Motion transmission apparatus with a chain

A transmission apparatus with a chain, comprising:

• an elongated shaft defined with a rolling groove;
• a movable member defined with an accommodation portion for insertion of the elongated shaft, and in the accommodation portion being formed a rolling groove for cooperating with the rolling groove of the elongated shaft to form a load path;
• at least one circulating member fixed on the movable member and defined with a return path which is connected to the load path to form an endless circulation path;
• a plurality of rolling elements received in the endless circulation path as a transmission medium between the elongated shaft and the movable member;
• a chain including a plurality of spacers and two links two links, each of the spacers including a longitudinal direction and a transverse direction, one side of each of the spacers in the longitudinal direction being convex, and another side of each of the spacers in the longitudinal direction being concave, and the both sides of each of the spacers in the longitudinal direction being V or U-shaped, the two links being located at both ends of the respective spacers in the transverse direction to hold the spacers together in such a manner that the spacers are equidistantly spaced from one another by a receiving space which is provided for holding the rolling elements;
• wherein the concave one side of each of the spacers is formed with a first retaining surface, and the concave another side of each of the spacers is formed with more than one second retaining surface, and the first and second retaining surfaces are all in contact with the rolling elements;
• more than one oil-storage space appears in each of the receiving spaces for storage of lubricant oil, after the rolling element are received in the receiving spaces.