Nippon Hoso' Kyokai

Other

Hitoshi Masuko

Yukio Kameyama

Takeshi Yoshida

Masaru Sakata

Keiichi Yaguchi

Yasuo Matsumoto

In a magnetic video tape recording and reproducing apparatus (VTR) having rotary magnetic video heads rotating in a direction substantially perpendicular to the direction of tape travel, the width of the magnetic tape is reduced substantially to one inch from the conventional two inches, and eight video heads for recording a video signal on the magnetic tape and for reproducing the video signal from the magnetic tape are mounted on the circumferential surface of a rotary head drum having a diameter substantially equal to two inches and are arranged to be equidistant from one another in the direction of circumference of the rotary head drum. According to this invention, a compact VTR can be realized. In addition, the video signal may be transferred to and from the rotary head drum alternately through one of two circuit paths composed of a signal coupling means and an input/output circuit respectively, in order to realize a more compact, light weight and low power consumption VTR. Further, in order to improve the tape tracking accuracy in the case of such a narrow-width video head, use is made of a control signal whose n cycles of pulses in a pulse series obtained from a drum tachometer pulse are eliminated when a frame reference signal occurs so as to multiplex the pulse series with the frame reference signal. A control signal track is disposed at or around the minimum stretch portion or the center of the magnetic tape in the direction of the tape travel, and the tape travel is controlled by integral, differential, local proportional and proportional control systems, so as to further improve tape tracking accuracy.

Eight-head magnetic video tape recording and reproducing apparatus with

A dynamic pressure type floating head system comprising a floating magnetic head, a magnetic recording medium which stores information to be recorded and a resilient member for supporting the magnetic head. The floating head comprises a first flat surface portion of a sliding surface and a second flat surface portion having embedded therein a plurality of projections on the same plane. The attractive force caused by the viscous flow generated between the first surfaces by the relative movement of the surface to be recorded is combined with the holding force caused by the slip flow generated between the second surfaces so that the floating gaps are narrowed. The relative speed between the floating head and the surface to be recorded, the relationships between gaps, and operations of the approaching stroke to a floating position and of the separating stroke from the floating position exhibit a hysteresis characteristic, so that the magnetic recording and reproducing device requires no protective device for protecting contact between the floating head and the magnetic surface to be recorded.

Dynamic negative pressure type floating head system

Growing community of inventors

Sagamihara, Japan

Hitoshi Masuko