Harmonic Drive Systems Inc.

Keiji Ueura

Noboru Takizawa

Xin Yue Zhang

Stéphanie Moune

Yoshihide Kiyosawa

Toshimi Yamagishi

Sohei Beppu

A retainer for a roller bearing holds needle rollers within slit-shaped pockets which are formed separately by means of partitions arranged with a fixed pitch in the circumferential direction. Each partition is equipped with two side faces, which face the sides of the adjacent partitions, and an outer-circumferential-side end face, which faces the outer circumferential side of the retainer, and retaining protrusions are formed at the corner parts where the outer-circumferential-side end faces and each side face intersect. Each retaining protrusion protrudes farther to the outer circumferential side from the outer-circumferential-side end face, and protrudes obliquely in the direction in which the aperture width of the pockets is narrowed. For each pocket the positions where the retaining protrusions are formed in the longitudinal direction of the partitions are set so as not to overlap the adjacent pockets.

Retainer for roller bearing and needle roller bearing

The flexible bearing of the wave generator for a wave gear device is a deep-groove ball bearing in which an outer race and an inner race form an annular flexible bearing ring capable of bending in a radial direction. A ball diameter Da is set to be 5 to 15% greater than that of each model of the currently available product. Dimensions of orbital plane radii ro, ri of the inner and outer races are set so that the ratio ro/Da of the orbital plane radius ro of the inner race and the ball diameter Da, as well as the ratio ri/Da of the orbital plane radius ri of the outer race and the ball diameter Da, are both in the range of 0.51 to 0.52. With this configuration, the service life of the flexible bearing can be extended.

Wave generator for wave gear device

In a wave linear motion mechanism () of a holding mechanism (), those portions of a flexible screw () where first and second male screws () are formed are elliptically deformed by first and second wave generators () installed on an input shaft (), and the first and second male screws () are respectively partially engaged with first and second female screws () of first and second circular nuts (). First and second holding members () are mounted on the first and second circular nuts (), respectively. When the input shaft () is rotated by a motor (), the first and second holding members () are opened or closed depending on the rotation direction to release or hold an object (W).

Wave type linear motion mechanism and holding mechanism

A flat type wave gear device is realized having a much improved load capacity. When d is an amount of radial flexing at a major axis location of a rim neutral circle of the flexible external gear of a flat type wave gear device flexed into an elliptical shape and t is the rim thickness of the flexible external gear, then(0.5237 Ln()&#x2212;1.32)&#x2266;(0.8728 Ln()&#x2212;2.2)when the reduction ratio R of the wave gear device is less than 80, and(1.5499 Ln()&#x2212;5.8099)&#x2266;(2.5832 Ln()&#x2212;9.6832)when the reduction ratio R of the wave gear device is 80 or more. Using this setting makes it possible to increase the tooth root fatigue limit strength of the flexible external gear, thereby making it possible to improve the load capacity of the flexible external gear.

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Azumino, Japan

Keiji Ueura