JPH04141812A - Rotary head assembly of magnetic recording and reproducing device - Google Patents

Abstract

PURPOSE:To improve the signal precision of a rotation position detecting signal by means of a pulse generation device and to miniaturize and lighten a flange by directly fitting a motor magnet and a PG magnet fixed on the motor magnet to a rotary drum as the rotary side of rotary head. CONSTITUTION:This device consists of a fixed drum 3 which holds a shaft 2 and is fixed to the magnetic recording and reproducing device, the rotary flange 4 fixed on the outside of a bearing 1, the rotary drum 6 which holds the magnetic head 5 and is fixed on the flange 4, a PG substrate 8 on which the pattern of the pulse generation device fixed to a motor coil 7 is printed to confirm the rotary running position of the magnetic head 5 and a motor for rotating the rotary drum 6. Then, the motor magnet 9 is directly fitted to the rotary drum 6 without through the flange 4, and the PG magnet 10 to which the pattern of the pulse generation device is magnetized is directly fitted to the rotary drum 6. Thus, information of the rotary position of a generation signal by the pulse generating device is improved and the flange is miniaturized and lightened.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to a rotary head assembly for a magnetic recording/reproducing device, and particularly to one in which the arrangement of the motor is improved.

[Conventional technology]

FIG. 2 is a sectional view showing a rotating head assembly of a conventional magnetic recording/reproducing device. A fixed drum fixed to the deck base of the playback device,
4 is a flange that is fixed to the outside of the bearing 1 and rotates around a rotating shaft constituted by the bearing 1; 5 is a magnetic head; 6
7 is a rotating drum that supports a magnetic head 5 and is fixed to the flange 4 so as to rotate around a rotating shaft constituted by the bearing 1; 7 is a motor coil that is fixed to the fixed drum 3;
8 is a pulse generator (
PG) pattern is printed on it, 9 is a motor magnet fixed to the flange 4, and 10 is a PG magnet fixed to the motor magnet 9 and magnetized with a pattern of a pulse generator.

Next, the operation will be explained. In this rotating head assembly, a motor magnet 9 fixed to a rotating drum 6 is repelled or attracted by a magnetic field generated by a motor coil 7 fixed to a fixed drum 3, and the rotating drum rotates. When rotated by the coil 7 and motor magnet 9, once per rotation,
When the PG magnet 10 passes over the pattern of the PG board 8, a current is generated in the pattern of the PG board 8 according to Fleming's right-hand rule, resulting in a pulse signal.

Normally, this signal is used to confirm the rotational travel position of the magnetic head 5 attached to the rotating drum 6, and this signal is processed by a circuit and used for switching timing of the magnetic head 5, etc. .

[Invention or problem to be solved]

Since the rotary head assembly of the conventional magnetic recording/reproducing device is constructed as described above, the positional relationship between the magnetic head 5 and the PG magnet 10 tends to shift, and it is necessary to align the rotary drum 6 and the flange 4 in the rotational direction. Moreover, since the motor magnet 9 is attached to the flange 4, the flange 4 becomes large, which causes problems such as increased weight and increased material costs.

This invention was made to solve the above-mentioned problems, and it is possible to improve the rotational position accuracy of the signal generated by the pulse generator, and also to reduce the size and weight of the flange, allowing for lighter and cheaper magnetic recording and reproducing. It is an object of the present invention to obtain a rotary head assembly for a magnetic recording/reproducing device.

[Means to solve the problem]

A rotary head assembly for a magnetic recording and reproducing apparatus according to the present invention is such that a motor magnet and a PG magnet are directly fixed to a rotating drum without using a flange.

[Effect]

In this invention, with the above-described configuration, it is only necessary to extend the flange for attaching the motor magnet, so the drum can be made smaller and lighter, and the accuracy of detecting the rotational position of the pulse generator is improved. can be achieved.

〔Example〕

Embodiments of the present invention will be described below with reference to the drawings.

FIG. 1 shows a rotary head assembly of a magnetic recording/reproducing apparatus according to an embodiment of the present invention. In the figure, 1 is a bearing, 2 is a shaft fixed inside the bearing 1, 3 is a fixed drum that holds the shaft 2 and is fixed to the magnetic recording/reproducing device, and 4 is a bearing 1 fixed outside the bearing 1. 5 is a magnetic head; 6 is a rotating drum fixed to the flange 4 so as to carry the magnetic head 5 and rotate around a rotating shaft constituted by a bearing l; 7 is a motor coil fixed to the fixed drum 3, 8 is a PG board on which the pattern of the pulse generator fixed to the motor coil 7 is printed, 9 is a motor magnet fixed to the rotating drum 6, and 10 is a motor rotation This is a PG magnet fixed to the magnet 9 and magnetized with a pattern of a pulse generator.

Since the pulse signal generation operation of this embodiment is the same as the conventional one, the operation and effects of this embodiment will be explained below.

In this embodiment, as described above, the motor magnet 9 is connected directly to the rotating drum 6 without passing through the flange 4.
As a result, the flange 4 can be made smaller, its weight can be reduced, and it can be manufactured at low cost. Moreover, since the PC magnet 10 is also directly attached to the rotating drum 6, the accuracy of the rotational position detection signal by the pulse generator can be improved.

〔Effect of the invention〕

As described above, according to the present invention, since the motor magnet and the PG magnet fixed to the motor magnet are directly attached to the rotating drum on the rotating side of the rotating head, the rotational position detection signal from the pulse generator is In addition to improving signal accuracy, the flange can be made smaller and lighter, making it possible to provide a lighter and cheaper magnetic recording and reproducing device.

[Brief explanation of drawings]

FIG. 1 is a sectional view showing a rotary head assembly of a magnetic recording/reproducing apparatus according to an embodiment of the present invention, and FIG. 2 is a sectional view showing a conventional magnetic recording/reproducing apparatus. In the figure, 1 is a bearing, 2 is a shaft, 3 is a fixed drum, 4 is a flange, 5 is a magnetic head, 6 is a rotating drum, 7 is a motor coil, 8 is a PG board, 9 is a motor magnet,
10 is a PC magnet. In addition, in the figures, the same reference numerals indicate the same or equivalent parts.

Claims (1)

[Claims] (1) A bearing that constitutes a rotating shaft, a shaft that is fixed to or integrated with the inside of the bearing, a fixed drum that holds the bearing and is fixed to the main body of the magnetic recording/reproducing device, and a bearing that is fixed to or integrated with the outside of the bearing. a flange that rotates around a rotating shaft that is integrated with the flange, a magnetic head, and a rotating drum that supports the magnetic head and that is fixed to or integrated with the flange so as to rotate around the rotating shaft that is configured with the bearing. A rotary head assembly for a magnetic recording and reproducing device comprising: a pulse generator for confirming the rotational running position of the magnetic head; and a motor integrated with the pulse generator for rotating the rotary drum. A rotary head of a magnetic recording and reproducing device, characterized in that fixed sides of the motor and pulse generator are both fixed directly to the fixed drum, and rotating sides of the motor and pulse generator are both fixed directly to the rotating drum. assembly.