JPS6130341B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a magnetic recording/reproducing device, and particularly aims to make an air film layer uniform on a rotating drum.

Conventionally, magnetic recording and reproducing apparatuses equipped with fully rotating drums have required some type of tape regulating means to stably run the tape on the rotating drum. As one of the configurations for this,
There is a rotating drum in which a groove is provided on the outer peripheral surface, a protrusion such as a pin is inserted into the groove, and the tape is regulated by the protrusion.

FIG. 1 shows a perspective view of a rotating drum of a magnetic recording/reproducing apparatus having such a configuration.

In the figure, reference numeral 1 denotes a rotating drum that is attached to a disk (not shown) that is integrally fixed to a main shaft (not shown) after adjusting the runout accuracy to several μm. Video heads 2 protruding by the same dimension are provided 180 degrees opposite each other. 3 is a fixed part having a bearing part. A tape regulating pin 4 is fixed to the fixing portion 3 with a screw 6, and the tip of the tape regulating pin 4 is inserted into a groove 5 provided in the rotating drum 1. Reference numeral 7 denotes a driving motor for rotating the rotary drum 1. Reference numeral 8 denotes a tape, and this tape 8 is regulated by an inlet post 9, an outlet post 10, and a tape regulating pin 4 so that it can run stably on the rotating drum 1.

FIG. 2 is a sectional view at the position of the tape regulating pin 4 shown in FIG. 1, and shows that the position of the tape is regulated by the dimension A of the tape regulating pin 4.

A drawback of the rotating drum of the magnetic recording/reproducing apparatus having the above structure is that the formation of the air film layer between the tape 8 and the circumferential surface of the rotating drum 1 is locally inhibited in the grooves 5. It has been experimentally confirmed that the smaller the depth and width of the grooves 5, the less the effect of inhibiting the formation of the air film layer, but there is a limit to how small the grooves 5 can be. , cannot be lower than a certain level.

To explain this problem in more detail, FIG. 3 is a developed view showing the positional relationship among the rotary drum 1, tape 8, and groove 5. In the vicinity of B in the figure, the air film layer is relatively thick and stable because it is close to the tape entrance side and the tape 8 is not stuck in the groove 5, but in the vicinity of C, it is far from the tape entrance side and Because the tape 8 hangs over the groove 5,
The air film layer is becoming thin and unstable.

FIG. 4 is a sectional view showing the tape floating state at position B in FIG. 3, and shows that an air film layer H is formed between the rotating drum 1 and the tape 8.

FIG. 5 is a cross-sectional view showing the tape floating state at position C in FIG. 3. FIG.

As is clear from the figure, the floating effect of the tape 8 is prevented by the grooves 5 (that is, the formation of the air film layer is inhibited), and the tape 8 comes into contact with the edges 5a and 5b of the grooves 5, damaging the tape 8. Further, local deformation of the tape 8 causes uneven head touch, making it impossible to obtain a good head output.

As explained above, in the rotating head of the conventional magnetic recording/reproducing apparatus, the formation of the air film layer is locally interrupted by the grooves, and the rotating drum and tape come into contact, which is the main cause of tape damage. Furthermore, tape deformation caused by non-uniformity in the tape flying height causes poor head touch or unstable touch, which poses a major problem in terms of life and performance.

The present invention has been made in order to eliminate the above-mentioned conventional drawbacks, and by providing a convex portion continuously along the substantially axial direction on the bottom surface of the groove of the rotary head, the air film layer can be locally localized in the vicinity of the groove. It prevents the deficiency.

DESCRIPTION OF THE PREFERRED EMBODIMENTS A magnetic recording/reproducing apparatus according to an embodiment of the present invention will be described in detail below with reference to the drawings.

FIG. 6 shows a rotating drum of a magnetic recording/reproducing apparatus according to an embodiment of the present invention, and the same parts as in the conventional example are given the same numbers.

A feature of the rotary drum is that a plurality of convex portions 9 having approximately the same height are provided on the bottom surface of the groove 5 at equal intervals. Other parts, such as the video head 2, fixing part 3, tape regulating pin 4, etc., have the same structure as the conventional example shown in FIG.

FIG. 7 shows a DD cross section of the rotating drum of FIG. 6. Now, when the rotary drum 1 rotates in the direction of the arrow E, the air near the convex portion 9 is pushed out in the direction of the arrow F, acting to levitate the tape near the groove.

FIG. 8 shows the floating state of the tape 8 at the same position as FIG. 5, which shows the conventional example. As is clear from the figure, when the rotary drum 1 rotates, air is pushed out in the direction of the arrow F by the convex portion 9, and this air flow causes the portion of the tape 8 facing the groove 5 to be locally pushed out of the rotary drum. The tape is pushed outward so that the entire tape can be floated to a substantially uniform position above the rotating drum 1. In this way, a stable head touch can be obtained in the vicinity of the groove without damaging the tape.

FIG. 9 shows another embodiment of the magnetic recording/reproducing head of the present invention, in which air supply holes 10 are provided between the convex portions 9 in FIG. 7 to make air delivery more effective. This improves the floating effect of the tape.

As explained above, the magnetic recording/reproducing device of the present invention is essential for rotating drums. This system makes effective use of the groove for inserting the tape regulating pin, and continuously provides a convex portion on the bottom of the groove. This allows for uniform formation of an air film layer for tape floating, as well as the formation of a convex portion on the bottom of the groove. It can be easily formed by knurling, etc., and has great industrial utility value.

[Brief explanation of the drawing]

Fig. 1 is a perspective view of the area around the rotating drum of a conventional recording/reproducing device, Fig. 2 is a sectional view of the position of the tape regulating pin in the same device, and Fig. 3 shows the relative positional relationship between the rotating drum, tape, and groove in the same device. A developed diagram showing,
FIG. 4 is a diagram showing the floating state of the tape near the tape input side of the same apparatus, FIG. 5 is a diagram showing the floating state of the tape near the tape exit side of the same apparatus, and FIG.
FIG. 7 is a front view of a rotating drum of a recording/reproducing device according to an embodiment of the present invention, FIG. 7 is a diagram showing the flow of air through a grooved convex portion of the rotating drum in the same device, and FIG. 8 is a diagram showing air flow in the same device. FIG. 9 is a diagram showing a floating state of the tape near the tape exit side, and is a diagram showing another embodiment of the present invention. 1...Rotating drum, 2...Video head, 3...
...Fixing part, 4...Tape regulation pin, 5...Groove, 7
...Drive motor, 9...Protrusion.

Claims (1)

[Claims] 1. A magnetic recording and reproducing device in which a protrusion is inserted into a groove provided along the outer circumferential surface of a rotating drum, and the protrusion regulates and runs the tape, in which a protrusion is continuously formed on the bottom surface of the groove. A magnetic recording/reproducing device characterized by: