JPS637946Y2 - - Google Patents

Description

[Detailed Description of the Invention] The present invention relates to a magnetic head device that is capable of switching the track position of a magnetic tape, and in particular, reciprocating recording and playback in which the track position of a magnetic tape is switched in the forward and reverse directions by rotating the magnetic head. The present invention relates to a magnetic head device for a tape recorder.

Conventionally, the track position of a magnetic tape has been switched when the magnetic tape is driven in the same direction, such as in an 8-track endless playback device or a 4-channel recording/playback device, or in a tape recorder capable of reciprocating recording and playback. There are cases where the magnetic tape is switched between the magnetic tape direction and the reverse direction.As for the means for switching the track position of the magnetic tape, there is a method of switching the magnetic heads using a plurality of magnetic heads with different track arrangements, and a method of switching the magnetic heads using all the required tracks. There may be a method of switching the track connection of the magnetic head using a single magnetic head having a magnetic head, or a method of moving a magnetic head having the minimum number of tracks up and down. The above method is not suitable for tape recorders capable of reciprocating recording and playback with forward and reverse directions in terms of azimuth adjustment and magnetic head adjustment, and further methods require an increase in the number of magnetic heads, resulting in high costs. Besides,
Because the sliding surface of the magnetic tape increases, the running load of the magnetic tape becomes heavy, leading to deterioration of wow and flutter.With method (2), crosstalk increases due to dimensional constraints within the magnetic head, and with method (2), mechanical precision cannot be achieved. It has various drawbacks. In order to eliminate these drawbacks, a method is known in which a single magnetic head is used and the magnetic head is rotated each time the track position is changed, as shown in FIG. That is, the tape recorder shown in FIG. 1 is applied to a cassette tape recorder, and has two
A head support base 2 on which a magnetic head 10 having a magnetic core of a channel (track) is mounted and fixed is pivotally supported on a head rotation shaft 4, and a driven gear 5 for rotating the head is mounted on a drive gear such as a drive gear pivoted on a motor. It is meshed with a drive means (not shown), and a head rotating shaft 4 is fitted and fixed in the center hole of the driven gear 5. Further, the head support base 2 is provided with a rotating arm 3, which is configured to be rotatable together with the head rotation shaft 4. By rotating the drive means in conjunction with track position switching, the head rotating shaft 4 is rotated and the magnetic head 10 is rotated 180 degrees. A head rotation shaft support 6 that supports the head rotation shaft 4 is fixed to a head slide plate (not shown), and azimuth adjustment screws 7a and 7b are provided at both ends via springs.
The position of the rotary arm 3 is regulated by a and 7b, allowing azimuth adjustment in the forward and reverse directions, respectively. Azimuth adjustment screw 7a,
By rotating the magnetic head 7b, it is possible to obtain the best contact angle between the tape and the magnetic head, the so-called azimuth angle.

By rotating the magnetic head 180 degrees in this way, it is possible to record and play back from forward to backward or from backward to forward, and the advantage is that the operation of reversing the tape cassette can be omitted, and a normal stereo magnetic head can be used. It has the following.

By the way, the conventional method of rotating the magnetic head by supporting the head support base on the head rotation shaft from the rear end of the magnetic head and supporting the driven gear at the other end of the head rotation shaft has a structure. The upper depth dimension, that is, the distance 1 from the front surface of the magnetic head to the driven gear, is inevitably large, and it cannot be applied to recent small cassette decks or thin cassette decks, and has a major drawback.

In addition, in such a configuration in which the magnetic head is rotated, when the position of the rotating arm of the head support is regulated by the azimuth adjustment screw, a means for holding (locking) the head support in that state is required.
For this reason, conventionally a reversing spring was applied to the head rotation axis.
The rotating arm was configured to be energized by the azimuth adjustment screw in either direction. However, the method using a spring substantially increases the distance 1 from the front surface of the magnetic head to the driven gear as described above, and also has poor workability during assembly, causing an increase in costs.

The present invention has been made in view of these conventional drawbacks, and its purpose is to extremely reduce the depth dimension in this type of magnetic head rotation mechanism, and to stably and reliably switch the rotation of the magnetic head. To provide a magnetic head device which is easy to operate and has a simple structure without unnecessarily increasing the number of parts.

The following is a description based on embodiments of the present invention.

2 to 4 are diagrams showing an embodiment of the present invention. In the figures, 10 is a magnetic head for recording and playback, and 20 is a magnetic head 10 approximately in the center.
It is a head support stand having a cylindrical outer shape with a head storage part 21 for storing the head, and a flange 22 at both ends, and a driven gear 23 is formed on the circumference on one side of the flange 22. head support stand 2
A rotary arm 24 is provided protruding from the end of the 0. A housing 30 holds the head support 20 on its outer surface, and is composed of an upper housing 31 and a lower housing 32 having approximately semicircular side surfaces. The upper housing 31 has an escape slit 33 so that the driven gear 23 of the head support 20 can rotate, and the slit 3
A tap is formed in the thickness direction of the rear surface 34 formed by 3 so that a pair of screws can be screwed together. and a pair of collar portions 22 including a driven gear 23;
The head rotating support base having the rotating arm 24 and the upper and lower housings 31, 32 are made of a non-magnetic material such as synthetic resin or zinc alloy and are molded as a pair. Azimuth adjustment screws 40A and 40B are screwed into a pair of taps formed on the rear surface 34 of the upper housing 31 via a spring 41, and when the rotary arm 24 comes into contact with the screws, the rotational position of the head support 20 is adjusted. configured to regulate

FIG. 5 also shows magnetic attraction and holding means 50 formed and arranged on the head support 20 and the housing 30. 51 and the upper housing 3 of the housing 30
The magnet 51 and the magnetic material 52 are arranged to face each other as the head support base 20 rotates.

The magnetic head device constituted by the above-mentioned members includes the lower housing 32 of the housing 30.
A driven gear 2 is fixed to a head slide plate (not shown), and a head support 20 housing the magnetic head 10 is meshingly connected to a driving means (not shown).
4, it is configured to be rotatable about a substantially cylindrical shaft.

The driving means for driving the driven gear 23 of the head support base 20 includes, for example, a mechanism in which a slider (rack) meshed with the driven gear 23 is slid by a plunger, or a gear provided on the shaft of a motor. Various mechanisms and methods can be used, such as a mechanism in which the driven gear 24 is rotationally driven.

Next, the rotational operation of the magnetic head device described above is performed in a fifth manner.
To explain with the drawings, first, in the forward state, the magnetic head 10 rotates the driven gear 23 by the meshing connection of the driving means, and the driven gear 23 rotates the head support 20. When the is rotated to a certain extent, the attraction and holding means 50 consisting of the magnet 51 and the magnetic material 52,
The rotating arm 24 of the head support stand 20 is brought into contact with the tip of one of the azimuth adjustment screws 40A, and the rotational position of the head support stand 20 is regulated, so that the magnetic head is held at the track position with respect to the forward direction.
In addition, in this forward state, turn the azimuth adjustment screw 40.
By adjusting A, the azimuth relative to the magnetic tape (not shown) can be easily adjusted by rotating the head support base 20 on which the magnetic head 10 is placed.

Next, switching from the forward state to the reverse state is achieved by moving the drive means in the opposite direction to that in the forward state. The rotary arm 24 is brought into contact with the tip of the other azimuth adjustment screw 40B, and the housing 3 is held by the suction holding means 50.
This is done by holding the head support base 20 relative to 0. By adjusting the azimuth adjustment screw 40B in this reverse state, the head support base 20 on which the magnetic head 10 is housed can be rotated to adjust the azimuth relative to the magnetic tape (not shown).

FIG. 6 is an enlarged view of the circular frame in FIG. 5C, showing the action of the suction holding means 50 which is held using magnets 51 attached to both ends.

In addition, in the above-mentioned embodiment, the rotary arm 24
A magnet 51 is placed on the side, and the housing 31 is
Although the magnetic material 52 is arranged on each side, these may be in the opposite relationship, and the upper housing 31 made of a magnetic material or the azimuth adjustment is placed at a position facing the magnet 51 provided on the rotating arm 24. If the screws 40A and 40B are arranged, the magnetic material 52 is not necessary and can be omitted. Further, it is preferable that the magnet 51 and the magnetic material 52 of the attraction/holding means 50 are constructed so as to form some gap as in the above embodiment when the magnetic head is regulated at the switching position. This is because the magnetic head can be made rotatable with a small driving force when switched in the opposite direction.

Further, although the housing for holding the head support is used as a pair of upper and lower housings, it is possible to use a single housing. In other words, in this case, it is necessary to divide the head support into a plurality of parts so that they can be assembled later, such as by dividing one of the flanges formed at both ends of the head support and assembling them. be.

As explained above, the present invention includes a head support base that accommodates a magnetic head in the axial direction on a substantially cylindrical surface and is provided with a driven gear and a rotary arm, and a housing that holds the head support base. The head support base is rotated about a substantially cylindrical shaft by a driving means meshingly connected to the driven gear, and as the rotary arm rotates, the rotational position is regulated by the housing, and the rotational position of the head support is regulated by the housing. Since it is configured to be held by a magnetic adsorption holding means placed on the housing, the distance from the front surface of the magnetic head to the magnetic head rotation mechanism can be extremely shortened, and its holding can be made extremely simple. It is possible to create a magnetic head device including a magnetic head rotation mechanism that allows the rotation of the magnetic head.

[Brief explanation of the drawing]

FIG. 1 shows a front, top, and side view of a conventional magnetic head device, FIGS. 2 to 6 show an embodiment of the present invention, and FIGS. 3 is a sectional view taken along line A-A' in FIG. 2b, FIG. 4 is an exploded view, FIG.
The figure is an enlarged view of the circular frame portion of FIG. 5c. 10... Magnetic head, 20... Head support stand,
23... Driven gear, 24... Rotating arm, 30... Housing, 50... Suction holding means.

Claims (1)

[Claims for Utility Model Registration] A magnetic head and a head housing portion for housing the magnetic head in the axial direction of the center, a driven gear on the outer periphery, and a rotating arm on one end surface. a cylindrical head support base; the head support base is rotatably held on its outer peripheral surface; and each time the head support base rotates approximately 180 degrees, the rotating arm comes into contact with the head support base to prevent rotation of the head support base; 1. A magnetic head device for a tape recorder, comprising: a housing in which a means for regulating the position is formed; and a magnetic adsorption/holding means disposed on the rotary arm and the housing.