JPS59154663A - Rotary head assembly - Google Patents

Abstract

(57) [Summary] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

DETAILED DESCRIPTION OF THE INVENTION Field of Industrial Application The present invention relates to a video recorder (hereinafter referred to as 'VTR').
The present invention relates to a rotary head assembly (abbreviated as "-this").

As a representative example of the conventional configuration and its problems, the VH8 type VT)t will be explained. As shown in FIG. 1, a conventional rotary head assembly includes a rotating member 2 that rotates and slides at 1800 rpm, and a non-rotating and sliding member 1 for a magnetic tape (hereinafter abbreviated as "tape") 1. A fixed cylinder 3L is provided with a lead 4 for the purpose of regulating the position of the tape 1 when ladle.The rotating member 2 is supported by a ring 3. /i7 Mounted magnetic field 5 accurately helically scans the top of Vove 1, thereby realizing reliable input and output of image enlightenment via tape 1. Since the tape 1 runs almost in contact with the fixed cylinder 3, the tape 1 receives a kinematic frictional force.Especially when VTRs are used in high humidity atmospheres or under conditions of sudden temperature changes. V soil if it is done,
Microscopic water droplets condense between the tape 1 and the fixed cylinder 3, forming a thin water film of several hours to several thousand Anges l-tr-). Due to the viscous resistance gradient of water caused by the presence of this water film, the tape 1 and the fixed cylinder 3 may completely fail to adhere, or an intermittent adhesion phenomenon may cause a type of self-excited vibration on the tape side. Often excited. In the above case, it is not possible to output accurate video and audio signals via a tape, and the performance of the VTR drops significantly or becomes completely unusable.

On the other hand, due to the necessity of developing a small and lightweight type of VTR, tapes are required to have higher magnetic recording density. In other words, the tape is made from the conventional magnetic powder of light or chlorine dioxide coated with a resin binder, and then a nickel-71-balt alloy is deposited on the resin base and coated (-/ In this case, the sliding state of the metal tag with the mating cylinder becomes metal-to-metal sliding, resulting in a relative coefficient of friction d1.
, the higher it becomes, ensuring the stability of tape running and becoming dull.

Therefore, in order to eliminate the above-mentioned drawbacks, the present inventors developed a second method.
We have already proposed a new type of rotary head assembly with the configuration shown in the figure as a representative example. In this case, the spiral group 6 provided in a specific part of the rotating member 2 or fixed cylinder 3 is activated by the rotation of the rotating member on the rotating door assembly, and generates dynamic pressure.
Rotating member 2 and fixed cylinder 3 with tape 1 or micrometer (
Approximately 5 to 1077 th) was devised so that only the magnetic head 5 comes into contact with the tape 1. This design greatly improves the tape running characteristics of the rotary throat assembly with respect to the tape. ] Stabilization, self-excitation shooting removal,
It greatly contributes to running under environmentally resistant conditions and improving signal characteristics +r1J+-, and also has the remarkable effect of suppressing wear and deterioration of both the tape and the rotary gutter assembly.

However, with the above new configuration, the rotation of the head assembly 1-
.

In order to secure the necessary dynamic pressure to tighten the
It is necessary to suppress the clearance q between the spiral group setting piece and this opposing surface to about several tens of microns. Moreover, the discharge from spiral group 6 /E (z, t:,
Since it is inversely proportional to the square of the clearance, the discharge performance efficiency is 1
It is advisable and practical to make the clearance as small as possible in order to increase the speed of the film.-20~60μ771 clear/lanos is preferable.

- side, I- side] Clearance of 4M
Machining assembly of the cylinder 3 and the support portion 8\2--Accuracy must be strictly controlled. In addition, if it occurs in the clearance part q due to falling off during processing or dust entering the air,
There is a concern that the rotating member 2 may become locked between itself and the fixed cylinder 3 and become unable to rotate, a fatal problem.

Purpose of the Invention In view of the above-mentioned drawbacks, the present invention facilitates clearance management, avoids locking accidents of the rotating member due to drop-off of particles and contamination of dust, etc., which are problems with conventional configurations, and stabilizes the tape on the rotating head assembly. It provides rotation that improves the human output characteristics of video/VI voice double signals while maintaining the robot's levitation.

Composition of the Invention (a) The invention consists of a fixed cylinder having a fixed cylindrical portion, and a magnet having approximately the same diameter as the fixed cylinder. A rotary member holding a head, and a spiral group of Bonpau 1 type is provided on either one of the opposing surfaces formed at the relative rotation part between the fixed cylinder and the rotary member, and a spiral group setting surface is provided. The opposite surface of the plate is formed by a flat plate and a supporting member that elastically supports the flat plate. Float-1-u, video
In addition to improving the input and output characteristics of audio signals, it also makes assembly easier, and has features such as eliminating accidents when the rotating part is turned on when crowded with people in Paris or in a nitrogen atmosphere. Has the effect of hitting
do.

-P Description of the Sword Example An embodiment of the present invention will now be described with reference to the drawings.
Theory 1 + vI 1, Figure 3 shows 1 according to the first embodiment of the present invention.
,・Key) Rotation-＼Indicates the soto assembly, 9!
−i is a spiral loop provided in the rotating part, It,,, h, and d does not indicate the Suhainork loop setting area;
10 is fixed / cylinder 11. -1-, 16 is a flat plate that is the opposite surface of the inner group, 12 is a support part that supports this sexually, and q is the clearance. It is. Sorry, Figure 4 is a 1F view of the I/KoZku/Ziranoshi group on the bottom of the rotating member, and 13 is the groove of the S-5'T loop.
14 is the land.

The operation of the rotary throat assembly configured as described above will be explained below. As mentioned earlier, the discharge pressure of the Bonciaud type spiral croup changes in inverse proportion to the square of the clearance q, as shown in Figure 5, and if q is zero, theoretically infinite pressure will occur. 6. Here, as shown in FIG. 6(A), an appropriate Ij pressure is applied between the snowboard iron glue 9 and the opposing surface J:=Q-f plate 10, and as a result, Set the initial value so that the clearance q is zero. The rotational speed of the co-rotating member 15 (
1 and 1, a dynamic pressure is generated 5, and this causes a clearance q between the snow tile Ay group 9 and the flat plate 10 on the opposing surface. The phenomenon at this time will be explained in more detail. As shown in Fig. 7, it is assumed that the knocking law holds true for the Y movement of the opposing surface when the elastic inertia pressure and fl are applied at the time of initial setting. Become. On the other hand, the discharge pressure (equivalent force conversion) characteristic of the spiral group white meat is represented by a solid line 2, and it becomes stable at the intersection of the two, that is, at the clearance qO' and the discharge pressure equivalent force fo. .

If the discharge sludge equivalent force I-o of 11.1 of C4 is, what is the number of curve 1?
ki wo E and ru I),'1. fo-J-□+q. E, at least the initial setting [5, A-bullet 1'1. A 1:1 force exceeding the target pressure f will be generated during rotation and throat assembly operation. −, +i, several tens of μ
? The fine clearance q of n can be elastically protected even if particles fall off during subaru/f ral group processing or dust gets mixed in in the air. Locally deforms and avoids 7 levers.

There is no danger that τIs, +:, t will be locked and unable to rotate. , Incidentally, when the rotating head assembly is at steady rotation 11IJ (for the transitional period during which it rises to the state 11, the plate and the spiral group setting part contact and slide 1'):) 1, (, -11.9
In order to reduce the wear of both the plate and the Suba Isilgrug (-J), on the surface of the opposing surface of the temporary Speyrano 1 group ( Aso ■
It is desirable to avoid processing such as 7-in addition Y, .

The elastic body that holds the F plate (: 4rl', the entire circumference of the contact area due to the action of the support part being removed)・1/l-th I; -5, and corresponding to this averaged Ij pressure, the clearance q corresponding to the temporary change J is determined.

Therefore, the clearance in the 11-wheel rotation state is averaged and a uniform discharge pressure is ensured.

As described above, in this embodiment, by forming an elastically supported flat plate on the opposing surface of the pop-out type spiral group setting part, clearance management can be particularly easily performed, and the rotating head assembly can be Tape nL
, can be achieved efficiently. It is possible to stably avoid 1D L burrs and dust contamination in the air. .

Refer to the drawings below regarding the second embodiment of the present invention (-27
1, 8th r21 is ・1<second invention
Rotation in the example of \nodoor'' is accepted, and the no if 10 and the 91 body 1 that supports it are
This embodiment differs from the first embodiment in that the cylinder 2 is embedded inside the fixed cylinder 11. ) In particular, in the embodiment of the present invention, the identification cylinder is built inside the identification cylinder in order to avoid exposing the end face of the flat plate and the support part tJ while the tape 1 is running directly. ,
The tape reaches a steady state of operation and is kept completely floating.
In contrast to the tape running during the transient period 1, it is possible to reduce the scratches, wrinkles, and local wear of the tape by 1 to 1F.

In addition, in the first and second embodiments, VH8 type VT
Rotation of the upper cylinder (equivalent to a rotating member) represented by R, rotation of the fixed type of lower cylinder - Explanation about the gutter assembly 1~, but the above content is that t t ,,,,)
Needless to say, the present invention can also be applied to a type of rotary head assembly in which a rotary member that spatially holds a magnetic head rotates, which is located in the center of two fixed cylinders with one lower cylinder identified. Furthermore, the above content holds true in all cases where a spiral group is provided in any part of the structure that produces relative velocity in the rotary head assembly L. Therefore, for example, XiZ on the rotating member side
Even if a plate and a support member are arranged and a spiral group is provided on the fixed cylinder side, the effect can be considered to be the same.

The initial clearance q is d and zero if the pressurization can be reduced, but it can also be set at a constant value with the pressurization set to zero. However, in this case, the discharge performance of the spiral group is lower than before.

Effects of the Invention As described above, the present invention provides a fixed cylinder having a fixed cylindrical portion, and a magnetic cylinder having approximately the same diameter as the fixed cylinder. A pump-out type spiral group is provided on either side of the opposing surfaces formed in the relative rotation part between the fixed cylinder and the rotating part, and a spiral group setting surface is provided. The opposing surface of the tape is formed by a flat plate and a support member that elastically supports the flat plate, allowing the tape to stably float above the rotating head assembly and improving the input/output characteristics of video and audio signals. At the same time, it is easy to assemble and eliminates the possibility of locking the rotating part due to dirt or dust in the air, which has great practical effects.

[Brief explanation of the drawing]

Figure 1 is a perspective view of a conventional rotating head assembly, and Figure 2 is a perspective view of a conventional rotating head assembly, and Figure 2 shows a spiral group provided on the surface facing water molecules.
3 is a sectional view of the rotating throat assembly in the first embodiment of the present invention, FIG. 4 is a front view of the spiral group, and FIG. 5 shows the clearance and discharge pressure of the spiral group. 6(A) and 6(B) are explanatory diagrams of the operation in the first embodiment of the present invention, and FIG. 7 is the initial dosage amount and clearance in the embodiment of the present invention. FIG. 8 is a partial sectional view of a second embodiment of the present invention. 9-... Spiral group, 10... Flat plate, 1
1--Fixed cylinder, 12--Support member, 15-
・Rotating club kidnapped. Name of representative JIJJ Patent attorney Toshio Nakao and 1 other person
Figure 1 Figure 3 Figure 4 Figure 5 Figure 6 (c) (B2

Claims (1)

[Scope of Claims] (1) A fixed cylinder having a fixed cylindrical portion, and a magnetic head having approximately the same diameter as the fixed cylinder and disposed on the same axis near the fixed cylinder. a holding and rotating member, the fixed cylinder and the +i;
i] A Bongaudo type spiral group is provided on a part or all of one of the opposing surfaces formed in the relative rotation part between the rotating member, and the opposing surface of the spiral group setting surface is connected to the flat plate and the above-mentioned A rotating head assembly formed by a support layer that elastically supports the deck. (2) The rotary head assembly according to claim 1, in which the flat plate and the supporting member are built inside the opposing surface of the spiral group setting surface (3) having approximately the same diameter. It consists of a pair of fixed cylinders arranged on the same axis with a gap between them, and a rotating member that is provided in the gap around the same axis as the fixed cylinder and that holds a magnetic head. , a pump-out type spiral group is provided on a part or all of one of the opposing surfaces formed in the relative rotation part between the fixed cylinder and the rotating member, and the opposing surface of the spiral group setting surface is provided with a pump-out type spiral group. , a bi-rotary head assembly formed by a flat plate and a support member elastically supporting the flat plate. (4) Claim 3, wherein the flat plate and the supporting member are built into the opposing surface of the spiral group setting surface.
II+1 rolling head assembly as described in Section 2.