| 摘要 |
<p>PURPOSE:To prevent deterioration in recording and reproducing characteristic by checking light of a light emitting element with a photodetector to detect the end of a tape when a reel arranged between reels on the supply and receiving sides is wound completely on one hand so that dust and dirts are made hard to enter. CONSTITUTION:Furning forces of reel shafts 11a and 11b are transmitted to turn a reel 2a on the supply side and a reel 2b on the winding side and a magnetic tape 3 is wound onto the reel 2b from the reel 2a. At this point. light R radiated to respective photodetectors 12a ad 12b on the sides of the reels 2a and 2b is shielded with a tape wound covering a winding surface of the tape and hence, none of the light emitted from light emitting elements 10a and 10b is detected. But as the tape 3 is wound with the reel 2b to reach the end of the tape, the light R from the element 10a is detected with the photodetector 12a thereby allowing the detection of light reaching the tape end. Conversely when the tape 3 is wound with the reel 2a. the same is done.</p> |
