JPS6123582B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention provides a tape lifting device for lifting a magnetic tape away from the rotating head using a fluid device when the rotating head is not performing recording/reproducing in a magnetic tape recording/reproducing device having a rotating head. It is related to.

Conventional magnetic tape recording devices using a rotating head perform recording and playback while the magnetic tape is suspended and supported by air bearings, but one of the problems with this device is that the magnetic tape, head, rotor, and air bearings are There is a wear problem with. When recording and reproducing magnetic tape, the rotor and head rotate at a high speed of 25 meters per second and come into contact with the tape, causing wear and tear on the magnetic tape and head. In addition to recording and reproducing, the air pressure for levitating the magnetic tape and the atmospheric pressure become the boundary at the entrance/exit of the head to the magnetic tape, so the amount of levitation of the magnetic tape becomes small, and the relationship between the head/rotor and the magnetic tape becomes smaller. Wear occurs. Furthermore, the amount of levitation of the magnetic tape at the entrance/exit portion of the magnetic tape on the air bearing becomes extremely small, and when the magnetic tape runs, the magnetic tape comes into contact with the surface of the air bearing, potentially damaging the recording surface. Although it is currently impossible to completely eliminate damage to the head and magnetic tape due to such wear during recording and playback, it is possible at times other than during recording and playback. It was possible to reduce wear and prolong life by separating the head from the head by a large distance, but this had the disadvantage that adding special equipment would increase costs. In recent years, there has been a method shown in FIG. 1 that reduces this wear and extends the life of the magnetic tape and head. In other words, Figure 1 is from JP-A-51-
51916 is a perspective view of the tape recording device described in US Pat. The device shown in FIG.
There is a rotor 12 that rotates between the air bearings 11 and 1. The rotor includes a magnetic head 13, and a magnetic tape 14 is helically wound around a cylindrical body made up of the air bearing 11 and the rotor 12. The magnetic head 13 maintains a certain level of levitation by the air blown out from the micro holes 10 in the rotor 12, and performs recording and reproduction by the magnetic head 13.
Air is also blown out from the gap 16 between the head 2 and the air bearing 11 to separate the magnetic tape 14 from the magnetic head 13, thereby reducing damage to the head and magnetic tape due to wear and extending the life of the magnetic tape. However, in such a tape lifting device, the width of the gap 16 is the same along the entire circumference, so even if air is blown from the gap 16, the air from the gap in the area 17 where the magnetic tape 14 is not covered is The leakage was large and tape lifting had no effect except in the vicinity of the magnetic head 13. That is, it has not been possible to increase the amount of tape floating in the conventional head inlet/outlet portion 18 and tape inlet/outlet portion 19 as shown in FIG. 2, and the problem of contact wear has not been completely solved.

The present invention eliminates the conventional drawbacks in such a tape lifting device, and instantaneously increases the amount of lift of the entire tape including the tape entrance/exit and head entrance/exit sections except during recording and playback, thereby lifting the magnetic tape, head, and rotor. It is an object of the present invention to provide a tape lifting device that minimizes wear on the tape and extends its life.

According to the present invention, the rotor is composed of a rotating rotor having a magnetic head and microholes, and an air bearing that is fixed separately on both sides of the rotor on the same axis and has a large number of microholes. When recording and reproducing a magnetic tape wound around an air bearing, the magnetic tape is suspended and supported by the air blown out from the micro-holes, and other than when recording and reproducing, the magnetic tape is suspended around the head and between the rotor and the air bearing. In a magnetic tape recording device that blows air out of a gap to levitate a magnetic tape, a tape lifting device in which the width of the gap between the rotor and the air bearing is wider in an area covered by the magnetic tape than in other areas. is obtained.

Embodiments of the present invention will be described below based on the drawings. FIG. 3 is a perspective view of an embodiment of the present invention;
FIG. 4 is a sectional view of the embodiment shown in FIG. 3. A rotor 32 is sandwiched between two air bearings 31 and rotated by a driving source (not shown). The magnetic head 13 is included in the rotor 32 and has an air bearing 31
The magnetic tape 14 is wound obliquely at an angle of 180 degrees on a cylindrical surface formed by a rotor 32 and a rotor 32 for recording and reproducing information. These two air bearings 31
A step is provided on the side surface of the air bearing 31 so that the gap 33 within the range around which the tape is wound among the gaps generated between the air bearing 32 and the rotor 32 is widened, and the other gaps 34 are narrowed. This step can be easily manufactured by machining. Air blown out from the air bearing 31 passes through a passage 35, an air chamber 36, and is blown out through a microhole 10. Further, the air blown out from the rotor 32 passes through a passage 37, a passage 38 in the rotating shaft, and an air chamber 39, and is blown out through the microholes 10. Air from the wider gap 33 is blown out through the passage 40. A tape lifting operation in this magnetic tape recording device is performed by air blown out from a wide gap 33. In other words, the gap 34 where the magnetic tape 14 is not wound and communicates with atmospheric pressure is narrower than the wide gap 33, so there is greater resistance to air flow, and the air is blown out from the wide gap 33 because it is a so-called throttle. . At this time, air bearing 31
The amount of levitation of the magnetic tape 14, which had been levitated only by the air blown out from the small holes of the rotor 32, increases over the entire area, and this happens instantaneously. This means that the air sealed in the gap 33 is the air bearing 3
1 and the tape on the rotor 32 are further lifted to escape into the atmosphere. Furthermore, even if the pressure within the gap 33 is about half the pressure of the air sent to the air bearing 31 or the rotor 32, the amount of levitation of the magnetic tape 14 will be increased by more than three times. It has an amplifying effect. This means that the same pressure source as the air blown out from the air bearing 31 and the rotor 32 can be used without using any special equipment, and the cost is low. Further, this increase in tape floating amount occurs instantaneously as air is blown out of the gap 33 as the valve is opened and closed, and has the effect of preventing time loss. This levitation amount increase ratio is determined by the ratio of the widths of the wide gap 33 and the narrow gap 34, and the desired levitation amount increase can be obtained through experiments. To give a specific example of an increase in the amount of levitation, the magnetic tape 14, which is buoyed by 50 microns when the pressure inside the air bearing 31 and rotor 32 is 500 millimeters of water column, has a gap of 3.
When an internal pressure of 200 millimeters of water was applied to 3, the amount of buoyancy increased instantaneously to 150 microns.

Another embodiment of the above embodiments of the present invention is shown in FIG. This is similar to the conventional magnetic tape recording apparatus, which records and reproduces a magnetic tape 14 which is helically wound (360 degrees) around a rotor 32 including an air bearing 31 and a head 13. In this device as well, there is a region of the gap between the rotor 32 and the air bearing 31 that is not covered by the tape, and the gap is narrowed in this region, and the magnetic tape 14 is
By widening the width of the gap in the area covered by the magnetic tape and letting air out, the amount of levitation of the entire magnetic tape 14 can be increased.

As described above, according to the present invention, in addition to recording and reproducing the magnetic tape, the levitation amount of the entire magnetic tape is instantly increased, contact wear between the magnetic tape and the head rotor and the air bearing surface is eliminated, and the head and magnetic tape are It is possible to obtain a tape lifting device that has a long life, is easy to manufacture, and is inexpensive.

[Brief explanation of the drawing]

FIG. 1 is a perspective view of a magnetic tape recording device with a conventional tape lifting device, FIG. 2 is an enlarged sectional view of the tape entrance/exit to the air bearing, and FIG. 3 is a perspective view showing an embodiment of the present invention. , Figure 4 is the third
FIG. 5 is a perspective view showing another embodiment of the present invention. In the figure, 10...microhole, 11...air bearing, 12...rotor, 13...magnetic head, 14...magnetic tape, 15...head window, 1
6... Gap, 17... Area not covered by tape,
18... Head entrance/exit section, 19... Tape entrance/exit section, 31... Air bearing of the present invention, 32...
Rotor, 33...wide gap, 34...narrow gap,
35... Air passage for air bearing, 36, 39
... Air chamber, 37, 38 ... Air passage for rotor,
40...Gap air passage.

Claims (1)

[Claims] 1 Consists of a rotating rotor having a magnetic head and micro holes, and an air bearing fixed separately on the same axis on both sides of the rotor and having a large number of micro holes, and wound around the rotor and the air bearing. When recording and reproducing a magnetic tape, the magnetic tape is suspended and supported by the air blown out from the micropores, and other than during recording and reproduction, in addition to the micropores,
In a magnetic tape recording device that suspends the magnetic tape by blowing out air around the head and from the gap between the rotor and the air bearing, the width of the gap between the rotor and the air bearing is equal to the width of the gap between the area covered by the magnetic tape and the gap in other areas. A tape lifting device characterized by being wider than the width of the tape lifting device.