Nsk Corporation

Other

Technical University of Munich Department of Mechanical Engineering

Shinji Miyata

Takashi Imanishi

Hiroyuki Itoh

Hisashi Machida

Eiji Inoue

Hideki Hashitani

Hiroyuki Ito

Norihisa Kobayashi

Tatsuhiko Goi

Kenichiro Tanaka

Masami Tanaka

Kouji Ishikawa

Sumio Sugita

Tomoyuki Yanagisawa

Hirotoshi Aramaki

Toshirou Toyoda

Koji Kawakami

Daping Liu

Toshihiko Okamura

Hidekazu Watanabe

Takayuki Isano

Osamu Yoshimatsu

Michael Otto

Hiroshi Yanagino

Karsten Stahl

Naser Emamdjomeh

Maximilian Fromberger

A toroidal-type continuously variable transmission has a casing; a rotary shaft; a pair of outside disks each including an axial-direction one-side surface and supported on the rotary shaft so as to be rotated in synchronization with the rotary shaft; an inside disk including axial-direction two-side surfaces and rotatably supported on the periphery of the middle portion of the rotary shaft so as to be rotated with respect to the rotary shaft; support members disposed between the one side axial-direction surface and the axial-direction one-side surface so as to be swung and shifted about pivot shafts thereof; power rollers rotatably supported on the support members, the peripheral surface of the power rollers being contacted with the axial-direction two-side surface and the axial-direction one-side surface; and ball bearings for supporting the inside disk in such a manner that the inside disk is rotated with respect to the casing.

Toroidal-type continuously variable transmission and continuously variable transmission apparatus

A continuously variable transmission apparatus coupled to a drive source has an input shaft, an output shaft, a toroidal-type continuously variable transmission having a pair of input side disks an output side disk, a trunnion, a support shaft and a power roller, and the planetary gear mechanism having a sun gear, a ring gear, a carrier and a planetary gear, wherein a plurality of projections are projected from the one input side disk and provided at positions closer to the outside diameter than to the diameter of a pitch circle of a traction section being close to the outermost diameter of the input side disk, a plurality of engagement sections formed in the carrier, and transmission of power between the carrier and the one input side disk is carried out by coupling the plurality of projections with the plurality of engagement sections.

Continuously variable transmission apparatus

A plurality of projecting portions are provided on and projected from part of an outer peripheral surface of an input side disk. A plurality of transmitting projection pieces are provided on a base end portion of a transmission shaft. The transmitting projection pieces of the transmission shaft are engaged with the projecting portions of the input side disk to thereby be able to transmit torque between the input side disk and the transmission shaft.

A toroidal type continuously variable transmission having first and second discs supported around a rotating shaft and receiving power rollers therebetween includes a ball spline having a first spline groove formed in an outer circumferential surface of the rotating shaft, a second spline groove formed in an inner circumferential surface of the first disc, and balls provided between the first spline groove and the second spline groove rollably. An axial position of an end portion of an effective groove portion of the first spline groove is located to correspond to an axial position of an inner end portion of the second spline groove or more closely to the second disc than the axial position thereof when a pressing unit, a preload spring and the first disc are installed around the rotating shaft, pressure oil is not fed to the pressing unit, and the preload spring is not elastically deformed.

Toroidal type continuously variable transmission

A continuously variable transmission apparatus has clutch device having a low speed clutch; a high speed clutch; and, a controller switching the transmission state into any one of a low speed mode and a high speed mode by connecting any one of the clutches, wherein timings for signaling by the controller for switching the connected and disconnected states of the clutches vary according to the switching directions of the low speed and high speed modes; and, a timing for signaling for connecting the low speed clutch with respect to the moment for signaling for cutting off the connection of the high speed clutch in order to switch the high speed mode over to the low speed mode is set earlier than a timing for signaling for connecting the high speed clutch with respect to the moment for signaling for cutting off the connection of the low speed clutch.

A toroidal-type continuously variable transmission has: a casing; a rotary shaft; outside disks; an inside disk; support members; a plurality of support plates; an actuator body; a pair of support posts including support ring portions, the support ring portions respectively existing in middle portions between the inside disk and the outside disks, wherein the respective one-side end portions of the two support posts are connected and fixed to the actuator body in a state that the rotary shaft is inserted through the support ring portions of the two support posts, the axial-direction two end portions of the inside disk are rotatably supported on the support ring portions of the two support posts, and the support plates are supported on the neighboring portions of the respective two end portions of the two support posts.

A hydraulic type pressing device secures the contact pressure between the peripheral surfaces of respective power rollers and the inner surfaces of respective input side disks and respective output side disks. When a torque to be transmitted changes abruptly, the pressing force of the pressing device is set to a value corresponding to the maximum torque to be transmitted by a toroidal type continuously variable transmission. According to this configuration, the variation of the transmission ratio based on the variation of the elastic deformation values at the respective portions is suppressed to prevent the uncomfortable feeling of a driver.

Toroidal type continuously variable transmission and continuously variable transmission apparatus

An output rotational driving power of the engine is split into a first split power and a second split power. The first split power is transmitted to a continuously variable speed transmission that transmits the first split power by a shearing resistance of a fluid. The second split power is transmitted to a differential planetary gear system. An output power of the continuously variable speed transmission is transmitted to the differential planetary gear system to combine the first split power and the second split power in the differential planetary gear system. A variation of a rotating speed of the output rotational driving power is absorbed by the continuously variable speed transmission to adjust an output rotating speed of the differential planetary gear system to a constant speed.

Method of and apparatus for driving aircraft generator at a constant-speed

Between a water pump and an electric motor there is interposed a toroidal-type continuously variable transmission By changing the gear change ratio of the toroidal-type continuously variable transmission the water supply quantity can be changed while the electric motor is being operated at a constant speed.

Pump drive apparatus

In a toroidal type continuous variable speed transmission, a control valve for displacing trunnions is controlled by supporting and fixing a precess cam at an end of a rod displaced together with one of the trunnions. Therefore, when the torque inputted to the toroidal type continuous variable speed transmission is greatly varied by the treading on or releasing of the accelerator, there is the risk that an unnecessary variation of the gear ratio invite an abrupt change in engine revolutions and a consequent uncomfortable feeling on the part of the driver. A tip of a link arm is brought into contact with the cam face of a precess cam, and the control valve is switched according to any variation of the trunnion. Further, the contact position between the cam face and the tip of the link arm is placed closer to the input side disk side. This configuration makes it possible to suppress the influence of elastic deformation of trunnions and to solve the problem noted above.

Toroidal type continuous variable speed transmission

In the toroidal type continuously variable transmission system incorporating a power roller bearing therein, race grooves and respectively formed in the inner and outer races and of the power roller bearing are respectively structured in such a manner as to have an arc-shaped cross section, and the radii of curvatures of the arc-shaped cross sections of race grooves and are set in the range of 52% to 59% of diameter of a rolling ball body which can roll on these race grooves, thereby being able not only to restrict an increase in dynamic torque of the power roller bearing but also to improve life of the power roller bearing.

Power roller bearing and a troidal type continuously variable transmission system

In a continuously variable transmission comprising: an input shaft which is rotated by a drive source; an output shaft which takes out a driving force attributing the rotation of the input shaft; and a variator and a planet gear mechanism which are arranged between the input shaft and the output shaft, the variator having a clutch which provides a first mode in which a driving force circulation is carried out, and a second mode in which the driving force circulation is not carried out, the speed of a first driving force transmitting system which is inputted to the planet gear mechanism through the variator and the speed of a second driving force transmitting system which is inputted to the planet gear mechanism directly, not through the variator are detected with first and second speed detecting sensors, and, upon detection of the substantial coincidence in the ratio of speed of the first and second driving force transmitting shafts, the mode switching operation is carried out with the clutches.

Continuously variable transmission

This invention realizes a compact and light-weight structure having excellent durability and transmission efficiency. A toroidal type continuously variable transmission is provided around an input shaft concentric with a driving shaft, and a planetary gear mechanism is provided around an output shaft. This output shaft is disposed obliquely above the input shaft. By such disposition, the effective utilization of space is achieved, and compactness and lighter weight are realized.

A toroidal type continuous variable transmission system to be used as a transmission of an automobile comprises: an input shaft rotatably actuated by means of a drive source; an output shaft for acquiring power stemming from rotation of the input shaft; a variator which is interposed between the input and output shafts and includes a pair of input disks which rotate on the basis of rotation of the input shaft, a pair of output disks which are provided in a coaxial relationship with the input disks and rotate in synchronous with each other, and power rollers which are provided between the input and output disks while remaining in contact with the disks and which rotate at an angle; a planetary gear mechanism which is interposed between the input and output shafts and includes a sun gear, a ring gear provided around the sun gear, a plurality of planetary gears which are provided between the sun gear and the ring gear so as to be rotatable, and carriers supporting the planet gears; a pressing mechanism which presses the input or output disk against the output or input disk by way of the power rollers; a first power transmission mechanism which transmits the rotation of the output disks to the planetary gear mechanism; and a second power transmission mechanism which transmits the rotation of the input shaft to the planetary gear mechanism.

Toroidal type continuous variable transmission system

In a continuously variable transmission yokes for supporting pivot shafts provided on the end portions of trunnions are supported for displacement only in the axial direction of the pivot shafts and oscillation in a predetermined direction, relative to a support post fixed to the inner surface of a casing. By this construction, the contact pressure between the peripheral surfaces of a pair of power rollers supported on a pair of trunnions supported by the yokes and the inner sides of input side and output side discs is made uniform.

Growing community of inventors

Kanagawa, Japan

Shinji Miyata