JPH0519227B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION [Detailed Description of the Invention] Technical Field This invention relates to a magnetic head position adjustment device for a magnetic disk device that stores input data on a magnetic disk.

Prior Art Conventionally, as shown in FIG. 1A, as a mounting structure for a magnetic head for writing, reading, or erasing data on a magnetic disk in a magnetic disk device, a pulley 3 fixed to a rotating shaft 2 of a step motor 1 and a magnetic head are used. A configuration in which a magnetic head is fixed to a steel belt 5 stretched between an idler 4 rotatably supported by a frame in a disk device, and a capstan 6 fixed to a rotating shaft 2 as shown in FIG. The magnetic head is fixed to a steel belt 5 wound around the rotating shaft 2, or as shown in FIG. A configuration in which a magnetic head is fixed to a follower 8 that moves in the axial direction is generally known. When adjusting the mounting position of the magnetic head, this was done by appropriately changing the mounting position of the magnetic head with respect to the steel belt 5 or the follower 8 in any of the above configurations. There was a problem that the mounting position could not be adjusted. In particular, in a magnetic disk device in which a high-density magnetic disk is mounted, it is necessary to adjust the position of the magnetic head with extremely high positional accuracy.

Further, in the magnetic disk device shown in FIG. 1c, the rotating shaft of the step motor is rotatably supported with a gap between the inside of the motor housing and the rotor attached to the rotating shaft. As a result, the rotary shaft moves in an arbitrary axial direction with respect to the motor housing, and as a result, there is a problem that the position of the magnetic head with respect to the magnetic disk is not constant.

Purpose of the Invention The purpose of the present invention is to prevent the output shaft of the motor from moving in the axial direction and wobbling with a simple configuration, and to adjust the position of the magnetic head with high precision, in view of the above-mentioned drawbacks of the conventional motor. It is an object of the present invention to provide a magnetic head position adjusting device for a magnetic disk device, which allows a magnetic head to track a disk with high precision.

Example Hereinafter, the present invention will be explained according to one embodiment.

FIG. 2 is a perspective view schematically showing the magnetic disk device according to the present invention, FIG. 3 is a partially cutaway perspective view schematically showing the magnetic disk, and FIGS. 4 and 5 show the internal structure of the magnetic disk device. 6 is a partial sectional view showing the structure of the step motor, FIG. 7 is an explanatory view showing how the follower is attached to the feed screw, and FIG. 8 is a sectional view showing the head holding mechanism.

In the figure, the magnetic disk 9 has a tracking hole 10a in the center thereof into which an output shaft 17 (to be described later) is fitted, and a hub portion 10 in which an engagement groove 10c with a driven portion 10b is formed around the tracking hole 10a. On one or both sides thereof, a disk-shaped magnetic sheet 11 having an index position indicating the head of the track at a position corresponding to the driven portion 10b and storing data is fixed. The magnetic disk 9 is rotatable within a cassette case 12 which has a hole 12a formed at a location corresponding to the hub portion 10 and an elongated head access hole 12b formed at a location corresponding to the track surface of the magnetic sheet 11. It is stored in. The hole 12a in the cassette case 12
A shutter 14 is connected to the inner boss of the head access hole 12b and is connected to an actuating body 13 which is always biased by the elastic force of a helical spring (none of which is shown) when the magnetic disk 9 is not mounted. is rotatably mounted. When the magnetic disk 9 is installed in a magnetic disk device, which will be described later, the shutter 14 moves against the elastic force of the helical spring by coming into contact with a raised piece 49 formed on a cassette holder 43, which will be described later. The head access hole 12b is rotated by the operating body 13 to open the head access hole 12b. In addition, a write-protect detector 56 fixed to the cassette holder 43 is turned on at the front end of the cassette case 12.
An actuating piece 15 is attached so that its position can be changed.

A drive motor 18 having an output shaft 17 oriented in the vertical direction as shown in FIG. 4 is fixed to the frame 16 of the magnetic disk device. The output shaft 17
is rotatably supported on the frame 16 via a bearing 19, and the engagement groove 10c is provided in the upper part of the drawing.
A drive pin 20 that is engaged with the driven part 10b and transmits the rotational driving force of the output shaft 17 to the hub part 10 through contact with the driven part 10b is implanted, and a spindle hub 21 that supports the hub part 10 is fixed. There is. Further, a disk-shaped rotor 22 is fixed to the lower end of the output shaft 17 in the drawing, in which permanent magnets each having different magnetic poles are sequentially arranged in equal parts. and the frame 16
An excitation coil 24 having the same number of magnetic poles as the magnetic poles of the rotor 22 is fixed to a substrate 23 opposite to the rotor 22, and the output shaft 17 is rotated by the excitation drive thereof.

A cover 25 is attached to the rotor 22 to cover its lower end surface and outer peripheral surface, and a permanent magnet 26 for index position detection, which rotates integrally with the output shaft 17, is fixed to a part of the outer periphery of the cover 25. ing. Further, near the rotation locus of the permanent magnet 26, on the substrate 23 corresponding to the driven part 10b, there is a magnetoelectric device that outputs an index detection signal (not shown) based on the magnetic field generated by the proximity of the rotating permanent magnet 26. A Hall element 27 as a conversion element is attached.

A step motor 29 is fixed to the frame 16 and has a rotating shaft 28 as an output shaft in a direction perpendicular to the axis of the output shaft 17. The rotating shaft 2
8 is rotatably supported by a motor housing 30, and a rotor 31 having a large number of pole teeth on its outer periphery is fixed within the motor housing 30. An excitation coil 32 is fixed inside the motor housing 30 along the outer periphery of the rotor 31, and the rotor 31 and the motor housing 3
0, a compression spring 33 is interposed between the rotor 31 and the rotor 31. Also, the right end of the rotating shaft 28 (non-drive side)
An adjustment ring 34 that slides on the outer surface of a bearing 30a constituting a part of the motor housing 30 is attached with a screw 35 so that its position can be changed, so that the rotating shaft 28 can be adjusted appropriately in the axial direction. ing.

A groove 36a is provided on the output side of the rotating shaft 28.
A spirally formed feed screw portion 36 is fixed, and a follower 37 is attached to the feed screw portion 36 along its groove portion 36a. The follower 3
7 has one end having a smaller diameter than the root diameter of the feed screw portion and is wound at least half a circumference, preferably approximately one full circumference as shown in FIG. It is made of an elastically deformable spring wire bent in a direction perpendicular to the axis of the feed screw portion 36 at a position tangentially away from the center by an appropriate width α. The other end of the follower 37 is movable through a guide hole 38a (FIGS. 5 and 7) formed in a guide member 38 that is fixed to the frame 16 and extends parallel to the axis of the feed screw portion 36. At the tip thereof, there is a read/write head that reads data stored on the tracks of the magnetic disk 9 at a position corresponding to the output shaft 17, and also writes data input from an external device, and a read/write head that reads data stored on the tracks of the magnetic disk 9 at a position corresponding to the output shaft 17. A magnetic head 39, which is equipped with an erasing head for erasing stored data, is fixed, and the magnetic head 39 is reciprocated in a direction orthogonal to the axis of the output shaft 17 when the feed screw portion 36 rotates forward or reverse. Further, a track detector 40 is attached to the frame 16, which detects a track (00) by coming into contact with the magnetic head 39 when the magnetic head 39 is moved to the outermost circumferential side of the magnetic disk 9.

The rotating shaft (output shaft of the motor) 28 and the feed screw portion 36 constitute one shaft, and this shaft is connected to the motor housing 30.
It is supported so as to be rotatable relative to it and movable in its axial direction. Further, the adjustment ring 34 and the screw 35 constitute a positioning means.

The drive motor 18 and the step motor 29 are powered by a battery 42 (see FIG. 4) housed in a space formed in the device frame 41, and drive command signals input from an external device (both shown in FIG. (not shown).

The cassette holder 43 is made of an elastic plate material such as a stainless steel plate, and has guide portions 44a, each having a substantially U-shaped cross section, that support and guide both sides of the cassette case 12 when inserting and ejecting the magnetic disk 9. 44b is bent. The one guide portion 44a is in pressure contact with the hub portion 10 of the inserted magnetic disk 9, and the engagement groove 10 is pressed against the hub portion 10 of the inserted magnetic disk 9.
A collet 45 that maintains the engaged state of the drive pin 20 and the drive pin 20 is integrally molded. In addition, the guide portion 4
A coil spring 47 with one end movably supported along the elongated hole 46 is attached to 4a, and the coil spring 47 is pressed when the magnetic disk 9 is inserted, and the spring of the coil spring 47 is pressed when the magnetic disk 9 is ejected. The force causes the magnetic disk 9 to be ejected from the ejection opening 48 formed in the device frame 41. A cut-out piece 49 is formed on the free end side of the guide portions 44a, 44b on both sides, which rotates the shutter 14 by contacting the operating body 13 when the magnetic disk 9 is inserted, thereby opening the head access hole 12b. A pair of arm portions 50 are integrally formed at the base of the cassette holder 43 and are bent so that the free end side of the cassette holder 43 is always positioned at a release position corresponding to the ejection opening 48. A fixing part 51 having a screw hole (not shown) is formed at the rear end of the arm part 50, and is fixed to the device frame 41. On the other hand, as shown in FIG. 5, the free end of the cassette holder 43 has a convex shape formed on the mounting frame 41 when the cassette holder 43 is swung toward the mounting side against the elasticity of the arm portion 50. A pair of locking portions 53 that engage with the hooking portion 52 are integrally bent. Further, as shown in FIG. 4, on the central plane part of the cassette holder 43, an output shaft 17 is installed in the tracking hole 10a of the magnetic disk 9 supported by the cassette holder 43, and a drive pin 20 is installed in the engaging groove 10c. ,
Furthermore, openings 54 are formed to operatively connect the magnetic heads 39 to the track surfaces of the magnetic sheet 11 through the head access holes 12b, and bent supports that abut and support the tip of the inserted and supported cassette case 12 are formed. A plate 55 is integrally formed.

A write-inhibit detector 56 is located on the central plane of the cassette holder 43 and outputs a write-inhibit command signal when it comes into contact with the operating piece 15 attached to the cassette case 12. A cassette detector 57 is fixed to each of the cassette detectors 57, which is turned on by contact with a surface and detects that the magnetic disk 9 is attached.

The magnetic sheet 1 is inserted into a support hole 55a formed in the support plate 55 at a position corresponding to the center of the output shaft 17.
A head pressing member 58 for pressing the magnetic head 39 via the magnetic head 1 is attached. The head pressing member 5
Reference numeral 8 includes a base portion 58a rotatably inserted into the support hole 55a, an arm portion 58b having a pad 59 fixed to the distal end side for pressing the magnetic head 39 via the magnetic sheet 11, and a stopper member. The other arm portion 58c presses against the outer surface of the motor housing 30
and an engaging portion 58d that engages with the tip of the cassette case 12 when the magnetic disk 9 is inserted are integrally formed of an elastically deformable spring member. When the engaging portion 58d of the head pressing member 58 is pressed when the magnetic disk 9 is inserted into the cassette holder 43, the pad 59 is pressed against the surface of the magnetic sheet 11 by the bending of the one arm portion 58b, and the magnetic head 39 is pressed. Press.

In addition, in FIG. 4, 60 is a power switch, 61
62 is an L-shaped, elastically deformable spring member whose base end is fixed to the device frame 41 and whose free end comes into pressure contact with the upper plane of the guide member 44a. When the cassette holder 43 is swung toward the mounting side, a part of the ejection opening 48 is shielded by a closing piece 62a bent at the free end, so that no other magnetic disk 9 can be placed in the magnetic disk device. This is a closing member that restricts insertion.

Next, the operation of this embodiment will be explained with reference to FIG. 9, which shows the mounted state of the magnetic disk.

To attach the magnetic disk 9 to the magnetic disk device, the magnetic disk 9 is inserted through the ejection opening 48 into the cassette holder 43, which is positioned at the release position shown in FIG. 4 due to the elasticity of the arm portion 50.
Both sides of the cassette case 12 are guide parts 44a,
It is supported and guided by 44b. As the magnetic disk 9 is inserted, the actuating body 1 is moved against the cut and raised piece 49.
3 makes contact, the head access hole 12b is opened by the rotation of the shutter 14, and the coil spring 47 is compressed by the contact with the front end surface of the cassette case 12. Further, when the distal end of the cassette case 12 is engaged with the engaging portion 58d due to the insertion of the magnetic disk 9, the head pressing member 58 presses the arm portion 58b according to the pressure of the engaging portion 58d.
The head access hole 1 is opened by bending downward.
The pad 59 is pressed against the magnetic sheet 11 via the pad 2b. Also, the write-protection detector 56 is turned on according to the movement state of the actuating piece 15 attached to the cassette case 12 and outputs a write-protection detection signal, and the cassette detector 57 is turned on when it comes into contact with the tip of the cassette case 12. , outputs a cassette detection signal indicating that the magnetic disk 9 has been inserted to an external device.

In the above state, when the cassette holder 43 is swung to the mounting position shown in FIG. 9 against the elastic force of the arm portion 50, the locking portion 53 is engaged with the latch portion 52, and the mounting state is changed. Retained. Further, the output shaft 17 is fitted into the tracking hole 10a, and the drive pin 20 is engaged with the engagement groove 10c.
The track surface of the magnetic sheet 11 is brought into contact with the magnetic head 39 through the open head access hole 12b, and the pad 59 is pressed against the magnetic head 39.
This maintains the contact between the magnetic head 39 and the track surface. By this operation, the magnetic disk 9 is operatively connected to the drive motor 18 and the magnetic head 39, respectively. When the cassette holder 43 is swung to the mounting position shown in FIG. The magnetic disk 9 is located in a portion of the magnetic disk device to prevent incorrect insertion of the magnetic disk 9 into the magnetic disk device.

Next, in order to detect the index position of the magnetic disk 9 mounted on the magnetic disk device by the above operation, when the drive motor 18 is rotationally driven based on a drive command signal from an external device, the output shaft 17 is rotated.
The drive pin 20 that rotates integrally with the engagement groove 10c
After rotating along the magnetic sheet 10, the magnetic sheet 11 is brought into contact with the driven portion 10b, and the rotational driving force of the drive motor 18 is transmitted to the hub portion 10 to rotate the magnetic sheet 11. The driven portion 10b corresponds to the index position of the magnetic disk 9, and a permanent magnet 26 that rotates integrally with the output shaft 17 is close to a Hall element 27 arranged corresponding to the driven portion 10b. Then, the Hall element 27 outputs an index detection signal based on the magnetic field of the permanent magnet 26, and detects the index position on the magnetic disk 9.

Next, a write command signal input from an external device,
When the step motor 29 is driven based on a read command signal or an erase command signal (none of which are shown), the feed screw portion 36 is rotated integrally with the rotating shaft 28, and the feed screw portion 36 is rotated integrally with the rotation shaft 28. A magnetic head 39 is moved by a follower 37 that moves in the axial direction as the magnetic head rotates. At this time, the rotating shaft 28 is connected to the inner surface of the motor housing 30 and the rotor 31.
Because the elastic force of the compression spring 33 mounted between It is possible to prevent the part 3 from moving in the axial direction and wobbling, and to track the magnetic head 39 with respect to the magnetic disk 9 with high precision. In addition, the follower 37
is wound with one end having a slightly smaller diameter by the root diameter of the feed screw portion 36, is tightened to the feed screw portion 36 in the radial direction, and is installed in a twisted state in which it is elastically deformed along the groove portion 36a, and is wound in the axial direction. Therefore, the magnetic head 39 can be reliably moved in the axial direction without causing backlash when the direction of rotation of the feed screw portion 36 is switched between forward and reverse rotation. Furthermore, since the other end of the follower 37 is bent in a direction perpendicular to the axis at a position tangentially separated by an appropriate width α from the center of the feed screw portion 36, when stress is applied to the other end, , it is possible to disperse stress corresponding to the feed screw portion 36, prevent a decrease in rotational torque in the feed screw portion 36, and move the magnetic head 39 in the axial direction with substantially uniform torque.

When writing data input from an external device, reading data written on the magnetic disk 9, or erasing data written on the magnetic disk 9, at the center position of the output shaft 17 in a direction perpendicular to its axis. The magnetic head 39 is moved to the outermost side of the magnetic disk 9, and the track detector 40
When turned on, the step motor 29 is stopped and the magnetic head 39 is positioned at the track (00). And written in the track (00),
For example, after accessing file data, start position data, etc., a predetermined operation is executed.

Next, in order to adjust the position of the magnetic head 39 in accordance with the track (00) located on the outermost circumferential side of the magnetic sheet 11, the fixed position of the rotating shaft 28 and the adjustment ring 34 on the non-drive side is changed as appropriate. The rotating shaft 28 is moved in an appropriate axial direction by or against the spring force of the compression spring 33,
Move the magnetic head 39. The rotary shaft 28 and the adjustment ring 34 are fixed at the position where the track detection signal is output from the track detector 40 by contact with the magnetic head 39, and the magnetic head 3
Adjust the position in step 9.

Next, in order to eject the magnetic disk 9 from the magnetic disk device, when the locking portion 53 is pushed through the lower part of the ejection opening 48 shown in FIG. 2, the locking portion 53 is disengaged from the latch portion 52. Arm part 50
The elastic force causes the cassette holder 43 to swing back to the release position. Through this operation, the output shaft 17 is disengaged from the tracking hole 10a, the drive pin 20 is disengaged from the engagement groove 10c, and the magnetic disk 9 is removed from the ejection opening 48 by the spring force of the coil spring 47. Automatically eject the magnetic disk to the outside of the device. When the engagement portion 58d of the head holding member 58 and the distal end portion of the cassette case 12 are disengaged from each other during ejection, and the arm portion 58b is returned to its original position, the pad 59 is pressed against the magnetic sheet 11. is canceled. Further, when the contact between the cut and raised piece 49 and the actuating body 13 is released as the magnetic disk 9 is ejected, the actuating body 13
It is returned to its original position by the elastic force of the spiral spring, and the head access hole 12b is closed by the rotation of the shutter 14.

Therefore, in this embodiment, by appropriately changing the fixed position of the adjustment ring 34 on the non-driving side of the rotating shaft 28, the axial length of the rotating shaft 28 on the driving side can be varied, and the mounting position of the magnetic head 39 can be adjusted with high precision. It is possible to adjust the position.

It is installed between the motor housing 30 and the rotor 31, and the rotation shaft 28 is always urged toward the drive side by the elastic force of the compression spring 33. Therefore, when the step motor 29 is driven, the motor housing 30
The rotary shaft 28 is prevented from moving in the axial direction and wobbling, and the magnetic head 39 can be tracked with high accuracy with respect to the magnetic disk 9.

In addition, in the present invention, a single helical groove is formed on the non-drive side of the rotating shaft, and the adjustment member that is engaged with the groove is fixed by a fixing screw, and the adjustment member that rotates along the groove allows the adjustment member on the drive side to be fixed. It is also possible to implement a configuration in which the mounting position of the magnetic head is adjusted by moving and adjusting the axial length of the rotating shaft with high precision.

Effects of the Invention As explained above, the present invention includes a shaft which is composed of an output shaft of a motor and a feed screw portion, and which is movably and rotatably supported in the axial direction of the output shaft with respect to the motor housing; A magnetic disk device comprising: a follower connected to the feed screw portion to convert rotational movement of the shaft into linear movement along the axial direction of the shaft; and a magnetic head connected to the other end of the follower. a spring member provided between the motor housing and the rotor inside the motor housing and biasing the shaft in one direction with respect to the motor housing; and a spring member that moves in the axial direction with respect to the shaft protruding to the outside of the motor housing. an adjustment ring that is movably supported and that abuts against the outer surface of the motor housing to move the shaft against the biasing force of the spring member; and a screw that fixes the adjustment ring to the shaft in a changeable position. This prevents the output shaft of the motor from moving in the axial direction and wobbling, and the position of the magnetic head can be adjusted with high precision, allowing the magnetic head to track with respect to the magnetic disk with high positional precision. It has advantages.

[Brief explanation of the drawing]

1A to 1C are explanatory diagrams showing a conventional example, FIG. 2 is a perspective view schematically showing a magnetic disk device according to the present invention, FIG. 3 is a partially cutaway perspective view schematically showing a magnetic disk, and FIG. 5 and 5 are explanatory diagrams showing the internal structure of the magnetic disk device, FIG. 6 is a partial sectional view showing the structure of the step motor, FIG. 7 is an explanatory diagram showing how the follower is attached to the feed screw, and FIG. 9 is a sectional view showing the head holding mechanism, and FIG. 9 is an explanatory view showing the state in which the magnetic disk is mounted. In the figure, 28 is a rotating shaft as an output shaft, 29 is a step motor, 30 is a motor housing, 33 is a compression spring as a spring member, 34 is an adjustment ring as an adjustment member, 36 is a feed screw, 37 is a follower, and 39 is a It is a magnetic head.

Claims (1)

[Scope of Claims] 1. A shaft that is constituted by an output shaft of a motor and a feed screw portion and is movably and rotatably supported in the axial direction of the output shaft with respect to the motor housing; A magnetic disk device comprising: a follower connected to the shaft for converting rotational movement of the shaft into linear movement along the axial direction of the shaft; and a magnetic head connected to the other end of the follower; a spring member provided between the motor housing and the rotor and biasing the shaft in one direction with respect to the motor housing; and a spring member supported movably in the axial direction with respect to the shaft protruding outward from the motor housing. , an adjustment ring that comes into contact with the outer surface of the motor housing to move the shaft against the biasing force of the spring member, and a screw that fixes the adjustment ring to the shaft so that its position can be changed, the adjustment ring and 1. A magnetic head position adjusting device for a magnetic disk device, characterized in that the position of the magnetic head is adjusted by moving and adjusting the shaft in the axial direction using a screw.