Strain wave gearing
AssigneeHarmonic Drive Systems Inc.
InventorsYuya MURAYAMA, Yoshihide KIYOSAWA
Life of this patent
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Abstract
A hollow-type strain wave gearing unit has a cup-shaped flexible externally-toothed gear, in which one shaft end portion of a hollow rotation shaft of a wave generator is located. The shaft end portion is supported by a bearing mounted on a bearing holder fixed to a boss of the flexible externally-toothed gear. The bearing holder has a retainer holding portion to prevent a retainer of a wave generator bearing from coming off in the axis line direction. There is no need to dispose a retainer holding plate of the wave generator bearing inside the flexible externally-toothed gear, whereby the axial length of the hollow-type strain wave gearing unit can be reduced.
Claims4
A strain wave gearing, comprising:
- a rigid internally-toothed gear;
- a cup-shaped flexible externally-toothed gear arranged inside the rigid internally-toothed gear, and capable of meshing with the rigid internally-toothed gear;
- a wave generator disposed inside the flexible externally-toothed gear and flexes the flexible externally-toothed gear into an ellipsoidal shape to mesh partially with the rigid internally-toothed gear;
- a boss defining a center portion of a cup bottom of the flexible externally-toothed gear;
- a bearing holder arranged inside the flexible externally-toothed gear and fixed to the boss;
- a boss side bearing that is mounted on the bearing holder, and that supports a shaft end portion of the wave generator located on a side of the boss in a freely rotating state from an outer peripheral side;
- and
- a retainer holding portion that is formed on a holder end face of the bearing holder facing a side of the wave generator, and that faces, with a prescribed gap, a retainer of a wave generator bearing of the wave generator.
Dependencies are inferred from the claim text.