Nsk Corporation

Kazutaka Tanaka

Yasuyuki Matsuda

Daisuke Gunji

Hiroyasu Yoshioka

Takashi Imanishi

Masafumi Hikida

Eiji Inoue

Tetsu Takehara

Tomoharu Saito

Yuka Kaneko

Tsutomu Hibi

Ryo Segawa

Tohru Ueda

Tooru Ueda

A ball screw device has: a screw shaft rotationally moving during use, a nut having a protruding non-rotating side engaging portion at an end portion on one side in an axial direction, the nut linearly moving during use, balls arranged between a shaft-side and nut-side grooves, and a driving member fixed to the screw shaft having an arc-shaped rotating-side engaging groove portion into which the non-rotating side engaging portion can be inserted in the axial direction, and which can be engaged with the non-rotating side engaging portion in a circumferential direction.

Ball screw device

A rotation transmission device having a high torque measurement resolution is provided. The rotation transmission device is provided with: a rotary-shaft unit () having a first and second rotary shaft () combined so as to be coaxial and such that the end sections thereof can rotate relative to each other and a torsion bar () that is provided on the inner-diameter side of the first and second rotary shafts so as to be coaxial therewith, has one end section connected to the first rotary shaft (), and has the other end section connected to the second rotary shaft (); a first gear () fastened to the outer peripheral surface of the first rotary shaft (); a second gear () fastened to the outer peripheral surface of the second rotary shaft (); a coupling shaft () provided on the inner-diameter side of the torsion bar () so as to be coaxial therewith, having one end section connected to one rotary shaft (), and having the other end section protruding from an end of the torsion bar () in the axial direction; a first encoder disposed and fixed on the other end of the coupling shaft () so as to be coaxial with the first rotary shaft () and having a first detected section (); a second encoder fastened on the other end of the second rotary shaft () so as to be close to the first encoder and having a second detected section (); and a sensor unit having at least one sensor () that faces the first and second detected sections ().

Rotation transmission device

A sun roller of a friction roller-type transmission includes a movable sun roller element () capable of moving in an axial direction. Furthermore, the sun roller is provided with a loading cam mechanism which is formed along the circumferential direction of an input shaft (), the loading cam mechanism having a first cam surface (), a second cam surface () arranged facing the first cam surface () and secured to the input shaft (), rolling elements () held between the first and second cam surfaces (), and an annular holding device (), and the loading cam mechanism axially displacing the movable sun roller element (). The holding device () has an inside-diameter-surface guiding part () for positioning the holding device relative to the input shaft by being fitted over the input shaft, the guiding part being provided to the inside diameter surface.

Friction roller-type transmission

A friction roller type reduction gear includes a first sun roller so mounted on an input shaft movably in the axial direction of the input shaft, a plurality of first cam grooves formed in the end face of the first sun roller, a cam plate so mounted on the input shaft as is opposed to the first cam groove side of the first sun roller, a plurality of second cam grooves so formed in the cam plate as are opposed to the first cam grooves, rolling elements interposed between the first and second cam grooves, and a cage for holding the rolling elements rollably, while a pitch circle diameter of the position for holding the rolling elements is different from pitch circle diameter of the first and second cam grooves.

Friction roller type reduction gear

In order to implement a structure capable of improving the resolution of torque measurement while preventing the plastic deformation of a torsion bar (), an input-side stopper () having an uneven shape (gear shape) in the circumferential direction is provided in a portion of an input-side rotating body () that includes an input shaft () and an input gear (), and an output-side stopper () having an uneven shape (gear shape) in the circumferential direction is provided in a portion of an output-side rotating body () that includes an output shaft () and an output gear (). The input-side stopper () and the output-side stopper () are combined so as to be engaged to be able to transmit torque only when the torsional angle within the elastic range of the torsion bar () reaches a predetermined amount.

Torque measurement device-equipped rotation transmission apparatus

Construction of a friction roller reducer is achieved wherein displacement of intermediate rollers due to the change in thickness in the axial direction of loading cam apparatuses can be performed smoothly, and excellent transmission efficiency can be obtained. Long guide holes that are long in the radial direction of a sun roller and ring-shaped roller are provided in guide blocks that are fastened to a support frame for supporting the end sections of rotation shafts of intermediate rollers. The outer rings of ball bearings, of which the inner rings are fitted around and fastened to the outside of the end sections of the rotation shafts, engage with the long guide holes so as to be able to displace in the radial direction of the sun roller and the ring-shaped roller.

Friction roller reducer and drive unit for electric automobile

A drive apparatus for an electric automobile in which a planetary gear transmissionis assembled for which it is possible to lengthen the traveling distance per one electric charge, and thus improve the convenience of the electric automobile. A planetary gear transmissioncomprises a first single-pinion planetary gear mechanismand a second double-pinion planetary gear mechanism, and after changing the power from first and second electric motorsby a desired gear ratio, transmits the power to a driven-side rotating shaft. A one-way clutchis provided between a first carrierand a portionthat is fastened to the vehicle so as to allow the first carrierto rotate in a specified direction and prevent the first carrierfrom rotating in a direction opposite the specified direction.

Drive apparatus for an electric automobile

Construction capable of improving the convenience of an electric automobile is achieved by making the drive apparatus for an electric automobile in which a planetary-gear transmissionis assembled more compact and simple, and increasing the distance traveled per charge. The planetary-gear transmissioncomprises a single-pinion first planetary-gear mechanismand a double-pinion second planetary-gear mechanism, and reduces power from an electric motorby a desired reduction ratio before transmitting that power to a driven-side rotating shaft. A first braking deviceswitches a ring gearand a second braking deviceswitches a second sun gearbetween a state of being allowed to rotate and a state of being prevented from rotating with respect to a fixed portion.

Growing community of inventors

Fujisawa, Japan

Kazutaka Tanaka