JPS639861Y2 - - 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 is capable of reciprocating recording and playback by switching the track position of the magnetic tape by rotating the magnetic head, sometimes in the forward and reverse directions. 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 a tape recorder capable of reciprocating recording and playback with forward and reverse directions in terms of adjusting the magnetic head due to azimuth adjustment, etc. Furthermore, method 1 requires an increase in the number of magnetic heads, resulting in high cost. In addition, since the sliding surface of the magnetic tape increases, the magnetic tape running load becomes heavy, leading to deterioration of wow and flutter.Method 2 increases crosstalk due to dimensional constraints within the magnetic head, and method 3 increases It has various drawbacks such as lack of mechanical precision. In order to eliminate such 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 the first article. That is, the tape recorder shown in FIG. 1 is applied to a cassette tape recorder, in which a head support 2 on which a magnetic head 10 having a two-channel (track) magnetic core is mounted and fixed is attached to a head rotating shaft 4. A driven gear 5 for rotating the head is in mesh with a driving means (not shown) such as a driving gear pivotally connected to a motor.
A head rotating shaft 4 is fitted and fixed in the center hole of the head. Further, the head support base 2 is provided with a rotating arm 3, which is configured to be rotatable together with the head rotating 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. The head rotation shaft support base 6 that supports the head rotation shaft 4 is a head slide plate (not shown).
Azimuth adjustment screws 7a, 7b are provided at both ends via springs, and the adjustment screws 7a, 7b are fixed to
The position of the rotary arm 3 is regulated by 7b, and the azimuth can be adjusted in the forward direction and the reverse direction, respectively. By rotating the azimuth adjustment screws 7a and 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 from the rear end of the magnetic head with a head rotating shaft and supporting a driven gear at the other end of the head rotating shaft is based on the track position. When regulating the position of the magnetic head related to switching, the driving means meshingly connected to the driven gear must always be driven in one direction, requiring mechanical precision of the driving means with respect to the driven gear, and due to its structure. Since the depth dimension, ie, the distance l from the front surface of the magnetic head to the driven gear, is inevitably large, it cannot be applied to recent small cassette decks or thin cassette decks, and has a major drawback.

The present invention was developed in view of these conventional drawbacks, and its purpose is to minimize the depth dimension of this type of magnetic head rotation mechanism and to create a structure without increasing the number of parts unnecessarily. An object of the present invention is to provide a simple magnetic head device capable of stably holding a magnetic head at a predetermined regulated position.

Hereinafter, the present invention will be explained based on examples.

2 to 5 are diagrams showing one 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 collar part 22 at both ends, and a driven gear 23 is formed on the circumference of the center part. A rotating arm 24 is provided protruding from the end of the head support base 20. 3
A housing 0 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 head support base 2 is attached to the upper housing 31.
It has a rear surface 33 that protrudes so that the driven gear 23 of No. 0 can rotate, a shaft 34 is formed on this rear surface 34, and a pair of screws are screwed together in the thickness direction of the rear surface 33. A tap is formed. The collar portion 22 including the driven gear 23, the head rotation support base having the rotating arm 24, and the upper and lower housings 31 and 32 are made of non-magnetic material such as synthetic resin or zinc alloy and are integrally molded. 40A and 40B are springs 41 and 40B attached to a pair of taps formed on the rear surface 34 of the upper housing 31;
This is an azimuth adjustment screw that is screwed together via the head support 42, and is configured so that the rotary arm 24 comes into contact with it to define the rotational position of the head support base 20. 50, as shown in FIGS. 3 and 4, a shaft hole 51 that engages with the shaft 34, and a tooth portion 52 that meshes with the driven gear 23.
and a drive gear integrally formed with a protrusion 53 at the end thereof, and is connected to the upper housing 31 by the shaft 34.
is rotatably fixed. Note that the drive gear 50
Like the housing 30, it is preferable that the housing is made of a material such as synthetic resin or zinc alloy.
Reference numeral 60 is composed of a movable core wire (wire body) 61, a pair of regulating pieces 62A, 62B formed at one end of the core wire 61, and a sheath 63 covering the core wire 61, and is a wire means represented by a release. The other end of the core wire 61 is the drive gear 50
One end of the outer cover 63 is fixed to the housing 30, and the other end is fixed to a fixing member (not shown) such as a chassis. The wire means rotates the driving gear 50 by moving the core wire 61. 70
5 is a wire driving means mounted on a fixed member (not shown) such as a chassis, and as shown in FIG. It is composed of a spring 72 that biases regulating pieces 62A and 62B formed at one end of 61 in opposite directions.
The holder 71 is moved by a predetermined stroke A as shown by the dotted line in FIG. 2 by a sliding means (not shown),
The core wire 61 of the wire means 60 is moved in one direction via a spring 72.

In addition to the sliding means described above, the means for moving the core wire 61 of the wire means 60 in one direction may be a rotating winding means for winding the core wire 61 around a rotating member. Various mechanistic methods can be used for this purpose.

Next, to explain the rotational operation of the magnetic head device described above, first, in the forward state, although not shown in FIG. When the wire means 60 is moved, the core wire 61 of the wire means 60 is pulled through the spring 72, and the drive gear 50 is rotated counterclockwise about the shaft 34. As the driving gear 50 rotates, its rotational force is transmitted to the driven gear 24, and the driven gear 24 rotates in the same direction as the driving gear 50, which rotates the head support base 20 counterclockwise, and the magnetic head 10 is rotated. The rotary arm 23 of the head support base 20 is brought into contact with the tip of one of the azimuth adjustment screws 40A, and the rotational position of the head support base 20 is regulated, so that the magnetic head is held at the track position with respect to the forward direction. . Note that by adjusting the azimuth adjustment screw 40A in this forward state, the azimuth relative to the magnetic tape (not shown) can be easily adjusted by rotationally adjusting 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 sliding means in the opposite direction to that in the forward state, thereby urging the driven gear 24, which is meshed with the driving gear 50, to rotate in the opposite direction. This is done by abutting the rotating arm 23 of the head support base 20 against the tip of the other azimuth adjustment screw 40B. 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).

In the magnetic head device composed of the above-mentioned members, the lower housing 32 of the housing 30 supports the head slide plate (not shown), and the means (not shown) for moving the wire means 60 supports the head slide plate. A head support 20 housing the magnetic head 10 is rotatable about a substantially cylindrical shaft by a driven gear 24 meshed with a drive gear 60. It is configured as follows.

In the above-described embodiment, the housing for holding the head support is used as a pair of upper and lower housings, but 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 of a substantially cylindrical shape and is formed with a driven gear and a rotary arm, a housing that holds the head support base, and drive means for rotating a drive gear meshingly coupled to a driven gear of the drive gear, the drive means having wire means connected and fixed to an end of the drive gear, and movement of the wire means causes the drive gear to rotate. The head support is rotated about a substantially cylindrical shaft by the rotation of the driven gear meshingly connected to the drive gear, and the rotational position of the rotary arm of the head support is regulated by the housing. Since the rotary head is rotationally driven by a highly flexible wire means, when switching the magnetic head, the head support that houses the magnetic head can be attached in one direction with an extremely simple structure. The position can be regulated while increasing the force, and the azimuth regulation position can be stably maintained even when the azimuth is adjusted.

[Brief explanation of the drawing]

FIG. 1 shows a front, top, and side view of a conventional magnetic head device, FIGS. 2 to 5 show an embodiment of the present invention, and FIG. FIG. 4 is a perspective view of the driving gear, and FIG. 5 is a partially enlarged sectional view of the wire means. 10... Magnetic head, 20... Head support stand,
23... Driven gear, 24... Rotating arm, 30... Housing, 40A, 40B... Azimuth adjustment screw, 50... Drive gear, 60... Wire means,
70...Wire driving means.

Claims (1)

[Claims for Utility Model Registration] A cylindrical head support base having a magnetic head, a head storage part for storing the magnetic head in the axial direction of the center part, and a driven gear and a rotating arm formed on one end surface. and a means for rotatably holding the head support on its outer peripheral surface, and for regulating the rotational position of the head support by coming into contact with the rotary arm each time the head support is rotated approximately 180 degrees. a drive gear that meshes with a driven gear of the head support; and a wire means that is connected and fixed to an end of the drive gear to rotate the drive gear. A magnetic head device for a tape recorder, characterized in that: