| 摘要 |
<P>PROBLEM TO BE SOLVED: To solve such a problem that a stable production system cannot be secured for a conventional bridge breaker device including a turning ring bearing which requires significantly high cost and a long delivery period when manufactured, and is ordered on a small-quantity basis, thus possibly resulting in the refusal of manufacturing, and the further precise machining of the turning ring bearing itself, fitted hollow cylinders and a casing is also required to cause a cost increase, because fitting parts should be fitted to each other with no clearance to cover the insufficient rigidity of the turning ring bearing itself. <P>SOLUTION: In the inner face of the casing and the outer faces of the hollow cylinders, grooves semicircular in cross section are formed, respectively. Balls are provided in a space circular in cross section formed with the grooves fitted to each other. <P>COPYRIGHT: (C)2012,JPO&INPIT |
