JPH03154219A - Rotary magnetic head device - Google Patents

Abstract

PURPOSE:To reduce noise of the device by providing a cover whose surface is smooth while covering the rugged structure of an upper part of a rotary drum to the upper part of the drum and covering the rugged structure of the upper part, thereby reducing wind noise even when a rotary magnetic head device is driven at high speed. CONSTITUTION:A cover 4 is provided to cover the upper part of a drum 1, a thread 1D of the drum and a thread 4A of the cover 4 are screwed to fix the cover 4 to the drum 1. The surface of the cover 4 is finished smoothly without ruggedness and the outer diameter is formed identically to that of the drum 1. Even when a tape is wound onto the drum 1, the tape is not in press contact with the cover 4 to cover a head adjustment hole 1A of the upper face of the drum 1. Then the inner space of the cover 4 and the drum 1 is formed small and when the size of space is large, a silencing member is packed to prevent the resonance. Thus, even when the drum 1 is driven at high speed, sound noise is reduced by reducing the wind noise of the device.

Description

DETAILED DESCRIPTION OF THE INVENTION Field of Industrial Application The present invention relates to a rotating magnetic head device used in video tape recorders (hereinafter referred to as VTRs) and the like.

2. Description of the Related Art In recent years, high-density magnetic recording technology has been developed, and one way to increase the recording density is to increase the rotation speed of a rotating magnetic head device. When the drum is rotated at high speed, the unevenness of the upper part of the drum generates a lot of noise such as wind noise, which is not acceptable for household use. Furthermore, in the conventional rotating head drum electric shield disclosed in Japanese Patent Application Laid-Open No. 57-172528, only the relay wires were covered for the purpose of electric shielding, so it did not contribute to low noise. do not have.

Problems to be Solved by the Invention In such a conventional rotary magnetic head device, there are terminals, a printed circuit board, etc. on the upper part of the rotary magnetic head device, and wind noise increases when the rotary magnetic head device rotates at high speed. Such noise goes against the trend toward higher sound quality in home VTRs in recent years, and has the problem of degrading the quality of the product.

The present invention solves the above-mentioned conventional problems and provides a rotary magnetic head device that produces less noise even when the rotary magnetic head device rotates at high speed.

Means for Solving the Problems In order to achieve the above object, the rotating magnetic head device of the present invention includes a rotating drum on which a magnetic head is mounted and a magnetic head protection hole on the upper surface, and a magnetic tape is wound around the rotating drum. In a rotating magnetic head device in which a magnetic head scans a magnetic tape to record and reproduce signals, a cover with a smooth surface is provided on the top of the rotating drum to cover the irregularities on the top of the rotating drum. be.

By covering the irregularities on the upper part of the operating rotating magnetic head device, wind noise can be reduced, making it possible to create a rotating magnetic head device with less noise.Also, it is possible to securely fix the rotating magnetic head device without loosening even at high rotation speeds.

Example An embodiment of the present invention will be described below.

FIG. 1 is a sectional view of a first embodiment of the invention.

A magnetic head 2 is fixed to the lower surface of the drum 1.

Further, an adjustment hole IA for adjusting the attachment of the magnetic head 2 is provided on the upper surface of the drum l.

Furthermore, there is a relay terminal IB that relays the signal line from the magnetic head 2, and a fixing screw IC that fixes the drum 1 to the lower drum 3.
etc., form unevenness on the upper part of the drum l.

When the drum l rotates at high speed, these irregularities generate wind noise and increase the noise. Therefore, a cover 4 is provided to cover the top of the drum 1. Threaded portion ID provided on the inner peripheral surface of drum l and threaded portion 4A provided on cover 4
By screwing them together, the cover 4 is fixed to the drum 1.

The surface of the cover 4 has a smooth finish with no edges or irregularities. Further, the outer diameter of the cover 4 is made approximately the same as the outer diameter of the drum 1, so that even when the tape is wound around the drum 1, it does not come into contact with the cover 4, and the head adjustment hole on the top surface of the drum 1 is arranged. It is designed to cover the IA. In addition, the internal space between the cover 4 and the drum 1 should be kept as small as possible to prevent resonance, and if the space is large, the space should be filled with a non-conductive sound dampening material (sponge, etc.) to prevent resonance. The aim is to prevent noise and reduce noise.

The cover 4 is fixed to the drum l by screwing the threaded part ID provided on the inner peripheral surface of the drum l and the threaded part 4A provided on the cover 4 in the opposite direction to the rotating direction of the drum 1. It is designed to be fixed.

Furthermore, by molding and using the cover from a conductive material, the influence of external electric fields can be reduced.

Next, a method of fixing the cover of the second embodiment will be explained using FIGS. 2 and 3. FIG. 2 is a cross-sectional view of a second embodiment of the cover, and FIG. 4 is a cross-sectional view of the second embodiment when the cover is secured to the drum.

A spring member 6 is integrally formed in the cover 4,
Rubber 7 is provided at the end of this spring member 6.

When the drum 1 rotates, the rubber 7 is urged in the direction of arrow H by centrifugal force, and the drum 1 and cover 4 are fixed.

DETAILED DESCRIPTION OF THE INVENTION As described above, the rotating magnetic head device of the present invention is equipped with a magnetic head, and a rotating drum is wound with a magnetic tape, and the magnetic head scans the magnetic tape to record and reproduce signals. In a rotating magnetic head device that uses a rotating magnetic head, a cover with a smooth surface that covers the unevenness of the upper part of the drum is installed on the top of the drum. To provide a rotating magnetic head device which reduces wind noise by covering the unevenness of the upper part of the device and has less noise. In addition, by screwing the drum in the opposite direction to the rotating direction of the drum or using a method of fixing using the centrifugal force of rotation, it is possible to securely fix the drum without loosening even at high rotations. can. Furthermore, by molding the cover from a conductive material, it is possible to provide an electrical shielding effect and prevent radio waves from entering the magnetic head, wiring, etc. from the outside.

According to this embodiment, the spring for fixing the cover is separate from the cover, but it may be integrally molded with the cover, or the cover may be molded from a conductive material. ,
If it has an electrical shielding effect, surface treatment such as chrome coating may be applied after molding.

[Brief explanation of the drawing]

FIG. 1 is a sectional view of one embodiment of the present invention, FIG. 2 is an illustration of a second embodiment of the cover fixing part of the present embodiment, and FIG. 3 is a cross-sectional view of the cover in FIG. 2. It is a sectional view showing after fixing to a drum. l...Drum, IA...adjustment hole, IB
...Relay terminal, Ic...Mounting screw, I
D...Screw part, 2...Magnetic head, 3
...Lower drum, 4...Cover 4A...
...Screw part, 5...Sponge, 6...
...Spring, 7...Rubber.

Claims (6)

[Claims] (1) A rotating drum on which a magnetic head is mounted and having adjustment holes on the top surface for adjusting the attachment of the magnetic head; a magnetic tape is wound around the rotating drum; and the magnetic head scans over the magnetic tape. 1. A rotary magnetic head device for recording and reproducing signals using a rotary magnetic head device, characterized in that a cover is provided on the top of the rotary drum, the cover having a smooth surface covering the irregularities on the top of the rotary drum. (2) The rotating magnetic head according to claim (1), wherein the cover has an outer diameter that is substantially the same as the outer diameter of the rotating drum, and covers the magnetic head adjustment hole on the upper surface of the rotating drum. Device. (3) The rotary magnetic head device according to claim 1, wherein at least one of the cover and the drum has an engaging portion that generates an engaging force when the drum rotates. (4) The rotary magnetic head device according to claim (1), wherein the engaging portion between the cover and the drum is fixed by being rotated in a direction opposite to the rotating direction of the drum. (5) The rotary magnetic head device according to claim (1), wherein the cover and the inner space of the drum are filled with a non-conductive sound-deadening member. (6) The rotary magnetic head device according to claim (1), wherein the cover is made of a conductive member.