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).

  • Patent number: 11539312
    Abstract: 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: Grant
    Filed: July 30, 2020
    Date of Patent: December 27, 2022
    Assignee: Rohm Co., Ltd.
    Inventors: Tetsuo Yamato, Noboru Takizawa
  • Patent number: 11441660
    Abstract: 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: Grant
    Filed: June 19, 2018
    Date of Patent: September 13, 2022
    Assignee: HARMONIC DRIVE SYSTEMS INC.
    Inventors: Yutaka Miyazawa, Noboru Takizawa
  • Patent number: 11229102
    Abstract: 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 lig
    Type: Grant
    Filed: April 22, 2020
    Date of Patent: January 18, 2022
    Assignee: Rohm Co., Ltd.
    Inventors: Noboru Takizawa, Masaaki Nakayama
  • Patent number: 11092223
    Abstract: 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: Grant
    Filed: July 3, 2015
    Date of Patent: August 17, 2021
    Assignee: HARMONIC DRIVE SYSTEMS INC.
    Inventors: Jun Handa, Yoshihide Kiyosawa, Noboru Takizawa, Xin Yue Zhang
  • Publication number: 20210222764
    Abstract: 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: Application
    Filed: June 19, 2018
    Publication date: July 22, 2021
    Applicant: HARMONIC DRIVE SYSTEMS INC.
    Inventors: Yutaka MIYAZAWA, Noboru TAKIZAWA
  • Patent number: 10992294
    Abstract: 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: Grant
    Filed: September 26, 2019
    Date of Patent: April 27, 2021
    Assignee: Rohm Co., Ltd.
    Inventors: Tetsuo Yamato, Noboru Takizawa
  • Publication number: 20210044222
    Abstract: 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: Application
    Filed: July 30, 2020
    Publication date: February 11, 2021
    Applicant: ROHM CO., LTD.
    Inventors: Tetsuo Yamato, Noboru Takizawa
  • Patent number: 10890239
    Abstract: 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: Grant
    Filed: November 30, 2016
    Date of Patent: January 12, 2021
    Assignee: HARMONIC DRIVE SYSTEMS INC.
    Inventors: Noboru Takizawa, Xin Yue Zhang
  • Publication number: 20200253019
    Abstract: 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 lig
    Type: Application
    Filed: April 22, 2020
    Publication date: August 6, 2020
    Applicant: Rohm Co., Ltd.
    Inventors: Noboru Takizawa, Masaaki Nakayama
  • Patent number: 10660168
    Abstract: 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 lig
    Type: Grant
    Filed: December 13, 2018
    Date of Patent: May 19, 2020
    Assignee: Rohm Co., Ltd.
    Inventors: Noboru Takizawa, Masaaki Nakayama
  • Publication number: 20200106433
    Abstract: 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: Application
    Filed: September 26, 2019
    Publication date: April 2, 2020
    Inventors: Tetsuo Yamato, Noboru Takizawa
  • Publication number: 20190277383
    Abstract: 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: Application
    Filed: November 30, 2016
    Publication date: September 12, 2019
    Applicant: HARMONIC DRIVE SYSTEMS INC.
    Inventors: Noboru Takizawa, Xin Yue Zhang
  • Patent number: 10393227
    Abstract: 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: Grant
    Filed: August 6, 2014
    Date of Patent: August 27, 2019
    Assignee: Harmonic Drive Systems Inc.
    Inventors: Jun Handa, Yoshihide Kiyosawa, Noboru Takizawa, Xin Yue Zhang
  • Patent number: 10352427
    Abstract: 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: Grant
    Filed: January 18, 2017
    Date of Patent: July 16, 2019
    Assignee: Harmonic Drive Systems Inc.
    Inventors: Noboru Takizawa, Go Kuroiwa
  • Publication number: 20190203819
    Abstract: 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: Application
    Filed: July 3, 2015
    Publication date: July 4, 2019
    Applicant: HARMONIC DRIVE SYSTEMS INC.
    Inventors: Jun HANDA, Yoshihide KIYOSAWA, Noboru TAKIZAWA, Xin Yue ZHANG
  • Patent number: 10309513
    Abstract: 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: Grant
    Filed: July 3, 2015
    Date of Patent: June 4, 2019
    Assignee: Harmonic Drive Systems Inc.
    Inventors: Yoshihide Kiyosawa, Jun Handa, Noboru Takizawa, XinYue Zhang
  • Patent number: 10295037
    Abstract: 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: Grant
    Filed: July 3, 2015
    Date of Patent: May 21, 2019
    Assignee: Harmonic Drive Systems Inc.
    Inventors: Yoshihide Kiyosawa, Jun Handa, Noboru Takizawa, XinYue Zhang
  • Publication number: 20190116639
    Abstract: 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 lig
    Type: Application
    Filed: December 13, 2018
    Publication date: April 18, 2019
    Applicant: Rohm Co., Ltd.
    Inventors: Noboru Takizawa, Masaaki Nakayama
  • Patent number: 10253863
    Abstract: 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: Grant
    Filed: July 3, 2015
    Date of Patent: April 9, 2019
    Assignee: HARMONIC DRIVE SYSTEMS INC.
    Inventors: Yoshihide Kiyosawa, Jun Handa, XinYue Zhang, Noboru Takizawa
  • Patent number: 10253862
    Abstract: 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: Grant
    Filed: July 3, 2015
    Date of Patent: April 9, 2019
    Assignee: Harmonic Drive Systems Inc.
    Inventors: Yoshihide Kiyosawa, Jun Handa, Noboru Takizawa, Xin Yue Zhang