JPS629515A - Rotary automatic reverse head - Google Patents

Abstract

PURPOSE:To facilitate relative alignment between a rotary shaft and a magnetic head by forming a fitting projection and a fitting recessed part having a circular fitting face concentric to the turning center of a magnetic head and a turning shaft to a mutual contact face between a mount member and a fitting plate. CONSTITUTION:The magnetic head 10 is fitted to the fitting plate 4 so that the center shaft of the fitting part 41 and the turning center of the magnetic head 10 are coincident. Then the fitting plate 4 is opposed to the mount member 2 so that screw holes 3a, 3b and through holes 3c, 3d are made coincident and the fitting recess 21 of the mount member 2 and the fitting projection 41 of the fitting plate 4 are fitted. Then screws 5a, 5b are screwed to the screw holes 3a, 3b through the through holes 3c, 3d to fix incorporatedly the mount member 2 and the fitting plate 4. In a head 200 assembled in this way, the alignment accuracy of the magnetic head 10 to the turning shaft 1 is obtained with high accuracy in response to the roundness of the inner circumferential face of the fitting recess 21 of the mount member 2 to the turning shaft 1 and the roundness of the outer circumferential face of the fitting projection 41 of the fitting plate 4 to the turning center of the magnetic head 10.

Description

DETAILED DESCRIPTION OF THE INVENTION (Field of Industrial Application) The present invention relates to a rotary auto-reverse head, and more particularly to a rotary auto-reverse head used in a magnetic recording/reproducing device such as a cassette tape recorder.

[Conventional technology]

FIGS. 4 and 5 are an exploded perspective view and a sectional view showing an example of a conventional rotary auto-reverse head. This rotary auto-reverse head 100 is a disc that is rotatably driven around a rotating shaft 11 and has two protrusions 13a and 13b protruding from its surface (right side in the figure) at predetermined positions with respect to the rotating shaft 11. a mount member 12 shaped like
Hole 15a into which the projections 13a and 13b are fitted
, a mounting plate 14 with holes 15b drilled on the back side, a magnetic head 20 disposed to fit into a mounting hole 14a provided through the mounting plate 14, and a mounting plate 14 mounted on the mounting plate 14. A screw 16a that is integrally screwed onto the member 12,
16b.

Mount members 12 are attached to the projections 13a and 13b.
Threaded holes 17a and 17b into which screws 16a and 16b are screwed are provided so as to pass through them. On the other hand, the hole portion 15a.

15b has a screw 16a extending through the mounting plate 14.

Through holes 17c and 17d are formed through which the cylindrical member 16b is inserted.

Rotary auto-reverse head 1 having such a configuration
To assemble 00, first, assemble the protrusion 17a.

Mounting plate 14 with magnetic helad 20 attached is attached to mounting member 1 so that 17b and holes 15a and 15b are aligned.
2, and fit the holes 15a, 15b of the mounting plate 14 into the projections 13a, 13b of the mount member 12. Next, screw the screws 16a, 16b into the through holes 17c, 1.
7d and screwed into the screw holes 17a and 17b to integrally fix the mounting plate 14 to the mount member 12.

[Problem that the invention seeks to solve]

By the way, since the rotary auto-reverse head is rotated around the rotating shaft 11 when the cassette tape is reversed, in the manufacturing process, the magnetic head 20 is accurately mounted on the mounting plate 14, and the magnetic head 20 is mounted on the mounting plate 14. It is necessary to assemble the rotating shaft 11 and the magnetic head 20 within a predetermined positional accuracy by accurately attaching the magnetic head 20 to the mount member 12, and to eliminate in advance any displacement of the magnetic head 20 due to rotation.

However, the conventional rotary auto reverse
0, the positional accuracy of the magnetic head 20 with respect to the rotating shaft 11 is determined from the rotating shaft 11 to the protrusion 13a of the mount member 12.
, dimensional accuracy up to 13b and hole portions 15a, 15b
It is specified by various precisions such as the mounting precision of the magnetic head 20 relative to the magnetic head 20. For this reason, each precision must be extremely accurate, but from the rotating shaft 11 to the protrusion 13a,
It is not easy to accurately achieve the dimensional accuracy up to 13b, the mounting accuracy of the magnetic head 20 to the holes 15a and 15b, etc., and it is extremely difficult to obtain the rotary auto-reverse head 100 with the required positional accuracy of the magnetic head 20. The problem was that it was difficult.

SUMMARY OF THE INVENTION An object of the present invention is to provide a rotary auto-reverse head that can easily improve the alignment accuracy of a magnetic head with respect to a rotating shaft.

[Means for solving problems]

The rotary auto-reverse head of the present invention is a rotary auto-reverse head in which a mounting plate on which a magnetic head is attached is fixed to a mount member that is rotationally driven around a rotation axis, and the contact surface of the mount member and the mounting plate is provided. A fitting protrusion and a fitting recess formed to have a circular fitting surface concentrically with the rotating shaft and the rotation center of the magnetic head are fitted into the fitting protrusion and the fitting recess. Let me,
It has screws for fixing the integrated mount member and the mounting plate.

[Effect]

In the rotary auto-reverse head of the present invention, a fitting convex portion and a fitting concave portion having circular fitting surfaces are formed concentrically with the rotating shaft and the rotation center of the magnetic head on the mating surfaces of the mount member and the mounting plate. Since the fitting protrusion and the fitting recess are fitted, relative positioning between the rotating shaft and the magnetic head can be performed relatively easily and with high precision.

〔Example〕

FIGS. 1 and 2 are an exploded perspective view and a cross-sectional view of a rotary auto-reverse head according to an embodiment of the present invention. The rotary auto-reverse head 200 of this embodiment is a disc that is rotatably driven around a rotating shaft 1 and is provided with a fitting recess 21 having an inner peripheral surface formed concentrically with the rotating shaft 1 on the contact surface. A fitting convex portion 41 having an outer circumferential surface formed concentrically with the rotation center of the magnetic head 10 to which the magnetic head 10 is attached to the front surface and fitted into the fitting recess 21 is provided. the mounting plate 4, the magnetic head 10 fitted into the mounting hole 4a of the mounting plate 4, and screws 5a for fixing the mounting member 12 and the mounting plate 4 together.

5b.

The mount member 2 has threaded holes 3a and 3b into which screws 5a and 5b are screwed so as to pass through the mount member 2. On the other hand, the mounting plate 4 is provided with through holes 3c and 3d through which screws 5a and 5b are inserted. In addition, in this embodiment, screws 5a, 5b, screw holes 3a, 3
Although one pair of through holes 3c and 3d are provided, the number is not limited to two and can be increased to any number as needed.

To assemble the rotary auto-reverse head 200 having such a configuration, first, attach the magnetic head 10 to the mounting Fi 4 so that the central axis of the fitting convex portion 41 and the rotation center of the magnetic helad 10 coincide with each other. , the mounting plate 4 is opposed to the mount member 2 so that the screw holes 3a, 3b and the through holes 3c, 3d are aligned, and then the fitting recess 21 of the mount member 2 and the fitting protrusion 41 of the mounting plate 4 are aligned. Next, the screws 5a and 5b are passed through the through holes 3c and 3d and screwed into the screw holes 3a and 3b to fix the mount member 2 and the mounting plate 4 together.

In the rotary auto-reverse head 200 assembled in this way, the magnetic head 10 is
The positional accuracy depends on the roundness of the inner peripheral surface of the fitting recess 21 of the mount member 2 with respect to the rotating shaft 1 and the roundness of the outer peripheral surface of the fitting protrusion 41 of the mounting plate 4 with respect to the rotation center of the magnetic head 10. Accordingly, extremely high precision can be obtained. That is, as in the prior art, the protrusions 13a, 13b and the hole 15a,
15b, the outer circumferential surface of the fitting protrusion 41 and the inner circumferential surface of the fitting protrusion 21 are aligned with respect to the rotation center of the rotating shaft 1 and the magnetic head 20, as in this embodiment. This is much easier and results in higher alignment accuracy.

FIG. 3 is an exploded sectional view showing a rotary auto-reverse head 300 according to another embodiment of the present invention. A disc-shaped mount member 20 serving as the fitting convex portion 31 and a fitting recess 71 having a circular inner circumferential surface to which the magnetic head 30 is attached to the front surface and fitted to the fitting convex portion 31 are formed. The magnetic head 30 is fitted into the mounting hole 40a provided through the mounting plate 40, and the screws 51a and 51b are used to integrally screw the mounting plate 40 onto the mounting member 20. configured.

In the rotary auto-reverse head of this embodiment as well, the fitting convex portion 31 of the mount member 20 and the fitting convex portion 71 of the mounting plate 40 are similar to the embodiments shown in FIGS.
and screws 51a, 51b into through holes 23c,
23d and screwed into the threaded holes 23a and 23b, the mount member 20 and the mounting plate 40 are fixed together to form a desired rotary auto-reverse head 300.

Also in the case of this embodiment, the positional accuracy of the magnetic head 30 with respect to the rotating shaft 22 is as follows:
Since it is defined by the roundness of the fitting recess 71 with respect to the rotation center of the magnetic head 30, high positioning accuracy can be obtained relatively easily.

〔Effect of the invention〕

As described above, according to the rotary auto-reverse head of the present invention, it is possible to relatively easily obtain high positioning accuracy of the magnetic head with respect to the rotating shaft, so the assembly accuracy of the rotary auto-reverse head is increased. This has the effect of reducing variations in finished products.

[Brief explanation of the drawing]

FIG. 1 is an exploded perspective view showing a rotary auto-reverse head according to an embodiment of the present invention, FIG. 2 is an exploded sectional view of the rotary auto-reverse head shown in FIG. 1, and FIG. 4 and 5 are exploded cross-sectional views showing a rotary auto-reverse head according to another embodiment of the invention,
FIG. 1 is an exploded perspective view and a sectional view showing an example of a conventional rotary auto-reverse head. In the figure, 1.22...Rotating shaft, 2.20...Mount member, 3a, 3b
, 23a, 23b...screw hole, 3c, 3d,
23c, 23d...-through hole, 4.40...
...Mounting plate, 5a, 5b, 51a, 51b...screw, 10,
30...Magnetic head, 21, 71...
. . . Fitting concave portion, 31, 41 . . . Fitting convex portion. Figure 1 Figure 2 @ Figure 3

Claims (1)

[Scope of Claims] A rotary auto-reverse head in which a mounting plate to which a magnetic head is attached is fixed to a mount member that is rotationally driven around a rotation axis, wherein the rotation axis is attached to a mutually contacting surface of the mount member and the mounting plate. and a fitting protrusion and a fitting recess formed to have a circular fitting surface concentrically with the rotation center of the magnetic head;
A rotary auto-reverse head comprising a screw for fixing the mounting member and the mounting plate, which are integrated by fitting the fitting protrusion and the fitting recess.