JPH0536159A - Tape core rotating device - Google Patents

Abstract

(57) [Summary] [Object] The present invention relates to the running of a magnetic tape, and an object thereof is to provide a tape core rotating device that enables stable running of the magnetic tape. In a rotating device having a tape core having an inward protrusion and a rotating shaft for engaging and rotating the tape core, the engaging protrusion abuts the inward protrusion from above and below when viewed in the axial direction of the rotating shaft. Thus, it has an axial positioning portion that fixes the axial position of the inward projection. As a result, the inward projection can be positioned in the axial direction.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a magnetic recording / reproducing device, and more particularly to a tape core rotating device for running a tape.

[0002]

2. Description of the Related Art A conventional magnetic recording / reproducing apparatus using a compact cassette tape will be described with reference to the drawings.

Referring to FIG. 13, the magnetic recording / reproducing apparatus 50 includes a compact cassette tape 51, a magnetic head 56 for recording / reproducing on / from a magnetic tape 57 mounted in the compact cassette tape 51, and the magnetic field. A rotary encoder 55 for detecting the running speed of the tape 57 is provided.

The magnetic tape 57 is wound around a tape core 52 having a central hole in which an inward projection 52a protruding toward the center is formed.

The tape core 52 includes the tape core 52.
A rotary shaft 53 is inserted into a central hole of the tape core rotating device 54, and an engaging projection 53 for rotating the tape core 52 together with the rotary shaft by contacting the inward projection 52a formed on the rotary shaft 53 is provided. It is provided.

In the tape running of the magnetic tape 56, the rotation of the tape core rotating device 54 is transmitted to the tape core 52 via the rotating shaft 53, and the magnetic tape 57 is sent out from one tape core 52 as the tape core 52 rotates, and the other. The tape core 52 is wound up. As a result, the magnetic tape 57 runs on the surface of the magnetic head 56, and recording / reproducing is performed. At this time, the rotary encoder 55 detects the traveling speed of the magnetic tape, the drive voltage of the tape core rotating device 54 is adjusted so that the number of pulses emitted from the rotary encoder 55 becomes a constant value, and the traveling speed of the magnetic tape 57 becomes a constant value. Controlled by.

Next, the compact cassette tape 51 used in the magnetic recording / reproducing apparatus 50 will be described with reference to the drawings.

Referring to FIG. 14, the compact cassette tape 51 comprises a magnetic tape 57, a tape core 52, an upper case 58 and a lower case 59. In the figure, (a) is a top view, (b) is a plan view, (c) is a side view, and (d) is a sectional view taken along the line AA in (b).

The magnetic tape 57 and the tape core 52 are housed in an outer frame formed of an upper case 58 and a lower case 59 with liner sheets 60 and 61 sandwiched therebetween, and the magnetic tape 57 and the tape core are arranged in the width direction and the thickness direction of the magnetic tape. 52 is arranged so as to be movable within a predetermined range.

The tape core 52 is composed of an inward projection 52a protruding toward the center and a ring 52b. A magnetic tape 57 is wound around the ring 52b, and the inward projection 52
A is engaged with the tape core rotating device 54 and is rotatable.

Next, referring to FIGS. 15 and 16, the relationship between the tape core 52 and the tape core rotating device 54 will be described.
The rotary shaft 53 is inserted into the tape core 52, and the arrow A in the figure
When rotating in the direction, the inward projection 52a provided on the tape core 52 and the engagement projection 53 provided on the rotation shaft 53
When a comes into contact with the inward projection 52a, the rotation shaft 53
It is possible to rotate the tape core 52 along with the rotation.

By the rotating operation of the tape core rotating device 54, the magnetic tape 57 travels in a predetermined direction and the magnetic head 56 can reproduce and record.

[0013]

However, in the tape core rotating device having the above structure, the tape core 52 is formed in the compact cassette tape 51 by the upper case 58 and the lower case 59 via the liner sheets 60 and 61. It is sandwiched. Further, a clearance is provided between the tape core 52 and the liner sheets 60 and 61 so that the tape core 52 can rotate.

As shown in FIG. 15 and FIG. 16, the conventional inward projection 52a formed on the tape core 52 has a triangular cross section and has the same cross section with respect to the axial direction and the axial direction. It is parallel and has no inclination. As a result, when vibration is applied to the main body of the magnetic recording device, the tape core 52 vibrates vertically.

This vibration affects the running of the magnetic tape 57, and the information recorded on the magnetic tape 57 at intervals of several hundred μm divided into several tens of tracks is accurately reproduced on each channel of the magnetic head 56. This causes a problem that a good head output cannot be obtained.

The present invention has been made to solve the above problems, and an object of the present invention is to provide a tape core rotating device which does not affect the running of the magnetic tape even with external vibration. ..

[0017]

To rotate a tape core having a central hole in which an inward projection protruding toward the center is formed, the rotary shaft inserted into the central hole, and the rotation shaft. A tape core rotating device, comprising: an engaging protrusion formed on a shaft to rotate the tape core together with the rotating shaft by contacting the inward protrusion.
The engagement protrusion has an axial positioning portion that fixes the axial position of the inward protrusion by contacting the inward protrusion from above and below when viewed in the axial direction of the rotating shaft.

[0018]

Operation: The inward projection provided on the tape core is abutted from above and below when viewed in the axial direction of the rotating shaft, and the engaging projection having the axial positioning portion for fixing the axial position of the inward projection is provided on the rotating shaft. As a result, it is possible to prevent the tape core from vertically vibrating due to external vibration.

[0019]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS A first embodiment based on the present invention will be described below with reference to the drawings. The structures of the magnetic recording / reproducing apparatus and the compact cassette tape used in this embodiment are the same as those of the prior art. Therefore, only the structure of the tape core of the compact cassette tape, the structure of the rotating shaft of the tape core rotating device of the magnetic recording / reproducing apparatus, and their relation will be described here.

First, referring to FIG. 1, the structure of the rotating shaft 3 of the tape core rotating device is shown in FIG.
b and the engaging protrusion 3c.

The main body shaft 3a is fixed to a drive shaft of a drive motor (not shown) and transmits the driving force to the reel table 3b.

The engaging projection 3c has a predetermined uniform thickness, has a substantially rhombic plan shape, and is provided at three circumferentially divided positions.

Next, a state in which the rotary shaft 3 is inserted into the tape core 1 will be described with reference to FIGS. 2 and 3. Figure 2
Shows a front view and FIG. 3 shows a top view.

The center and height position of the tape core 1 are determined by the reel table 3b. First, the centering of the tape core 1 is performed by the inward projection 1a formed on the tape core 1.
The center formed by inserting the rotary shaft 3 into the tape core 1 by the circle formed by the end face 1aa of the tape and the cylindrical surface 3ba of the reel table 3b set to a diameter smaller than the diameter of this circle by several tens (μm). Done.

Next, for the positioning of the tape core 1 in the height direction, the inward projection 1a is the tape surface 3b of the reel table 3b.
Positioning is performed by inserting the tape core 1 into the rotating shaft 3 up to the position where it abuts against b. At this time, the reel table surface 3bb is set so that the tape core 1 is in a position not in contact with either the upper case or the lower case of the compact cassette tape.

Next, the relationship between the inward projection 1a at the tape core position and the engaging projection 3c of the rotary shaft 3 in the rotating state of the rotary shaft 3 will be described with reference to FIG.

When the rotary shaft 3 rotates in the direction of arrow A in the figure, the inward projection 1a is located in the space formed by the reel table surface 3ba and one side 3ca of the engaging projection 3c.

At this time, a predetermined force F acts on the inward projection 1a from one side 3ca of the engaging projection 3c. This force F is shown in FIG.
As shown in FIG. 5, a force F'presses the inward projection 1a against the reel table surface 3ba, and the inward projection 1a is substantially
The reel table surface 3ba and the one side 3ca of the engaging projection 3c are used for positioning.

As a result, even when the rotating shaft 3 vibrates in the axial direction, the inward projection 3c maintains a constant position without being affected by the vibration, that is, the position of the tape core 1 can be stabilized. It will be possible.

In this embodiment, the engaging projections 3 are formed in a substantially rhombic shape so that the rotary shaft 3 can be easily inserted into the tape core 1, and the rotary shaft rotates in the direction of arrow B in FIG. Even in this case, the inward projection 1a is present at the Z position, and the same function and effect as above can be obtained.

Next, a second embodiment based on the present invention will be described with reference to the drawings. It should be noted that this embodiment is based on the first
Since only the shape of the engagement protrusion 3c in the embodiment of FIG.
Only the features of this shape will be mentioned here.

Referring to FIG. 5, the engaging projection 13c in this embodiment has a shape in which a substantially cylindrical tube projects toward the center.

As for the relationship between the engaging projection 13c and the inward projection 1a, referring to FIG. 6, when the rotary shaft 3 rotates in the direction of arrow A in the figure, the inward projection 1a is moved to the reel table surface 3ba.
And is located in the space formed by the contact piece 13ca of the engaging projection 13c.

At this time, the contact piece 13c of the engaging projection 13c
A predetermined force F acts on the inward projection 1a from a. This force F
Is a force F'pressing the inward projection 1a against the reel table surface 3ba as shown in FIG. 6, and the inward projection 1a is substantially positioned by the contact piece 13ca of the reel table surface 3ba and the engaging projection 13c. .

As a result, even when the rotary shaft 3 vibrates in the axial direction, the inward projection 13c maintains a constant position without being affected by the vibration, that is, the position of the tape core 1 can be stabilized. Becomes

In this embodiment, the engaging projection 3 is formed in a cylindrical shape so that the rotary shaft 3 can be easily inserted into the tape core 1, and the rotary shaft rotates in the direction of arrow B in FIG. Even in the case of doing, the inward projection 1a is
This is because it exists at the Z position and the same effect as the above can be obtained.

Next, a third embodiment based on the present invention will be described with reference to the drawings. It should be noted that this embodiment is based on the first
Since only the shape of the engagement protrusion 3c in the embodiment of FIG.
Only the features of this shape will be mentioned here.

Referring to FIG. 7, the engaging projection 23c in this embodiment has a predetermined uniform thickness and has a substantially triangular planar shape.

As for the relationship between the inward projection 1a and the engaging projection 23c, referring to FIG. 8, when the rotary shaft 3 is rotated in the direction of arrow A, the inward projection 1a is one side of the reel table surface 3ba and the engaging projection 23c. It is located in the space formed by 23ca.

At this time, a predetermined force F acts on the inward projection 1a by one side 23ca of the engaging projection 23c.

This force F is applied to the inward projection 1 as shown in FIG.
The force F'presses a against the reel table surface 3ba, and the inward projection 1a is substantially positioned by the reel table surface 3ba and one side 23ca of the engaging projection 23a.

As a result, even when the rotating shaft 3 vibrates in the axial direction, the inward projection 23c maintains a constant position without being affected by the vibration, that is, the position of the tape core 1 can be stabilized. Becomes

In this embodiment, the engagement protrusion 23 is formed in a substantially triangular shape because the rotary shaft 3 is attached to the tape core 1.
This is because it is easier to insert from the lower side in the axial direction, and in FIG. 8, the inward projection 1a is present at the Z position even when the rotation shaft rotates in the direction of arrow B, and the same as above. This is because the effect of is obtained.

Next, a fourth embodiment based on the present invention will be described with reference to the drawings. It should be noted that this embodiment is based on the first
Since only the shape of the engagement protrusion 3c in the embodiment of FIG.
Only the features of this shape will be mentioned here.

Referring to FIG. 9, the engaging projection 33c in this embodiment has a triangular cross section and is formed with a predetermined inclination with respect to the axial direction.

Regarding the relationship between the inward projection 1a and the engaging projection 33c, referring to FIG. 10, when the rotary shaft 3 is rotated in the direction A in the figure, the inward projection 1a includes the reel table surface 3ba and the engaging projection 33c. It is located in the space formed by one side 33ca.

At this time, a predetermined force F acts on the inward projection 1a by one side 33ca of the engaging projection 33c.

This force is applied to the inward projection 1a as shown in FIG.
Is applied to the reel table surface 3ba, so that the inward projection 1a becomes substantially the reel table surface 3ba.
And the one side 33ca of the engaging projection 33c.

As a result, even when the rotary shaft 3 vibrates in the axial direction, the inward projection 1a maintains a constant position without being affected by the vibration, that is, the position of the tape core 1 can be stabilized. It will be possible.

Next, a fifth embodiment based on the present invention will be described with reference to the drawings. It should be noted that this embodiment is based on the first
Since only the shape of the rotating shaft in the above embodiment is different, only the feature of this shape will be described here.

The structure of the rotary shaft 93 in this embodiment is as follows.
Referring to FIG. 11, it is composed of a main body shaft 3a, a reel shaft 3b, and an engagement protrusion 43c. The main body shaft 3a is fixed to a drive shaft of a drive motor (not shown), and the reel shaft 3b
Transmits the driving force to.

The engagement protrusion 43c has a predetermined uniform thickness, and its planar shape is such that it has a predetermined spread from the center portion thereof in the axially vertical direction.

Inward projection 1a and engaging projection 43 of rotating shaft 93
With respect to the relationship of c, referring to FIG. 12, when the rotary shaft 93 rotates in the direction of arrow A in the figure, the inward projection 1a becomes the engaging projection 43c.
It is located in the space formed by one side 43ca and the other side 43cb.

At this time, one side 43 of the position of the engaging protrusion 43c
A predetermined force F acts on the inward protrusion 1a by ca and the other side 43cb. This force F becomes a force F'for pressing the inward projection 1a against the recess 43e of the engaging projection 43c as shown in FIG. 11, and the inward projection 1a is substantially positioned by 43ca and 43cb.

As a result, even when the rotary shaft 3 vibrates in the axial direction, the inward projection 1a maintains a constant position without being affected by the vibration, that is, the position of the tape core 1 can be stabilized. Becomes

In this embodiment, the engaging projection 43c is formed in the shape as shown in the figure because the inward projection 1a is at the Z position even when the rotary shaft rotates in the direction of arrow B in FIG. This is because the same effect as above is obtained.

[0057]

As described above, according to the present invention,
In the tape core rotating device, by providing an engaging protrusion having an axial positioning portion that fixes the axial position of the inward protrusion by abutting the inward protrusion from above and below when viewed in the axial direction of the rotation shaft, vibration in the axial direction is reduced. Even if the table core is vibrated, the magnetic tape can travel in a predetermined manner. As a result, when the information recorded on the magnetic head is reproduced by the magnetic head, a stable reproduction output can always be obtained and high-accuracy reproduction can be performed.

[Brief description of drawings]

FIG. 1 is an overall view of a rotary shaft in a first embodiment based on the present invention.

FIG. 2 is a side view showing the relationship between the rotary shaft and the tape core in the first embodiment based on the present invention.

FIG. 3 is a top view showing the relationship between the rotary shaft and the tape core in the first embodiment based on the present invention.

FIG. 4 is a schematic diagram showing a relationship between an engaging projection and an inward projection in the first embodiment according to the present invention.

FIG. 5 is an overall view of a rotary shaft in a second embodiment based on the present invention.

FIG. 6 is a schematic diagram showing a relationship between an engagement projection and an inward projection in the second embodiment based on the present invention.

FIG. 7 is an overall view of a rotating shaft according to a third embodiment of the present invention.

FIG. 8 is a schematic diagram showing a relationship between an engagement projection and an inward projection in the third embodiment based on the present invention.

FIG. 9 is an overall view of a rotating shaft in a fourth embodiment based on the present invention.

FIG. 10 is a schematic diagram showing a relationship between an engaging projection and an inward projection according to a fourth embodiment of the present invention.

FIG. 11 is an overall view of a rotating shaft according to a fifth embodiment of the present invention.

FIG. 12 is a schematic diagram showing a relationship between an engagement projection and an inward projection in a fifth embodiment based on the present invention.

FIG. 13 is an overall perspective view of a magnetic recording / reproducing apparatus in the related art.

FIG. 14 is a diagram showing a structure of a compact cassette tape.

FIG. 15 is an overall perspective view of a rotary shaft in a conventional technique.

FIG. 16 is a diagram showing a relationship between an engagement protrusion and an inward protrusion in the related art.

[Explanation of symbols]

 1 Tape core 1a Inward projection 3,93, Rotating shafts 3c, 13c, 23c, 33c, 43, Engagement projection In addition, the same code | symbol shows the same or corresponding part in the figure.

Claims (1)

Claim: What is claimed is: 1. A rotary shaft for rotating a tape core having a central hole in which an inward projection protruding toward the center is formed, the rotating shaft being inserted into the central hole.
A tape core rotating device comprising an engaging protrusion formed on the rotating shaft to rotate the tape core together with the rotating shaft by contacting the inward protrusion, wherein the engaging protrusion is vertically movable when viewed in the axial direction of the rotating shaft. A tape core rotating device having an axial direction positioning portion for fixing the axial position of the inward projection by abutting against the inward projection.