting element groups (HSB) including a light emitting element group (HS2) that emits light when being applied with a voltage at a light emission reference voltage (VH2), and a light emitting element group (HS12) that emits light when being applied with a light emission reference voltage (VH12) higher than the light emission reference voltage (VH2), the light emitting element groups (HSB) emitting light when being applied with a voltage equal to or higher than a light emission reference voltage (VHa); a semiconductor chip (IC1) including a light emission control unit (HC1) arranged to perform light emission control to cause light emission of a light emitting element group (HS) if a drive voltage (Vk) is higher than the light emission reference voltage (VHa), and to perform light emission stop control to stop the light emission if the drive voltage (Vk) is lower than the same; and a semiconductor chip (IC2) including a light emission control unit (HC2) arranged to perform ligType: GrantFiled: April 22, 2020Date of Patent: January 18, 2022Assignee: Rohm Co., Ltd.Inventors: Noboru Takizawa, Masaaki Nakayama
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Patent number: 11092223Abstract: An externally toothed gear of a dual-type strain wave gearing is provided with first and second external teeth having different teeth numbers, and a gap formed between these teeth as a cutter clearance area for tooth cutters. The maximum width L1 of the gap is 0.1 to 0.3 times the width L of the externally toothed gear. The depth from the tooth top land of the first external teeth to the deepest part of the gap is 0.9 to 1.3 times the depth of the first external teeth, and the depth from the tooth top land of the second external teeth to the deepest part of the gap is 0.9 to 1.3 times the depth of the second external teeth. The tooth bottom fatigue strength of the externally toothed gear provided with differing numbers of first and second external teeth is increased.Type: GrantFiled: July 3, 2015Date of Patent: August 17, 2021Assignee: HARMONIC DRIVE SYSTEMS INC.Inventors: Jun Handa, Yoshihide Kiyosawa, Noboru Takizawa, Xin Yue Zhang
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Publication number: 20210222764Abstract: A hollow strain-wave gear device (1) has a wave generator (5), a wave generator plug (5a) of which is integrally formed in a portion of a hollow rotating shaft (6). A plug reinforcement part (5d), which is adjacent to the wave generator plug (5a), has a thickness larger than that of the wave generator plug (5a), and is integrally formed in the hollow rotating shaft (6). The wave generator plug (5a) is reinforced by the highly rigid plug reinforcement part (5d) formed adjacently to the wave generator plug (5a). It is thus possible to prevent or suppress a decline in the rigidity of the wave generator plug (5a) when the hollow rotating shaft has a thin thickness in order to reduce the weight of the hollow rotating shaft (6) and increase the diameter of the hollow portion thereof. Consequently, it is possible to suppress a decline in ratcheting torque.Type: ApplicationFiled: June 19, 2018Publication date: July 22, 2021Applicant: HARMONIC DRIVE SYSTEMS INC.Inventors: Yutaka MIYAZAWA, Noboru TAKIZAWA
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Patent number: 10992294Abstract: The present disclosure relates to a driver device, which can drive a load in high temperatures. In a driver IC which drives a motor by switch-driving four output transistors, a gate driving circuit is configured to render a slew rate of a gate voltage of each output transistor to be adjustable at multiple steps while the output transistor is switching. Although a predetermined rate is set to be the slew rate of the gate voltage in a normal state, the slew rate is increased at high temperatures.Type: GrantFiled: September 26, 2019Date of Patent: April 27, 2021Assignee: Rohm Co., Ltd.Inventors: Tetsuo Yamato, Noboru Takizawa
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Publication number: 20210044222Abstract: The present invention provides a motor driver and a motor driving system capable of suppressing power consumption when a motor is in a brake state. The motor driver of the present invention includes: a half-bridge power output section, including a high-side transistor and a low-side transistor; a high-side driving circuit, driving the high-side transistor; and a control portion. When switching to a brake mode, the low-side transistor is turned on and the control portion turns off the high-side driving circuit.Type: ApplicationFiled: July 30, 2020Publication date: February 11, 2021Applicant: ROHM CO., LTD.Inventors: Tetsuo Yamato, Noboru Takizawa
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Patent number: 10890239Abstract: In a silk hat-shaped external gear for a strain wave gearing, t(A)>t(C)>t(D)>t(B) is satisfied, where the thicknesses of the inner circumferential end (A), the middle part (B) and the outer circumferential end (C) of the diaphragm body portion of a diaphragm are t(A), t(B) and t(C), and where the thickness of the barrel-side end part (D) of the curved portion of the diaphragm is t(D). With reference to the thickness of the middle part (B), the thickness of the inner circumferential end (A) of the diaphragm is set so as to be thicker than conventional silk hat-shaped external gears. It is possible to realize an externally toothed gear capable of preventing diaphragm rupture due to thrust force at high load torque and having high fatigue strength.Type: GrantFiled: November 30, 2016Date of Patent: January 12, 2021Assignee: HARMONIC DRIVE SYSTEMS INC.Inventors: Noboru Takizawa, Xin Yue Zhang
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Publication number: 20200253019Abstract: A lighting device includes light emitting element groups (HSB) including a light emitting element group (HS2) that emits light when being applied with a voltage at a light emission reference voltage (VH2), and a light emitting element group (HS12) that emits light when being applied with a light emission reference voltage (VH12) higher than the light emission reference voltage (VH2), the light emitting element groups (HSB) emitting light when being applied with a voltage equal to or higher than a light emission reference voltage (VHa); a semiconductor chip (IC1) including a light emission control unit (HC1) arranged to perform light emission control to cause light emission of a light emitting element group (HS) if a drive voltage (Vk) is higher than the light emission reference voltage (VHa), and to perform light emission stop control to stop the light emission if the drive voltage (Vk) is lower than the same; and a semiconductor chip (IC2) including a light emission control unit (HC2) arranged to perform ligType: ApplicationFiled: April 22, 2020Publication date: August 6, 2020Applicant: Rohm Co., Ltd.Inventors: Noboru Takizawa, Masaaki Nakayama
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Patent number: 10660168Abstract: A lighting device includes light emitting element groups (HSB) including a light emitting element group (HS2) that emits light when being applied with a voltage at a light emission reference voltage (VH2), and a light emitting element group (HS12) that emits light when being applied with a light emission reference voltage (VH12) higher than the light emission reference voltage (VH2), the light emitting element groups (HSB) emitting light when being applied with a voltage equal to or higher than a light emission reference voltage (VHa); a semiconductor chip (IC1) including a light emission control unit (HC1) arranged to perform light emission control to cause light emission of a light emitting element group (HS) if a drive voltage (Vk) is higher than the light emission reference voltage (VHa), and to perform light emission stop control to stop the light emission if the drive voltage (Vk) is lower than the same; and a semiconductor chip (IC2) including a light emission control unit (HC2) arranged to perform ligType: GrantFiled: December 13, 2018Date of Patent: May 19, 2020Assignee: Rohm Co., Ltd.Inventors: Noboru Takizawa, Masaaki Nakayama
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Publication number: 20200106433Abstract: The present disclosure relates to a driver device, which can drive a load in high temperatures. In a driver IC which drives a motor by switch-driving four output transistors, a gate driving circuit is configured to render a slew rate of a gate voltage of each output transistor to be adjustable at multiple steps while the output transistor is switching. Although a predetermined rate is set to be the slew rate of the gate voltage in a normal state, the slew rate is increased at high temperatures.Type: ApplicationFiled: September 26, 2019Publication date: April 2, 2020Inventors: Tetsuo Yamato, Noboru Takizawa
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Publication number: 20190277383Abstract: In a silk hat-shaped external gear for a strain wave gearing, t(A)>t(C)>t(D)>t(B) is satisfied, where the thicknesses of the inner circumferential end (A), the middle part (B) and the outer circumferential end (C) of the diaphragm body portion of a diaphragm are t(A), t(B) and t(C), and where the thickness of the barrel-side end part (D) of the curved portion of the diaphragm is t(D). With reference to the thickness of the middle part (B), the thickness of the inner circumferential end (A) of the diaphragm is set so as to be thicker than conventional silk hat-shaped external gears. It is possible to realize an externally toothed gear capable of preventing diaphragm rupture due to thrust force at high load torque and having high fatigue strength.Type: ApplicationFiled: November 30, 2016Publication date: September 12, 2019Applicant: HARMONIC DRIVE SYSTEMS INC.Inventors: Noboru Takizawa, Xin Yue Zhang
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Patent number: 10393227Abstract: A relieving portion is formed between a first external tooth portion and a second external tooth portion in the external teeth of a flexible externally toothed gear of a flat strain wave gearing. The length L1 of the relieving portion in the tooth trace direction is within the range of 0.1 to 0.5 of the tooth width L of the external teeth. The maximum relieving amount t from the tooth top land of an external tooth in the relieving portion is 3.3×10?4<t/PCD<6.3×10?4 where the PCT is defined as the pitch circle diameter of the external teeth. The tooth face load distribution of the external tooth in the tooth trace direction can be equalized, and a flat strain wave gearing having a high transmitted-load capacity can be achieved.Type: GrantFiled: August 6, 2014Date of Patent: August 27, 2019Assignee: Harmonic Drive Systems Inc.Inventors: Jun Handa, Yoshihide Kiyosawa, Noboru Takizawa, Xin Yue Zhang
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Patent number: 10352427Abstract: In the cup-shaped externally toothed gear, the outside end face profile of the diaphragm is defined by a first concave circular arc having a first radius, a second concave circular arc that has a second radius and is smoothly connected to the first concave circular arc, an inclined straight line that is smoothly connected to the second concave circular arc and is inclined toward an inside straight line with respect to the center axis line, the inside straight line defining the outside profile of the diaphragm. The second radius is larger than the first radius, and the thickness of the diaphragm is gradually decreased from the side of the boss to the side of the cylindrical body. The stress concentration in the boss-side joint portion of the diaphragm can be relieved, whereby enhancing fatigue strength of the flexible externally toothed gear.Type: GrantFiled: January 18, 2017Date of Patent: July 16, 2019Assignee: Harmonic Drive Systems Inc.Inventors: Noboru Takizawa, Go Kuroiwa
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Publication number: 20190203819Abstract: An externally toothed gear of a dual-type strain wave gearing is provided with first and second external teeth having different teeth numbers, and a gap formed between these teeth as a cutter clearance area for tooth cutters. The maximum width L1 of the gap is 0.1 to 0.3 times the width L of the externally toothed gear. The depth from the tooth top land of the first external teeth to the deepest part of the gap is 0.9 to 1.3 times the depth of the first external teeth, and the depth from the tooth top land of the second external teeth to the deepest part of the gap is 0.9 to 1.3 times the depth of the second external teeth. The tooth bottom fatigue strength of the externally toothed gear provided with differing numbers of first and second external teeth is increased.Type: ApplicationFiled: July 3, 2015Publication date: July 4, 2019Applicant: HARMONIC DRIVE SYSTEMS INC.Inventors: Jun HANDA, Yoshihide KIYOSAWA, Noboru TAKIZAWA, Xin Yue ZHANG
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Patent number: 10309513Abstract: An externally toothed gear of a dual-type strain wave gearing is provided with first and second external teeth having different teeth numbers, and is flexed into an ellipsoidal shape by a wave generator. When the theoretical values of the radial flexing amounts at major-axis positions of the first and second external teeth flexed into the ellipsoidal shape are expressed by d1=m1n1 and d2=m2n2 (m1 and m2 represent the modules of the first and second external teeth, and n1 and n2 represent positive integers), the radial flexing amounts of the first and second external teeth flexed by the wave generator satisfy d1a=?d1 and d2a=?d2, where 1.25???3. Accordingly, a dual-type strain wave gearing can be achieved with which the first and second external teeth having different numbers can be suitably flexed to form excellent mating states with respective internally toothed gears.Type: GrantFiled: July 3, 2015Date of Patent: June 4, 2019Assignee: Harmonic Drive Systems Inc.Inventors: Yoshihide Kiyosawa, Jun Handa, Noboru Takizawa, XinYue Zhang
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Patent number: 10295037Abstract: An externally toothed gear of a dual-type strain wave gearing is provided with first and second external teeth having different tooth numbers, and is flexed into an ellipsoidal shape by a wave generator. When the theoretical values of the radial flexing amounts at major-axis positions of the first and second external teeth flexed into the ellipsoidal shape are expressed by d1=m1n1 and d2=m2n2 (m1 and m2 represent the modules of the first and second external teeth, and n1 and n2 represent positive integers), the radial flexing amount of the first and second external teeth flexed by the wave generator satisfies d=(d1+d2)/?(1.4???2.6). Accordingly, a dual-type strain wave gearing can be achieved with which the first and second external teeth having different numbers can be suitably flexed to form excellent mating states with respective internally toothed gears.Type: GrantFiled: July 3, 2015Date of Patent: May 21, 2019Assignee: Harmonic Drive Systems Inc.Inventors: Yoshihide Kiyosawa, Jun Handa, Noboru Takizawa, XinYue Zhang
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Publication number: 20190116639Abstract: A lighting device includes light emitting element groups (HSB) including a light emitting element group (HS2) that emits light when being applied with a voltage at a light emission reference voltage (VH2), and a light emitting element group (HS12) that emits light when being applied with a light emission reference voltage (VH12) higher than the light emission reference voltage (VH2), the light emitting element groups (HSB) emitting light when being applied with a voltage equal to or higher than a light emission reference voltage (VHa); a semiconductor chip (IC1) including a light emission control unit (HC1) arranged to perform light emission control to cause light emission of a light emitting element group (HS) if a drive voltage (Vk) is higher than the light emission reference voltage (VHa), and to perform light emission stop control to stop the light emission if the drive voltage (Vk) is lower than the same; and a semiconductor chip (IC2) including a light emission control unit (HC2) arranged to perform ligType: ApplicationFiled: December 13, 2018Publication date: April 18, 2019Applicant: Rohm Co., Ltd.Inventors: Noboru Takizawa, Masaaki Nakayama
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Patent number: 10253863Abstract: An externally toothed gear of a dual-type strain wave gearing is provided with first and second external teeth having different teeth numbers. The first and second external teeth are flexed by a wave generator by the same flexing amount, into an ellipsoidal shape. The tooth depth of tooth profiles of the first external teeth having a low teeth number is smaller than the tooth depth of tooth profiles of the second external teeth having a high teeth number. A dual-type strain wave gearing can be achieved with which the first and second external teeth having different teeth numbers can be suitably flexed to form excellent meshing states with respective internally toothed gears.Type: GrantFiled: July 3, 2015Date of Patent: April 9, 2019Assignee: HARMONIC DRIVE SYSTEMS INC.Inventors: Yoshihide Kiyosawa, Jun Handa, XinYue Zhang, Noboru Takizawa
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Patent number: 10253862Abstract: An externally toothed gear of a dual-type strain wave gearing is provided with first and second external teeth having different teeth numbers, and is flexed into an ellipsoidal shape by a wave generator. When t(1) represents the tooth bottom rim wall thickness of the first external teeth, and t(2) represents the tooth bottom rim wall thickness of the second external teeth, the ratio of t(1)/t(2) is set to a value satisfying 0.5>t(1)/t(2)<1.5. Accordingly, a dual-type strain wave gearing can be achieved with which the first and second external teeth having different teeth numbers can be suitably flexed to form excellent meshing states with respective internally toothed gears.Type: GrantFiled: July 3, 2015Date of Patent: April 9, 2019Assignee: Harmonic Drive Systems Inc.Inventors: Yoshihide Kiyosawa, Jun Handa, Noboru Takizawa, Xin Yue Zhang