Abstract: The atmosphere temperature calculator calculates an estimated atmosphere temperature value by subtracting a temperature rise amount of a temperature sensor which is calculated based on a motor drive detected current value from a detected temperature value of the temperature sensor. The overheating prevention calculator calculates estimated temperature values of a plurality of protection objects to be protected from overheating based on the estimated atmosphere temperature value and the motor drive detected current value and determines an upper limit of target current of driving a motor based on such estimated temperature values. The temperature compensation calculator calculates a temperature compensation current value to be added to a target current value in order to compensate a temperature characteristic of a predetermined portion based on the estimated atmosphere temperature value.
Abstract: It is one object of a hale-machining method and apparatus thereof according to the present invention to achieve an easy preparation of an NC machining program and perform a high geometrical accuracy in the predetermined three-dimensional free curved surface. A haling tool 34 is set on a tool holder 32 in such a manner that a cutting point P of the haling tool 34 is substantially coincided with an intersection of a first rotating axis B, a second rotating axis A and a third rotating axis C. A rotary table 16 and a rotary base 24 are rotated in such a manner that a tool axis direction of said haling tool is substantially coincided with a normal direction of said machined surface. A tool holder 32 is rotated in such a manner that a front rake surface of the haling tool 34 is substantially directed in perpendicular to a feeding direction of said haling tool 34.
Abstract: In a torque sensor, a first detection tube (13) made from magnetic material covers a cylindrical magnetic leak prevention member (12) that is made from nonmagnetic material and covers a first shaft (3) made from magnetic material. Magnetic resistance to magnetic flux, which passes through one end of the first detection tube (13) and one end of a second detection tube (14) that is made from magnetic material and rotates together with a second shaft (4), changes according to elastic relative rotation of the two shafts (3, 4) corresponding to transmitted torque, by providing a plurality of teeth (13a, 14a) along the circumferential direction at the one end of each detection tube (13, 14). The first shaft (3) and the first detection tube (13) are integrated with the magnetic leak prevention member (12) so that they can rotate together, by being inserted in a mold for forming the magnetic leak prevention member (12) before the synthetic resin material is poured into the mold.
Abstract: The invention provides an electric power steering apparatus in which a dead zone is not generated even at a low duty ratio while slow starting a switching element. When a duty ratio of a PWM control becomes more than a preset value (NO in S14), a switching cycle is set to a predetermined value (a fixed value) (S20). When the duty ratio becomes equal to or less than the preset value (Yes in S14), the switching cycle is made longer than the predetermined value (S16). It is possible to securely apply a current to a motor and it is possible to prevent a dead zone from being generated, by elongating the switching cycle even in a low duty ratio while slow starting an FET and preventing a noise from being generated.
Abstract: A pair of hydrostatic radial bearing devices 42, 43 is mounted on right and left side surface of a front portion of a wheel slide 34 in order to support rotatably wheel shafts 45, 52 respectively. A thrust bearing device 45 mounted in either one of wheel shafts 45, 52 supports either wheel shaft 45 or 52 in a thrust direction. A shaft coupling mechanism 60 is installed in wheel shafts 45, 52. A taper cylindrical portion 61 is projected from either one of wheel shafts 45, 52 and fitted tightly with a taper inside opening 65 formed in remaining of wheel shafts 45, 52. A vertical end surface 52t, 49t or Fb extending from a base of the taper cylindrical portion 61 is fitted tightly with another vertical end surface 45t, 52t or 45t of the remaining wheel shaft 45 or 52.
Abstract: Disclosed are a combination of a drive power transmission device and a differential gear, which combination is decreased in the number of parts, increased in rigidity and reduced in weight as well as in manufacturing cost, and a method of manufacturing the combination. A gear shaft which is provided with a drive gear for a differential gear is rotatably supported in a differential case. The differential case is provided with a partition wall portion which extends outwardly from an opening end portion thereof from which the gear shaft protrudes. A clutch case is secured to the circumferential edge portion of the partition wall portion thereby to define a housing chamber. A housing with a clutch receiving chamber formed therein is rotatably supported on the clutch case inside the housing chamber.
Abstract: A curved leaf spring which is a first urging member surrounds an outer wheel of a second bearing, and urges, through the second bearing, a second end of a worm shaft in a direction in which the distance between the center of the worm shaft and the center of a worm wheel is shortened. A second urging member includes an annular support member received by an end surface of the outer wheel and a plurality of elastic pins extending in a direction in parallel with the axial direction of a support member. The elastic pins have fixed ends fixed to the support member and free ends that come into elastic contact with an end wall of a housing.
Abstract: A control box 10 according to the present invention has at least one electric device 12 and fan unit 17 inside a case 11. In the case 11, a dividing board 15 divides a room into two rooms which include a heated room 30, close to the electric device 12, and a ventilated room 31. First and second openings 24B,24A open the heated and Ventilated rooms 30,31 to the outside of the case 11, respectively. The fan unit 17 is disposed on a window penetrating the dividing board 15 and feeds air from one of two rooms to another.
Abstract: A controller for a brushless motor that suppresses torque reduction resulting from the influence of motor inductance and suppresses the generation of invalid current. A phase advancing angle calculator calculates a delay angle of phases of phase currents with respect to the phases of the phase voltage command and a phase advancing angle corresponding to the delay angle based on the function of the angular velocity and the motor inductance (and armature winding resistance) of the brushless motor. An adder adds the phase advancing angle to the rotation angle provided from the rotation angle calculator to generate the corrected rotation angle. The adder further provides the corrected rotation angle to a two-phase/three-phase converter.
Abstract: An angle detection apparatus includes a resolver having a rotor core and a stator core, and a computation unit having a multiple rotation amount computation, accumulation and an abnormality determination sections. The rotor core moves along the axial direction of a steering shaft in response to rotation of the steering shaft. Based on a change of a transformation ratio of the resolver caused by a change of the relative positions of the rotor core and the stator core along the axial direction due to movement of the rotor core, the multiple rotation amount computation section computes a first multiple rotation amount N of the steering shaft. The multiple rotation amount accumulation section detects the switchover point of the absolute angle .theta.0 when the steering shaft is rotated a single rotation, and computes a second multiple rotation amount N? by accumulating the number of detection of the switchover point.
Abstract: An electric power steering apparatus includes a first resolver whose pole pair number is ‘m’ and a second resolver whose pole pair ‘n’. The electric power steering apparatus further includes a torsion calculating means which calculates the a torsion angle of the torsion bar from a difference between the rotating angle detected by the first resolver and the rotating angle detected by the second resolver. The torsion calculating means compensates the angle difference by a compensation value obtained by a table on the basis of the value obtained by multiplying an electrical angle of the first resolver by ‘n’ and the value obtained by multiplying an electrical angle of the second resolver by ‘m’.
Abstract: An electromagnetic clutch includes a first magnetic member with a large-diameter cylindrical portion made of a magnetic metal and a second magnetic member with a small-diameter cylindrical portion made of a magnetic metal and contained in the large-diameter cylindrical portion are joined to an annular member of a non-magnetic material interposed between the large and small-diameter cylindrical portions to constitute a magnetic path forming member. The outer and inner circumferential edges of the annular member are welded to the large-diameter cylindrical portion and the small-diameter cylindrical portion, with the front end surface of the annular member receding a second predetermined distance (L2) from the front end surfaces of the large and small-diameter cylindrical portions. Then, the front end surfaces of the large and small-diameter cylindrical portions are cut until the receded distance of the front end surface of the annular member becomes a first predetermined distance (L1).
May 18, 2004
Date of Patent:
July 4, 2006
Toyoda Koki Kabushiki Kaisha
Kunihiko Suzuki, Hirokazu Harada, Koji Kamiya
Abstract: In an oil pump apparatus, a drain outlet is positioned outwardly from an inner peripheral surface of a suction passage or from an extended line thereof at a sectional view which takes along an orthogonal direction relative to a central axis of the suction passage and which shows the drain outlet, and/or the drain outlet is positioned at a side of a shaft aperture to be away from an imaginary line connecting a central axis of a discharged passage and a central axis of the suction passage at a sectional view which takes in parallel with the central axis of suction passage and which shows the drain outlet, such that the opening center of the drain outlet is not overlapped on the imaginary line.
Abstract: When a variable value indicates that a steering characteristic is understeer, a control unit controls a variable transmission ratio device to change a second steering angle such that the greater the understeer indicated by the variable value, the smaller the steering angle of steered wheels relative to the turning angle of a steering wheel becomes. When the differentiated value of the variable value indicates that the understeer is changing to increase, a correction unit corrects the variable value such that the greater the degree of change of the understeer indicated by the differentiated value, the greater the understeer indicated by the variable value becomes. Hence, the attitude of a vehicle in understeer is stabilized with a simple configuration.
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: In a cylindrical grinding machine for grinding a rotating cylindrical workpiece with a rotating grinding wheel, a wheel spindle for supporting the grinding wheel is divided at its axial mid portion into first and second spindle components, and respective ends on the sides opposite to the axial mid portion of the first and second spindle components are rotatably supported by a pair of fluid bearings. Each of the first and second spindle components has at least at its portion supported by a corresponding one of the fluid bearings a diameter which is determined to secure a predetermined rigidity at a grinding point between the grinding wheel and the workpiece, based on a predetermined value obtained taking into consideration the power consumption by the fluid bearings or the quantity of energy consumption required from the beginning to the ending of a grinding operation. Thus, the grinding machine can be reduced in the energy consumed from the beginning to the ending of the grinding operation.
Abstract: A torque sensor is provided with a torsion bar, first and second elongate sleeves respectively secured to one and the other ends of the torsion bar, and a pair of resolvers respectively mounted on the first and second elongate sleeves. First and second stop portions are provided respectively at overlapping portions of the first and second elongate sleeves where the second elongate sleeve is fit partly on the external surface of the first elongate sleeve with a play. A rotary sleeve given to one of the resolvers is press-fit on the external surface of the stop portion provided on the second elongate sleeve for mounting one of the resolvers thereon as well as for reinforcing the mechanical strength of the stop portion provided on the second elongate sleeve. Further, the resolvers used therein are chosen as those respectively having n-poles and m-poles.
Abstract: A grinding method of a crank pin that grinds an outer circumferential surface of the crank pin of a crankshaft having a crank journal and the crank pin eccentric to the crank journal by rotating a crankshaft around a central axis (a center of the journal) of the crank journal and moving a rotating grinding wheel in a diametric direction of the crankshaft according to rotation phase angle of the crankshaft, in which a rotation number of the crankshaft is changed in one revolution of the crankshaft to perform a grinding process.
December 2, 2005
June 8, 2006
TOYODA KOKI KABUSHIKI KAISHA
Nobumitsu Hori, Makoto Nonoyama, Kikutoshi Okada
Abstract: In accordance with a vehicle motion control apparatus, a steering angle (?h) of a steering wheel is determined on the basis of a rotation angle (?pm) of an assist motor (24m) detected by a rotation angle sensor (24s) and a rotation angle (?vm) of a gear ratio variable motor (32m) detected by a rotation angle sensor (32s), and a VGRS control process (40a) of a gear ratio variable mechanism is executed on the basis of the determined steering angle (?h). Accordingly, since the steering angle (?h) of the steering wheel is determined on the basis of the rotation angle (?vm) used for the VGRS control process (40a) of the gear ratio variable mechanism and the rotation angle (?pm) used for an EPS control process (30a) of an EPS actuator, it is possible to obtain the steering angle (?h) of the steering wheel without a steering angle sensor. Therefore, it is possible to reduce the number of the parts of a vehicle motion control apparatus.
Abstract: A constant velocity universal unit includes an outer joint member whose inner peripheral face is formed with three guide grooves, an inner joint member including three tripod shafts each formed with a tripod spherical face, three roller units each including an outer peripheral face and an inner peripheral face coaxially formed with each other. The guide groove includes a pair of strip-shaped inner side faces formed with a pair of guide projections having a substantially half arc shape in cross section whose diameter is smaller than a height of the inner side face of the guide groove. The constant velocity universal joint further includes an annular recess formed on a substantially center portion in a height direction of the outer peripheral face of the roller unit and engaging with the pair of guide projections in a rolling manner and rotatable relative to a central axis of the guide projection.