drehkopf drum units

摘要

A rotary head drum unit for a recording/reproducing apparatus comprises a stationary upper drum (2) provided at its lower end with a taper surface (6) for biasing a magnetic tape (8) downwardly, a stationary lower drum (3) provided at its circumference with a helical tape lead (7) to guide the lower edge (8a) of the tape (8) helically extending across the upper and lower drums (2,3), and rotary heads (4) positioned for rotation between the upper and lower drums (2,3). At least a portion of the taper surface (6) of the upper drum (2) in a lead-out region (11) near a departing position at which the tape (8) departs from the rotary head drum unit is a helical taper section (6a) extending helically substantially in parallel with the helical tape lead (7) of the lower drum (3). The taper surface (6) having the helical taper section (6a) is able to bias the tape (8) downwardly in the lead-out region (11) so that the lower edge (8a) of the tape (8) is guided securely by the helical tape guide (7) of the lower drum (3) and keeps the upper edge (8b) of the tape (8) taut over the entire arc ( theta 1) of contact of the tape (8) with the rotary head drum unit, so that the tape (8) is secured for stable running. IMAGE