| 摘要 |
In a helical-scan video recorder a plurality of magnetic heads (16, 17) rotate past a magnetic tape (21) which is guided along a substantially helical path round a tape guide member (13, 19) by a tape-supporting edge (22), the tape being transversely loaded in the direction of the tape-supporting edge with the aid of pressure members. The tape-supporting edge (22) has a convex curvature with a peak (T) substantially mid-way between a tape-support entry point (B) and a tape-support exit point (E), the curvature at the peak having a smaller radius than the curvature in the remaining part of the tape-supporting edge. The pressure members (66, 67) are situated beyond the ends of the tape-supporting edge (22) and the magnetic tape (21) is curved over the tape-supporting edge (22) in the plane of the magnetic tape in conformity with the convex curvature of the tape-supporting edge, so that the magnetic tape is pressed against the tape-supporting edge with a transverse force which is at least approximately constant per unit of length (Fig. 10).
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