| 摘要 |
PROBLEM TO BE SOLVED: To provide a means for inhibiting rotation of a lower gear case even when an object hits a grinding wheel cover. SOLUTION: An anti-loosening member 7 is disposed between a recessed portion 2a of an upper gear case 2 and a recessed portion 3a of the lower gear case 3. When the lower gear case 3 tries to rotate relative to the upper gear case 2, the anti-loosening member 7 functions like a wedge, thereby inhibiting the rotation of the lower gear case 3. A rib 7b of the anti-loosening member 7 abuts against a protruded portion 2d of the upper gear case 2, thereby inhibiting movement of the anti-loosening member 7. COPYRIGHT: (C)2011,JPO&INPIT |
