Patents by Inventor Tsutomu Shiga

Tsutomu Shiga 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: 7660704
    Abstract: A method and apparatus for designing a screw-tightening element are disclosed for designing the screw-tightening element (mechanical element). The design method comprises representing material characteristics of the screw component with factors including at least one of an elastic limit, an endurance strength, a true breaking power and a tension strength, representing a material characteristic of the tightening object with a factor including an elastic limit, providing a plurality of damage patterns associated with the material characteristics of the screw component and the tightening object, and calculating tolerance values of fluctuating loads in the plurality of damage patterns based on the material characteristics of the screw-tightening element and the elastic limit of the tightening object. The tolerance values of fluctuating loads are compared to determine an optimum tolerance load for the screw-tightening element.
    Type: Grant
    Filed: September 28, 2006
    Date of Patent: February 9, 2010
    Assignee: Denso Corporation
    Inventor: Tsutomu Shiga
  • Patent number: 7646123
    Abstract: A vehicle alternator for generating electric power is driven by an engine mounted on a vehicle driven through a driving belt. The alternator has a pulley part joined to and directly receiving a driving force from the engine through the driving belt, a field magnet part located in separation from the pulley part, a rotation speed changing part placed between the pulley part and the field magnet part. The rotation speed changing part converts the number of revolutions between the pulley part and the field magnet part. The rotation speed changing part decreases a speed changing ratio “S” according to increasing of the number of revolutions of the engine, where the speed changing ratio “S” is obtained by dividing the number of revolutions of the field magnet part by the number of revolutions of the pulley part.
    Type: Grant
    Filed: October 13, 2006
    Date of Patent: January 12, 2010
    Assignee: Denso Corporation
    Inventors: Kouichi Ihata, Atsushi Umeda, Tsutomu Shiga
  • Patent number: 7618193
    Abstract: A rolling bearing is adapted for an auxiliary device driven by an internal combustion engine via a belt. The rolling bearing comprises an inner race, an outer race, and a plurality of rolling elements disposed between the inner race and the outer race for rolling capabilities. A substantially half of a tolerance value of a clearance in a radial direction of the rolling bearing falls in a negative value, under a condition where the rolling bearing is mounted in the auxiliary device.
    Type: Grant
    Filed: April 17, 2006
    Date of Patent: November 17, 2009
    Assignee: Denso Corporation
    Inventors: Atsushi Umeda, Tsutomu Shiga, Kouichi Ihata
  • Patent number: 7577555
    Abstract: A method of designing a roller bearing is disclosed upon clarifying mechanisms of damage patterns in respect of two kinds of brinelling, involved in the bearing, wherein white-banded flaking (brittle flaking) is a plastic instability phenomenon appearing under high-speed deformation accompanied by adiabatic shear deformation status with the resultant occurrence of adiabatic shear band (also called white band) inside material of the bearing. This enables all of the damage patterns to be determined upon making comparison between shear strain and shear strain rate, occurring inside the bearing, and discriminated values.
    Type: Grant
    Filed: July 26, 2006
    Date of Patent: August 18, 2009
    Assignee: Denso Corporation
    Inventors: Atsushi Umeda, Tsutomu Shiga, Kouichi Ihata
  • Patent number: 7560837
    Abstract: An automotive alternator includes a rotary shaft, a pulley, a stator, a rotor, and a magnetic fluctuation suppressor. The pulley is provided on the rotary shaft to transmit rotating power from an engine to the rotary shaft. The stator includes a stator winding. The rotor is mounted on the rotary shaft and configured to provide a first rotating magnetic field to the stator. The magnetic fluctuation suppressor includes a magnetic body and a magnetic source. The magnetic body is mounted on the rotary shaft such that the magnetic body is rotatable along with the rotary shaft at a rotational speed different from that of the rotary shaft. The magnetic source is fixed to the rotary shaft so as to create a second rotating magnetic field which induces a magnetic attraction between the magnetic body and the magnetic source, by which fluctuations in rotational movement of the rotary shaft are suppressed.
    Type: Grant
    Filed: November 14, 2005
    Date of Patent: July 14, 2009
    Assignee: Denso Corporation
    Inventors: Atsushi Umeda, Tsutomu Shiga, Kouichi Ihata
  • Patent number: 7535140
    Abstract: An on-vehicle alternator is disclosed having a rotor driven by an engine via a belt, a stator having armature windings to generate electromotive forces in response to rotating magnetic fluxes, a housing on which the stator is fixedly secured, a pulley fixedly supported on the rotor to transmit a belt drive force to the rotor, and bearings rotatably supporting the rotor and fixedly supported on the housing. The power generator also includes a bush, formed of a metallic member, which is accommodated in the housing. The bearing, disposed in an area closer to the pulley, is comprised of an inner race, an outer race and rolling elements, all of which are formed of metallic members, with the outer race being press fitted to the bush with a certain degree of interference.
    Type: Grant
    Filed: June 13, 2006
    Date of Patent: May 19, 2009
    Assignee: Denso Corporation
    Inventors: Nakato Murata, Atsushi Umeda, Tsutomu Shiga
  • Patent number: 7520675
    Abstract: A rolling bearing assembly according to the present invention includes an inner ring, an outer ring, a plurality of rolling elements interposed between the inner and outer rings, and a magnet provided to cause magnetic attraction between the rolling elements and at least one of the inner and outer rings. With the magnetic attraction, it is possible to avoid any collision between the rolling elements and the inner and outer rings, thereby preventing brittle flaking from occurring in the rolling bearing assembly.
    Type: Grant
    Filed: March 2, 2006
    Date of Patent: April 21, 2009
    Assignee: Denso Corporation
    Inventors: Kouichi Ihata, Tsutomu Shiga, Atsushi Umeda
  • Patent number: 7375500
    Abstract: A method of calculating torque of a Lundell-type synchronous generator is disclosed in which only power generation output current and a rotational speed are input for calculation of the amount of electric power and the amount of losses for thereby enabling calculation of power generating torque, based on a sum of the amount of electric power and the amount of losses, which is generated as an output. The present method establishes formulae enabling calculation based on only output current and the rotational speed, enabling a minimal number of inputs to shorten a calculation time interval.
    Type: Grant
    Filed: July 28, 2006
    Date of Patent: May 20, 2008
    Assignee: Denso Corporation
    Inventors: Atsushi Umeda, Tsutomu Shiga, Kouichi Ihata
  • Patent number: 7337687
    Abstract: A starter for cranking an internal combustion engine is composed of an electric motor, an output shaft driven by the electric motor, a pinion gear unit helical-spline-coupled to the output shaft, and a magnetic switch for supplying electric power to the electric motor in an ON-and-OFF fashion and for engaging or disengaging the pinion gear unit with a ring gear of the engine. The pinion gear unit is made by fixedly connecting a pinion gear, a rotation-restricting ring and a bearing member together. These components are separately formed from one another and then assembled to a unitary body of the pinion gear unit. Therefore, they can be forged with simple dies, or may be manufactured by other methods such as machining.
    Type: Grant
    Filed: April 15, 2004
    Date of Patent: March 4, 2008
    Assignee: Denso Corporation
    Inventors: Kazushige Okumoto, Masami Niimi, Tsutomu Shiga
  • Patent number: 7302750
    Abstract: An armature of a rotary electric machine composed of an armature core, an armature winding and a shaft is manufactured in the following manner. A conductor bar including plural conductors connected in line is formed, and each conductor is cut out from the conductor bar. The conductor in a straight shape is inserted into each slot of the armature core, and then both side portions of the conductor are bent at substantially right angle so that the side portions are positioned along axial end surfaces of the armature core. The side portions are further skewed and electrically connected to form the armature winding. An outer surface of the side portions circularly arranged on the axial end surface of the armature core is used as a commutator surface.
    Type: Grant
    Filed: July 12, 2004
    Date of Patent: December 4, 2007
    Assignee: Denso Corporation
    Inventors: Masami Niimi, Tsutomu Shiga, Masanori Oomi
  • Patent number: 7284314
    Abstract: In a method of manufacturing a rotor of a rotary electric machine, a rotor core is formed by preparing a material sheet in a form of a belt. The material sheet has teeth extending from a first side of a middle portion of the material sheet and projections projecting from a second side of the middle portion in a direction opposite to the teeth. The projections define recesses therebetween. Each projection and each recess has substantially the same dimension with respect to a centerline between a first line passing through tops of the projections and a second line passing through bottoms of the recesses. The material sheet is helically wound so that the projections are located on an inner diameter side of a rotor core.
    Type: Grant
    Filed: December 22, 2005
    Date of Patent: October 23, 2007
    Assignee: Denso Corporation
    Inventors: Masami Niimi, Tsutomu Shiga, Masanori Ohmi
  • Publication number: 20070102932
    Abstract: A vehicle alternator for generating electric power is driven by an engine mounted on a vehicle driven through a driving belt. The alternator has a pulley part joined to and directly receiving a driving force from the engine through the driving belt, a field magnet part located in separation from the pulley part, a rotation speed changing part placed between the pulley part and the field magnet part. The rotation speed changing part converts the number of revolutions between the pulley part and the field magnet part. The rotation speed changing part decreases a speed changing ratio “S” according to increasing of the number of revolutions of the engine, where the speed changing ratio “S” is obtained by dividing the number of revolutions of the field magnet part by the number of revolutions of the pulley part.
    Type: Application
    Filed: October 13, 2006
    Publication date: May 10, 2007
    Applicant: DENSO CORPORATION
    Inventors: Kouichi Ihata, Atsushi Umeda, Tsutomu Shiga
  • Publication number: 20070078627
    Abstract: A method and apparatus for designing a screw-tightening element are disclosed for designing the screw-tightening element (mechanical element). The design method comprises representing material characteristics of the screw component with factors including at least one of an elastic limit, an endurance strength, a true breaking power and a tension strength, representing a material characteristic of the tightening object with a factor including an elastic limit, providing a plurality of damage patterns associated with the material characteristics of the screw component and the tightening object, and calculating tolerance values of fluctuating loads in the plurality of damage patterns based on the material characteristics of the screw-tightening element and the elastic limit of the tightening object. The tolerance values of fluctuating loads are compared to determine an optimum tolerance load for the screw-tightening element.
    Type: Application
    Filed: September 28, 2006
    Publication date: April 5, 2007
    Applicant: DENSO CORPORATION
    Inventor: Tsutomu Shiga
  • Publication number: 20070044543
    Abstract: A method of designing a roller bearing is disclosed upon clarifying mechanisms of damage patterns in respect of two kinds of brinelling, involved in the bearing, wherein white-banded flaking (brittle flaking) is a plastic instability phenomenon appearing under high-speed deformation accompanied by adiabatic shear deformation status with the resultant occurrence of adiabatic shear band (also called white band) inside material of the bearing. This enables all of the damage patterns to be determined upon making comparison between shear strain and shear strain rate, occurring inside the bearing, and discriminated values.
    Type: Application
    Filed: July 26, 2006
    Publication date: March 1, 2007
    Applicant: DENSO CORPORATION
    Inventors: Atsushi Umeda, Tsutomu Shiga, Kouichi Ihata
  • Publication number: 20070024248
    Abstract: A method of calculating torque of a Lundell-type synchronous generator is disclosed in which only power generation output current and a rotational speed are input for calculation of the amount of electric power and the amount of losses for thereby enabling calculation of power generating torque, based on a sum of the amount of electric power and the amount of losses, which is generated as an output. The present method establishes formulae enabling calculation based on only output current and the rotational speed, enabling a minimal number of inputs to shorten a calculation time interval.
    Type: Application
    Filed: July 28, 2006
    Publication date: February 1, 2007
    Applicant: DENSO CORPORATION
    Inventors: Atsushi Umeda, Tsutomu Shiga, Kouichi Ihata
  • Patent number: 7165468
    Abstract: An outer diameter portion of a sealing member is rotatably supported by an inner surface of a nose portion. The axial movement of the sealing member is regulated. A tooth profile-shaped hole having approximately the same shape as that of a gear portion of a pinion is formed in the center of the sealing member. The gear portion of the pinion is constantly fitted into the tooth profile-shaped hole between the position where the pinion is stationary and the maximum moving position of the pinion in an axial direction. Therefore, the gear portion of the pinion cooperatively rotates with the pinion while sliding inside the tooth profile-shaped hole in the sealing member when the pinion moves on an output shaft in the direction opposite to the motor. Even after the gear portion mates with the ring gear, the sealing member cooperatively rotates with the pinion.
    Type: Grant
    Filed: January 8, 2004
    Date of Patent: January 23, 2007
    Assignee: Denso Corporation
    Inventors: Takashi Hirabayashi, Tsutomu Shiga
  • Publication number: 20060279151
    Abstract: An on-vehicle alternator is disclosed having a rotor driven by an engine via a belt, a stator having armature windings to generate electromotive forces in response to rotating magnetic fluxes, a housing on which the stator is fixedly secured, a pulley fixedly supported on the rotor to transmit a belt drive force to the rotor, and bearings rotatably supporting the rotor and fixedly supported on the housing. The power generator also includes a bush, formed of a metallic member, which is accommodated in the housing. The bearing, disposed in an area closer to the pulley, is comprised of an inner race, an outer race and rolling elements, all of which are formed of metallic members, with the outer race being press fitted to the bush with a certain degree of interference.
    Type: Application
    Filed: June 13, 2006
    Publication date: December 14, 2006
    Applicant: DENSO CORPORATION
    Inventors: Nakato Murata, Atsushi Umeda, Tsutomu Shiga
  • Publication number: 20060233478
    Abstract: A rolling bearing is adapted for an auxiliary device driven by an internal combustion engine via a belt. The rolling bearing comprises an inner race, an outer race, and a plurality of rolling elements disposed between the inner race and the outer race for rolling capabilities. A substantially half of a tolerance value of a clearance in a radial direction of the rolling bearing falls in a negative value, under a condition where the rolling bearing is mounted in the auxiliary device.
    Type: Application
    Filed: April 17, 2006
    Publication date: October 19, 2006
    Applicant: Denso Corporation
    Inventors: Atsushi Umeda, Tsutomu Shiga, Kouichi Ihata
  • Publication number: 20060223662
    Abstract: In an on-vehicle alternator using a serpentine drive system with a poly-V belt, a damping ratio of the alternator is rendered 0.5 or more as other auxiliary machines by considering six contributors to the damping ratio (i.e., pulley radii, a belt span, a moment of inertia, the number of belt ribs, an elasticity modulus of a single-body belt, and a hysteresis loss of a single-body belt). In one example, a pulley ratio of the alternator relative to an engine crankshaft pulley is rendered 2 or less. In another example, belt span lengths on both sides of the alternator are reduced by fixing the alternator to an on-vehicle engine using a side mounting system. The damping ratio of the alternator is thus increased to 0.5 or more, leading to a significant reduction in vibration in the serpentine drive system fixed to the on-vehicle engine.
    Type: Application
    Filed: March 30, 2006
    Publication date: October 5, 2006
    Applicant: DENSO CORPORATION
    Inventors: Kouichi Ihata, Tsutomu Shiga, Atsushi Umeda
  • Publication number: 20060210207
    Abstract: According to the present invention, a rolling bearing for supporting a rotary shaft of an automotive accessory includes an inner ring, an outer ring, a plurality of rolling elements interposed between the inner and outer rings, and grease. The grease has a withstand pressure greater than a predetermined range in which plastic deformation of at least one of surfaces of the inner and outer rings and rolling elements occurs in absence of an elastohydrodynamic lubrication film of the grease on the surface. With such a configuration, it is possible to reliably avoid plastic deformation of the inner and outer rings and rolling elements regardless of presence of elastohydrodynamic lubrication films between the inner and outer rings and the rolling elements. As a result, brittle flaking is reliably prevented from occurring in the rolling bearing.
    Type: Application
    Filed: March 6, 2006
    Publication date: September 21, 2006
    Applicant: Denso Corporation
    Inventors: Atsushi Umeda, Tsutomu Shiga, Kouichi Ihata