A rotary head device for a recording and reproducing apparatus includes a rotary drum and a stationary drum. The rotary drum has a guide surface formed of a conical surface coaxial with the axis of rotation of the rotary drum and wound with a magnetic tape. A head unit is mounted on the rotary drum to be rotatable integrally therewith. The head unit includes two head elements facing each other, for scanning the tape wound on the guide surface, while the tape is being interposed between the head elements, as the rotary drum rotates.

A rotary magnetic head drum apparatus is constituted by at least one video head, a rotary drum having a tape running surface and a head mounting surface to which the video head is securely mounted, and a stationary drum provided with a tape guide and a tape running surface. In the rotary magnetic head drum apparatus, the tape running surface or the rotary drum has a lower end portion which is formed with a tapered portion whose diameter becomes gradually smaller along the axis of the rotary drum, and the tapered portion is projected such that its bottom end surface is located below the plane of the head mounting surface.

A rotary head drum unit for a recording/reproducing apparatus comprises a stationary upper drum provided at its lower end with a taper surface for biasing a magnetic tape downward, a stationary lower drum provided in its circumference with a helical tape lead or guide surface to guide the lower edge of a tape helically extended across the upper and lower drums, and rotary heads inserted between the upper and lower drums. At least a portion of the taper surface of the upper drum in a lead-out region near a position where the magnetic tape departs from the rotary head drum unit is a helical taper section extended helical substantially in parallel to the helical tape lead or guide surface of the lower drum. The taper surface having the helical taper section is able to bias the magnetic taper downward in the lead-out region so that the lower edge of the magnetic tape is guided securely by the helical tape guide surface of the lower drum and keeps the upper edge of the magnetic tape taut through the entire arc of contact of the magnetic tape with the rotary head drum unit, so that the magnetic tape is secured for stable running.

A rotary bead-drum assembly for use in a video tape recorder that makes high-density recording. The assembly comprises a rotating top drum and a stationary bottom drum. Magnetic tape is helically wound on the outer surfaces of the two drums. A plurality of magnetic transducing heads are mounted to the top drum. An upward conical surface is formed on the top drum over the heads to make the elongation coefficient of the lateral extent of the tape uniform.

A rotating intermediate drum having mounted thereon optical head is made smaller than stationary upper and lower drums in diameter and spiral grooves are formed on the rotating intermediate drum on its surfaces opposing the stationary upper and lower drums. An optical tape is transported in a floated condition relative to a drum circumferential surface owing to a synergy of a dynamic pressure based on the rotation of the rotating intermediate drum and the air exhausted from the spiral grooves. Therefore, an information signal is recorded on and/or reproduced from the optical tape when the optical tape is transported in the floated condition from the head drum having the trilayer structure composed of the stationary upper and lower drums and the rotating intermediate drum therebetween.