Abstract: A roller bearing cage includes annular portions provided respectively at opposite ends thereof, a plurality of pillar portions interconnecting the annular portions, a plurality of pockets for respectively holding needle rollers, and roller retaining portions formed respectively on circumferentially-opposed wall surfaces and of each pocket portion. A concave groove smaller in width than the pillar portion is formed axially in a back surface of each pillar portion and those portion of back surfaces of the annular portions disposed respectively at opposite ends of each pillar portion. Separation groove portions are formed respectively at opposite sides of those portions of the concave groove disposed respectively at the opposite ends of the pillar portion, and extend respectively to corresponding circumferentially-opposite side surfaces of the pillar portion, and each separation groove portion separates the corresponding roller retaining portion and annular portion from each other.

Abstract: An inner ring is fitted on one-end side of an inner shaft and fixed to the inner shaft by caulking. During the caulking, the inner shaft is supported by a caulking receiving jig. A receiving section to which the jig is in contact is provided at a position near the one-end side of the inner shaft, for example, at a position nearer to the inner ring than a raceway section formed on the outer periphery on the other side of the inner shaft. As a result, a caulking load acting from a caulking jig on the inner shaft plastically deforms only a desired portion.

Abstract: An oil supply unit provided in a rolling bearing apparatus has a lubricating oil discharge nozzle in which an opening is faced to a cage portion of the rolling bearing. An opening direction of the nozzle is inclined to a rotating direction with respect to a direction of a center axis of rotation.

Abstract: A vehicle steering system including a transmission ratio variable mechanism that has a first shaft connected to a steering member and a second shaft connected to a turning mechanism, coupled coaxially to each other, and a transmission ratio variable mechanism motor disposed coaxially with the first and second shafts for driving the transmission ratio variable mechanism. The transmission ratio variable mechanism motor includes a tubular rotor, and an accommodation space is defined on the inner side in the radial direction of the tubular rotor. At least one of sensors is disposed inside the accommodation space.

Abstract: It is an object of the present invention to provide a controller for a machine tool and a five axis simultaneous control machine tool controlled thereby which can improve machining accuracy in controlling a pivoting axis of the machine tool. The controller comprises an allowable position error setting member 101 setting an allowable position error ? between a commanded machining position P1 and an actual machining position P2, a velocity control parameter deciding member 103 deciding a velocity control parameter of the pivoting axes of the A-axis and the B-axis in accordance with the allowable position error ? being set and a distance of said actual machining position P2 from the pivoting axes of the A-axis and the B-axis, and a controlling member 104 controlling a velocity of the pivoting axes of the A-axis and the B-axis based on the velocity control parameter.

Abstract: An upper surface of an outer ring is disposed axially inwardly of an end surface of a larger-diameter annular portion of a cage, and an outer diameter of the end surface of the larger-diameter annular portion of the cage is larger than an inner diameter of a lower surface of the outer ring. Chamfered portions for facilitating the taking-out of an outer ring assembly from the lower side of a stack of outer ring assemblies are formed respectively at the end surface of the larger-diameter annular portion of the cage and the lower surface of the outer ring.

Abstract: The clearance between the outer peripheral surface of an annular portion of a cage and the inner peripheral surface of each of rib portions of outer-ring split pieces is set to be smaller than the clearance between the radial end surface of a projection portion of the cage and the inner peripheral surface of each of body portions of the outer-ring split pieces. When a centrifugal force due to engine rotation acts upon the cage, the inner peripheral surface of each of the rib portions of the outer-ring split pieces touches the outer peripheral surface of the annular portion of the cage before the inner peripheral surface of each of the body portions of the outer-ring split pieces touches the radial end surface of the projection portion of the cage. Thus, the radial displacement of the cage can be prevented in good time.

Abstract: An electric power steering apparatus includes a driving target value setting unit for setting a driving target value of an electric motor; a steering acceleration detecting unit for detecting or estimating a steering acceleration; a correction amount computing unit for computing a control correction amount in accordance with the steering acceleration; a vehicle acceleration detecting unit for detecting an acceleration of a motor vehicle; an acceleration adaptive gain setting unit for setting a gain in accordance with an acceleration of a motor vehicle; a multiplication unit for determining a gain adjusted control correction amount by multiplying the control correction amount with the acceleration adaptive gain; a correcting unit for correcting the driving target value on the basis of the gain adjusted control correction amount; and motor driving units for driving the electric motor on the basis of the corrected driving target value.

Abstract: An electromagnetic pilot opening/closing valve includes: a valve main body member that includes a sliding hole; a main valve body that is slidably provided in the sliding hole; a movable iron core; and a fixed iron core. The main valve body includes a second sliding hole. A pilot valve body is provided in the second sliding hole. The movable iron core and the pilot valve body are designed to slidably engage with each other, and the movable iron core and the main valve body are designed to slidably engage with each other with a play therebetween. When the movable iron core is attracted by the fixed iron core by energization of the coil, the movable iron core causes the pilot valve body to slide inside the second sliding hole and sliding of the pilot valve body causes the main valve body to slide inside the sliding hole.

Abstract: An angle calculator determines an angle of a rotor. An angular speed calculator determines an angular speed of the rotor. A command current calculator determines a command current defined on a dq-axis. An open loop controller determines a command voltage defined on the dq-axis in accordance with a circuit equation of a motor, based on the command current and the angular speed. A dq-axis/three-phase converter converts the command voltage into a three-phase command voltage. A resistance calculator and a ?-value calculator respectively determines circuit resistance including armature winding resistance and a number of armature winding linkages which are included in the circuit equation of the motor, based on temperature of the motor detected by a temperature sensor and with reference to a table or the like which is stored in advance.

Abstract: 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.

Abstract: There is provided a compression molding machine capable of manufacturing briquettes by compression molding a material efficiently. The compression molding machine includes a mold device (12) formed with a molding chamber and a plunger (15) provided so as to be capable of advancing and retreating in the axial direction to compression mold the material in the molding chamber. The molding device (12) includes an axially fixed pressure receiving member (16) facing to a tip end surface (15a) of the plunger (15), an outside mold (44) in sliding contact with the outer peripheral surface of the plunger (15), and supporting means which supports the outside mold (44) so that the outside mold (44) moves in an extrusion direction of the plunger (15) in association with the movement of the plunger (15) in the extrusion direction.

Abstract: In a wheel spindle device wherein a plurality of grinding wheels are attached in a juxtaposed relation to a wheel spindle rotatably carried on a wheel head of a grinding machine, a reference position for specifying a position in the circumferential direction of the grinding wheel is provided on a core member of each of the grinding wheels, and a plurality of inclined grooves at predetermined angular intervals are formed on a grinding surface of each grinding wheel to be inclined relative to the circumferential direction of each grinding wheel. In order that the fluctuations in the dynamic pressure and the grinding resistance between respective grinding wheels and workpiece portions ground therewith do not grow as a combined or synergy effect, the inclined grooves on each grinding wheel are shifted in angular phase from those on another grinding wheel, so that grinding efficiency and accuracy can be enhanced.

Abstract: In an electric power steering apparatus, steering torque of a steering wheel is detected by a torque sensor, and a motor 10 for generating steering assist power is controlled so that the steering assist power is generated according to a basic assist torque corresponding to the detected steering torque. A correspondence relationship between the steering torque and the basic assist torque is set such that an assist gradient that is a rate of change of the basic assist torque to the steering torque varies according to variation of the steering torque. A correction amount of an output of the motor 10 varies according to the variation of the assist gradient.

Abstract: A tripod-shaped constant-velocity universal joint which makes downsizing feasible while reducing induced thrust force. A shaft-axis-wise width “bx” of the tripod-shaft portions of a tripod-shaped constant-velocity universal joint (i.e., a width of the tripod-shaft portions in a case where they are viewed from the torque transmission direction) is formed smaller as it goes from the root side to the leading-end side in the torque transmission region.

Abstract: A variable transmission ratio apparatus for effectively preventing ratcheting between a flexible spline and a circular spline caused by a steering operation performing in a locked state. A variable transmission ratio apparatus includes a strain wave gear mechanism for adding rotation resulting from motor drive to rotation from an input shaft resulting from a steering operation and transmitting the added rotation to an output shaft, a housing accommodating the strain wave gear mechanism and the motor and fixed to a non-rotating portion, and a lock device for locking the housing and a motor shaft in a manner prohibiting relative rotation therebetween. Among the circular splines forming the strain wave gear mechanism, the number of teeth of the circular spline connected to the output shaft is greater than the number of teeth of the circular spline connected to the input shaft.

Abstract: In an evaluation apparatus of a hub unit, a signal processing unit outputs frequency analysis signals which indicate such a result obtained by that an output signal of an acceleration sensor fixed on a hub unit by a magnet is processed via an A/D converting unit and an envelope detecting unit, and thereafter, the processed sensor signal is analyzed for a frequency analysis by an FFT unit. Then, an evaluation output unit evaluates damage conditions of the hub unit based upon signal strengths of specific frequencies, and overall values, which are acquired from the frequency analysis signals, and then, outputs the evaluated damage condition to a display unit.

Abstract: An electric power steering apparatus includes a charge-discharge circuit including a circuit charging an auxiliary power supply by turning on and off an MOS-FET for voltage boosting and that selectively configures a first output mode in which an electric power is supplied to a motor by a first electrical conduction path to which a voltage of a battery is applied or a second output mode in which the electric power is supplied to the motor by a second electrical conduction path to which a voltage of a source of the series-connected battery and auxiliary power supply is applied. When a failure of the battery is detected, the electric power steering apparatus connects the first conduction path to an electrical conduction path to ground by continuously holding the MOS-FET in an on-state and drives the charge-discharge circuit to select the second output mode, thereby configuring a circuit to supply the motor with the electric power only from the auxiliary power supply.

Abstract: A machining center wherein improved workability of a control board, a widened movable zone of a column and a reduced installation space are achieved. The machining center includes a column movably supported on a column sliding portion in an X-axis direction, a work table movably supported on a table sliding portion in a Z-axis direction, a main spindle head slidably supported on the column in a Y-axis direction, and an automatic tool changer disposed at an inner side of the column sliding portion. The control board is arranged at an opposite side of the automatic tool changer and is provided in parallel with a side surface of a front portion of a table sliding portion and is arranged side by side with an openable/closable door for an operator provided on a side surface of a cover in a vicinity of a rear end portion of the side surface of the table sliding portion.

Abstract: When a source consisting of series-connected battery 7 and auxiliary power supply 9 supplies an electric power to a motor 4, a MOS-FET 13 for preventing a current induced by a voltage of the auxiliary power supply 9 from being reversed upstream should be off if it operates normally. Therefore, voltages at the opposite terminals of the MOS-FET 13 should have a difference which corresponds to a voltage of the auxiliary power supply 9. Hence, the voltages at the opposite terminals of the MOS-FET 13 are detected by two voltage detectors 23 and 25 when the electric power from the auxiliary power supply 9 is supplied to the motor 4. If the potential difference between the voltages at the opposite terminals of the MOS-FET 13 is equal to or less than a predetermined value, a control circuit 24 issues a failure signal upon determination that the MOS-FET 13 suffers a short-circuit fault. A MOS-FET 15 is also monitored in the same way.