| 摘要 |
<p>PROBLEM TO BE SOLVED: To prevent a cut and a crack likely to be produced in a core of a rotary transformer from being increased by providing a stator core and a rotor core, and further providing a fine groove adjoining to a coil accommodation groove in an opposite surface of the core. SOLUTION: A fine groove 12a is provided in a ring shape between an outer peripheral edge 5a of a lower core 5 and a coil accommodation groove 7, and a fine groove 12b is provided in a ring shape between an inner peripheral edge 5b and the coil accommodation groove 7. Hereby, when a cut 10a is produced in the outer periphery, the crack 10a is likely to increase up to the inside of the core 5, but it is prevented from being increased there by the fine groove 12a and from reaching the coil accommodation groove 7. Also when cracks 11a, 11b are produced, such an increase is likewise interrupted and the cracks are prevented from reaching the coil accommodation grooves 7, 9.</p> |
