Rotating magnetic head device

Abstract

Abstract PURPOSE:To shorten the length of the axis of the rotating magnetic head and make VTR compact by providing the rotating number detecting means and the position detecting means of the non-commutator motor around the rotor of the non-commutator motor in the fixed drum. CONSTITUTION:On the lower surface of the yoke 17 in the fixed drum 5, print circuit board 38 is mounted at portion except the fixed member 19. On this printed circuit board 38, magnetic sensitive elements 39 are disposed around the rotor 20 at 60 spacings, the leakage magnetic flux of the rotor 20 is detected and the position of the rotor 20 is detected. On the board 38, iron core of shape 41 is mounted. The iron core 41, the circumference wall of the rotor cover 22 and the teeth shape protrusion 43 constitute the magnetic circuit of magnetic flux of the permanent magnet. Accordingly, when the teeth shaped protrusion 43 together with thr rotor 20, the magnetic flux changes periodically. This is detected by the detecting coil 42 to obtain the number of the rotation of the rotating drum. According to the such construction, the axis length of the rotating magnetic head can be shortened and VTR be made compact.

Inventors

• 👤 Shigeki Morinaga
• 👤 Seiji Yamashita
• 👤 Kunio Miyashita
• 👤 Tadashi Takahashi
• 👤 Takeo Maeda

Bibliographic Details