| 摘要 |
PROBLEM TO BE SOLVED: To prevent the loading work of a recording medium from becoming difficult since the recording medium is contacted with the end surface of the recording medium socket. SOLUTION: The recording medium socket 3 is arranged so that a size difference X1 between the inner surface 2a of an introducing opening 2 and the inner surface 3a of the recording medium socket 3 in one side A becomes, in the sectional view of the plan view direction of the loaded recording medium 1, larger than the size difference X2 between the inner surface 2b of the introducing opening 2 and the inner surface 3b of the recording medium socket 3 in the other side B. In addition, the socket 3 is arranged so that a size difference Y1 between the inner surface 2a of the introducing opening 2 and the inner surface 3a of the socket 3 becomes, in the sectional view in the side view direction of the loaded recording medium 1 in one side C, larger than a size difference Y2 between the inner surface 2b of the introducing opening 2 and the inner surface 3b of the socket 3. |
