Patent ID: 9568051
Date: 2017-02-14
CPC Classifications: E05Y,F16D

Claim:
1. A spring type one-way clutch comprising: a tubular outer member including an inwardly extending flange at a first end of the outer member and having an opening at a second end of the outer member; an inner member inserted in the outer member so as to be coaxial with the outer member; a clutch spring mounted between a radially inner surface of the outer member and a radially outer surface of the inner member; and a lid closing the opening of the outer member; wherein the inwardly extending flange of the outer member has an inner tubular portion on an inner side surface of the flange; wherein the clutch spring comprises a large-diameter coil spring portion fitted on a radially outer surface of the inner tubular portion with an interference fit, a transition portion having a starting point connected to an end of the large-diameter coil spring portion, and extending radially inwardly from the starting point to an end point of the transition portion in a spiraling pattern in a direction in which the large-diameter coil spring portion is wound such that none of the portion of the transition portion other than the starting point is radially aligned with the starting point, and a small-diameter coil spring portion extending from the end point of the transition portion so as to be located in the large-diameter coil spring portion, wherein the small-diameter coil spring portion is wound in a direction different from the direction in which the large-diameter coil spring portion is wound, and wherein the small-diameter coil spring portion is fitted on a cylindrical radially outer surface of the inner member with an interference fit; and wherein the inner tubular portion has an axial length determined such that a distal end surface of the inner tubular portion abuts the inner side surface of the lid, or the distal end surface of the inner tubular portion axially faces the inner side surface of the lid with a minute gap left therebetween, and wherein a spiral groove is formed in the distal end surface of the inner tubular portion in which the transition portion of the clutch spring is received.