JPH04134613A - Magnetic head and magnetic recording and reproducing device - Google Patents

Abstract

PURPOSE:To prevent the brake of the envelope of a reproduction output by changing the core width of the sliding surface of each magnetic head chip. CONSTITUTION:Respective magnetic head chips 1-3 are constituted by holding the both sides of a cobalt base amolphous alloy magnetic material 5 with a thickness of 20mum forming a magnetic path by non-magnetic substrates. The leading magnetic head chip 1 is a laminated structure with a core width Cw11 of 180mum holding the alloy magnetic material 5 by non-magnetic substrate 6 with the thickness of 80mum respectively consisting of a nickel-titanium- magnesium base ceramic material, the magnetic head chip 2 in the center is the laminated structure with the core width CW12 of 140mum holding the alloy magnetic material 5 by non-magnetic substrate 7 with the thickness of 60mum respectively consisting of the nickel-titanium-magnesium base ceramic material, and the rearmost magnetic head chip 3 is the laminated structure with the core width CW13 of 100mum holding by non-magnetic substrate 8 with the thickness of 40mum respectively consisting of the nickel-titanium-magnesium base ceramic material.

Description

DETAILED DESCRIPTION OF THE INVENTION Field of Industrial Application The present invention relates to a magnetic head used in audio equipment, video equipment, computers, etc. In particular, it is used for high signal rate recording and reproduction to improve the contact state of magnetic tape. The present invention relates to a magnetic head and a magnetic recording/reproducing device having a structure suitable for maintaining the temperature.

BACKGROUND OF THE INVENTION In recent years, in magnetic recording and reproducing apparatuses that perform helical scanning using a rotating blade, systems for handling wideband signals such as high-quality VTRs and digital VTRs have been actively developed. In order to record and reproduce broadband signals, multi-track magnetic heads are being researched (for example, Yoda et al.; 13th Japanese Society of Applied Magnetics Academic Lecture 22pA-1
(see 5).

In order to perform multi-track recording and playback, it is better to attach multiple magnetic head chips to one window of the rotating cylinder, and in order to maintain uniform contact with the tape, the protruding shape of the magnetic head chip and the track Efforts have been made to optimize the curved surface in the width direction.

The magnetic helad chips mounted on these magnetic heads include bulk type magnetic head chips made of ferrite, or laminated type magnetic head chips in which both sides of a magnetic material forming a magnetic path are sandwiched between non-magnetic substrates. is mainly used.

In recent years, the magnetic tapes used in these magnetic recording and reproducing devices have been made thinner, increasing the length of the magnetic tape that can be stored in a unit volume, in order to meet the demand for longer-duration, larger-capacity recording. This is being actively considered. However, when the magnetic tape is made thinner, the stiffness of the magnetic tape decreases in inverse proportion to the cube of the thickness.

Problems to be Solved by the Invention When a multi-trunk magnetic head such as the one described above is used to perform recording and reproduction on a thick magnetic tape for short-time recording, the front shape of the magnetic head chip adapts to the thick magnetic tape, and the width of the magnetic hent tip changes. The radius of curvature in the direction increases. in general,
Due to the deformation of the tape due to the airflow generated by the rotation of the cylinder and the relative movement between the tape and the magnetic head, the pressure on the entrance side of the magnetic head is greater than the pressure on the exit side. especially,
In a multi-track magnetic head composed of magnetic head chips with the same core width, the wear amount of the leading magnetic head chip is greater than the wear amount of the rearmost magnetic head chip in the direction of rotation of the cylinder. The radius of curvature of the magnetic head chip in the width direction is larger than the radius of curvature of the rearmost magnetic head chip in the width direction. After this, when recording and reproducing are performed on a thin magnetic tape for long-term recording, the thin magnetic tape has a small stiffness, so the deformation of the magnetic tape in the width direction becomes large, making it difficult to contact the leading magnetic held tip. It will be enough. As a result, spacing loss increases, and the reproduction output of the first magnetic head chip becomes lower than the reproduction output of the succeeding magnetic head chips.

This is observed as a deterioration of the envelope of the output waveform.

In conventional magnetic heads, an attempt was made to improve this phenomenon by initially reducing the radius of curvature in the width direction of the magnetic hent tip, but the shape of this radius of curvature changes significantly due to wear of the magnetic hent tip, and further wear occurs. Since the radius of curvature increases with the progress of the process, no substantial improvement could be obtained.

The present invention solves the above-mentioned conventional problems, and an object of the present invention is to provide a magnetic head and a magnetic recording/reproducing device in which the reproduction output of the preceding magnetic helad chip does not decrease when performing helical scanning using a multi-track magnetic head. It is said that

In order to achieve the above object, the present invention provides a multi-trunk magnetic head having three or more magnetic head chips adjacent to each other in one mounting window of a cylinder, each magnetic head having three or more adjacent magnetic head chips. The core width of the sliding surface of the Herad tip is changed so that the amount of wear is approximately the same from the leading magnetic Herad tip to the rearmost magnetic head chip in the rotational direction of the cylinder.

Generally, when a magnetic tape and a magnetic head tip slide, the amount of wear on the magnetic head tip increases as the contact pressure increases. When the tape is slid, the pressure on the magnetic Rad tip decreases sequentially from the leading magnetic Rad tip to the last magnetic Rad tip. Therefore, the amount of wear on the leading magnetic head chip increases, and the radius of curvature in the width direction also increases.

When performing helical scanning with the multi-track magnetic head of the present invention, since the core width of the sliding surface is gradually thinned from the first magnetic head chip to the last magnetic head chip, the head protrudes due to wear of each magnetic head chip. Changes in amount can be made almost the same for all magnetic head chips. Therefore, the radius of curvature in the width direction of each magnetic head chip can be made approximately the same, and the contact with each magnetic head chip can be made approximately the same. Furthermore, even as wear progresses, each magnetic held tip maintains the same good hend contact. This effect makes it possible to substantially improve the reduction in the reproduction output of the leading magnetic herad chip.

Example Below, a magnetic head in an example of the present invention will be described.
This will be explained with reference to the drawings.

FIG. 1 is a perspective view of a magnetic head according to an embodiment of the present invention, FIG. 2(a) is a perspective view of the magnetic hesodotinop, and FIG. 2(b) is a view from the direction of the sliding surface of the magnetic head chip. It is a front view.

As shown in Fig. 1, the magnetic head is constructed by mounting on a head base 4 a leading magnetic head chip 1, an intermediate magnetic head chip 2, and a last magnetic head chip 3, which first come into contact with the magnetic tape when the flip rotates. configured.

As shown in FIGS. 2(a) and 2(b), each of the magnetic henotactics 1 to 3 is constructed by sandwiching a 20 μm thick cobalt-based amorphous alloy magnetic material 5 between non-magnetic substrates on both sides to form a magnetic path. Ru. The leading magnetic helad tip 1 has a laminated structure with a core width Cwll-180 μm in which an alloy magnetic material 5 is sandwiched between non-magnetic substrates 6 each made of a nickel-titanium-magnesium ceramic material and each 80 μm thick. is a core width Cw1 in which an alloy magnetic material 5 is sandwiched between non-magnetic substrates 7 each made of a nickel-titanium-magnesium ceramic material and each having a thickness of 60 μm.
The last magnetic head chip 3 has a core width Cw1 sandwiched between nickel-titanium-Mag7 ceramic substrates 8 each having a thickness of 40 pm.
3=100 μm laminated structure.

Next, a description will be given of a magnetic head used in a magnetic head according to a 20th embodiment of the present invention. FIG. 3(a) is a perspective view of the same magnetic Radiation chip, and FIG. 3(b) is a front view of the same Magnetic Radiation chip as seen from the sliding surface direction. Figure 3 (
As shown in a) and (b), the core width Cw2 is almost the same.
After attaching the leading magnetic head chip 21 having a magnetic head chip 21, the middle magnetic head chip 22, and the last magnetic head chip 23 to one helad base, attach the core of the tape sliding surface on the entry side of the leading magnetic head chip 21 to the leading magnetic head chip 21. By polishing the side surface of the magnetic head chip with an inclined surface 24 such that the relationship between the width Cw21 and the core width Cw22 of the tape sliding surface on the exit side of the last magnetic head chip 23 is Cw21>Cw22. , a magnetic head according to a second embodiment of the present invention is formed. According to this configuration, since the core widths of the magnetic head chips 21 to 23 are almost the same, the magnetic head chips can be manufactured under the same manufacturing conditions, and the trunk height can be easily adjusted, resulting in excellent mass productivity. . Although FIG. 3 shows an example in which both sides of the magnetic head chip are polished, a similar effect can be obtained by polishing only one side and narrowing the core width of the last head chip.

Next, a description will be given of a magnetic head used in a magnetic head according to a third embodiment of the present invention. FIG. 4(a) is a perspective view of the magnetic held tip, and FIG. 4 (2) is a front view of the magnetic held tip viewed from the sliding surface direction. Figure 4 (a
), (b), a leading magnetic hend chip 31, an intermediate magnetic helad chip 32, and a last magnetic hent chip 33 having the same core width Cw31 are manufactured. The intermediate magnetic held tip 32 and the last magnetic held tip 33 have a core width of Cw32. Cw33 (Cw33<Cw32<C
W31), and the part to be bonded to the helad base remains Cw31, using a dicing saw, a precision slicer, a laser processing machine, an electrical discharge machine, etc., to process the parts in steps almost parallel to the running direction of the head. This constitutes a stepped portion 34. According to this configuration, since the core widths of the head chips in the portions to be bonded to the henode heses are approximately the same, it is easy to adjust the track heights and is excellent in mass production. Although FIG. 4 shows an example in which both sides of the magnetic head chip are stepped, a structure in which only one side is stepped and the core width is narrowed has the same effect.

The embodiment described above is based on the case where there are three magnetic head chips, but the magnetic head of this configuration has the same effect even when four or more magnetic head chips are installed in one head mounting window of the cylinder. Needless to say, it shows.

In addition, the magnetic head of this structure can also be used in a method other than the above, in which each magnetic head chip sequentially moves from the core width of the gap portion of the first magnetic head to the core width of the gap portion of the last magnetic head in the rotational direction of the cylinder. The effect of the present invention can be obtained by configuring the core width of the gap portion of the structure to be narrower, and the magnetic node of the present structure can be applied not only to the magnetism of the laminated structure but also to the bulk type ferrite m gas. It goes without saying that the same effect can be obtained by using a metal-in-gap structure magnetic tip. In addition, the magnetic head of this structure is applicable not only to a magnetic recording/reproducing device using a rotating/ring, but also to a structure in which a rotating head rotates between two fixed cylinders, or a structure in which a magnetic head is fixed and a magnetic medium slides at high speed. It goes without saying that the same effect can be obtained as a multi-track magnetic head used in the configuration.

Next, a magnetic recording/reproducing apparatus according to an embodiment of the present invention will be described with reference to the drawings.

FIG. 5 is a block diagram of a magnetic recording/reproducing apparatus according to an embodiment of the present invention. Magnetic tape 41 has inclined posts 42, 43
The rotating cylinder 44. It is wound around a fixed cylinder 45. With respect to the rotational direction of the rotary cylinder 44 that performs helical scanning, the leading magnetic head chip 46 has a core width of 180 μm, and the middle magnetic head chip 47 has a core width of 1 μm.
40 μm, the last magnetic head chip 4B has a core width of 10
For example, the magnetic head chip 1 shown in FIG.
This corresponds to 3.

On the other hand, in a conventional magnetic recording/reproducing device using a multi-track magnetic head configured with the same core width, the leading magnetic head receives stronger contact pressure than the succeeding magnetic heads.
As wear progresses, the radius of curvature in the width direction increases. For this reason, when a thin magnetic tape is recorded and reproduced after running on a thick magnetic tape, the contact condition of the leading magnetic head deteriorates, and the reproduction output decreases.

Envelope waveform diagrams of reproduction output in a conventional magnetic recording and reproduction apparatus are shown in FIGS. 7(a) to 7(C) for comparison. Note that (a) shows the first magnetic head chip, (bl shows the middle one, and (C) shows the last one.In this way, with respect to the running direction, the envelope of the leading magnetic throat chip is severely collapsed. In contrast, in the magnetic field of the present invention, since the core width becomes thinner from the first magnetic head chip to the last magnetic head chip, the change in the protrusion amount due to wear is almost equal, and the The radii of curvature of the curvatures of the magnetic recording and reproducing apparatus according to the present invention are approximately the same. Therefore, good output characteristics can be obtained even when recording and reproducing thin magnetic tapes. Figures (a) to (C) show the reproduction output characteristics of the magnetic head chip (al indicates the head chip, (b) the middle part, and (C) the last part). Furthermore, a magnetic recording/reproducing apparatus using the magnetic head of the present invention can obtain a uniform envelope output.

Furthermore, since the change in the amount of head protrusion due to wear of each magnetic head chip is approximately equal, the running time until the gear and the depth open are approximately equal, and the life of each magnetic head chip is uniform.

Effects of the Invention As described above, the magnetic head of the present invention is a multi-track magnetic head in which the leading magnetic head chip has a thicker head core width than the trailing magnetic head chip, and the contact state between the magnetic head and the magnetic tape is maintained at all times. The structure maintains a good level of playback output and prevents a decrease in playback output due to spacing loss, that is, a collapse of the enheropsis of playback output. In addition, even if the magnetic head chip wears out, a good front surface shape is maintained, so it has extremely high industrial value.

[Brief explanation of the drawing]

Fig. 1 is a perspective view of a magnetic head according to an embodiment of the present invention, Fig. 2U(a) is a perspective view of a magnetic head chip used in the magnetic head, and Fig. 21m(b) is a perspective view of the magnetic head chip used in the same magnetic head as viewed from the sliding direction. 3(a) is a perspective view of a magnetic head chip used in a magnetic head according to a second embodiment of the present invention, and FIG. FIG. 4(a) is a perspective view of a magnetic head chip used in a magnetic head according to a third embodiment of the present invention, and FIG. 41F(b) is a front view of the same magnetic head chip as seen from the sliding direction. , FIG. 5 is a configuration diagram of main parts of a magnetic recording/reproducing apparatus according to an embodiment of the present invention, FIGS. 6(a) to (C) are envelope waveform diagrams of reproduction output of the magnetic recording/reproducing apparatus according to the present invention, and FIG. Figures (a) to (C) show the reproduction ratio of the conventional magnetic recording and reproducing device C to 3. Vomit H pull R Ku shout m-! Ap

Claims (7)

[Claims] (1) A multi-track magnetic head having three or more magnetic head chips adjacent to each other in one mounting window of a cylinder, characterized in that the core width of the sliding surface of each magnetic head chip is changed. magnetic head. (2) The magnetic head according to claim 1, wherein the core width of the sliding surface gradually becomes narrower from the first magnetic head chip to the last magnetic head chip. (3) The magnetic head according to claim 1, wherein the core width of the gap portion gradually becomes narrower from the first magnetic head chip to the last magnetic head chip. (4) Claim 1 using a magnetic head chip having a configuration in which both sides of a magnetic body forming a magnetic path are sandwiched between non-magnetic substrates.
The magnetic head described. (5) The magnetic head chip is characterized by having an inclined surface on the side surface of the head chip so that the core width of the sliding surface of the first magnetic head chip is thicker than the core width of the sliding surface of the last magnetic head chip. A magnetic head according to claim 1. (6) It has a configuration with a stepped portion approximately parallel to the running direction of the head so that the core width of the sliding surface of the leading magnetic head chip is thicker than the core width of the sliding surface of the trailing magnetic head chip. The magnetic head according to claim 1, characterized in that: (7) A magnetic recording and reproducing device using a multi-track magnetic head having three or more magnetic heads in one window of a rotating cylinder, characterized in that the magnetic head according to claim 1 is used. Device.