JPH04301257A - Rotary magnetic head device - Google Patents

Abstract

PURPOSE:To provide a rotary magnetic head device in which a favorable contact state can always be obtained between a tape and a gap part at a head chip tip part without being influenced by the variation of the tension of the wound tape. CONSTITUTION:A smooth projecting part 11 whose height is almost equal to the projecting amount of the tip part is provided at the upper part position of a hollow space part 6 from which the tip part of the head chip 4 of a rotary drum 1 is protruded.

Description

[Detailed description of the invention]

0001

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a rotating magnetic head device, and more specifically, in a rotating head type DAT or VTR, recording/reproduction on a tape is performed by a magnetic head disposed around the periphery of a rotating upper drum. The present invention relates to a rotating magnetic head device.

0002

2. Description of the Related Art FIG. 3 shows the state of a conventional rotary magnetic head device during recording/reproducing operations. Here, 1 is a rotating upper drum (hereinafter referred to as a rotating drum), and 2 is a fixed lower drum (hereinafter referred to as a rotating drum).
(hereinafter referred to as a fixed drum), 3 is a head chip mount attached to the rotating drum 1, 4 is a head chip mount 3
The head chip 5 attached thereto is an adjustment screw for adjusting the vertical position (hereinafter referred to as height) of the head chip 4 in the recessed space 6 into which the magnetic head is mounted. Note that the tip of the head chip 4 is attached so as to slightly protrude from the circumferential surface of the drums 1 and 2.
The upper and lower portions of the gap portion 4A formed at the tip are protected by a filler material 4B of non-magnetic material such as glass or ceramic. 4C is a coil for the head, 4D is a window for attaching the coil 4C to the head chip 4, and 7 is a tape as a recording medium that is held wound around the circumferential surfaces of the drums 1 and 2.

In the rotating magnetic head device constructed in this manner, the tape 7 is wound obliquely around the circumferential surfaces of the rotating drum 1 and the stationary drum 2, and the rotating drum 1 rotates together with a rotating shaft (not shown). Then, the tape 7 further runs. At this time, by keeping the tip end of the chip 4 in contact with the tape 7, recording or reproduction is performed according to a track corresponding to the vertical width of the gap portion 4A.

0004

However, in such a conventional rotary magnetic head device, the tension of the tape changes depending on the winding position on the drum, and when the tension is small, the tension as shown in FIG. In this way, the tape 7 is held with a relatively large radius of curvature near the tip of the head chip 4. In such a case, the tape 7 will come into contact with the drum in a somewhat unstable state, but there will still be a gap between the tape 7 and the tape 7 near the gap portion 4A of the head chip 4. There is no need to worry about spacing loss. However, as shown in FIG. 4(b), when the tension of the tape 7 is large, the head chip 4
The bending of the tape 7 near the tip of the tape 7 has a small radius of curvature, resulting in a gap between the gap portion 4A and the tape 7, resulting in a spacing loss due to poor contact.

[0005] Also, the height of the gap portion 4A in the recessed space 6 varies widely due to manufacturing reasons.
However, if the tip of the head chip 4 is tilted too much by such adjustment, the tape 7
Since there is a risk of spacing loss due to poor contact between the gap portion 4A and the gap portion 4A, the height adjustment amount is severely restricted.

Furthermore, the gap portion 4 at the tip
For example, a plurality of heads may be combined so that the heights of A are approximately the same, or a shim for adjustment may be sandwiched between the head chip mount 3 and the rotating drum 1 in advance. There were coordination problems.

An object of the present invention is to solve the above-mentioned conventional problems by ensuring good contact with the tape at the head gap at all times without being affected by changes in tape tension. Another object of the present invention is to provide a rotating magnetic head device that is easy to adjust.

[0008]

[Means for Solving the Problems] In order to achieve the above object, the present invention provides a state in which the tip of a head chip is projected from the peripheral edge of a rotating upper drum into a recessed space formed along the peripheral edge of the rotating upper drum. In a rotating magnetic head device, the rotating magnetic head is held at
A smooth convex portion having a protrusion height that is approximately the same as the amount of protrusion of the tip portion is provided at an upper position of the rotating upper drum from which the tip portion of the head chip protrudes, and the convex portion and the tip portion of the head chip are connected to each other. It is characterized in that the tape is brought into contact with.

[0009]

[Function] According to the present invention, a smooth convex portion having a protrusion amount approximately equal to the protrusion amount of the head chip tip portion is provided above the recessed space from which the head tip tip portion of the rotating upper drum protrudes. When the tape is wound and comes into contact with the tip of the head chip, the radial force due to the tension of the tape is shared between the tip of the head chip and the convex part, and the area near the tip of the head chip By keeping the radius of curvature of the bend caused by the tension of the tape large, a good contact state can be maintained between the tape and the gap.

0010

DESCRIPTION OF THE PREFERRED EMBODIMENTS Examples of the present invention will be described in detail and specifically below with reference to the drawings.

FIGS. 1 and 2 show an embodiment of the present invention. In these figures, reference numeral 11 indicates the distance between the drum 1 and the upper part of the recessed space 6 from which the head chip 4 of the rotating drum 1 is projected.
The protrusion height of the protrusion 11 is set to be approximately the same as the protrusion amount of the head chip 4, as shown in FIG. As shown in FIG. 1, the overall shape of the convex portion 11 is such that the above-mentioned maximum protrusion height is maintained at the center of the circumferential width of the head chip 4, and its both sides and upper surface are not angular. It is preferable to have a rounded shape and gradually lower the height. In addition, in FIG. 2, D
represents the thickness at the tip of the head chip 4, B represents the width of the gap portion 4A, and the vertical width B of this gap portion 4A corresponds to the width of the track on the tape 7. Further, a dashed line indicates a displacement position when the position of the head gap 4A is adjusted by pushing down the head chip 4 via the mounting base 3 with the adjustment screw 5.

According to the rotating magnetic head device constructed in this manner, the tension in the width direction of the tape 7 is carried by both the convex portion 11 and the tip of the head chip 4.
Even when the tension is large, the tape 7 is not deformed into a curve with a small radius of curvature at the tip of the head chip, and therefore there is no gap between the tape 7 and the gap portion 4A as shown in FIG. 4(b). never occurs. Furthermore, even if the height of the gap portion is adjusted by the displacement of the head chip 4 as shown by the dashed line, it is possible to maintain good contact between the tape 7 and the gap portion 4A. .

In the embodiments described above, the convex portion 11 is molded integrally with the rotating drum 1, but instead of this, a member having a similar convex portion may be formed separately from the rotary head 1. However, it goes without saying that it may be fixed along the lower edge of the circumferential surface of the rotating drum in the form shown in FIG. Further, the above embodiment is an example of application to a drum in which the fixed drum 2 has a diagonal lead 8 and the tape is wound diagonally around the drum circumferential surface, as shown in FIG. However, the application of the present invention is not limited to this system, but can also be widely applied to other types of rotating magnetic head devices in which a rotating drum is provided with a magnetic head and recording/reproduction is performed by contacting with a tape.

[0014]

As described above, according to the present invention, the top position of the rotating upper drum from which the head chip tip is protruded has a protrusion height that is approximately the same as the amount of protrusion of the tip. Since a smooth convex portion is provided and the tape is brought into contact with the convex portion and the tip of the head chip, the following effects can be obtained.

(1) The tension generated on the tape changes between the tape winding start position and the position where the tape leaves the drum due to the relationship such as friction between the tape and the drum. The tape can be kept in stable contact with the gap portion of the head chip, and spacing loss can be prevented.

(2) By widening the height adjustment range of the head gap, there is no need for an optical combination work process for height adjustment between multiple heads, and the above-mentioned height adjustment There is no need to use shims for adjustment.

(3) When the tape is under high tension, the tape is prevented from being damaged by the corner of the tip of the head chip, and the tip is prevented from being worn to one side.

(4) Since a good contact condition at the gap part is now guaranteed, it is possible to increase the thickness of the head chip itself, and the contact area with the tape at the tip of the head chip can be increased. Therefore, the life of the head can be extended against wear.

[Brief explanation of drawings]

FIG. 1 is a perspective view showing one embodiment of the present invention.

FIG. 2 is a sectional view of the head chip attaching portion according to the present invention in the direction of the drum axis.

FIG. 3 is a cross-sectional view of a conventional head chip mounting portion in the drum axis direction.

FIG. 4 is an explanatory diagram showing, in cross section, the state of contact with the tip of the head chip when the tape tension changes according to a conventional example.

[Explanation of symbols]

1 Rotating drum 2 Fixed drum 4 Head chip 4A Gap part 5 Adjustment screw 6 Recessed space 7 Tape 11 Convex part

Claims (1)

[Claims] 1. The tip of the head chip is held in a concave space formed along the periphery of the rotating upper drum in a state where it projects from the periphery, and the tip is brought into contact with the running tape. In a rotating magnetic head device,
A smooth convex portion having a protrusion height that is approximately the same as the amount of protrusion of the tip portion is provided at an upper position of the rotating upper drum from which the tip portion of the head chip protrudes, and the convex portion and the tip portion of the head chip are connected to each other. A rotating magnetic head device characterized in that the tape is brought into contact with the tape.