JPS60177413A - Multi-channel magnetic head - Google Patents

Abstract

PURPOSE:To prevent the mixture of dust, etc. on a tape rubbing surface of a magnetic head into a head gap by providing plural grooves on said tape rubbing surface which are parallel to each other and oblique to the tape driving direction. CONSTITUTION:Plural grooves which are parallel to each other with a prescribed sloping angle theta to the tape driving direction are formed to a display device 7 of a reproduction head 2. The angle theta is set at 1-30 deg.. While the pitch of the groove 9 is set approximately equal to a track pitch together with 0.1-20mum depth. Thus the dust, etc. attached onto the tape rubbing surface of a magnetic head are drifted toward an end direction of the tape owing to the grooves 9. As a result, the mixture of such dust, etc. can be avoided into a head gap part 8.

Description

DETAILED DESCRIPTION OF THE INVENTION Field of the Invention The present invention relates to a magnetic head, and more particularly to a structure of a magnetic head that has multiple channels and has good contact with a magnetic chip.

Conventional technology Conventionally, magnetic heads that perform recording and reproduction on magnetic tape perform their functions by constantly contacting the running magnetic tape, so in order to maintain good contact, the magnetic head is made to have a smooth, mirror-like surface. It is provided.

However, a multi-channel magnetic spatula P is commercially available which can simultaneously record and reproduce a large number of channels on a magnetic tape using this magnetic head. This multi-channel magnetic head records and reproduces multiple channels on a magnetic tape of the same width, so although the areal recording density and transmission rate are improved, it is likely to cause the following mechanical disadvantages.

With the improvement in areal recording density, the recording track width per channel has become extremely narrow. Our track width is 2
The diameter was about 0.00 μm, and a small amount of dust adhering to the head surface also affected the recording and reproducing output, causing a decrease in the recording and reproducing output.

In addition, as the recording track width becomes narrower, even slight waving (positional fluctuation in the tape width direction) that occurs during running of the case makes it difficult for the magnetic head to trace the track well, resulting in a reduction in playback output. It's easy and powerful. In particular, as linear recording density increases and magnetic recording tapes become thinner, the aforementioned output reduction and waving become more likely to occur.

OBJECTS OF THE INVENTION An object of the present invention is to eliminate the drawbacks of the multi-channel magnetic spatula described above, and to provide a multi-channel magnetic spatula P that has good contact properties with magnetic tape and is less affected by dust and the like. .

Structure of the Invention The above object of the present invention is to provide a multi-channel magnetic head for simultaneously recording and/or reproducing a large number of tracks on a magnetic tape, in which a case contact surface on at least the case incident side of the magnetic head is inclined with respect to the tape running direction. This is achieved by a multi-channel magnetic head characterized by having a plurality of mutually parallel grooves.

(Example) Hereinafter, one embodiment of the present invention will be described based on the drawings.

FIG. 1 is a schematic diagram of a connection type multi-channel magnetic head having the same structure as the conventional one. In this combination type magnetic head 1, a reproducing head 2 and a recording head 3 are connected to a seal P plate 4. It is housed integrally in case 5 via.

The surfaces of each of the spatulas P2 and 3 that come into contact with the magnetic surface of the tape T are provided in a generally arcuate shape that protrudes along the tape running direction so as to improve the sliding properties of the tape T. Further, a regulating plate 6 is provided on the side surface of the case 5 to hold the tape T in a predetermined position and regulate waving.

FIG. 2 shows, for example, a reproduction spatula P2 of the magnetic spatula)'1, FIG. 2a is a plan view, FIG. 2b is a side view, and FIG. 2c is Ir' of FIG. FIG.

The reproducing head 2 has a surface 7 that makes surface contact with the tape magnetic surface.
At approximately the top of the head gap 8i!, perpendicular to the tape running direction (arrow direction in the figure). It is formed. A plurality of spacing gaps 8 are arranged at predetermined intervals depending on the number of reproduction tracks, and form individual reproduction heads in a multi-track.

Further, the reproducing head 2 is provided with a plurality of mutually parallel grooves 9 extending over the entire area of the surface 7. The groove 9 has a predetermined inclination angle θ with respect to the tape running direction, and is formed between the adjacent heps P gaps 8. Still, the pitch of the grooves 9 is provided so as to substantially match the track pitch in which the channels are formed.

The head gap 8 portion is made of a high magnetic permeability soft magnetic material or a magnetoresistive element (MR), for example, hermalloy, ferrite, sendust, amorphous, or the like.

In addition to the high magnetic permeability soft magnetic material, the surface 7 that contacts at least the magnetic surface of the magnetic tape T, excluding the hep P gap 8, is made of a ceramic material with good free machinability (for example,
Product name Makor) Or4fC Den Kanshin.

A magnetic case T is run on the reproducing head 2 provided in this way, and the inclination angle θ is set from 00 to 60° (0° is the groove 9
This shows the case where no is formed. ), we measured the waving of the magnetic tee 7″T, and obtained the results shown in Figure 3. (The tape used was metal powder coated, tape width 3.8 mm, and coercive force. 14
00 He, tape speed 47.6 mrty': w
It is. ) It is clear from Fig. 3 that the inclination angle θ is 1.
In the range of 30° to 30°, the waving is 5μ
It was within the range of m (Peak to Peak). This value is such that a sufficient regulating effect by the regulating plate 6 can be obtained. Also, according to the measurement results, when the groove 9 is provided within the range of the inclination angle θ, and when the groove 9 is not provided (
The waving was reduced compared to the above-mentioned inclination angle θ-〇°).

Next, when the inclination angle θ was set to 8° and the cross-sectional shape of the groove 9 was selected as shown in FIG. 4, the recording wavelength λ was set to 0.8°.
The results of each error rate in μm are shown in FIG. In other words, as is clear from FIG. 5, when the cross-sectional shape of the groove 9 is substantially U-shaped, the error rate increases when the depth of the groove 9 reaches 1.5 μm (in the case of symbol (b) in the figure). It was a trend. Therefore, the depth of the groove (measured result) is 0.17
! It has been found that Zm to 20 μm is clever. Also,
When the depth of the groove 9 is kept the same and only the shape is changed, the cross-sectional shape is approximately U-shaped, and the numbers (d) and (e) in FIG.
When formed as shown in K, the error rate was reduced and favorable results were obtained. However, when forming the groove 9, a substantially U-shape is formed.

6 and 7 are modified examples of the ladder of this embodiment. 6th
The figure shows a groove 10 having an inclination angle θ similar to the embodiment shown in FIG. 30°). The head gap 2'11 is formed perpendicularly to the groove 10 and is inclined at a constant angle α with respect to the tape running direction. By forming the head gap 7'll in this way, the gap length can be shortened and the number of channels can be increased. However, when the head gap 11 is formed as in this modified example, the reproducing head 20 of FIG. 21 are arranged in a direction perpendicular to the tape running direction, and a vertical groove 22 extending along the spacing gap 21 is provided on the surface of the tape incident side with the spacing gap 21 as a boundary. There is. Furthermore, a groove 23 having an inclination angle θ similar to that shown in FIG. 2 is provided in communication with the vertical groove 22. The angle of inclination θ is within the preferred range (1° to 3o0) obtained in FIG.

Even when the present invention was configured as the modified example shown in FIGS. 6 and 7, the same effect was obtained.

Effects of the Invention As described above, the present invention forms an inclined groove on the tape sliding surface of a multi-channel magnetic head, so that dust etc. adhering to the sliding surface is swept toward one end of the tape, and the head gear is Entry into the lug section can be prevented.

Further, since the dust and the like are easily carried by the grooves, good contact between the magnetic head and the tape can be maintained. Furthermore, the slope of the groove reduces the force that would bias the tape in one direction, thereby suppressing the occurrence of waving. These results show significant improvements in tape waving and output error rates.

[Brief explanation of the drawing]

FIG. 1 is a schematic configuration diagram of a multi-channel magnetic head for explaining the present invention, FIG. 2 is a diagram for explaining a reproducing head according to an embodiment of the present invention, and FIG. 3 is a waving diagram of a magnetic tape according to the present invention. Measurement results: FIG. 4 is a diagram showing the cross-sectional shape of the groove according to the present invention, FIG. 5 is a measurement result of the error rate based on FIG. 4, and FIG. 6 is a plan view of the magnetic spatula P according to a modification of the present invention. , FIG. 7 is a partial perspective view of a magnetic head according to another modification of the present invention. Reference numeral 1 in the figure: Combination type magnetic head, 2.20.
...Reproducing head, 3... Recording head, 4... Shield plate, 5... Case, 6... Regulating plate, 7... Surface, 8, 11° 21... Head gap, 9 ,10.2
3...Groove, 22...Vertical groove. Representative Patent Attorney (8107) Kiyotaka Sasaki (and 3 others) Figure 1 Figure 4t! 1 No. 3 Figure 4 #1. C θ (°) Figure 6 , Figure ■ Procedural Amendment 1981 Month Yu? Dear Commissioner of the Japan Patent Office (Dear Patent Office Examiner) 1. Indication of the case Patent Application No. 32688 of 1982 2. Name of the invention Multi-channel sulfur head 3. Relationship with the person making the amendments (11 cases), Patent applicant Name (520) Fuji Photo Film Co., Ltd. Kasumigaseki Building Post Office Post Office Box No. 49 Eikou Patent Office Telephone (581)-9601 (Representative) Showa (Month, Day, Showa) 6. Inventions increased by amendment 0 7 Subject of amendment ``Detailed description of the invention'' Column 8, Contents of amendment)'' Procedural amendment May 1, 1981, Case indication 1982 Special Patent Application No. 32688+32, Name of invention Multi-channel magnetic head 3, Person making the amendment Relationship to the case Patent applicant name (520) Fuji Photo Film Co., Ltd. Kasumigaseki Building Post Office PO Box No. 49 Eiko Patent Office Telephone (581)-96Q 1 (Representative) Name Patent Attorney (8107) Kiyotaka Sasaki (3 people) 78
Column 8 of the subject of amendment "Detailed Description of the Invention" and column 8 of the content of the amendment "Detailed Description of the Invention" are amended as follows. 1) Statement 8r! In the 13th line of the 2nd sentence, insert the tape recorder J using 1 before "is commercially available." 2) On the first line from the bottom of the second page, after “the tape”, “
Insert "half the width of". 6) On page 6, line 2, "width" is corrected to "pitch." 4) On page 6, line 5, "width" is corrected to "pitch." 5) Page 4, lines 8-9, “Combi Engagement”
"Combination" is corrected. 6) On page 4, line 10, "combination" is corrected to "combination." 7) In the 10th line of the 6th line of the same text, after “coating”, “
Insert "is of type". 8) On page 9, lines 8-9, amend "from the result" to "from the cause."that's all

Claims (1)

[Scope of Claims] 1) In a multi-channel magnetic head for simultaneously recording and/or reproducing multiple tracks on a magnetic tape, on at least the tape contacting surface on the tape incidence side of the magnetic head,
A multi-channel magnetic head characterized by having a plurality of mutually parallel grooves inclined with respect to nine tape running directions. 2) The inclination angle of the groove is 1° to 3° with respect to the tape running direction.
Claim No. 1 (1) characterized in that the range is 0°.
Multi-channel magnetic spatula P03) The multi-channel magnetic spatula P0 according to Claim 1, wherein the depth of the groove is in the range of 0.1 μm to 20 μm.4) The groove The pitch of the multi-channel magnetic tool according to claim 11 is characterized in that the pitch of the track is exactly the same as the track pitch on which the channels are formed.