JPH0416249Y2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a magnetic head fixing device, and more particularly, to a magnetic head fixing device suitable for a magnetic head reversing device for automatically switching the reproduction direction of a magnetic tape.

Conventionally, when playing back a magnetic tape in a tape recorder, it was common for an operator to reverse the cassette tape according to the direction of playback to obtain the desired playback signal. Auto-reverse type tape recorders and tape players have been put into practical use.

When switching the reproduction direction of a magnetic tape in this type of tape recorder, etc., a magnetic head reversal device is required because one magnetic head is reversed to switch the reproduction direction. Conventional magnetic head reversing devices have a complicated structure, and in order to maintain a certain level of accuracy, a radial bearing is used for the rotating shaft, which has the drawback of increasing the price.

Therefore, we simplified the structure of the bearing part and
A reversing device for a magnetic head has been proposed that can prevent rattling due to wear, obtain a stable reversing state, and is miniaturized.

The object of this invention is to provide a magnetic head fixing device that simplifies the fixing structure of the magnetic head in a magnetic head reversing device, prevents positional shift, etc., and provides a stable fixed state.

The object of this invention is to provide a fixing device for a magnetic head that can rotatably fix the magnetic head, has a simplified fixing structure, prevents displacement of the magnetic head, and realizes a stable fixed state.

That is, in the magnetic head fixing device of this invention, a first rotary support part 14 having a cylindrical shape is formed, a through hole 18 is formed in the first rotary support part, and a first rotary support part 18 is formed on the inner surface of the through hole. A fixed frame 2 has a rotating support surface 22 formed thereon, a magnetic head 10 is attached to the top surface, and a support shaft 20 passes through the through hole in the back surface.
A second rotary support part 32 that is protrudingly provided, has an annular shape into which the first rotary support part is fitted around the support shaft, and has a second rotary support surface 34.
is formed, and the first ball 30 inserted between the peripheral surface of the support shaft and the first rotation support surface is held by the support ring 24 attached to the support shaft, and the first ball 30 is held by the support ring 24 attached to the support shaft. A movable frame 8 is rotatably attached to the fixed frame by inserting a plurality of second balls 36 between the peripheral wall surface of the rotation support part and the second rotation support surface 34. It is characterized by

Hereinafter, this invention will be described in detail with reference to embodiments shown in the drawings.

1 to 4 show an embodiment of the magnetic head fixing device of this invention, FIG. 1 is a partially cutaway side view showing the reversing mechanism of the magnetic head, FIG. 2 is a plan view thereof, and FIG. 4 shows an exploded perspective view of the movable frame, the holding frame, and the leaf spring portion, and FIG. 4 shows a sectional view showing the fixing structure of the holding frame.

In FIG. 1, a fixed frame 2 is fixed to the frame of a tape recorder through mounting holes 4 and 6 formed on both sides. A movable frame 8 is rotatably supported at the center of the fixed frame 2, and a holding frame 12 for holding a magnetic head 10 is detachably fixed to the movable frame 8.

In the center of the fixed frame 2, a first rotary support part 14 having a cylindrical shape is provided to rotatably support the movable frame 8.
A recess 16 having a U-shaped cross section is formed around the rotation support portion 14 . A support shaft 20 provided at the center of the movable frame 8 is inserted into the through hole 18 formed at the center of the rotation support part 14, and a conical surface forming an angle of 45° is formed on the inner wall thereof. A first rotation support surface 22 is formed. This rotary support surface 22 is closed by a support ring 24 fixed to the support shaft 20, and this support ring 24 is fixed by a gear 28 via a spring 26. The spring 26 has a disc shape,
It is made by bending it into an S-shape to give it elasticity. A plurality of balls 30 are installed between the support ring 24 and the support shaft 20, and the support shaft 18 is rotatably supported on the rotation support surface 22 of the fixed frame 2 via the plurality of first balls 30. . Furthermore, inside the rotation support part 32 of the movable frame 8 facing the recess 16 of the fixed frame 2, a second conical surface of 45° is provided.
A rotation support surface 34 is formed, and this rotation support surface 3
4 and the outer periphery of the rotation support part 14 of the fixed frame 2 and the inner bottom surface of the recess 16 are provided with a plurality of second balls 3.
6 is installed, and a rotary support portion 32 of a movable frame 8 is rotatably supported by the fixed frame 2.

Further, the fixed frame 2 is provided with stopper screws 38 and 40 for preventing the rotation of the movable frame 8, as shown in FIG.
It is fixed by interposing a coil spring 42, and its tip portion faces within the rotation range of the movable frame 8. On the other hand, a locking protrusion 44 is protruded from the side of the movable frame 8, and the abutment screws 46A, 46 are provided at the abutting portions.
B is fixed.

A fixed protrusion 48 located on the front side of the holding frame 12 is protruded from the upper surface of the movable frame 8, and a pair of fixed protrusions 50A and 50B facing the sides of the holding frame 12 are protruded. and the fixed protrusions 50A, 5
A notch 52 is formed between 0B. A position adjustment screw 54 is attached to the screw hole 49 formed in the fixed protrusion 48 , the front part of the holding frame 12 is brought into contact with the tip of this position adjustment screw 54 , and its position is adjusted by the position adjustment screw 54 . is made possible. A U-shaped recess 56 is formed at the bottom of these fixing projections 50A, 50B, and a pair of engaging projections 58A, 58B are inserted into the recess 56 on both sides of the holding frame 12.
is formed with a notch 60.

Further, a rectangular protrusion 64 for fixing a leaf spring 62 for fixing the holding frame 12 is formed on the upper surface of the movable frame 8, and an engagement hole 65 is formed in the fixed protrusion 64. The engagement hole 65 has a large front opening and a step 67 in the middle to make the rear part narrower.

As shown in FIG. 3, the leaf spring 62 has a rectangular through hole 66 formed in the center and a bent part 70 bent into a box shape. An L-shaped engaging tongue piece 68 is formed to be inserted into and engaged with the matching hole 65, and a pressing part 72 is further formed at the rear edge of the bent part 70. Pressing part 7
2 is formed with a support portion 74 that is bent at a substantially right angle and stands up at the rear edge of the bent portion 70.
Fold the middle part of 4 downward into a V-shape, and attach the holding frame 1.
A contact piece 76 is formed that comes into contact with the rear surface portion of 2.

With the above structure, the fixed protrusion 64 is inserted into the through hole 66 of the leaf spring 62 and fixedly placed on the upper surface of the movable frame 8. In this case, the locking tongue piece 68 of the leaf spring 62 is inserted into the engagement hole 65 of the fixed protrusion 48 and locked therein. Then, the rear part of the holding frame 12 to which the magnetic head 10 is attached in advance is attached to the abutting piece 76 of the leaf spring 62.
, the holding frame 12 and the leaf spring 62 are tilted backward, and the engaging protrusions 50A and 50B of the holding frame 12 are inserted into the recess 56 of the movable frame 8. In this case, the holding frame 12 slides forward by the biasing force of the abutment piece 76 of the leaf spring 62, and its front part abuts the end of the position adjustment screw 54 fixed to the fixing protrusion 48, fixing the position. At the same time, as shown in FIG. 4, the movable frame 8
A holding frame 12 is firmly fixed on top.

Since the movable frame 8 is rotatably supported by the fixed frame 2, the gear 28 at the rear end of the support shaft 20
A rotary drive mechanism such as a magnetic solenoid that responds to the direction of playback of the magnetic tape (not shown) is connected to the frame 8, and the movable frame 8 is rotated in the direction shown by the arrow A-B in FIG. It can be reversed depending on the playback direction. FIG. 2 shows a state in which the magnetic head 10 has been displaced by about 10 degrees in the direction of arrow B. As shown in FIG. In this case, the rotation start point and end point can be adjusted by adjusting the amount of protrusion of the stopper screws 38, 40.

According to such a configuration, the magnetic head 10 can be fixed in advance to the holding frame 12 and fixed to the movable frame 8 via the holding frame 12, and the rotation mechanism for fixing the magnetic head 10 and rotating the movable frame 8 is combined. Since the magnetic head 1 can be constructed separately and assembled separately, the rotation accuracy of the rotation mechanism can be improved, and the magnetic head 1 can be assembled separately.
Adjustment of the 0 position etc. can be performed precisely. Further, since the holding frame 12 to which the magnetic head 10 is attached can be detachably attached to the movable frame 8 and firmly fixed, the influence of positional shift etc. on the reproduced sound can be suppressed. Moreover, the vertical position of the magnetic head 10, that is, the deviation of the contact surface of the magnetic tape, can be adjusted by adjusting the protrusion amount of the position adjustment screw 54 and moving the holding frame 12 against the pressing part 72 of the leaf spring 62. Can be adjusted. In this case, since the holding frame 12 can be slid on the upper surface of the movable frame 8, precise adjustment is possible, and since it is not necessary to remove the magnetic head 10 or the holding frame 12, the adjustment work is facilitated.

As explained above, according to this invention, the magnetic head can be fixed in a reversible manner, and the fixing structure of the magnetic head can be simplified, and its installation and position can be easily adjusted, thereby preventing misalignment, etc. can be prevented and a stable fixation state can be obtained.

[Brief explanation of the drawing]

Fig. 1 is a partially cutaway side view showing an embodiment of the magnetic head fixing device of this invention, Fig. 2 is a plan view thereof, and Fig. 3 is an exploded perspective view showing the structure of the movable frame, holding frame, and leaf spring. 4 are sectional views showing the fixing structure of the holding frame. 2... Fixed frame, 8... Movable frame, 10... Magnetic head, 14... First rotation support part, 18... Through hole, 20... Support shaft, 22... First rotation support surface, 24...Support ring, 30...First ball, 32...Second rotation support part, 34...Second rotation support surface, 36...Second ball.

Claims (1)

[Claims for Utility Model Registration] A cylindrical first rotation support part is formed, a through hole is formed in the first rotation support part, and a first rotation support surface is formed on the inner surface of the through hole. A fixed frame is formed, a magnetic head is attached to the upper surface part, a support shaft is protruded from the back surface thereof passing through the through hole, and the first rotary support part is fitted into a circle around the support shaft. A second rotational support part is formed in an annular shape and has a second rotational support surface, and the first ball is inserted between the peripheral surface of the support shaft and the first rotational support surface. The second balls are held by a support ring attached to the support shaft, and a plurality of second balls are inserted between the peripheral wall surface of the first rotation support part and the second rotation support surface. A magnetic head fixing device comprising: a movable frame rotatably attached to a fixed frame;