Abstract: A steer-by-wire steering apparatus for a vehicle has a first control system including a first ECU, and a second control system including a second ECU. Each ECU responds to manipulation of the steering wheel by a driver, and controls a steering motor. The first ECU determines whether the second control system is malfunctioning, and the second ECU determines whether the first system is malfunctioning. When any of the system is malfunctioning, the ECU of normally functioning system controls a counter force motor such that steering wheel receives a counter force that is different from that when both systems are functioning normally. Accordingly, the steering apparatus is capable of speedily and reliably causing a driver to realize a malfunction in the steering apparatus.
Abstract: In a hydraulic pump, a cam ring is provided in a cylindrical adaptor for movement in a radial direction, and a differential pressure control valve is provided to control internal pressure and load pressure at the front and back sides of a variable orifice to be introduced into action chambers and formed at the opposite sides of the cam ring for controlling a discharge amount of the pump in accordance with the rotation speed of the pump. The differential pressure control valve is operated under the internal pressure and load pressure respectively introduced into action chambers and the load of a thrust spring biasing the differential pressure control valve toward the internal pressure chamber. The load of the thrust spring is increased or decreased in accordance with an increase or a decrease of the load pressure.
Abstract: An electric power steering apparatus includes a booster circuit and a microcomputer. The booster circuit includes a booster coil, a first FET, and a second FET. The booster coil is connected to the first FET, which is grounded. A node a between the booster coil and the first FET is connected to the second FET, which is connected to a drive circuit. The microcomputer drives the first and second FETs such that the first and second FETs are selectively turned on and off, thereby controlling an output voltage of the booster circuit. When application of assisting force to a steering system is stopped, the microcomputer holds the second FETs on until the output voltage of the booster circuit becomes equal to a predetermined voltage.
Abstract: The contact angle of the ball 15 with each first guide track 21 of an inner joint member 12 is made to become smaller gradually from an opening portion side toward a bottom portion side, and the curvature radius for the first guide track 21 is made to become larger gradually from the opening portion side toward the bottom portion side. If the contact angle only were made to become smaller gradually from the opening portion side toward the bottom portion side, the contact angle would become too small thereby to cause chattering in rotation to be generated. If the curvature radius only were made to become larger gradually from the opening portion side toward the bottom portion side, a contact ellipse M2 defined by the ball 15 and the first guide track 21 would become tool small, which would cause the ball 15 to make dents on the surface of the first guide track 21.
Abstract: A microcomputer includes a rotation angular velocity computation section, a feedback gain determination section, and a dead time compensation amount determination section. The rotation angular velocity determination section computes the rotation angular velocity of a brushless motor. Based on the rotation angular velocity, the feedback gain determination section determines feedback gains. The dead time compensation amount determination section determines a dead time compensation amount. The greater the absolute value of the rotation angular velocity, that is, the higher the rotation speed of the brushless motor, the greater the feedback gains determined by the feedback gain determination section become, and the higher the responsivity of the feedback gains becomes. The greater the absolute value of the rotation angular velocity, the smaller the dead time compensation amount determined by the dead time compensation amount determination section becomes.
Abstract: A flow controlling apparatus for a power steering system includes a variable throttle mechanism installed in the pump to change the flow rate of discharged oil from the pump to a hydraulic device; a linear solenoid mechanism controlling the variable throttle mechanism by a predetermined energizing current; a spool feeding back the excess discharged oil to a bypass passage of the pump in accordance with a differential pressure between the upstream and downstream sides of the variable throttle mechanism when the excess fluid exceeds a predetermined value; and an ECU controlling the energized current to change the transition process in accordance with a steering angular velocity of the steering wheel.
Abstract: The invention provides an electric power steering apparatus which can detect a ground fault of an angular resolver without fault. Values of a first resistance (R1), a second resistance (R2), a third resistance (R3) and a fourth resistance (R4) are set such that a difference between a minimum output potential (Vout Min) of a first differential amplifier (OP1) at a time when an angular resolver is not in a ground fault which may be generated on the basis of a dispersion of the first resistance (R1), the second resistance (R2), the third resistance (R3) and the fourth resistance (R4), and a direct-current resistance component (Rdc) of the angular resolver, and a maximum potential (Vout Max) at a time when the angular resolver is in the ground fault becomes equal to or more than a predetermined margin for preventing an erroneous ground fault detection in a CPU (62) side.
Abstract: A transfer ratio varying apparatus includes: a steering shaft configured to transmit a steering angle, an actuator connected to the steering shaft and a damper disposed between the input shaft and the steering shaft and configured to absorb vibration caused by the actuator. The actuator includes: a housing, an input shaft configured to integrally rotate with the housing and connected to the steering shaft, a motor including a rotatable shaft, an output shaft configured to transmit an angle to a wheel assembly, and a gear mechanism between the rotatable shaft and the output shaft at the housing, configured to adjust a rotational angle of the rotatable shaft and to output the adjusted rotational angle to the output shaft.
Abstract: In a workpiece grinding method, a grinding allowance of a predetermined width (T) at at least an end surface portion 21 of a workpiece W is removed with a grinding wheel 10 (or 32) by rotating the workpiece W having a cylindrical portion 20 and the end surface portion 21 perpendicular thereto, by rotating the grinding wheel 10 (or 32) supported rotatably about an axis extending in parallel with the axis of the workpiece 10 (or 32), and by moving the grinding wheel 10 (or 32) relatively to the workpiece W.
October 7, 2005
Date of Patent:
October 10, 2006
Toyoda Koki Kabushiki Kaisha
Nobumitsu Hori, Kazuo Tabuchi, Mamoru Katsuta, Yoichi Ito
Abstract: In a grinding machine, a generally cylindrical workpiece having at least first and second grinding areas is ground by use of a grinding wheel supported by a wheel head. The first grinding area is first ground such that power consumed by the grinding machine is maintained at a first level. After completion of grinding for the first grinding area, the grinding wheel is indexed to the second grinding area by moving the wheel head such that the power consumed by the grinding machine is maintained at a second level higher than the first level. After completion of the indexing operation, the second grinding area is ground in the same manner as the first grinding area.
Abstract: An adhesion structure of a motor that adheres a rotor having a first linear expansion coefficient and a magnet having a second linear expansion coefficient, which differs from the first linear expansion coefficient, with an adhesive agent. The adhesion structure includes a thickness determining groove extending parallel to the axis of the rotor and arranged on the rotor in order to determine the thickness of an adhesive agent layer, which is formed from the adhesive agent. The thickness determining groove absorbs shearing stress produced by the difference between the first and second linear expansion coefficients at a surface adhered to the magnet. This effectively suppresses exfoliation of the adhesive agent layer.
Abstract: A driving force-transmitting device 10 has a housing 11 and 12, an inner shaft 18, a main clutch 22, a pilot clutch 24 and a cam mechanism 23 including a first and second cam members 26 and 25. Plural main outer and inner clutch disks 20 and 21 of the main clutch 22 are respectively spline-engaged with the housing 11 and the inner shaft 18. Plural pilot outer and inner clutch disks 32 and 33 of the pilot clutch 24 are respectively spline-engaged with the housing 11 and the first cam member 26 of the cam mechanism 23. The second cam member 25 of the cam mechanism 23 is arranged to constantly contact one of the main inner clutch disks 21 and is not spline-engaged with spline grooves of the inner shaft 18.
Abstract: A method of assembling a torque sensor includes the steps of fixing a first inner coil portion at one end side of a torsion bar, fixing a second inner coil portion at an other end side of the torsion bar, measuring an angle difference between an angle of the first inner coil portion and an angle of the second inner coil portion, fixing a first outer coil portion and a second outer coil portion, of which angle difference is substantially equivalent to the measured angle difference between the first inner coil portion and the second inner coil portion, at a housing, and rotatably disposing the torsion bar fixed with the first inner coil portion and the second inner coil portion in the housing.
Abstract: A machine tool includes X-axis, Y-axis, and Z-axis moving units for producing relative movements between a tool and a workpiece; a C-axis drive unit for rotating the workpiece about a C-axis parallel to the Z-axis; and a B-axis turning unit for turning the tool about a B-axis parallel to the Y-axis. The tool is disposed in such a manner that a machining point of the tool coincides with the B-axis. The moving units, the drive unit, and the turning unit are controlled in such a manner that a work point of the workpiece coincides with the machining point of the tool. The bed is formed through casting and has a hollow structure and a hole as cast; and a cover is provided to cover the hole as cast in order to close the interior of the bed.
Abstract: Disclosed is a cylindrical grinding machine of the type that a workpiece support device composed of a work head and a foot stock is mounted on a forward upper portion of a bed while a wheel head unit composed of a slide base and a wheel head is mounted on a rear upper portion of the bed. A coolant collecting vent which takes a rectangular shape as viewed from above vertically extends in the bed and opens to the upper surface of the bed to cover an area that extends from under the workpiece on the workpiece support device to under the forward portion of the wheel head unit. A horizontal vent is provided in the bed to open to the rear surface of the bed and to communicate with the collecting vent. A coolant supply device is inserted at a part thereof into the horizontal vent from the rear surface of the bed to extend an inlet opening into the collecting vent.
Abstract: A microcomputer includes an actual DUTY value detection section that detects an actual DUTY value ?x by measuring the ratio of time in which an output voltage of each phase becomes a power supply voltage in a cycle of a triangular wave. A dead time compensation computation section subtracts the actual DUTY value ?x from a DUTY instruction value ?x before correction, thereby computing a difference value ?x. Subsequently, the dead time compensation computation section adds the difference value ?x to dead time compensation amounts ?xp, ?xm, which have been used for correcting the DUTY instruction value ?x, thereby determining new dead time compensation amounts ?xp? and ?xm?. The dead time compensation amounts ?xp, ?xm stored in a memory are renewed with the new dead time compensation amounts ?xp?, ?xm?.
Abstract: A motor control apparatus includes a direct-current power source and an inverter circuit, which includes a switching element. The motor control apparatus receives a current command value in every control cycle and calculates a current deviation accumulated value by accumulating the current deviation between the received current command value and the actual current value that flows through a coil of a motor. The motor control apparatus then computes a voltage command value in accordance with the current deviation accumulated value and controls the switching timing of the switching element based on the voltage command value. The motor control apparatus judges whether the computed voltage command value exceeds a range of the voltage that can be output from the inverter circuit and causes saturation. If it is judged that the voltage command value is saturated, the motor control apparatus restricts the accumulation of the current deviation.
Abstract: A production equipment monitoring device comprises a display panel providing a touch switch function, a touch switch display controller displaying on the display panel a touch switch corresponding to a general segmentary operating process, an operating status display controller distinguishably displaying thereon an operating status of the touch switch corresponding to the general segmentary operating process presently executed, a detail process information memory memorizing a name of a detail operating process and an address of the programmable logic controller to be referred thereto when judging an actual status of the detail operating process, and a detail information display controller displaying thereon, when the touch switch is pressed, the name of the detail operating process included in the general segmentary operating process corresponding to the pressed touch switch, and the actual status of the detail operating process obtained by the address of the programmable logic controller.
Abstract: A pressure sensor is provided with a semiconductor device that is capable of detecting a pressure, a terminal that is connected to the semiconductor device by a bonding wire, a housing having an accommodation space for the semiconductor device, the bonding wire, and the terminal, a diaphragm for sealing the accommodation space, and working fluid that is sealed in the accommodation space and transmits a pressure applied to the diaphragm to the semiconductor device. The working fluid is silicone-based oil, and the terminal and the housing are sealed by fluorine-based adhesive.
Abstract: An internal gear 10 is rotatably received within a housing 8 (planetary carrier 2 and case 4), and a sun gear 12 is rotatably disposed on a circle located inside of and concentric with the internal gear 10. Planet gears 14 which are carried within carrying openings 2c formed in a planetary carrier 2 are disposed between the internal gear 10 and the sun gear 12 in meshing engagement with the internal gear 10 and the sun gear 12. The internal gear 10, the sun gear 12 and the planet gears 14 each have spherical gear teeth, and develops a thrust upon occurrence of a relative rotation therebetween. A coupling 16 is connected to the inner periphery of the internal gear 10 through helical splines 10d and 16a for purpose of power transmission. The helical splines provide a novel thrust generating mechanism, which enlarges the extent in which a bias ratio can be adjusted.