| 摘要 |
[Problem] The present invention aims to provide, without an increase in cost, a directional indication structure for threaded bodies that enables the visual and tactile distinction between left-hand thread and right-hand thread threaded bodies, enables the identification, from the external appearance and the external surface, of which direction a threaded body should be rotated in order to be tightened or loosened, enables mass production and the like, has a good external appearance, and has form properties that do not impinge the properties inherent in the threaded body or the strength, etc. thereof. [Solution] Directional indicators are asymmetrically provided, in association with the direction of rotation of the threads, to the outer surface of a solid body constituting a threaded body, said directional indicators having corner portions which indicate the forward direction in the direction of rotation, and corner portions which indicate the direction in which the threaded body will advance when rotated in the forward direction in the direction of rotation. |
