JPS62245560A - Head projection adjusting mechanism - Google Patents

Abstract

PURPOSE:To obtain a stable head touch over the entire recording and reproducing area by increasing gradually the projection of a magnetic head to a magnetic sheet toward the outer circumference of the magnetic sheet from the inner circumference and increasing the projection abruptly at the outer circumference. CONSTITUTION:If a tracking command is given, a motor 11 is driven and a head carriage 14 is moved by the turning of a screw shaft 13, a head projection adjusting mechanism 10 uses an elastic member 17 to move a magnetic head 18 supported by the head carriage 14 in the direction Y. Then a bottom face 20c of a holder 20 of the magnetic head 18 is pressed onto a guide regulation face 19a of a lower guide member 19 by the elastic force of the elastic member 17, and the sliding face of a head chip 22 of the magnetic head 18 to the magnetic sheet 2 is moved in the direction of Y while being regulated at a height according to the shape of the guide regulating face 19a. Thus, the height of the head chip 22 rises slightly and then abruptly toward the outer circumference of the magnetic sheet 2 from the inner circumference. Thus, excellent head touch is obtained even near the outermost circumference.

Description

[Detailed Description of the Invention] "Industrial Application Field" This invention provides a head protrusion adjustment mechanism, more specifically,
The present invention relates to a head protrusion amount adjustment mechanism that allows a magnetic head to stably touch the recording medium in a magnetic recording and reproducing apparatus that performs magnetic recording and reproduction on a sheet-like rotating magnetic recording medium.

[Prior Art] In order to perform recording and reproduction using a sheet-like rotating magnetic recording medium (hereinafter abbreviated as "magnetic sheet"), it is necessary to stably slide a magnetic head for recording and reproduction on the rotating magnetic sheet. It is necessary not only to ensure that the recorded/reproduced information does not have any noise or dropouts, but also to avoid output fluctuations.

Due to its rigidity and the centrifugal force acting on each part, the magnetic sheet rotates while being stretched in a substantially horizontal direction while forming air layers on both sides. However, if you simply press the magnetic head against the magnetic sheet I, this magnetic sheet will -
1- Since it bends downward, the tip part of the magnetic head cannot be brought into stable sliding contact with the magnetic sheet. Therefore, in general, Figures 5 and 6 (A), (B
), the magnetic head 3 is received by two parallel pads 4 and 5 with a magnetic sheath 1-2 rotating in the X direction around the support 1 in between. The magnetic head 3 is attached to the magnetic sheet 2 in its radial direction (Y) for tracking.
J.

The two pads 4.5 are moved intermittently by a head feeding device (i), and the two pads 4.5 are moved intermittently by a head feeding device (i) on both sides of the magnetic head 3. Along the length <1; Therefore, in a magnetic recording/reproducing device using such parallel J(11 pads 4 and 5), the magnetic sheet 2 is moved to the magnetic head by the butt 4.5, as shown in FIG. 6(A), (+3). By being pushed toward the magnetic head 3, the portion facing the magnetic head 3 is bent, and the magnetic head 3 is tightly pressed against the magnetic head 3.

[Problem to be solved by the invention] By the way, the patent application 1986=518 proposed earlier by the present applicant
As mentioned in the specification of No. 22, the spatula touch of the magnetic head 3 with respect to the magnetic sheet 2 is different depending on whether the magnetic spatula l' 3 is located close to the center of the magnetic sheet 2 or far from the center. different. In other words, when the parallel pad 4°5 as described above is used, the short deflection of the magnetic sheet when the magnetic head 3 is located near the center of the magnetic sheet I. Since the force and the bending force of the long distance 1JIE of the magnetic sheet when the magnetic head is located near the outer periphery of the magnetic sheet are naturally different, the pressing force of the magnetic sheet against the magnetic head 3 is also different in each case. The head touch of the magnetic head on the magnetic sheet changes depending on the position of the magnetic head in the Y direction.

Therefore, as the magnetic head moves from the inner circumferential side to the outer circumferential side of the magnetic sheet in Japanese Patent Application No. 1980-51822, the present applicant changed the amount of protrusion of the magnetic head relative to the magnetic sheet over the entire range of movement in the Y direction. Although attempts were made to gradually increase the amount linearly or stepwise, good head touch could still not be obtained in the outer circumferential portion of the magnetic sheet 2.

This means that when the magnetic head 3 reaches the tracking position on the outer periphery of the magnetic sheet 2, as shown in FIGS. This is because it will be in a completely lifted state without being bent toward the head side.

This invention was made in response to the above-mentioned problems, and it is possible to improve recording + recording on the magnetic sheet, including the outer periphery of the magnetic sheet where particularly good head touch could not be obtained.
It is an object of the present invention to provide a head protrusion pattern adjustment mechanism that allows a stable head touch of 1-(1'-) over the entire area of the +j raw area.

[Means and operations for solving the problem] The head protrusion amount adjustment frame structure of the present invention moves the magnetic head for tracking along the radial direction of the magnetic sheet with respect to the magnetic sheet that is the recording medium. The magnetic head has a head guide means for regulating the protrusion 1 of the contact surface of the magnetic head with respect to the magnetic sheet, and as the magnetic head moves from the inner circumferential side to the outer circumferential side of the magnetic sheet as it is regulated by the head guide means. The amount of protrusion of the magnetic head relative to the magnetic sheet gradually increases, and increases even more sharply near the first round of the magnetic head, and the magnetic head extends over the entire recording and reproducing area relative to the magnetic sheet 1. Sliding contact occurs with almost equal contact pressure.

[Example] Hereinafter, the present invention will be explained based on illustrated embodiments.

1 and 2 are an enlarged plan view and sectional view of a head protrusion gauge and a reduction mechanism showing an embodiment of the present invention. In Figure 1.2, this head protrusion m adjustment mechanism 1
a head feeding motor 11; a screw shaft 13 connected to the output shaft of the motor 11 by a coupling 12;
A head carriage 14 is attached to this screw shaft 13 by screwing, a round bar-shaped support part 15, 16 that movably supports this head carriage 14, and one end is attached to the lower end of the head carriage 14. A fixedly supported thin plate-shaped elastic part +A'17, a magnetic head 18 attached to the other end of this elastic part 17, and this magnetic head 18 are placed on the magnetic sheet 2 which is a recording medium. On the other hand, the magnetic head 18 mainly includes a head guiding portion 19 which controls the protruding acid of the magnetic head 18.

The screw shaft 13 is arranged so that the extension line of its central axis coincides with the radial direction of the magnetic sheet 2 so that it intersects the center line of the shaft 1 of the magnetic sheet 2, and is parallel to the screw shaft 13. 1- Since the supporting portions 15 and 16 are provided, when the motor 11 rotates, the head carriage 14 is moved in the radial direction of the magnetic sheet 2 by the screw feeding caused by the rotation of the screw shaft 13.

The lower end of the head carriage 14 has reached a position lower than the height of the magnetic sheet 2, so that the elastic part 17, whose one end is fixed to the head carriage 14, is arranged horizontally.
The other end is located below the magnetic sheet 2. The elastic portion 17 is normally used as a spring plate, and is made of non-magnetic materials such as beryllium, phosphorus, and copper. A magnetic head 1 is attached to the other end of the elastic portion 17.
8 comes into contact with the magnetic sheet 2 whose two sides are regulated by the pads 4 and 5 at an intermediate position between the pads 4 and 5.

The magnetic head 18 is mounted at the other end of the thin plate-shaped elastic part 17, for example, with a configuration as shown in an enlarged view in FIG.
I'm being kicked. That is, a notch 17a is formed at the center of the other end of the elastic portion 17 to receive the holder 20 of the magnetic head 18. Parts of both left and right sides of this notch 17a are bent downward at right angles, and a screw 21 is inserted into a hole formed in the bent side, and the screw 21 is placed in the notch 17a to form a holder 20. The holder 20 is held by being screwed into a screw hole on the side surface of the holder.

The holder 20 forms a magnetic head 18 by fitting and fixing a head chip 22 into four chip mounting portions 20a formed on the top surface.

1. In the elastic part housing 1-7 having the magnetic head 18, the part holding the magnetic head 18 is always urged downward due to its elastic behavior, and the lower end of the bottom surface 20b of the holder 20 is connected to the head guide member 19. The height position of the magnetic head 18 is regulated by coming into contact with the head guide regulating surface 19a on the upper surface.

The head guide member 19 is a stationary part at the bottom of the magnetic recording/reproducing apparatus within a range that can support the magnetic head 18 when the magnetic head 18 moves in the radial direction (Y direction) of the magnetic sheet 2 for tracking. It is permanently installed in the building. The head guide regulating surface 19a on the upper surface of the head guide member 19 extends from one end of the inner peripheral side of the magnetic sheet 2 near the axis 1 to the magnetic sheet 1.
A region 19 at the other end that rises at a gentle inclination angle toward the vicinity of the other end on the outer periphery of the magnetic seam 1-2 and faces the outer periphery of the magnetic seam 1-2.
In ao, the magnetic sheet 2 stands at an angle that approaches the magnetic sheet 2 relatively steeply. Regarding the protrusion size of the other end of the magnetic sheet 2 with respect to one end of the head guide regulating surface 19a as a reference, for example, a 3.5-inch magnetic sheet (innermost track diameter 49.4φ, outermost track Diameter 79φ
) is used as a tower, it is desirable that h=about 100 μm.

A straight groove 19b that coincides with the radial direction of the magnetic sheet 2 is perpendicularly formed in the head guide regulating surface 19a of the head guide member 19 from one end to the other end. This straight groove 19b is for preventing horizontal vibration of the magnetic head 18-9, and the straight groove 19b includes a protruding piece 20b vertically provided at the center of the bottom of the holder 20 of the magnetic head 18. Sliding automatic / [Incorporated into. The depth dimension of the linear groove 19b is set such that when the protruding piece 20b is fitted into the linear groove 19b, the lower end of the bottom surface 20C on both sides of the protruding piece 20b of the holder 20 comes into reliable contact with the head guide regulation surface 19a. Bottom surface 20 of the protruding piece 20b
The protrusion from the lower end of c is sufficiently larger than the J method (see Figure 2).

In one head protrusion adjustment mechanism configured as described above, when a tracking command is given and the motor 11 rotates and the head carriage 14 moves due to the rotation of the screw shaft 13, the elastic part 17 moves the head carriage. The magnetic head 18 held by the magnetic head 14 moves in the Y direction.

At this time, since the protruding piece 20b is fitted into the -1-2 straight groove 19b, the magnetic head 18 moves only in the Y direction along the straight groove 19b without tilting or wobbling laterally. The bottom surface 2 of the holder 20 of the magnetic head 18
Since the resiliency of the Occurrence Lit member 17 presses against the head guide regulating surface 19a of the head guide member 19, the surface of the magnetic head 18 that slides against the magnetic sheet 2 of the head tip 22 also contacts the guide regulating surface 19a. It moves in the Y direction while being restricted to a height position according to the shape. Therefore, when the magnetic head 18 moves from the inner circumferential side to the outer circumferential side of the magnetic seam 1-2, the height of the RAD tip 22 rises slightly toward the outer circumferential side, and further near the outermost circumferential portion. When the holder 20 is in the facing position,
1. Since the contact surface of the head chip 22 with respect to the magnetic sheet 2 reaches the region 19ao of the guide regulation surface 19a, the contact surface of the head chip 22 also rises with a steep slope. Therefore, the contact pressure of the bed chip 22 with respect to the magnetic sheet 2 becomes uniform, and good head touch can be obtained, especially near the outermost periphery, where good head touch has been achieved up to now. The magnetic head 18 can perform recording and reproduction in a stable head touch state from the inner circumferential side to the outermost circumferential side.

In addition, in the embodiment mentioned above, the holder 20 of the magnetic head 18
The structure is such that the protruding piece 20b formed in the above shape is fitted into the straight groove 19b of the head guide member 19 to prevent the horizontal vibration of the magnetic head 18. However, as the elastic member 17, it has elasticity only in the vertical direction, and has elasticity in the horizontal direction. If one that does not displace is used, the structure for preventing lateral vibration of the magnetic head 18 in the above embodiment can be omitted.

Further, as an example of a pot-shaped structure in which the magnetic head 18 is attached to the elastic member 17, for example, as shown in FIG. There is a notch 17A in the center of the end of A for picking up the magnetic head.
b, and part of the left and right sides 17Ao at the opening end of the notch 17Ab is filled with water l'J' on the left and right sides of the holder 2OA.
It can also be a simple structure in which it is fitted and fixed to r20d.

Furthermore, in the above embodiment, the head carriage 14 is moved by a screw feeding mechanism by rotation of the screw shaft 13, but the structure is not limited to this, and for example, the output shaft of the motor and the helad carriage are moved. They may be connected by a leaf spring having a so-called α-wound structure.

[Effects of the Invention] As described above, according to the present invention, the amount of protrusion of the magnetic head relative to the magnetic sheet gradually increases from the inner circumferential side to the outer circumferential side of the magnetic sheet. Since it is made to increase steeply at the outer periphery where the magnetic sheet was not affected, stable head touch can be achieved over the entire small recording area of the magnetic sheet, and the head touch is particularly good at the outer periphery of the magnetic sheet. As a result, it is possible to perform excellent recording and +Ij raw with a good IIf raw envelope and no noise or dropout.

[Brief explanation of drawings]

FIG. 1 is a lateral enlarged plan view of a head projection amount adjusting device showing an embodiment of the present invention, FIG. 2 is a longitudinal sectional side view of the head projection amount adjusting mechanism shown in FIG. 1, and FIG. "-2 An assembled perspective view showing an enlarged main part of the mechanism shown in Figs. 1 and 2. Fig. 4 is an assembled perspective view showing an example of the shape of the connection structure between the magnetic head holder and the elastic member. , a schematic 1ε-diagram showing the relationship between the magnetic head and pads of a conventional magnetic recording/reproducing device, and FIGS. 6(A) and (
13) are cross-sectional views taken along lines A-A and B-B in FIG. 5 above, respectively, and FIGS. These are cross-sectional views taken along line A-A and line B-B in FIG. Magnetic sheet (
Sheet-shaped rotating magnetic recording medium) 3.18...Magnetic head 4.5...
......1 pair of pads 10...
...Head protrusion adjustment mechanism 19...
...Head guide member (head guide means)

Claims (1)

[Scope of Claims] A magnetic head is moved in the radial direction of the recording medium to switch the tracks of the recording medium on a surface of the sheet-like rotating magnetic recording medium opposite to the side where the magnetic head is arranged. In a magnetic recording/reproducing device in which the recording medium is regulated by a pair of pads arranged parallel to the locus of movement, the magnetic head moves along the radial direction of the recording medium. The head guide is configured such that the amount of protrusion of the contact surface of the magnetic head relative to the recording medium is gradually increased from the inner circumferential side to the outer circumferential side of the recording medium, and increases sharply near the outer circumferential portion. A head protrusion amount adjustment mechanism characterized by comprising means.