Patents Assigned to JTEKT
-
Patent number: 8934211Abstract: A solenoid control device executes feedback control such that a drive current for a solenoid follows a target current, by driving, through PWM, a MOSFET provided on a power supply line to the solenoid. An overcurrent detection circuit that outputs an overcurrent detection signal when the drive current for the solenoid reaches an overcurrent determination current value is provided, and it is determined whether an overcurrent is generated. Whether a short-circuit occurs between both terminals of the solenoid is determined by monitoring whether the overcurrent detection circuit is repeating an output of the overcurrent detection signal and a stop of the output of the overcurrent detection signal.Type: GrantFiled: February 26, 2013Date of Patent: January 13, 2015Assignee: JTEKT CorporationInventors: Atsushi Takeshita, Hisaaki Wakao, Kiyoshige Kato, Kazuhiro Murakami
-
Publication number: 20150010408Abstract: A control unit includes an excessive output suppression control unit which suppresses an excessive output by reducing a current command value from a host control apparatus. A control signal output unit obtains a motor control signal by adding a reduction amount of the current command value to the current command value. The excessive output suppression control unit includes: an oil pressure estimating unit which estimates oil pressure based on a current and a rotating speed of the electric motor; and a current command value correction amount calculating unit which compares outputs the reduction amount of the current command value if the estimated oil pressure is higher than target oil pressure. One of the target oil pressure and the estimated oil pressure compared by the current command value correction amount calculating unit is corrected based on oil temperature information.Type: ApplicationFiled: December 27, 2012Publication date: January 8, 2015Applicant: JTEKT CORPORATIONInventors: Hiroki Kagawa, Kengo Uda, Yasuyuki Aoki
-
Publication number: 20150012126Abstract: A thermal displacement correction method for a machine tool includes: estimating a thermal displacement of a support and a thermal displacement of the movable body independently of each other; acquiring a displacement of an attachment position of a scale that detects a position of the movable body; a movable body actual position acquiring step of acquiring an actual position of the movable body relative to the support after thermal deformation of the movable body; computing a degree of inclination of the movable body at the actual position; acquiring a resultant displacement that is a resultant of the thermal displacement of the support and the thermal displacement of the movable body; computing a correction value based on the resultant displacement; correcting a command position of the movable body based on the correction value.Type: ApplicationFiled: June 23, 2014Publication date: January 8, 2015Applicant: JTEKT CORPORATIONInventors: Yuji SASAKI, Hideki IWAI, Yasumasa SAKURAI
-
Patent number: 8925938Abstract: A vehicle steering system includes a steered shaft, and stoppers which restrict an amount of movement of the steered shaft in an axial direction. The steered shaft has first outer peripheral faces, second outer peripheral faces, and annular stepped portions. Each stepped portion includes a contact portion that faces a corresponding one of the stoppers in the axial direction, a first corner portion that has a concave curved sectional shape and connects the first outer peripheral face to an inner end of the contact portion, and a second corner portion that has a concave curved sectional shape with a larger curvature radius than that of the first corner portion, and connects the first outer peripheral face to the second outer peripheral face, at a position in front of or behind a central axis of the steered shaft.Type: GrantFiled: November 13, 2012Date of Patent: January 6, 2015Assignee: JTEKT CorporationInventor: Kosuke Yamanaka
-
Patent number: 8926885Abstract: A method of molding a boot for a constant velocity joint includes: molding a compact by injection molding; raising split dies of an inner die so as to separate the split dies from a set ring; raising a core shaft of the inner die so as to separate the core shaft from the split dies; separating each of the split dies from the compact; introducing a lower end portion of the separated split die into the set ring along an engaging surface; and inserting a lower end portion of the core shaft through the set ring from above the set ring, and pressing upper end portions of the split dies downward by a protruding portion at an upper end portion of the core shaft so that the lower end portions of the split dies are engaged with the engaging surface and the split dies are brought into close contact.Type: GrantFiled: November 18, 2013Date of Patent: January 6, 2015Assignee: JTEKT CorporationInventors: Hiroshi Ueno, Kazuki Hamada
-
Patent number: 8925673Abstract: A preload adjusting plug is inserted through a communication hole extending through center portions of a Z1 gear, a Z4 gear, and an inner ring of a nutation gear. A male thread portion is formed at an outer periphery of one end of the preload adjusting plug, and is screwed to a female thread portion formed at an inner periphery of the Z1 gear. A disc-shaped flange portion extending radially outward is formed at the other end of the preload adjusting plug, and axially presses a back face of the Z4 gear through a bearing. The preload adjusting plug applies predetermined preloads to meshing portions in the nutation gear mechanism.Type: GrantFiled: December 9, 2013Date of Patent: January 6, 2015Assignee: JTEKT CorporationInventor: Satoshi Motoyama
-
Patent number: 8930077Abstract: A damping control unit sets a damping torque command value that corresponds to a steering angular velocity when a direction of a detected steering torque is a turning direction, a magnitude of the detected steering torque is larger than or equal to a first threshold, a direction of the steering angular velocity is a returning direction and a magnitude of the steering angular velocity is higher than or equal to a second threshold. An addition unit adds the damping torque command value generated by the damping control unit to a basic assist torque command value set by a basic assist torque command value setting unit.Type: GrantFiled: November 16, 2012Date of Patent: January 6, 2015Assignee: JTEKT CorporationInventor: Masahiko Sakamaki
-
Patent number: 8925939Abstract: A steering system includes a rack shaft, a rack housing, a rack end, and an impact absorbing member that is provided between a restriction face formed within the rack housing and an end face of the rack end, and that absorbs an impact generated when the restriction face and the end face come into contact with each other. The impact absorbing member includes an elastic portion, and a restriction portion having an elastic modulus higher than that of the elastic portion and having a length in the axial direction, which is shorter than that of the elastic portion. A compression allowance, which is a difference in length in the axial direction between the elastic portion and the restriction portion, is brought to zero when the restriction face and the end face come into contact with each other via the impact absorbing member due to a steering input.Type: GrantFiled: November 7, 2013Date of Patent: January 6, 2015Assignee: JTEKT CorporationInventor: Tatsuya Ohashi
-
Publication number: 20150000135Abstract: A blank is provided with a first shaft portion, a second shaft portion, and a machining target portion. The machining target portion is formed at a position closer to a shaft end portion of the first shaft portion than a shaft end portion of the second shaft portion. A first large-volume portion is formed at the first end portion of the machining target portion close to the first shaft portion, and a second large-volume portion is formed at the second end portion of the machining target portion close to the second shaft portion, respectively. The volumes per unit length of the first and second large-volume portions are greater than the volume per unit length of the intermediate portion in the axial direction of the machining target portion. Furthermore, the volume of the second large-volume portion is greater than the overall volume of the first large-volume portion.Type: ApplicationFiled: June 9, 2014Publication date: January 1, 2015Applicant: JTEKT CORPORATIONInventor: Hiroyuki OUMI
-
Patent number: 8922145Abstract: Three-phase resolver signals that are output from a resolver upon reception of an excitation signal are captured by a microcomputer. The microcomputer computes a rotation angle of an electric motor on the basis of the three-phase resolver signals. The ratio between an excitation period of the excitation signal and a capturing period of each of the three-phase resolver signals is set to 8:5. A computation period of the rotation angle is set to half of the least common multiple of the excitation period of the excitation signal and the capturing period of each resolver signal.Type: GrantFiled: March 14, 2013Date of Patent: December 30, 2014Assignee: Jtekt CorporationInventor: Noritake Ura
-
Patent number: 8924172Abstract: A power consumption display unit for a machine tool includes: machining state determining means for determining, when a main power switch used to supply power to a machine tool is ON, whether the machine tool is in a machining state where a machining program is executed to machine a workpiece or in a non-machining state where the machining program is not executed; power consumption measuring means for measuring a power consumption of the machine tool during a period where the machine tool is determined to be in the non-machining state by the machining state determining means; and display means for displaying the power consumption measured by the power consumption measuring means.Type: GrantFiled: October 14, 2011Date of Patent: December 30, 2014Assignee: Jtekt CorporationInventors: Koji Hasegawa, Hirotaka Sugiura, Takeshi Kojima
-
Patent number: 8920211Abstract: A truing device of a grinding machine includes: a truer that corrects a shape of a grinding wheel; a swivel table that supports the truer such that the truer is swivelable about a swivel axis Ac; detecting means for directly detecting a distance from a truing edge position of the truer, which contacts the grinding wheel during correction of the shape of the grinding wheel, to a swivel center O of the swivel table; and control means for controlling the truing edge position of the truer with respect to the grinding wheel based on the distance L detected by the detecting means to true the grinding wheel.Type: GrantFiled: June 8, 2012Date of Patent: December 30, 2014Assignee: JTEKT CorporationInventors: Yoshio Wakazono, Tetsuro Furuhata, Hisanobu Kobayashi
-
Patent number: 8924038Abstract: The invention relates to a power steering system in which the set value for torque or force at the steering wheel is predetermined on the basis of various parameters and information so as to provide the most driving comfort in all conditions of driving the vehicle. The torque or force set value is predetermined on the basis of the sideways acceleration of the vehicle, the acceleration in turn being predetermined mainly from an estimate of the force exerted on the rack, and preferably also predetermined by other methods, with the estimate being weighted among all of the obtained values. Said method is particularly useful for vehicles provided with electrical power steering.Type: GrantFiled: July 20, 2010Date of Patent: December 30, 2014Assignee: JTekt EuropeInventors: Andre Michelis, Pierre Pilaz, Pascal Moulaire, Serge Gaudin
-
Patent number: 8915651Abstract: An inner ring member having multiple flange portions is formed by cold forging. A tapered surface is formed in a state of a forged surface on the inner ring member so as to gradually increase in diameter from an inner side toward an outer side in a vehicle lateral direction over a region from a position near root portions of inner side faces of the flange portions in the vehicle lateral direction to a position radially outward of an outer periphery of an outer end portion of an outer ring member in the vehicle lateral direction. A seal member is attached to the outer periphery of the outer end portion of the outer ring member. A seal lip that is in sliding contact with the tapered surface in the state of a forged surface is formed at a distal end portion of the seal member.Type: GrantFiled: January 14, 2013Date of Patent: December 23, 2014Assignee: Jtekt CorporationInventors: Yoshinori Masuda, Tatsuya Yokota
-
Patent number: 8911155Abstract: A cage bar of at least one of pockets, the cage bar being on one side of the at least one of the pockets in the circumferential direction, has a bent portion that is bent toward one side in an axial direction such that an end face of the cage bar on the other side in the axial direction is recessed toward the one side in the axial direction. Further, a cage bar of the at least one of the pockets, the cage bar being on the other side of the at least one of the pockets in the circumferential direction, has a bent portion that is bent toward the other side in the axial direction such that an end face of the cage bar on the one side in the axial direction is recessed toward the other side in the axial direction.Type: GrantFiled: October 31, 2013Date of Patent: December 16, 2014Assignee: JTEKT CorporationInventor: Takaaki Onizuka
-
Patent number: 8910731Abstract: In a material handling and stair climbing vehicle, when the vehicle is shifted from a state where the wheels with two axles are grounded on a travelling surface to a standing state achieved by the wheels with one axle, a main body portion is turned around support shafts with respect to supporting portions in the two-axle wheel grounded state. Then, an inertial force around the support shafts is generated by reducing the speed of turning of the main body portion with respect to the supporting portions. Then, the vehicle is shifted to the standing state achieved by the wheels with one axle by turning the supporting portions around the axles of the wheels with one axle, which are grounded on the travelling surface, by the inertial force.Type: GrantFiled: October 18, 2013Date of Patent: December 16, 2014Assignee: JTEKT CorporationInventors: Takeshi Ueda, Genki Murata
-
Patent number: 8910977Abstract: A steering device includes a steering column that rotatably supports a steering wheel, a column side bracket that supports the steering column, a vehicle body side bracket coupled to the column side bracket and an impact absorption mechanism that moves the steering column in a direction along the steering column in a second collision. The impact absorption mechanism includes an impact absorption member and a supporting member. The impact absorption member is integrally formed with an elastic supporting portion and an extending portion. The elastic supporting portion is supported by the vehicle body side bracket and elastically supports the steering column. The extending portion extends in a direction along the steering column. The supporting member is supported by a vehicle body and supports a part of the extending portion in a longitudinal direction of the extending portion.Type: GrantFiled: August 9, 2013Date of Patent: December 16, 2014Assignee: Jtekt CorporationInventor: Toru Sakata
-
Patent number: 8910366Abstract: The invention provides a press-fitting method of a member and a press-fitting apparatus in which press-fitting errors can be reduced, without using a dummy pin. The pressing jig 45 includes a main body 46 having a guide pin containing part 47 which is open downward, a compression coil spring (a resilient member) 48 which is contained in an upper part of the guide pin containing part 47, a guide pin 49 which is contained in a lower part of the guide pin containing part 47 with its lower end portion projected downward from a lower face of the main body 46 by an urging force of the compression coil spring 48, and a permanent magnet 50 in an annular shape which is fixed to the lower face of the main body 46, as attracting and holding unit for attracting and holding the press-fitting member 11.Type: GrantFiled: December 24, 2008Date of Patent: December 16, 2014Assignee: JTEKT CorporationInventor: Masaru Fuse
-
Publication number: 20140364242Abstract: A universal joint includes a pair of yokes and a joint cross. The pair of yokes have mutually identical shapes. Each of the yokes has a proximal portion and a pair of arm portions at which the joint cross is mounted. The proximal portion has an insertion hole for mounting a shaft, a slit formed along the insertion hole and a bolt insertion hole for fastening the slit. A positional relationship between the proximal portion and the pair of arm portions is set such that a line segment that connects the pair of arm portions to each other and an insertion direction in which a bolt is inserted in the bolt insertion hole intersect with each other at 45°. The bolt insertion holes of the pair of yokes coupled by the joint cross face the same side.Type: ApplicationFiled: February 8, 2013Publication date: December 11, 2014Applicant: JTEKT CORPORATIONInventors: Takeshi Koyama, Kohei Yamamoto
-
Publication number: 20140360745Abstract: A main spindle unit includes: a damper bearing that restricts vibrations of a main spindle by being supplied with a fluid; a fluid supply device that supplies the fluid to the damper bearing, and that is able to adjust a flow rate of the fluid; a vibration detection sensor that detects a vibration of the main spindle; and a controller that adjusts the flow rate of the fluid supplied from the fluid supply device, based on the magnitude of the vibration detected by the vibration detection sensor.Type: ApplicationFiled: June 4, 2014Publication date: December 11, 2014Applicant: JTEKT CORPORATIONInventors: Shigeru MATSUNAGA, Ryota Tanase