JPH04222954A - Rotary head cylinder device - Google Patents

Abstract

PURPOSE:To offer a rotary head cylinder device for a video tape recorder in which a tape does not form a recessed part, because it is the cause of damaging the tape that the tape is pushed in the inner part of a head window part and forms the recessed part in the rotary head cylinder device. CONSTITUTION:A hole 38(2nd aperture part) is provided on the upper surface of an upper drum and a 1st aperture part 18 and the 2nd aperture part 38 are connected, so that air is sucked from the 2nd aperture part 38 and allowed to blow out by the 1st aperture part 18 to prevent the recessed part of the tape from being formed.

Description

[Detailed description of the invention]

0001

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a rotating head cylinder device for a magnetic recording/reproducing device.

0002

2. Description of the Related Art In recent years, magnetic recording and reproducing devices are desired to have higher performance. Particularly, since the rotating head cylinder device directly contacts the magnetic tape, it is a part that affects the stable running of the magnetic tape.

An example of the above-mentioned conventional rotary head cylinder device will be described below with reference to the drawings.

FIG. 6 is a front view of a conventional rotary head cylinder device, and FIG. 7 is a partial sectional view taken along arrow line B-B in FIG.
8 is a partial plan view taken along arrow line CC in FIG. 7. FIG.

Next, the structure and operation will be explained. First, there is a rotary head cylinder consisting of a lower drum 12 that helically wraps and guides the magnetic tape 10, and an upper drum 16 that is rotationally driven in the direction of arrow A by a motor 14. The device is fixed to the upper drum 16 and the head window 1
A magnetic head 20 protruding from the magnetic head 8 records and reproduces signals on the magnetic tape.

[0006]

However, in the above configuration, the opening area suddenly increases at the head window 18, as shown in FIGS. 7 and 8. The magnetic tape 10 is pressed against the drum surface by tape tension, but since there is nothing to support the pressing force at the position of the head window 18, the magnetic tape 10 deforms into the shapes shown at 22a, 22b, 22c, and 22d. . As a result, tape damage occurs due to the edges 24a, 24c, and 24d of the head window 18. In particular, the rear edge 24 of the upper drum 16 in the rotational direction
d and the edges 24a parallel to the rotational direction are likely to cause damage to the tape, and the magnetic tape 10 also becomes longer and thinner, becoming less rigid and becoming increasingly deformed 22.
There was a problem in that the lengths a to 22d were large and the tape was easily damaged.

SUMMARY OF THE INVENTION In view of the above problems, the present invention provides a rotary head cylinder device that provides stable tape running performance.

[0008]

[Means for Solving the Problems] In order to achieve the above object, the present invention provides a fixed cylindrical lower drum, a rotating upper drum having a magnetic head on its outer periphery, the lower drum and the upper drum. A rotary head cylinder device for recording and reproducing signals by scanning a magnetic tape wound around the outer periphery of the upper drum with the magnetic head, wherein a first opening from which the tip of the magnetic head protrudes is provided on the outer periphery of the upper drum; A second opening connected to the first opening is provided on the upper surface of the upper drum, and the second opening is positioned inside the first opening on the radius of the upper drum. Air is sucked in through the second opening and blown out through the first opening.

[0009]

According to the present invention, with the above-described structure, stable tape running can be obtained without damaging the magnetic tape at the head window portion.

0010

DESCRIPTION OF THE PREFERRED EMBODIMENTS A rotary head cylinder device according to an embodiment of the present invention will be described below with reference to the drawings.

FIG. 1 is a perspective view of the head window of the upper drum of a rotary head cylinder device according to an embodiment of the present invention, FIG. 2 is a partial sectional view showing the structure of the same part, and FIG. FIG. 2 is a plan view taken along arrow line D-D of No. 2;

Note that the configuration and operation are exactly the same as those described in the conventional example shown in FIG. 6, and will therefore be omitted. In addition, parts with the same function are given the same number.

Here, the points different from the conventional example will be explained using FIGS. 1 to 3. A head base 30 to which the magnetic head 20 is fixed is fixed to the upper drum 16 with screws 32.

A groove 34 is provided in the head base 30 mounting portion of the upper drum 16. Width B of this groove 34
is narrower than the width C of the head base 30, and the magnetic head 20
It is set wider than the width D of. The depth E of the groove 34 is set so that it does not extend beyond the rear end F of the head base 30.

Therefore, when the head base 30 is fixed with the screws 32, the groove 34 is covered by the head base 30, and only the head window 18 (first opening) is open.

The upper drum 16 is provided with an air hole 38 penetrating from the upper end surface 36 into the groove 34, and furthermore, the upper end surface 36 of the upper drum 16 is provided with an opening of the air hole 38 (a second The opening) is covered with an umbrella-shaped cover 40 with a hole 42 at the center of rotation.

In the rotary head cylinder device constructed as described above, the head window 18 is opened from the hole 42 provided at the center of the cover 40 through the air hole 38 and the groove 34.
The area up to becomes a tunnel-like air flow path.

As shown in FIG. 6, the upper drum 16 is driven to rotate at high speed in the direction of arrow A by the motor 14, and the magnetic head 20 records and reproduces signals on the magnetic tape 10. At this time, the centrifugal force generated by the rotation Air is drawn in through the holes 42 through the air flow path described above and blown out through the head window 18.

Originally, the opening area suddenly widened at the head window 18, and the magnetic tape 10 was pushed into the head window 18, but this was canceled by the above-mentioned air blowout, and the opening of the magnetic tape 10 became extremely large. This prevents deformation of the part from occurring.

As a result, the edges 24a of the head window 18,
The contact between 24c and 24d becomes weaker, and the occurrence of tape damage is drastically reduced.

In particular, even if a long-duration tape with low rigidity is used, the amount of suction at the head window 18 is small, and the edges 24a, 2
Tape damage caused by 4c and 24d is less likely to occur.

Next, another embodiment of the present invention will be explained using FIGS. 4 and 5. The structure and operation are the same as those described in FIGS. 1-3, but the difference is in the diagonal hole 50. The diagonal hole 50 has a lower end 52 provided within the groove 34 and an upper end 54 provided on the inner circumferential side of the lower end 52.

Due to this difference in radius, air is sucked in from the upper end 54 of the diagonal hole 50 by the centrifugal force generated by the rotation of the upper drum 16, blows out from the head window 18 through the lower end 52, and prevents the magnetic tape 10 from being sucked in. I will do it.

[0024]

As is clear from the above description of the embodiments, the present invention utilizes centrifugal force generated by rotation to blow air out of the head window and prevent the magnetic tape from falling into the head window. Excellent effects such as preventing tape damage can be obtained.

Furthermore, since energy is not wasted in deforming the tape due to falling into the head window, the load on the motor and load fluctuations are reduced, contributing to a reduction in jitter.

[Brief explanation of the drawing]

FIG. 1 is a perspective view of a head window of an upper drum of a rotating head cylinder device according to an embodiment of the present invention.

[Figure 2] Partial sectional view showing the configuration of the same location as Figure 1

[Figure 3
] Plan view taken along arrow line D-D in FIG.

FIG. 4 is a partial sectional view of the head window of the upper drum of a rotating head cylinder device according to another embodiment of the present invention.

[Fig. 5] Plan view along arrow line E-E in Fig. 4

[Fig. 6] Front view showing the operation of a conventional rotating head cylinder device.

[Fig. 7] Partial cross-sectional view taken along arrow line B-B in Fig. 6.

[Figure 8]
Plan view taken along arrow line C-C in FIG.

[Explanation of symbols]

10 Magnetic tape 12 Lower drum 16 Upper drum 18 Head window (first opening) 20 Magnetic head 30 Head base 34 Groove 38 Air hole (second opening) 40 Cover 50 Diagonal hole

Claims (5)

[Claims] 1. A drum that is rotatably driven and equipped with a magnetic head on its outer periphery for recording and reproducing signals on a magnetic tape, the drum having a continuous space for air flow, and having a continuous space for air flow; An opening is provided on the head window side of the drum, a second opening is provided on the inner peripheral side of the head window, and the air sucked through the second opening is blown out to the first opening. Rotating head cylinder device. 2. A fixed cylindrical lower drum, a rotating upper drum equipped with a magnetic head on the outer periphery, and a magnetic tape wound around the outer periphery of the lower drum and the upper drum, which is scanned by the magnetic head. In a rotary head cylinder device for recording and reproducing signals by recording and reproducing signals, a first opening from which the tip of the magnetic head protrudes is provided on the outer periphery of the upper drum, and a second opening connected to the first opening is provided on the outer periphery of the upper drum. provided on the upper surface of the drum, with the second opening located inside the radial position of the first opening on the radius of the upper drum;
A rotary head cylinder device configured to suck air through an opening and blow it out through the first opening. 3. The first opening is formed by covering a groove provided on the radius of the lower surface of the upper drum and extending from the middle of the radius of the upper drum toward the outer periphery with a head base to which a magnetic head is adhered. The rotary head cylinder device according to claim 2. 4. Covering the second opening provided on the upper surface of the upper drum with a cover at a distance from the upper surface of the upper drum,
4. The rotary head cylinder device according to claim 3, further comprising an air inflow hole provided in the center. 5. Claim 2, wherein the hole connecting the first opening and the second opening is provided at an angle with respect to the rotation axis of the upper drum.
The rotating head cylinder device described.