Power transmission device and manufacturing method thereof

摘要

A power transmission device includes a gear speed reduction mechanism which includes an input shaft, an input pinion provided on the input shaft, a rotary shaft other than the input shaft, and a gear incorporated to the rotary shaft, and a casing which accommodates the gear speed reduction mechanism. The casing is made of resin and includes a casing body which includes an incorporating opening for incorporating the gear and a cover which closes the incorporating opening. The casing body includes an input side opening with the opening being a size that the input pinion can be inserted but the gear cannot be inserted. In addition, the rotary shaft is supported by a bearing support which is formed in the casing body, and the bearing support of the rotary shaft is not formed on the cover.

主权项

1. A power transmission device comprising:
a gear speed reduction mechanism which includes an input shaft, an input pinion provided on the input shaft, a rotary shaft other than the input shaft, and a gear incorporated to the rotary shaft, wherein the gear is integral to the rotary shaft or is fixedly attached to the rotary shaft; and a casing which accommodates the gear speed reduction mechanism, wherein the casing is made of resin and includes a casing body which includes an incorporating opening for incorporating the gear and a cover which closes the incorporating opening, wherein the casing body includes an input side opening with the opening being a size that the input pinion can be inserted but the gear cannot be inserted, and wherein the rotary shaft is supported by a bearing which is supported by the casing body, and the bearing of the rotary shaft is not formed on the cover, wherein a recess is formed in an inner end side of the incorporating opening, and the cover also closes the recess, wherein a ring-like stiffened member made of metal is disposed in the recess, wherein the input side opening and the incorporating opening are provided on opposite surfaces of the casing body respectively, wherein a recess is formed in the cover, and a portion of the gear enters the recess, and wherein the ring-like stiffened member is in contact with the cover.