JPH0341338Y2 - - Google Patents

Description

[Detailed Description of the Invention] [Industrial Application Field] This invention relates to a magnetic head assembly used in a drive device for a disk-shaped magnetic recording medium.

[Conventional technology]

A magnetic head assembly used for recording and reproducing a disk-shaped magnetic recording medium (hereinafter referred to as a disk) usually has a side that can be opened via a hinge on the side where the disk is inserted, and when the disk is inserted, The arm closes to allow recording and playback. When the arm is closed, the magnetic head and disk are brought into sliding contact with each other by a predetermined sliding force to perform recording and reproduction.
In both single-sided and double-sided recording, the sliding contact force is adjusted by the pressing force (load pressure) of the arm toward the carriage.

Examples of such magnetic head assemblies include those shown in FIGS. 4 and 5.

FIG. 4 and its partial sectional view, FIG. 5, show a conventional example of this type of magnetic head assembly, which is proposed in U.S. Pat. No. 4,323,938.

In FIGS. 4 and 5, 51 is a carriage with a lower magnetic head 52 attached to its tip, and 53 is an arm with an upper magnetic head 54 attached to its tip, and both magnetic heads 52 and 54 are substantially opposed to each other. It is arranged like this. 55 is a leaf hinge spring, one end of which is fixed to the carriage 51 by a screw 56, and the other end is fixed to the arm 53 by a screw 57, so that the arm 53 can be rotated by the carriage 51. is connected to. Reference numeral 58 denotes a lifting protrusion provided on one side of the distal end of the arm 53. By lifting this protrusion 58 by a lifting mechanism (not shown), the arm 53 is lifted.
moves upward with the base end on the side of the leaf hinge spring 55 as the center of rotation. 59 is a curved surface formed at the base end of the arm 53, and this curved surface 59 smoothly contacts the upper surface of the leaf hinge spring 55 as the arm 53 rotates. 60 is a tension spring, one end of which is connected to the carriage 5 through a stopper 61.
1, the other end is attached to the arm 53 via an adjustment screw 62, and the arm 53 is constantly pressed toward the carriage 51 by the tension spring 60. A stopper 63 is provided on the carriage 51, and controls the rotation angle of the arm 53 to prevent excessive upward movement.

When the magnetic disk 64 is inserted into the magnetic head assembly having the above configuration, as shown in FIG.
The lower magnetic head 52 and the upper magnetic head 54 sandwich the magnetic disk 64 to write and read information, and the relative positional relationship between the magnetic heads 52 and 54 at this time is determined by the leaf hinge spring 55. Retained. Further, when taking out the magnetic disk 64, the lifting protrusion 58 of the arm 53 is lifted by the lifting mechanism, and the arm 53 is moved upward about its base end.

[Problem that the invention attempts to solve]

By the way, the magnetic head assembly as described above includes two magnetic heads 52 and 54, a so-called lower magnetic head 52 on the carriage 51 side and an upper magnetic head 54 on the arm 53 side.
Recording or reproduction can be performed on both sides of the magnetic disk 64. And both magnetic heads 5
The gap position of 2 and 54 is precisely adjusted so that, for example, it is shifted by 4 tracks at 48 TPI and 8 tracks at 96 TPI.
4 compatibility.

At present, when attaching the arm 53 to the carriage 51 in such a magnetic head assembly for double-sided recording, the magnetic heads 52, 54 are attached.
There is a method of tightening the screw 56 while checking the deviation of the gap position (substituted by the core position) using a microscope, and a method of reproducing using a disc for adjusting the gap position, and adjusting the arm 53 so that the reproduction output reaches a predetermined level. Two methods are often used: one is to tighten the screw 56 while adjusting the position of the other. However, in the former method, when adjustment is made without the tension spring 60 attached, when load pressure is applied by the tension spring 60 after adjustment, the leaf hinge spring 55 is deflected, causing an error in the height direction of the arm 53. In addition, in the latter method, adjustment is possible with a predetermined load pressure applied, but the adjustment is made with the leaf hinge spring 55 bent.
This inevitably includes errors in the height direction. Furthermore, in the example shown in FIGS. 4 and 5, since the tension spring 60 is provided at a position close to the proximal end of the carriage 51, a relatively strong elastic force is required to apply a predetermined load pressure. It becomes necessary. This induces deformation of the leaf hinge spring 55,
There is a risk that the error will further increase.

In addition, since the leaf hinge spring 55 is fixed while stress is applied to the leaf hinge spring 55, there is a possibility that the stress applied to the leaf hinge spring 55 is released after the fixation, which may further increase the error. .

This invention was made in view of the problems of the prior art described above, and its purpose is to provide a magnetic head assembly with less arm installation error.

[Means for solving problems]

In order to solve the problems of the prior art and achieve the above objectives, this invention provides a carriage that is equipped with a lower magnetic head and is transported in the radial direction of the recording medium along a guide shaft; an arm that is swingably connected via a leaf hinge spring and has an upper magnetic head mounted at a position opposite to the lower magnetic head; and a load pressure applying means that applies load pressure to the magnetic head against the recording medium. In the magnetic head assembly, the proximal end of the arm body is directly supported by the carriage on the arm attachment side of the carriage, and a load pressure applying means is extended from the carriage side to support the support between the upper magnetic head of the arm and the carriage. The structure is such that the arm is projected toward the carriage between the sections.

[Effect]

According to the above means, the support part on the carriage side directly constitutes the arm instead of the leaf hinge spring.
For example, since the mold member is supported, the rigid bodies come into contact with each other, and the support height is uniquely determined. This eliminates installation errors caused by elastic deformation. Furthermore, since the leaf hinge spring can be attached via the screw with almost no stress applied to it, it is possible to suppress the occurrence of errors due to stress release.

〔Example〕

Embodiments of the present invention will be described below with reference to FIGS. 1 to 3.

Fig. 1 is a sectional view showing an embodiment of the magnetic head assembly according to the present invention, Fig. 2 is a plan view of the main part showing the hinge part between the arm and the carriage, and Fig. 3 is a three-dimensional view of the hinge part. In FIGS. 2 and 3, some parts are omitted to avoid complexity.

In these figures, the magnetic head assembly consists of a carriage 1, an arm 2, a leaf hinge spring 3, etc., and is transported in the radial direction of a magnetic disk 5 along a guide shaft 4 by a pulse motor (not shown).

First, the configuration of the carriage 1 will be described. 6
is the base material of the carriage 1, which is made of insulating synthetic resin. 7 is a head holder attached to the tip of the base material 6, 8 is a lower magnetic head attached to the head holder 7, and 9 is a lower magnetic head 8.
The lead wire is connected to a lead wire 11 for leading out to the outside via a relay terminal 10.
12 is solder, and 13 is an adhesive for fixing the lead wire 11. Reference numeral 14 denotes a mounting bracket installed above the rear end of the base material 6, and a presser plate 15 protrudes from both sides of the distal end of the mounting bracket 14, forming a recess 16 between the mounting bracket 14 and the base material 6. There is.

Next, the configuration of arm 2 will be described. Reference numeral 17 denotes a base material of the arm 2, which is made of insulating synthetic resin.
18 is a gimbal made of a thin metal spring plate attached to the tip of the base member 17, and 19 is an upper magnetic head supported by the gimbal 18. 20 is a lead wire led out from the upper magnetic head 19;
Flexible printed circuit board 21 by solder 12
This flexible printed circuit board 21
is connected by solder 12 to a lead wire 22 for leading out to the outside. Further, this lead wire 22 is fixed at a plurality of locations with an adhesive 13. 23
is a substantially D-shaped support portion formed on both sides of the rear end of the base material 17, and the planarly bulged portion 24 (second
(see figure) is in direct contact with the upper surface of the base member 6 in the recess 16 of the carriage 1, and also faces the lower surface of the presser portion 15 with a slight gap therebetween. 25 is a lifting protrusion for moving the arm 2 upward, and is provided on the side surface of the base material 17.

On the other hand, the leaf hinge spring 3 is made of a single metal plate such as a phosphor bronze plate or a stainless steel plate, and one end of the leaf hinge spring 3 is fixed to the center of the rear end of the base material 17 of the arm 2 with a screw 30 via a metal fitting 29. The other end is attached to the carriage 1 by means of a screw 31 via the mounting bracket 14.
is fixed to. Reference numeral 27 denotes a tension spring interposed between the mounting fitting 29 and a fitting 33 which is adjustable and fixed to the carriage 1 with an adjustment screw 32, and constantly presses the arm toward the carriage 1 side.

In the above configuration, when the magnetic disk 5 is not inserted, the arm 2 is lifted by the lifting protrusion 25 by a lifting mechanism (not shown), and rotates in the direction of the arrow in FIG. 1 about the pair of supports 24. upper magnetic head 1.
9 is spaced apart from the lower magnetic head 8 by a predetermined distance. Further, when the magnetic disk 5 is inserted and clamped, the upward lifting restraint of the arm 2 by the lifting mechanism is released, and the arm 2 is moved by the elastic force of the tension spring 27. The magnetic disk 5 is lowered, and both magnetic heads 8 and 19 sandwich the magnetic disk 5 to write and read information. The relative positional relationship between the two magnetic heads 8 and 19 during this clamping is maintained by the leaf hinge spring 3.

At the base end 2 a of the arm 2 , the planar portion 24 of the support portion 23 , which is the center of rotation, smoothly contacts the R portion 28 of the carriage 1 and performs a hinge function on both sides of the leaf hinge spring 3 in the width direction. , if the arm 2 is suddenly lifted up, the support part 2
6 and the holding portion 15 are in contact with each other, so that excessive bending stress is not generated in the leaf hinge spring 3. Note that the supporting portion 26 is provided with an appropriate radius because it is necessary to maintain a constant gap with the presser portion 15 even during rotation. Further, the arm 2 is lifted via the lifting protrusion 25, but at that time, one side of the leaf hinge spring 3 in the width direction (the lifting protrusion 2
Even if a slight twist occurs due to the height of the arm (the side where the arm 2 is provided), the inclination of the arm 2 around the arm is regulated by the contact between the support part 26 and the support part 15 in the recess 16. Twisting of the leaf hinge spring 3 provided inside the support portion 24 is always suppressed.

When assembling the magnetic head assembly having the above structure, the carriage 1 is attached to the guide shaft 4, and then the upper magnetic head 1 on the arm 2 side is assembled.
9 is placed on the lower magnetic head 8 on the side of the carriage 1, and the proximal support portion 23 of the arm 2 is placed on the R portion 28 of the carriage 1 as a support protrusion.
As a result, the support relationship between the arm 2 and the carriage 1 becomes a support relationship between rigid bodies, and the influence of elasticity is eliminated in the support relationship.

Next, the tension spring 27 is installed between the screw 30 and the metal fitting 30, and the adjusting screw 32 is adjusted to obtain a predetermined load pressure. Adjust the gap spacing as described above. When the adjustment is completed, the mounting bracket 14 is attached to the top side of the leaf hinge spring 3.
The leaf hinge spring 3 is fixed to the upper surface of the base end of the carriage 1 by inserting the screw 31 from the top to the bottom of the mounting bracket 14 and screwing it into the lower mounting bracket 14 in the figure. Therefore, no elastic deformation occurs in the leaf hinge spring 3, and no stress is generated due to the deformation.

As described above, according to the above embodiment, the arm 2 is placed on the carriage 1 and supported rigidly under a preset load pressure, and the gap positions of the magnetic heads 8 and 19 are adjusted. Since the leaf hinge spring 3 can be fixed to the carriage 1 side while maintaining its state, the influence of elastic deformation of the leaf hinge spring 3 can be completely eliminated.

[Effect of idea]

As is clear from the above explanation, according to this invention in which the base end of the arm is directly supported by the carriage and the means for applying load pressure to the arm is provided from the carriage side, the gap position of the upper and lower magnetic heads can be adjusted. can be adjusted under the same load pressure conditions as during recording and reproduction, and there is no risk of the arm mounting position shifting after the arm is mounted, so it is possible to provide a magnetic head assembly with less arm mounting error. Furthermore, this makes it possible to accurately define the gap position, and provides a magnetic head assembly with excellent recording and reproducing characteristics.

[Brief explanation of drawings]

Figures 1 to 3 are for explaining an embodiment of this invention. Figure 1 is a sectional view of the magnetic head assembly according to the embodiment, and Figure 2 shows the hinge portion of the arm and the carriage. Main part side view, 3rd
The figure is a perspective view of the main part showing the leaf hinge attachment part of the arm, Figures 4 and 5 are for explaining the conventional example, Figure 4 is a perspective view of the magnetic head assembly according to the conventional example, Figure 5 is a cross-sectional view of the same essential parts. DESCRIPTION OF SYMBOLS 1... Carriage, 2... Arm, 2a... Base end, 3... Leaf hinge spring, 4... Guide shaft, 8, 19... Magnetic head, 14... Mounting bracket, 23... Support part, 28...R part.

Claims (1)

[Scope of utility model registration request] A carriage is equipped with a lower magnetic head and is transported in the radial direction of the recording medium along a guide shaft, and an upper magnetic head is mounted at a position facing the lower magnetic head and is connected to the carriage via a leaf hinge spring. An arm that can be attached to swing freely,
In a magnetic head assembly equipped with a load pressure applying means for applying load pressure against a recording medium to the magnetic head, the base end of the arm body is directly supported by the carriage on the arm attachment side of the carriage, and the arm is attached to the arm on the carriage side. A magnetic head assembly characterized by being provided with load pressure applying means.