Ratchet type one-way clutch apparatus
A ratchet type one-way clutch apparatus in which all pawl members are engageable with tooth portions stably, is provided. The one-way clutch 1 comprises an outer race 2 , an inner race 3 and a first to nth pawl members 4 a to 4 c . A plurality of tooth portions 5 are formed on the outer circumferential surface of the inner race 3 , and engageable with the first to nth pawl members 4 a to 4 c . A first to nth pawl member holding portions 12 a to 12 c are formed on the inner circumferential surface of the outer race 2 for holding the first to nth pawl members 4 a to 4 c . Biasing members 15 a to 15 c are held in the first to nth pawl member holding portions 12 a to 12 c for urging the first to nth pawl members 4 a to 4 c . The second to nth pawl member holding portions 12 b, 12 c are provided at positions deviated by arbitrary angles from positions where the inner circumferential surface of the outer race 2 is divided into n equal parts in the circumferential direction with reference to the position of the first pawl member holding portion 12 a , viewed from a central axis O of the outer race 2.
1. A ratchet type one-way clutch apparatus comprising:
a cylindrical outer race;
a cylindrical inner race arranged radially inside the outer race and rotatably relative to the outer race;
a first to nth pawl members, wherein “n” is an integer not less than 2, disposed on an inner circumference side of the outer race rotatably in the radial direction;
a plurality of tooth portions formed on the outer circumferential surface of the inner race, the tooth portions being engageable with the first to nth pawl members;
a first to nth pawl member holding portions formed on the inner circumferential surface of the outer race for holding the plurality of the pawl members;
biasing members held in the first to nth pawl member holding portions for urging the first to nth pawl members towards the inner race side;
the second to nth pawl member holding portions being provided at positions deviated by arbitrary angles from positions where the inner circumferential surface of the outer race is divided into “n” equal parts in the circumferential direction with the first pawl member holding portion as reference, viewed from a central axis of the outer race;
the first to nth pawl members each comprising, viewed from one axial side, a circular portion;
the first to nth pawl member holding portions each being provided, viewed from one axial side, with a circular first concave portion concaved from the inner circumferential surface of the outer race radially outwardly;
the circular portions of the first to nth pawl members being held rotatably in the first concave portions in the first to nth pawl member holding portions;
the biasing members being disposed respectively between the first to nth pawl members and the first to nth pawl member holding portions; and
an interval between a rotation center of the first pawl member and a point of action onto which the biasing force of the biasing member held in the first pawl member holding portion acts, being larger than an interval between a rotation center of the second to nth pawl member and a point of action onto which the biasing force of the biasing member held in the second to nth pawl member holding portion acts.
2. The ratchet type one-way clutch apparatus according to claim 1 , wherein
the first to nth pawl members each comprise, viewed from one axial side, the circular portion and a rectangular pawl portion formed integrally with the circular portion;
the first to nth pawl member holding portions each are provided, viewed from one axial side, with the first concave portion and a rectangular second concave portion formed circumferentially adjacent to the first concave portion and continuously thereto and concaved from the inner circumferential surface of the outer race radially outwardly; and
each one of the pawl portions of the first to nth pawl members and the biasing members is disposed in the second concave portion in the first to nth pawl member holding portion.