JPH02306409A - Magnetic tape recording/reproducing device - Google Patents

Abstract

PURPOSE:To secure a stable head touch by forming two grooves centering on a magnetic head on the tape running surface of a head block so as to generate the negative voltage between the magnetic head and the magnetic tape by the running of the magnetic tape. CONSTITUTION:Two grooves 7 are formed centering on a magnetic head 1 on the running surface 6 for a magnetic tape 2 of a head block 5 buried into the head 1. The head 1 contains a pair of cores 8 buried into the center part of the block 5 and a gap 9 formed between both cores 8. The surface 6 serves as the upper surfaces of both head 1 and the block 5 where the tape 2 has the reciprocating motions in the direction orthogonal to the gap 9. In such a constitution, the flow of air generated by the running of the tape 2 flows along the grooves 7. As a result, the fluid film pressure is reduced on the upper surface of a core gap part and the spacing value is reduced.

Description

[Detailed Description of the Invention] <Industrial Application Field> The present invention relates to a data magnetic tape recording/reproducing device, which suppresses the gap that occurs between a magnetic head and a magnetic tape during recording/reproducing, and achieves high density It is used for recording and reproducing.

<Prior art> Magnetic tape storage devices (called data streamers) used for data exchange and data storage, especially as a backup device for fixed magnetic disk devices, have recently become larger in capacity and faster due to the increase in disk capacity. has become an important issue. Specifically, this increase in capacity is a shift from megabytes to gigabytes.

As a data streamer, it is first necessary to increase the recording density in order to meet such an increase in capacity. To achieve this, several measures are required, including minimizing the minute gap (spacing gap) that occurs between the magnetic head and the magnetic tape during recording and reproduction to improve the efficiency of recording and reproduction output. It is very important to reduce spacing loss.

The following factors may cause this spacing gap to occur.

1) Caused by surface roughness of the magnetic head and magnetic tape 2) Tape contact pressure on the magnetic head and head touch structure 3) Fluid film (air film) from the magnetic tape inlet side to the magnetic head due to high-speed tape running What can be done Regarding the spacing gap caused by this fluid, the following equation is well known.

Spacing amount (μM) ho=k −R, (, 6μv/T) 2/3 ・
(,4) Here, R: Head radius μ: Raw fluid viscosity coefficient V: Tape speed T: Tape tension: As a result of analyzing the current spacing amount according to the above factors, contact pressure, head touch, air film It was found that the influence of

Therefore, when considering each parameter for reducing the spacing amount from the above spacing amount equation (1), it is better to first make the head radius smaller, but this response is local to the tape. This is not a good idea as the tape will be subject to pressure and deformation, and the tape will be damaged.

Next, it is better to increase the tape tension, but this approach also poses a problem in the longevity of the tape due to an increase in the load torque of the tape drive motor and the tape being tightly wound around the tape guide.

Next, regarding the tape speed, if you slow down the tape speed,
Although the amount of spacing will be reduced, this will go against the goal of achieving higher speeds.

In view of the above, what needs to be solved is to eliminate the fluid pressure near the surface of the magnetic head so that the state of contact (head touch) of the bracket to the surface of the magnetic head with the magnetic tape is reliable and stable.

Therefore, Fig. 4 shows a conventionally known method in which the magnetic tape 2 is pressed against the magnetic head 1 from the back with a pad such as felt to ensure head contact. However, the output fluctuation was extremely large and unstable, making it unusable for high-speed tape running devices.

<Problems to be Solved by the Invention> With a structure in which magnetic tapes are simply brought into contact and run as in the prior art described above, the amount of spacing is large and expensive for devices such as data streamers that run tapes at high speeds. It's a matter of dense recording and playback.

Therefore, we experimented and investigated the method shown in FIG.

This is done by forming a groove 4 with a maximum depth of several 100 μm in a part other than the core gear part on the contact surface of the magnetic head 1 with the magnetic tape 2, and directing the air flow caused by the running of the tape into the groove 4.
The purpose is to reduce the spacing amount by lowering the fluid film pressure on the upper surface of the core gap portion.

The result is that the tape speed is 2.5% compared to the case without grooves.
Although the spacing amount was reduced by about 12% under the condition of ~3.0 m/s, and the effect of the grooves was confirmed, this level was still insufficient.

In view of the above, it is an object of the present invention to provide a magnetic tape recording and reproducing apparatus that can suppress the gap between a magnetic tape running at high speed and a magnetic head, and can obtain stable head touch.

<Means for Solving the Problems> As shown in FIGS. 1 and 2, the means for solving the problems according to the present invention is as shown in FIGS.
The magnetic head 1 is placed on the running surface 6 by the running of the magnetic tape 2.
A groove 7 for generating negative pressure between the magnetic head 1 and the magnetic tape 2 is formed to sandwich the magnetic head 1.

<Operation> In the above problem solving means, when the magnetic tape 2 runs at high speed on the surface of the magnetic head 1, the magnetic tape 2 entrains the surrounding air. However, since this air flow flows out along the groove 7, the inside of the groove 7 becomes a negative pressure, and the magnetic tape 2 is attracted by the negative pressure and runs inside the groove 7.

Then, the magnetic tape 2 runs while being pressed against the magnetic head 1, the spacing gap decreases, and the magnetic tape 2 is brought into stronger contact with the magnetic head 1.

Therefore, by providing the negative pressure generating groove 7 on the running surface 6 of the magnetic tape 2 of the head block 5, it is possible to suppress the spacing gap and obtain a stable head touch.

<Example> Hereinafter, an example of the present invention will be described based on the drawings. 1st
2 is a plan view of a head block showing an embodiment of the present invention, FIG. 2 is a sectional view taken along line A--A in FIG. 1, and FIG. 3 is a plan view of a head block showing another embodiment.

As shown in the figure, the magnetic tape recording and reproducing apparatus of the present invention has a magnetic head 1 and a magnetic tape 2 opened by running the magnetic tape 2 on the running surface 6 of the magnetic tape 2 of the head block 5 in which the magnetic head '1 is embedded. A groove 7 for generating negative pressure is formed between the magnetic head 1 and the groove 7 .

The magnetic head 1 includes a pair of cores 8 fitted into the center of a head block 5, and a gap 9 formed between the cores 8.

The running surface 6 of the magnetic tape 2 is connected to the magnetic head 1.
and the upper surface of the head block 5, on which the magnetic tape 2 is moved back and forth while sliding in a direction perpendicular to the gap 9.

The grooves 7 are formed on both sides of the upper surface of the head block 5, sandwiching the magnetic head 1 therebetween, and have a depth of about 10 μm. A triangular running surface 6 is formed parallel to the running direction of the magnetic tape 2 toward the magnetic head 1.
The surface area of the groove 7 increases as it approaches .

In the above configuration, when the magnetic tape 2 runs at high speed on the surface of the magnetic head 1, the magnetic tape 2 draws in the surrounding air, and air flows between the magnetic tape 2 and the magnetic head 1, creating a spacing gap. do.

However, since this air flow flows out along the groove 7, the inside of the groove 7 becomes negative pressure. Since the shape of the groove 7 is such that the surface area becomes larger in the vicinity of the magnetic head 1, the magnetic head 1 is attracted by the negative pressure there and travels inside the groove 7.

Then, the magnetic tape 2 runs while being pressed against the magnetic head 1, the spacing gap decreases, and the magnetic tape 2 is brought into strong contact with the magnetic head 1.

Therefore, by making the running surface 6 of the magnetic tape 2 of the head block 5 negative pressure and providing a groove for generating negative pressure so as to spread the negative pressure distribution near the magnetic head 1, the spacing gap can be suppressed. 7= Moreover, it ends with obtaining a stable head touch.

Further, FIG. 3 shows the shape of the groove 7 when the present invention is used when two magnetic heads 1 are arranged in parallel.

In this case, the outer grooves 7a of the magnetic heads 1a, 1b
The shape of the magnetic head 1 is the same as that of the above embodiment, but the magnetic head 1
The shape of the groove 7b sandwiched between at 1 b is constricted at the center so that the area of the groove becomes larger in the vicinity of the magnetic head. In this case as well, the same effects as in the above embodiment can be obtained.

It should be noted that the present invention is not limited to the above embodiments, and it goes without saying that many modifications and changes can be made to the above embodiments within the scope of the present invention.

For example, the shape of the groove 7 is not limited to that of this embodiment.
It may be formed so that the depth thereof gradually becomes deeper as it approaches the magnetic head.

<Effects of the Invention> As is clear from the above description, according to the present invention, a magnetic tape is formed on the running surface of the magnetic tape of the head block in which the magnetic head is embedded, due to the running of the magnetic tape = 8 - between the rad and the magnetic tape. Since the grooves that generate negative pressure are formed between the magnetic heads, negative pressure is generated near the magnetic heads, which suppresses the spacing gap and has the excellent effect of achieving stable head touch. be.

[Brief explanation of the drawing]

FIG. 1 is a plan view of a head block showing an embodiment of the present invention, FIG. 2 is a sectional view taken along line A-A in FIG. 1, FIG. 3 is a plan view of a head block showing another embodiment, and FIG. This figure shows the relationship between a conventional magnetic head and a magnetic tape, and FIG. 5 shows the relationship between an improved prototype magnetic head and magnetic tape. 1: Magnetic head, 2: Magnetic tape, 5: Head block, 6: Running surface, 7: Groove.

Claims (1)

[Claims] A magnetic device characterized in that a groove is formed on the running surface of the magnetic tape of a head block in which the magnetic head is embedded, sandwiching the magnetic head, so that a negative pressure is generated between the magnetic head and the magnetic tape as the magnetic tape runs. Tape recording and playback device.