Ntn Corporation

Bridgestone Corporation

Kabushiki Kaisha Bridgestone

Takashi Nozaki

Tomoaki Makino

Takahide Saito

Tatsuo Kawase

Ken Yamamoto

Keisuke Sone

Masuo Takaki

Hiroyuki Hakamata

Yutaka Tanigaki

Yasuhiro Suzuki

Makoto Yasui

Shiro Goto

Hirokazu Ooba

Hiromi Nojiri

Taisuke Igi

Naoshi Hattori

Katsumi Tashiro

Takeshi Kohara

Katsumi Furutani

Satoshi Utsunomiya

Yoshihiko Hayama

Isao Mikuriya

The retainer is provided so as to be prevented from being rotatable with respect to the rotary shaft, and rotation of the input-side rotary member is reduced in speed and transmitted to the output-side rotary member through intermediation of the balls which engage with both of the ball engagement grooves. A raceway center line of the second ball engagement groove is formed of a wave-shaped curve. When a speed reduction ratio of the speed reducer is represented by 'i', the wave-shaped curve has such a shape that the balls which engage with the first ball engagement groove engage with the second ball engagement groove at a given rotation angle (&#x3b8;) of the input-side rotary member in a state in which the output-side rotary member is at a rotation angle (i&#x3b8;).

Speed reducer

A shaft coupling includes plates fitted on ends of input and output shafts, respectively. A plurality of guide grooves are formed in the opposed surfaces of the plates, respectively, so that each of the grooves extends perpendicular to the corresponding groove formed in the other plate. A steel ball is disposed between each pair of guide grooves of the plates at a portion where the pair of grooves cross each other. When the steel balls are pushed by the driving plate, they push the driven plate while rolling in the guide grooves, with their movements restricted by a retainer in the radial direction of the plates. Thus, large power can be smoothly transmitted between the rotary members with less frictional resistance. The offset amount can be changed easily. Between the plates, there are only the steel balls and the retainer.

Shaft coupling

A rotating side case supporting the rotor of an in-wheel motor and a wheel or a hub are interconnected by a flexible coupling which comprises a motor-side plate and a wheel-side plate having a plurality of grooves and a plurality of grooves formed on their opposed surfaces in the circumferential direction at an angle of 45&#xb0; from the radial direction of the plates and extending in directions orthogonal to each other, respectively, small balls sandwiched between the grooves and in such a manner that they can slide, and an intermediate plate interposed between the above plates and having guide holes for guiding the small balls in a direction orthogonal to the radial direction of the plates and which has a small number of parts and is easily assembled.

In-wheel motor system

A wind driven electrical power generating apparatus includes a rotor rotating by receiving wind force, a gear assembly having an input shaft connected to the rotor, a generator connected to an output shaft of the gear assembly, a sensor for detecting generating capacity of the generator and a controller for varying gear ratio of the gear assembly based on a signal from the sensor. In this construction, the controller controls so that the generator keeps rotating at around the lowest rotational speed within a range of rotational speed, the range being determined so as to include a maximum power operation region of the generator. Alternatively, the controller controls so that rotational speed of the output shaft of the gear assembly is adjusted to at around the lowest rotational speed within a range of rotational speed, the range being determined so as to include a rated power region as an upper operational limit.

Wind driven electrical power generating apparatus

A power transmission device is proposed which makes it easy to start on a slope. A control type slip clutch and a mechanical type control type two-way clutch are mounted between an input shaft to which the rotation of an engine is transmitted and an output shaft mounted around the input shaft. The input shaft and the output shaft are engaged together by the slip clutch while producing slip, and thereafter the two-way clutch is engaged. This improves transmission efficiency. A one-way clutch is provided between the output shaft and a housing provided around the output shaft. In a stopped state on an upward slope, when depressing of the brake pedal is released and rotation in the reverse direction to the revolving direction of the engine is transmitted to the output shaft from the vehicle wheel side, the output shaft is locked by the operation of the one-way clutch, thereby preventing the vehicle from moving in the opposite direction to the moving direction.

Power transmission device

A power cut/connect device is proposed which is axially compact and is usable in a limited space. The device includes a first input member coupled to a power shaft, an output member mounted coaxially with the first input member, a first two-way clutch provided between the first input member and the output member, a second input member coaxially mounted with the output member, a second two-way clutch provided between the output member and the second input member so as to be disposed coaxially with and around the first two-way clutch, and a control unit for controlling the first and second two-way clutches for interruption and connection of power.

Power cut/connect device

A valve lifter includes a guide cap mounted between a cam and the top end of a valve stem and which is slidably supported so as to be capable of moving in the axial direction. The guide cap has an end wall formed with a threaded through-hole. An adjusting bolt is threadedly engaged in the threaded hole. The adjusting bolt is biased toward the valve stem by a spring. The threaded hole and the adjusting bolt have serration-shaped threads so that the adjusting bolt can be moved toward the valve stem under the force of the spring. Since the adjusting bolt is threaded into the threaded hole formed in the guided cap, the axial length of the valve lifter is short.

Valve lifter

A direct valve drive device which can open and lose a valve with accuracy even if a negative valve clearance forms between the cam and the valve stem due to a difference in thermal expansion coefficient between the cylinder head made of aluminum alloy and the iron valve. A valve lifter is mounted between the cam and the valve stem being biased toward the cam by a valve spring. An adjuster bolt is threaded into a threaded hole formed in the valve lifter. The force of a spring is applied to the adjuster bolt so that the adjuster bolt move, while rotating, toward the valve stem. Formed between the threadedly engaging portions of the adjuster bolt and the threaded hole is an axial hole which is smaller than the height of a ramp formed on the cam but large enough to absorb any difference in thermal expansion between the cylinder head and the valve. Even if the valve clearance changes toward the negative side, the axial gap absorbs such a change, thus preventing the valve from being pushed by the base circle of the cam.

Plating 5 having good slide friction characteristics is applied onto the pocket surfaces 4a1, 4a2, which are opposite each other in the circumferential direction of the pockets 4a of the carrier and onto the end face 4a3 in the axial direction. It is possible to improve the lubrication conditions at the contacting area of the outer circumferential surface of the planetary rollers and the pocket surface 4a1 of the carrier 4 by coating the plating 5 having good slide friction characteristics onto the pocket surfaces 4a1,4a2 of the pocket 4 of the carrier 4 and further onto the end face 4a3. That is, the friction force at the contacting area is able to be decreased by the plating 5 having good friction characteristics, whereby even in a case where the contacting area is lubricated with a little lubricant, thermal deterioration of the lubricant due to heat generation of the contacting area is suppressed and good lubrication actions can be expected.

Planetary roller type power transmission device

Friction type continuously variable transmission

An outer ring for a vibration proof homokinetic joint has inner and outer casings. Vibration proof members made of an elastic material are disposed between the inner and outer casings. The outer casing is formed on an inner peripheral surface thereof with protrusions angularly spaced therebetween. The inner casing is formed on an outer peripheral surface thereof with grooves angularly spaced therebetween to receive the protrusions therein with predetermined gaps formed therebetween and extending in the direction of rotation of the joint. The vibration proof members are mounted between the adjacent protrusions and between the inner peripheral surface of the outer casing and the outer peripheral surface of the inner casing.

Growing community of inventors

Shizuoka, Japan

Takashi Nozaki