JPH01296471A - Head moving device - 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] The head moving device of the present invention will be explained according to the following items.

A. Industrial field of application B9 Overview of the invention C. Prior art a - Background for boat fishing b. An example of a conventional spatula F 8 motion device [Fig. 10] D. Problems to be solved by the invention [Fig. 10] E. Problems to be solved by the invention Means for solving the problem F Example [Figures 1 to 9] F-1 First embodiment [Figures 1 to 6] a Magnetic disk cassette [Figures 1 and 3 b Magnetic disk Driver [Figs. 1 to 6 b-i Disk drive section, cassette carrier [Figs. 1, 3] b-2, to/from moving device [Figs. 1 to 6 b-2' -a, base [Figs. 1 to 5] 1) -2-b Coarse movement motor, reed flute [Figs. 1 to 3, Fig. 5] b-2-ρ Rotating lever [1st Figures to Figures 5] b-2-d Electrostrictive effect element [Figures 1, 2, 5, 6] 1)-2-e Displacement of reed flute [Figure 2] b- 2-f Head carriage [Figures 1 and 3] 1]-3 Operation F-2 Second embodiment [Figures 7 to 9] a Fulcrum shaft b Rotating lever C action G Effects of the invention ( A. Field of Industrial Application) The present invention relates to a novel head moving device. Specifically, for example, a head carriage that supports a recording/reproducing head that makes contact with a recording medium such as a magnetic disk to perform recording and/or reproduction on the recording medium and is movably supported in a linear direction; A head moving device comprising a moving means for moving a head, in particular a coarse moving mechanism including a coarse moving motor and a coarse moving mechanism rotated by the motor and engaged with a head carriage, such as a toss screw. It consists of a rotary lever that displaces the lead screw in the axial direction, and a fine movement mechanism that finely rotates the rotary lever.By rotating the sole screw with a coarse movement motor, the head carriage is coarsely moved and finely moved. This is related to a head fan hyper-motion device that finely moves the head carriage by rotating a rotary lever using a mechanism and displacing the lead screw in the axial direction.By devising the support structure of the rotary lever, fine adjustment can be achieved. It is an object of the present invention to provide a novel head moving device that operates smoothly and can control the head position with high precision.

(B. Summary of the Invention) The head 8 moving device of the present invention includes a head carriage that supports a recording/reproducing head and is movable in a linear direction, a coarse movement motor, and a head carriage that is rotated by the coarse movement motor. A coarse movement mechanism consisting of an engaged lead screw, etc., a rotating lever that contacts one end of the above-mentioned toss screw and displaces the sorting screw in its axial direction by rotating, and the rotating lever. Equipped with a fine movement mechanism that rotates the lead screw finely, the lead screw is coarsely moved by rotating the lead screw with a coarse movement motor, and the lead screw is displaced in the axial direction by rotating the rotation lever with the fine movement mechanism. In a head moving device designed to slightly move the front and back carriage, the rotation support of the rotation lever is made movable, and by making the rotation support of the rotation lever movable, The part of the rotary lever that is in contact with one end of the lead screw is prevented from moving in a direction crossing the axial direction of the lead screw, thereby smoothly making slight movements in the axial direction of the lead screw, In addition, the head position can be controlled with high precision.

(C Prior Art) (a - Background of Boat Fishing) For example, a recording/reproducing device such as a 611 disk driver has a recording/reproducing device that faces a recording medium such as a magnetic disk and performs recording and/or reproduction on the recording medium. A head carriage supporting the head is provided, and such a head carriage is usually supported so as to be movable in a straight line, that is, in a direction across tracks of a magnetic disk, etc., and is also provided with a moving mechanism driven by a motor. It is now moved by

There are various types of such moving mechanisms, which include a motor and a lead screw rotated by the motor and engaged with a part of the head carriage. Some motors move the head carriage by rotating the motor, and for example, a so-called stepping motor is often used as the motor.

By the way, in order to increase the recording density of a recording medium such as a magnetic disk, it is necessary that the recording medium itself has a quality suitable for high-density recording, and the operation of the recording and reproducing equipment, especially the head moving device. A moving mechanism that can control the position of the head carriage with high precision is required.

In this case, if the stepping motor and lead screw are used as the movement mechanism, is it possible to reduce the rotation pitch of the stepping motor as much as possible? There are certain limits to what you can do.

(b. An example of a conventional spatula 1 moving device) [Figure 10] Therefore, in order to improve the precision of position control of the head carriage, the head carriage is moved by two moving mechanisms, a coarse movement mechanism and a fine movement mechanism. For example, Japanese Patent Application No. 62-204334 and Utility Model Application No. 16754-1987 show such a head moving device.
There is a 6th bulletin.

FIG. 10 schematically shows a head moving device a described in Japanese Utility Model Application No. Sho 62-167546.

In the figure, b is the guide shaft c1. : A bed carriage supporting a recording/reproducing head e which is movably supported and comes into contact with and away from a magnetic disk d. f is the base of the head moving device a, and a coarse movement motor g and a fine movement motor h are fixed to this base f, and at a position opposite to these motors g and h, there is a rotatable intermediate portion of a rotary lever i. and the pivot lever 1
is always biased by a tension spring J with a rotational force that tends to move toward one rotational end toward the coarse movement motor g. K is a lead screw that is engaged with a part of the head carriage b and is arranged so as to extend parallel to the moving direction of the head carriage b;
A spring (not shown) is brought into contact with a receiving part C provided at one rotating end of the spring, and the other end is used as a rotor shaft of a coarse movement motor g, and has an elastic force smaller than the tensile force of a tension spring J (not shown). It is constantly pressed toward the rotating lever 1 side by the resilient means. m is a string-like member formed by fixing both ends of two wooden wires n and n' together by fixing members 0 and p, respectively, and one of the fixing members 0 is integrally formed with a hook q, The hooking piece q is rotatably locked to a reference shaft r provided upright at the other rotating end of the rotating lever 1, and the other fixed member p is connected to the rotating shaft S of the fine movement motor h. The two wires n and n' are twisted appropriately so that they are intertwined with each other when the head carriage b is at the origin of movement.

Therefore, the rotating lever i is not pulled toward the motor g, 1 by its two rotating ends, the string member m, and the tension spring j, and the string member m is pulled toward the motor g, 1 by the string member m and the tension spring j. Since the length is changed by increasing or decreasing the amount of twist, the length of the string member m increases by one return amount, and the length of the string member m becomes shorter. The other rotating end of the rotating lever j is pulled, and the rotating lever 1 is rotated in the counterclockwise direction in the figure.
When the string-like member m is twisted back, the length of the string-like member m becomes longer, and as a result, the string-like member m is rotated clockwise in the figure by the tensile force of the rotating lever 1 or the tension spring J. That will happen. When the rotary lever 1 is rotated in the counterclockwise direction, the lead screw k or the spatula L-carriage b is moved integrally with the motor g, and when the rotary lever 1 is rotated in the clockwise direction, head carriage b
It will be moved integrally to the motor g side.

When the coarse movement motor g rotates, the screw k also rotates, causing the head carriage b to move coarsely, and depending on this coarse movement, the position of the recording/reproducing head e or the target on the magnetic disk d may be changed. If the sharpening does not match the position of the track to be used, the fine movement motor h rotates and twists or returns the string member m, thereby tightening the lead screw k.
is moved in its axial direction to slightly move the head gear ridge b.

(D. Problem to be solved by the invention) [Fig. 10] In the conventional head moving device a shown in Fig. 10,
Since the pivot point t of the pivot lever 1 is fixed to the base f, there are problems in that it is difficult to operate smoothly and the accuracy is not good.

That is, when the rotary lever 1 is rotated, the portion U of the rotary lever i where one end is in contact with the lead screw, or
As shown in FIG. 10, it moves while drawing a circular arc of radius R. Therefore, there is a distance I between one end W and the side of the lead screw.
f! However, since the lead screw is supported by a bearing, it cannot move laterally at all. Therefore, there is a positional deviation of a distance 1alID between one end W of the lead screw and the abutment part U of the rotating lever 1, and this positional deviation is forced, so that the rotating lever 1 is The rotational movement, that is, the slight movement of the lead screw, is no longer smooth. In addition, the slippage between the one end W of the lead screw and the abutting part U of the rotary lever 1 may cause the scale to lose its accuracy, or the rotation may be caused by repeating such positional misalignment. There is also the problem that the accuracy deteriorates significantly as the lever 1 is used, as the abutting portion U of the lever 1 is warped and one end W of the lead screw is severely worn.

(E. Means for Solving the Problems) Therefore, in the uninvented head moving device, the pivoting fulcrum of the pivoting lever is made movable.

Therefore, in the head moving device of the present invention, when the rotary lever rotates and almost comes to a position where one end of the lead screw and the rotary lever come into contact, the rotary fulcrum portion is moved to that position. Since the lead screw moves in a direction that absorbs the slippage, no unreasonable force is generated between one end of the lead screw and the abutting part of the rotary lever. This has the advantage that small movements can be made smoothly and the head position can be controlled with high precision.

(Embodiment F) [Figures 1 to 9] Details of the motion device of the present invention will be described below according to the illustrated embodiments.

In each of the illustrated embodiments, the present invention is applied to a head moving device in a magnetic disk driver.

(F-1 First Embodiment) [Figures 1 to 6] First, an example of a magnetic disk cassette will be explained, and then a magnetic disk driver will be explained.

(a Magnetic tape cassette) [Figures 1 and 3] 1 is a magnetic tape cassette.

Reference numeral 2 is a thin box-shaped cassette case, and a circular hole 4 is formed approximately in the center of one of the two wall portions 3.3' facing each other in the thickness direction. A head insertion hole 5.5' is formed on one side of the head insertion hole 5.5', and the head insertion hole 5.5' is used as a shutter (not shown) when the head insertion hole 5.5' is not installed in the magnetic disk casera 1 to 1 or the magnetic disk driver described later. It is blocked by.

Reference numeral 6 denotes a magnetic disk in the form of a thin sheet, which is rotatably housed in the cassette case 2. A center core 7 is attached to the center of the disk, and the center core 7 has a main engagement hole 7a and a driven hole. 7b is formed, and this center core 7 is located so as to face the outside from the center hole 4 of the cassette case 2.

(b, 6n disk driver) [Figures 1 to 6] 8 is a 6n disk driver, and 9 is its mechanical chassis.

(b-1 disk drive unit, cassette carrier) [Figures 1 and 3] 10 is the front end of the Nuka chassis 9 (the direction to the left in Figure 1 is the front side, and the direction to the right is the rear side) (In addition, the upward direction in the same figure is the left side, and the downward direction is the right side. In the following explanation, directions will be referred to in this direction.) Discs placed at closer positions Drive motor (only a portion is shown in the drawing).

), a rotating plate 12 is fixed to the upper end of the rotating shaft 11, and a driving bin 13 is provided protruding from the rotating plate 12.

Reference numeral 14 denotes a cassette carrier supported so as to be vertically movable by guide means (not shown) provided on the core chassis 9, into which the magnetic disk cassette 1 is removably inserted, and the magnetic disk cassette 1 is moved to a predetermined insertion position. Once inserted, it is moved to the mounting position shown by the solid line in FIG. When the cassette carrier 14 comes to the mounting position, the center core 7 of the magnetic disk 6 of the magnetic disk cassette 1 is mounted on the rotating plate 12, and one of the rotating shafts 11 of the motor 1o is inserted into the engagement holes 7a, 7b. The driving pins 13 are individually engaged with the portions projecting upward from the rotary plate 12, whereby the magnetic disk 6 and the rotary plate 12 are rotated integrally.

(b-2, Head moving device) [Figures 1 to 6] 15 is a head moving device, which includes a base fixed to the mechanical chassis 9, a coarse movement motor fixed to the base,
A lead screw rotated by a coarse movement motor, a rotary lever rotatably supported on a base and in contact with one rotary end or the opposite end of the lead screw, and the other rotary lever. It supports an electrostrictive effect element, which is a fine movement mechanism, connected between the end portion and the base, and a magnetic head that contacts and separates from the magnetic disk, and is supported by the mechanical chassis 9 so as to be freely movable in the front and rear directions. It consists of a head carriage etc. that are engaged with one screw.

(b-2-a, base) [FIGS. 1 to 5 16 is the base. Reference numeral 17 denotes the main part of the base 16, which has a substantially rectangular plate shape long in the front-rear direction, and is integrally formed with a substantially rectangular motor mounting wall 18 long in the left-right direction at its rear end. A screw support wall 19 is erected at a position slightly rearward from the front end of the left end, and is connected to the right end of the screw support wall 19 by a motor mounting wall 18 or a reinforcing wall 20.

Reference numeral 21 denotes a spring piece protruding leftward from a position near the rear end of the left end surface of the main part 17, and reference numeral 22 denotes a piece of wood protruding upward from a position diagonally forward to the right of the screw support wall 19 of the main part 17. 23 and 23' are holes formed in the main portion 17, and 24 is a notch for fixing the position.

Further, reference numeral 25 denotes a support portion projecting rightward from the rear end portion of the main portion 17, and a support shaft 26 is erected from the support portion 25.

The base 16 is either the main part 17 or the mechanical chassis 9.
The base mounting portion 27, 27 provided on the top surface of...
(Only two are shown in the drawing.) The screws 28.28 are placed on top and inserted through the mounting holes 23.23'.
The screws 28' engaged with the notches 24 are fixed to the mechanical chassis 9 by being screwed onto the base mounting portions 27, 27, . Positioning walls 27a, 27 raised from 27
a (see Figure 1). In this way,
The base 16 is positioned relative to the mechanical chassis 9.

(b-2-b, coarse movement motor, lead screw) [Figs. 1 to 3, Fig. 5] 29 is a coarse movement motor.

30 is a casing of the coarse movement motor 29, which has a short cylindrical shape in the axial direction, has a flange 30a formed at its front end, and has an insertion hole 30c in the center of the front plate 30b.
Moreover, a spring groove 431 is formed in the center of the rear face plate 30d in the shape of an inward cut.

32 is a stator attached to the inner peripheral surface of the casing 30.

Reference numeral 33 is a cylindrical or toss screw, and a spiral groove 34 is formed in the portion excluding the front end 33a and the rear one-third portion 33b, and hemispherical recesses 3 are formed on both the front and rear end surfaces.
3c, 330' are formed, and the rear recess 33C'
A sphere 35 is fixed to the.

Reference numeral 36 denotes a bearing placement hole formed approximately at the center of the screw support wall 19 of the base 16, and a bearing 37 is press-fitted into the bearing placement hole 36.

38 is the bearing 3 of the motor mounting wall 18 of the base 16.
It is an insertion hole formed at a position facing 7, and its rear part 38a is formed in a large diameter, and the portion 38 formed in the large diameter
A pole bearing 39 is fixed to a.

The lead screw 33 is rotatably and slidably supported by a front end 33a or a bearing 37 of the screw support wall 19, and a part near the rear end or a pole hair ring 39 of the motor mounting wall 18. Further, the flange 30a of the casing 30 is fixed to the rear surface of the motor mounting wall 18 in a coaxial state with the beam screw 33.

A rotor 40 is externally fixed to a portion of the word screw 33 that protrudes into the casing 30, and the rotor 40 and the stator 32 constitute a stepping motor.

When a driving current is supplied to the stator 32, rotational force is applied to the rotor 40, which causes the lead screw 33 to rotate.

As will be explained in detail later, the lead screw 33 is pushed forward by the resilient piece 31 of the casing 30, and is also pushed backward by a rotating lever, which will be described later. The pressing force is maintained at a balanced position.

(b-2-c Rotating lever) [Figures 1 to 5] 41 is a rotating lever.

The rotary lever 41 has a plate shape long in the left-right direction, and its left and right ends 41a and 41b are located slightly below the remaining parts. A notch 42 is formed at the front edge of the left end 41a, and a mounting hole 43 is formed at the center of the right end 41b. In addition, there is a mounting hole 44 in the center.
is formed.

45 is the number hole 44 of the rotating lever 4 and the left end portion 41a.
It has a cylindrical shape extending in the front-back direction, and a circular recess 46 on the rear surface.
A screw hole 4 is formed between the recess 46 and the front end surface.
7 is formed, (1 is.

Reference numeral 48 denotes a bipot 1-bearing which is fitted inside the four parts 46. The support body 48a is shaped like a thick disk and has a concave portion opened on the rear surface, and the support body 48a is shaped like a plate and has an opening on the rear surface. The retainer ring 49 is supported in the portal, an annular retainer ring 50 is arranged to close the opening surface of the retainer ring 49, and the retainer ring 49 is arranged and held in a space between the retainer ring 49 and the retainer ring 50 so as to be freely removable. A large number of spheres 51.51,...
It consists of

52 is an adjustment screw screwed into the screw hole 47 of the bearing fq section 45.

Reference numeral 53 denotes a fulcrum arm, which is formed into a balk shape at its rear half so as to form a substantially U-shape when viewed from the side. The support shaft 22 erected from the base 16 is inserted into the supported hole 54 formed at the front end of the fulcrum arm 53, so that the fulcrum arm 53 is rotatably supported by the base 6. Ru.

55 is a shaft installed between the balk component pieces 56 and 56 of the fulcrum arm 53, and the shaft 55 is installed in the mounting hole 44 of the rotary lever 41 located between the balk component pieces 56 and 56.
This allows the rotary lever 41 to be rotatably supported by the rear end of the fulcrum arm 53.

In this way, the pivot lever 41 is rotatably supported by the base 16 via the fulcrum arm 53.

The rotary lever 41 has a notch 42 at its left end 41a.
A tension spring 57 stretched between the base 16 and the spring tree piece 21 constantly applies a rotational force in the clockwise direction in FIG.
Rotation in the above direction is regulated by an electrostrictive element, which will be described later, which is connected between the supporting part 25 of the tension spring 57 and the tension spring 57.
It is rotated in the counterclockwise direction against the tensile force of the tension spring 57, or it is rotated in the counterclockwise direction by the tensile force of the tension spring 57.

(b-2-d Electrostrictive Effect Element) [Figures 1, 2, 5, 6] 58 is an electrostrictive element that constitutes the fine movement mechanism. When a voltage is applied to the electrostrictive effect element 58, it generates a strain corresponding to the amount of the applied voltage. It is known that it has a capacitor structure and generates large distortion at low voltage. Regarding the electrostrictive effect element having such a structure, for example,
It is not shown in Publication No. 355.

This electrostrictive effect element 58 has a prismatic appearance, and 59
．． Reference numeral 59' denotes a liner for applying voltage to Jl, and is connected to a control circuit (not shown). When a voltage is applied to this electrostrictive element 58, a large strain is generated in its longitudinal direction.

Reference numeral 60 and 60' denote a connecting device, which has a substantially U-shape when viewed from the side. That is, connecting pieces 62, 62 and 62',
It has a shape that protrudes in the same direction as 62'. and,
Each connecting piece 62, 62', 62' has a connecting hole 63.
．． 63, 63', and 63' are formed.

Each connector 60, 60' is fixed to both ends of the electrostrictive element 58. That is, the front end surface of the electrostrictive element 58 is fixed to the surface of the connector 60 on the side opposite to the connecting piece 62, 62 of the intermediate piece 610 by means of fixing means such as adhesive, and the rear end surface of the electrostrictive element 58 is fixed to the front end surface of the electrostrictive element 58. The surface of the intermediate piece 61' of the connector 60' on the side opposite to the connecting pieces 62' and 62' is fixed by adhesive or the like.

As a result, connecting pieces 62, 62, 62', and 62' protrude from the upper and lower ends of both end faces of the electrostrictive element 58, respectively.

Therefore, the rotary lever 4 is placed between the front connecting pieces 62 and 62.
1, the right end portion 41b of the connecting piece 62, 62 is aligned with the connecting hole 63, 63 of the connecting piece 62, 62, and these are rotatably connected by the mounting pin 64. As a result, the front end of the electrostrictive element 58 or the right end 4 of the rotating lever 41
It is rotatably connected to 1b. In addition, the rear connecting piece 62
A support shaft 26 erected from a support portion 25 provided at the rear of the base 16 is rotatably inserted into the connecting holes 63' and 63' of the base 16, and thereby the rear of the electrostrictive element 58 is inserted. The end is rotatably supported on the base 16.

(b-2-e. Displacement of the lead screw) [Fig. 2] As mentioned above - 1 - The screw 33 is a sphere 35 fixed to the four parts 33C' formed on the rear end surface (J) Casing of the coarse movement motor 29 30 and is pressed forward by the resilient piece 31, and the four parts 33c formed on the front end surface thereof.
The axial position of the ball 65 is determined by the ball 65 disposed in the rotary lever 41 being in rollable contact with the multiple balls 51, 51, . . . of the pivot bearing 48 supported by the pivoting lever 41 ing.

When the voltage applied to the electrostrictive element 58 changes to decrease the length of the electrostrictive element 58 and the length of the electrostrictive element 58 becomes short, the right end 41 of the rotary lever 41
b is pulled rearward, so the lead screw 33 is rotated in the counterclockwise direction against the tensile force of the rotating lever 41 or the pulling spring 57, thereby causing the lead screw 33 to release the resilient piece 31 of the casing 30. It will be moved forward by the pressing force.

Further, the voltage applied to the electrostrictive element 58 is changed to increase the length of the electrostrictive element 58, so that the electrostrictive element 5
8 becomes longer, the rotation lever 41 or the tensile force of the tension spring 57 rotates clockwise by an amount corresponding to the increased length, and the pivot bearing 48 and the screw 33 are pushed backward. As a result, the lead screw 33 is moved backward against the pressing force of the resilient piece 31 of the casing 3o.

Then, when the rotating lever 41 rotates and the pivot bearing 48, which is the abutting part that is in contact with the sphere 65, which is one end of the lead screw 33, tries to move sideways from the axis of the lead screw 33. Since a force acts between the sphere 65 of the lead screw 33 and the pivot bearing 48 to keep them in contact with each other, the fulcrum arm 53 rotates, and the shaft serving as the fulcrum of the rotation lever 41 rotates. 55, the lead screw 33 can be smoothly displaced in the axial direction, and since the pivot bearing 48 is always positioned on the axis of the lead screw 33, highly accurate adjustment can be performed.

(b-2-f head carriage) [Figures 1 and 3] 66 is a head carriage. The head carriage 6
Reference numeral 6 denotes a movable support 67 having a substantially left-sideways tilted shape when viewed from the right side, a head arm 68 hinged to the rear end or the upper surface of the rear end of the movable support 67, and a movable support. A magnetic head 70, 70' for recording and reproducing is attached to the mutually opposing surfaces of the distal end of the movable support 67 and the head arm 68. .

Reference numeral 71 denotes a kite shaft that is spaced to the left from the head movement device 15 and is arranged to extend along the front-rear direction, and the support member 7 has both ends fixed to the mechanical chassis 9.
2.72.

The head carriage 66 is slidably supported by its supported portion 69 on the kite shaft 71, and is connected to an engagement pin 73 that protrudes from the rear end of the movable support 67 toward the right. The sorting screw 33 is sandwiched from above and below by the plate spring pieces that do not have the same shape, and the engaging pin 73 is engaged with the lead screw 33 by being engaged with the helical groove 34 formed in the lead screw 33.

Therefore, the head gear ridge 66 is connected to the lead screw 3.
3 rotations and the engagement pin 73 is pressed in the front-back direction, thereby moving the engagement pin 73 in the front-back direction, or by displacing the lead screw 33 in the above-mentioned direction, the engagement pin 73 is moved in the front-back direction integrally with the lead screw 33. ].

Incidentally, while the head arm 68 is not at the loading position of the cassette carrier 14, there is a predetermined gap between the head arm 68 and the magnetic head 70' or the magnetic spatula (70), as shown by the lines 23p and Ql in FIG. They are placed on standby at positions facing each other from above with a gap between them.

(B-3 Operation) Therefore, when the magnetic disk 6 of the 6n disk cassette 1 is attached to the rotary plate 2 of the disk drive motor 10, the magnetic head 70 supported by the movable support 67 The head arm 68 is in relative contact with the lower surface and in conjunction with the downward movement of the cassette carrier 14.
Then, the magnetic spatula F 70 ′ supported by the head arm 68 is brought into contact with the upper surface of the magnetic disk 6 .

When a recording or reproducing operation is started, the magnetic disk 6 is rotated and the head carriage 66 or the magnetic head 70 or 70' is moved to a position facing a designated track on the magnetic disk 6. .

The head carriage 66 is moved by first rotating the coarse movement motor 29 or the lead screw 33, and this movement causes the magnetic head 70 or 70' to move.
When the magnetic head 70 or 70' faces a designated track, that is, when the magnetic head 70 or 70' detects the designated track, it immediately starts recording or recording signals without changing the voltage applied to the electrostrictive element 58. Reading is started, and if the magnetic head 70 or 70' is not facing the designated track during movement by rotating the lead screw 33, the voltage applied to the electrostrictive element 58 is moved in the designated direction. The track is changed depending on whether the magnetic head 70 or 70' is currently on the ascending side or the descending side with respect to the opposing track. By rotating the lead screw 33 in the clockwise or counterclockwise direction to move the lead screw 33 in the front-back direction, the head carriage 66 is slightly moved in the front-back direction, that is, in the tracking direction. Controlled to face the specified track.

(F-2 Second Embodiment) [Figures 7 to 9] Figures 7 to 9 show a second embodiment 15A of the spatula and moving device of the present invention.

The only difference between this second embodiment 15A and the first embodiment 15 is the pivot point of the pivot lever.
Since the other parts are the same as those in the first embodiment 15, only the different parts will be explained in detail, and the same parts will be referred to by the reference numerals given to the similar parts in the first embodiment 15. The same reference numerals will be used to omit the explanation.

(a Fulcrum shaft) Reference numeral 74 is a fulcrum shaft erected approximately at the center of the front end portion of the main portion 17 of the base 16, and is composed of a base and a head attached to the upper end of the base.

75 is a base, and the upper end is a cylindrical sliding contact part 76 having a smaller diameter than the rest of the base, and the sliding contact part 76 has a screw hole 77 opened at its upper end surface. .

Reference numeral 78 has a head having a diameter larger than that of the sliding contact portion 76 of the base portion 75, and a screw shaft 79 extending vertically from the center of the lower surface thereof is screwed into a screw hole 77 of the sliding contact portion 76.

(b Rotating Lever) A sliding hole 80 extending in the longitudinal direction is formed in the center of the rotating lever 41A. The width of the sliding hole 80 is formed to be approximately the same as the outer diameter of the sliding contact portion 76 of the fulcrum shaft 74. Further, the thickness of the portion of the rotating lever 41A where the sliding hole 8o is formed is approximately the same as the height of the sliding contact portion 76 of the fulcrum shaft 74.

Therefore, the fulcrum shaft 74 is inserted into the sliding hole 8o of the rotating lever 4jA.
By attaching the head 78 to the base 75 while passing through the sliding contact portion 76 of the base 75, the rotary lever 41A is rotatably and slidably supported on the fulcrum shaft 74. That is, the pivot portion of the pivot lever 41A is movable within the range of the sliding hole 8o with respect to the pivot lever 41A.

(C effect) Therefore, even if this second embodiment 15A is not satisfied, even if the rotation of the rotation lever 41A causes the ball 65 at the tip of the sorting screw 33 and the pivot bearing 48 to become misaligned, Since the rotating lever tlA slides relative to the fulcrum shaft 74 in a direction that absorbs the positional deviation, the sphere 65 and the pivot bearing 48 are always in contact with each other on the axis of the lead screw 33.

(G. Effects of the Invention) As is clear from the above description, the head moving device of the present invention includes a head carriage that supports a recording/reproducing spatula and is supported by a chassis so as to be movable in a straight line, and A coarse movement motor is fixed to the coarse movement motor, and a rotation motor is provided on the chassis so as to be displaceable in substantially the same direction as the direction of movement of the head carriage on both sides of the fulcrum part and located apart from the coarse movement motor. When it comes into contact with the lever and one end of the rotating lever, it is elastically biased towards the rotating lever and a part of the head carriage is engaged and rotated by the coarse movement motor. The head carriage is coarsely moved by rotating the lead screw using a coarse movement motor, and the rotating lever is rotated by a fine movement mechanism. This head moving device is configured to slightly move a head carriage by moving the lead screw in the axial direction, and is characterized in that the pivot point of the pivot lever is movable.

Therefore, in the head moving device of the present invention, when the rotary lever rotates and the end of the lead screw and the rotary lever are about to come into contact with each other, the rotary fulcrum portion is moved to that position. Since it moves in the direction that absorbs the misalignment, no unreasonable force is generated between one end of the lead screw and the abutting part of the rotary lever. It has the advantage that fine movement of the screw is performed smoothly and the head position is controlled with high precision.

In each of the above embodiments, an electrostrictive effect element is shown as a fine movement mechanism, but the gist of the present invention resides in the rotation fulcrum of the rotation lever, and the fine movement mechanism is not limited to the one shown in the above embodiments. However, other things may be used. For example, the fine movement mechanism using the fine movement motor g and the string-shaped portion m shown in the conventional example can also be applied.

[Brief explanation of the drawing]

1 to 6 show a first embodiment in which the head moving device of the present invention is applied to a head moving device installed in a magnetic disk driver, and FIG. 1 is a schematic plan view of the entire magnetic disk driver; Fig. 2 is an enlarged horizontal sectional view of the Hen 81g motion device, Fig. 3 is a sectional view taken along the line III-III in Fig. 1, Fig. 4 is a cut end view taken along the line IV-IV in Fig. Figure 5 is an enlarged perspective view of the 8-head movement device;
The figure is an enlarged perspective view of the fine movement mechanism before it is incorporated into the head 8 movement device, and FIGS. 7 to 9 show a second embodiment of the head movement device of the present invention, and FIG. 7 is a plan view. , Figure 8 is a perspective view, Figure 9 is an exploded perspective view of main parts, Figure 10 is a perspective view.
The figure is a schematic plan view showing an example of a conventional head moving device. Explanation of symbols 9... Chassis, 15... Head moving device, 29... Coarse movement motor, 33... Lead screw, 33a... One end (of lead screw), 41...
... Rotating lever, 41a... One rotating end of the rotating lever, 41b...
The other rotating end of the rotating lever, 55... Rotating fulcrum of the rotating lever, 58... Fine movement mechanism, 66... Hetsu I-carriage, 70.70'... For recording and reproducing. Head, 15A... Head movable neck, 41A... Rotating lever, 80... Rotating fulcrum of rotating lever Applicant: Sony Corporation

Claims (1)

[Claims] A head carriage that supports a recording/reproducing head and is supported by a chassis so as to be movable in a straight line, a coarse movement motor fixed to the chassis, and a head carriage located apart from the coarse movement motor and on both sides of the fulcrum. A rotary lever rotatably provided on the chassis so as to be displaced in substantially the same direction as the moving direction of the rotary lever; A lead screw that is elastically biased and engaged with a part of the head carriage and rotated by a coarse movement motor, and a fine movement mechanism that finely moves the other rotating end of the rotation lever, and a coarse movement motor. A head moving device that coarsely moves a head carriage by rotating a lead screw and finely moves the head carriage by rotating a rotation lever using a fine movement mechanism to displace the lead screw in the axial direction. , a head moving device characterized in that the rotation fulcrum of the rotation lever is movable.