JP2581030B2 - Magnetic disk drive - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a magnetic disk drive, and more particularly to a magnetic disk drive having a mechanism for softly landing an upper magnetic head.

[0002]

2. Description of the Related Art In a conventional magnetic disk drive, as shown in JP-A-54-121712 and JP-A-58-91562, an upper magnetic head provided on a head arm is rapidly mounted. To prevent the upper and lower magnetic heads from being damaged by colliding with the lower magnetic head provided on the carriage.

Japanese Unexamined Patent Publication No. 54-121712 discloses an oil damper provided between a head arm for raising and lowering a magnetic head and a carriage for mounting the head arm. A damper applies a braking force proportional to the descending speed of the head arm directly to the head arm, so that the magnetic head provided on the head arm is soft-landed on the magnetic disk.

Japanese Unexamined Patent Application Publication No. 58-91562 discloses a magnetic disk drive which is provided on a head arm which moves up and down by opening and closing a door provided at a magnetic disk insertion slot, and which has a magnetic disk. A stopper is provided on the eject plate for restricting the upper magnetic head provided on the head arm from contacting the lower magnetic head provided on the carriage when not mounted in the drive device. The stopper locks the head arm and lifts the head arm unless the magnetic disk is mounted in the magnetic disk drive.
In addition, when the magnetic disk is mounted on the magnetic disk drive, it is detached from the head arm and the head arm is lowered.

[0005]

SUMMARY OF THE INVENTION The above-mentioned JP-A-54-121712 is disclosed.
In the configuration disclosed in Japanese Patent Application Laid-Open Publication No. H11-260, the braking arm of the oil damper is directly locked to the head arm having an upper magnetic head and requiring high-precision operation so as to reduce the descent speed of the head arm. ing. For this reason, there is a disadvantage that the oil damper must be of high precision. In addition, Japanese Patent Application Laid-Open No.
In the configuration of Japanese Patent Application Laid-Open No. 121712, a complicated mechanism including a soft arm, a bail, an electromagnet, and the like is required to rotate the head arm. There is a disadvantage that there is.

In the structure disclosed in Japanese Patent Application Laid-Open No. 58-91562, the head arm is moved up and down in conjunction with the rotation of the door. When the door is forcibly opened and closed while locked to the arm, excessive force is applied to the stopper and the head arm, and both of them are deformed and there is a high risk of malfunction, and the two are the stopper and the head arm. When the lock is released, the head arm descends suddenly and the upper magnetic head collides strongly with the magnetic disk, so that there is a high risk of damaging both the upper magnetic head and the magnetic disk.
First, by the clamp arm that interlocks with the opening and closing of the door,
Since the head arm and the center cone for holding the magnetic disk on the spindle are moved up and down, it is necessary to make the dimensions related to the door, the clamp arm, the head arm and the center cone highly accurate. And has the disadvantage of low productivity.

SUMMARY OF THE INVENTION In view of the above drawbacks, it is an object of the present invention to prevent the upper magnetic head and the magnetic disk from being damaged by soft landing of the upper magnetic head on the magnetic disk using a rotary oil damper. An object of the present invention is to provide a magnetic disk drive having a simple structure and excellent productivity.

[0008]

The present invention comprises a chassis,
An eject plate slidably mounted on the chassis so as to move back and forth along the surface of the chassis, and slide in a direction perpendicular to the sliding direction of the eject plate to approach the surface of the chassis. A cassette housing slidably mounted on the chassis so as to be separated from and away from the chassis, and a flat plate-like shape which is inserted into and removed from the cassette housing along the sliding direction of the eject plate, and has a built-in magnetic disk. And a guide member provided on both sides of the cassette storage body, and the guide member is slidably connected to each other, and the eject plate is moved back and forth so as to be close to the surface of the chassis. Are provided on both sides of the eject plate to apply a releasing movement to the cassette storage body. An inclined groove for id member connected, a locking mechanism in which the pushed-in state of holding a cassette inserting the cassette container is released with the eject pushed to the rear side plate is held in a state of being pushed,
Return biasing means provided on the eject plate and returning the ejected plate that has been pushed in by releasing the lock mechanism so as to retreat toward the front side; and a rear position of the chassis passing through the center of the chassis. And a magnetic head means disposed on the lower side of the cassette and having a lower head; and a magnetic head means disposed on the upper side of the cassette and having an upper head. An upper head member rotatably supported; and a head spring provided to apply a force for pressing the upper head to the magnetic disk of the cassette to the upper head member. By moving the cassette housing closer to the surface of the chassis by retreating, the magnetic disk is moved to the lower head of the lower head member. The upper head of the upper head member is pressed by the head spring to abut on the upper surface of the magnetic disk opposite to the lower head and the lower disk, so that the magnetic disk is clamped by the upper and lower heads. A rotary oil damper for braking the sliding movement of the eject plate.

[0009]

When the cassette is inserted into the cassette housing and the cassette is pushed, the lock mechanism is released, and the eject plate is gradually moved toward the front of the chassis by the rotary oil damper. When the eject plate moves, the guide member is pushed downward by the inclined groove, the lock mechanism is released, and the cassette storage body is slowly lowered. With the lowering of the cassette housing, the upper head member of the cassette housing is also slowly lowered, and the upper head soft-lands on the magnetic disk.

[0010]

BRIEF DESCRIPTION OF THE DRAWINGS FIG.
explain. 1 to 4, 1 is a chassis, 2 is an eject plate, and 3 is a guide roller (guide member) on a side surface.
And a cassette 4 containing a magnetic disk. 5 is a release plate, 6 is a contact portion of the release plate 5, 7 is a claw of the release plate 5, 8 is an upper head arm (upper head member) provided at a rear portion on the chassis 1, and 9 is a lower surface of the upper head arm 8. Upper magnetic head (upper head) provided at 10
Denotes a projection provided at the rear of the eject plate 2. The release mechanism 5, the contact portion 6, the claw 7, and the protrusion 10 constitute a lock mechanism. 11 is a rotary oil damper, 12 is a pin of the rotary oil damper 11, 13 is an inclined groove provided on the side of the eject plate 2, and 14 is a vertical guide groove provided on the side of the chassis 1. The guide roller has a mechanism in which the guide roller is slidably fitted in the vertical guide groove 14 and also fitted in and connected to the inclined groove 13. Reference numeral 15 denotes a projecting portion provided at a front portion of the eject plate 2, and 16 denotes a return spring (return biasing means) provided between the chassis 1 and the eject plate 2, which pushes the eject plate 2 toward the front side. Act on. Reference numeral 17 denotes a seat provided at the rear of the cassette housing 3, reference numeral 18 denotes a rear end of the cassette 4, reference numeral 19 denotes a square hole provided at the protruding portion 15, and reference numeral 20 denotes an eject button provided at the front of the eject plate 2. Seat 1
The spring force of the head spring for pressing the upper head arm 8 always acts on 7.

A magnetic head device including an upper magnetic head 9 and an upper head arm 8 will be described. The magnetic head device is provided at a position on the inner side of the chassis 1 that passes through the center of the chassis 1. The magnetic head device includes an upper head member having an upper magnetic head 9 at a lower end of an upper head arm 8 and a lower head member having a lower magnetic head 9 '(lower head) at a lower end of a lower head arm 8'. Is provided. The upper head member has a rear end side supported by the chassis 1 so as to rotate in the vertical direction, and has a head spring 8a for pressing the upper magnetic head 9 against the magnetic disk. The upper magnetic head 9 comes into contact with the upper surface of the magnetic disk so as to be pressed, and the lower magnetic head 9 'comes into contact with the lower surface, which is the surface of the magnetic disk opposite to the upper magnetic head 9, so as to be pressed.
The magnetic disks are composed of an upper magnetic head 9 and a lower magnetic head 9 '.
Thus, the upper and lower surfaces are sandwiched. This sandwiching state is formed under a head loading state described later.

Cassette storage body 3 housing cassette 4
Presses the eject button 20 to move the eject plate 2 toward the rear of the chassis 1.
The guide roller is pushed by the lower slope of the inclined groove 13 provided in the above, and the cassette housing 3 is pushed up. Further, the guide roller moves upward in the vertical guide groove 14 provided on the side surface side of the chassis 1 and moves to a direction away from the chassis 1 surface as shown in FIG. 4 is discharged from the cassette housing 3. This state is maintained by the protrusion 10 at the rear of the eject plate 2 being engaged with the claw 7 of the release plate 5.

When the cassette housing 3 moves away from the surface of the chassis 1, the upper head arm 8 is pivoted upward against the head spring 8a by a seat 17 provided at the rear of the cassette housing 3, As shown in FIG. 1, the upper magnetic head 9 is kept away from the magnetic disk stored in the cassette 4.

The cassette 4 is moved toward the rear of the chassis 1 so that the rear end 18 of the cassette 4 contacts the contact portion 5 of the release plate 5.
Is pressed and the release plate 5 is rotated, so that the claw 7 and the eject plate 2
Of the ejection plate 2 is released.
Is moved toward the front of the chassis 1 by the return spring 16. When the eject plate 2 moves forward of the chassis 1, the guide roller provided on the side surface of the cassette housing 3 is pushed by the upper slope of the inclined groove 13, and the cassette housing is pushed down. The guide roller moves downward in the vertical guide groove 14, and as shown in FIG. 2, the cassette housing 3 moves toward the chassis 1 surface, and the upper head arm 8 rotates so that the cassette can rotate. 4 is in a state where the upper magnetic head 9 is in contact with the magnetic disk, that is, a head load state.

In the head loaded state, as described above, the upper magnetic head 9 and the lower magnetic head 9 'are in a clamping state in which the magnetic disk is clamped from both upper and lower surfaces. A description will be given of an operation state leading to the sandwiching state.

As the eject plate 2 is moved forward of the chassis 1 by the return spring 16, the cassette housing 3 descends toward the chassis 1, so that the magnetic disk inserted into the cassette housing 3 is The lower surface is pressed against the lower magnetic head 9 'of the lower head member. As the cassette housing 3 descends, the seat 17 of the cassette housing 3 that has held down the downward rotation of the upper head arm 8 against the head spring 8a is lowered. The upper magnetic head 9 is pushed downward by the use spring 8a and lands so as to abut the upper surface of the magnetic disk.

As described above, the magnetic disk is sandwiched between the upper and lower magnetic heads 9 and 9 'which are in contact with each other so as to be hit from both upper and lower surfaces. The hard upper and lower magnetic heads 9 and 9 'which abut against each other so as to pinch them from both sides are designed to soften the abutment of the upper and lower magnetic heads 9 and 9' when sandwiching them so that the recorded information on the magnetic disk is not broken. To prevent the recorded information from being damaged.

In the case of a so-called single-sided magnetic head system in which the magnetic head is not used on one side of the magnetic disk, the magnetic head is not pinched so as to be hit from both sides by a hard magnetic head. Even if the end of the head is not softened, the recorded information will not be damaged. This damage of recorded information has occurred in a so-called double-sided magnetic head system in which a magnetic disk is sandwiched between both magnetic heads, and a measure for preventing magnetic disk recording information from being damaged by a magnetic head is a double-sided magnetic head system. This is a unique issue.

An eject button 20 is provided at the front center of the eject plate 2. As shown in FIGS. 3 and 4, a small rotary oil damper 11 is provided on the chassis 1 near the eject button 20. At the front of the eject plate 2, a projection 15 is provided integrally. Projection 15
Is provided with a square hole 19.

As shown in FIGS. 3 and 4, the pin 12 of the rotary oil damper 11 is fixed at a position eccentric from the center of rotation of the rotary oil damper 11, which is formed on the protrusion 15 of the eject plate 2. It is engaged with a square hole 19 which is an engagement hole.

When the cassette 4 is pushed in the rearward direction of the chassis 1 to release the engagement between the projection 10 of the eject plate 2 and the pawl 7 of the release plate 5, the eject plate 2 The spring 1 moves toward the front of the chassis 1. Since the pin 12 of the rotary oil damper 11 is engaged with the engaging hole 19 provided in the projecting portion 15 of the eject plate 2, the movement of the eject plate 2 is directly controlled by the rotary oil damper 11, The front movement of the eject plate 2 becomes slow.

Therefore, the vertical guide groove 1 is formed by the inclined groove 13.
4, the guide roller gradually descends, and the cassette housing 3
Then, the upper head arm 8 provided with the upper magnetic head 9 is slowly moved toward the chassis 1 surface, and a head loading state is established.

Accordingly, the upper magnetic head 9 of the upper head arm 8 can be softly landed on the magnetic disk by gently dropping the cassette housing 3 and the upper head arm 8, and damage to the magnetic recording portion of the magnetic disk can be prevented. It is done.

Further, since the pin 12 provided eccentrically from the rotation center of the rotary oil damper 11 is slidably engaged with the engagement hole 19 of the eject plate 2, the eject plate 2 is moved in the forward direction. The arm length of the moment for the force acting on the pin 12 from the eject plate 2 formed between the engagement point of the pin 12 and the engagement hole 19 and the center of rotation of the rotary oil damper 11 as the pin 12 moves. It will change along. This will be described.

That is, FIG. 3 shows a head unloaded state, and FIG. 4 shows a head loaded state.

As is apparent from FIG. 4, the pin 12 (shown by a dashed line) in the head unloaded state moves to the position shown by the solid line in the head loaded state. As can be seen from the movement direction of the eject plate 2 and the position of the pin 12 indicated by the arrow P, the length of the arm of the moment is short in the head unloaded state and long in the head loaded state.
As described above, since the length of the arm of the moment changes, the movement of the eject plate 2 tends to be heavier in the head unload state and lighter in the head load state.

On the other hand, the force by which the return spring 16 pushes the eject plate 2 toward the front becomes large in the head unloaded state and becomes smaller toward the head loaded state. This return spring 16
And the change of the arm length of the moment such that the movement of the eject plate 2 becomes lighter, the moving operation speed of the eject plate 2 is lower than that of the upper head arm 8. The change is small until the upper magnetic head 9 lands on the magnetic disk.
, A stable landing operation can be obtained.

The engagement hole 19 with which the pin 12 engages is formed in a square shape. The engaging hole 19 is provided in the original pin 12.
May be long enough to fit, but for the following reasons it is rectangular.

The ejecting plate 2 is configured such that an engaging projection 10 provided on the rear end side is engaged with and disengaged from a claw 7 of a release plate 5 rotatably provided on the chassis 1 and has a front end. The side is configured to engage with the pin 12 of the rotary oil damper 11 by engaging with the engagement hole 19. Parts have variations in dimensional accuracy. Due to the accumulation error of this variation, when the eject plate 2 is operated, the protrusion 10
There is a possibility that poor engagement and disengagement with the pawl 7 may not be performed, and malfunction may occur.

In order to cope with this malfunction, the engaging hole 19 is made square. That is, by making it square,
The pin 12 can play inside the engagement hole 19. That is, since the eject plate 2 and the rotary oil damper 11 are connected with play, even if there is some accumulation error described above, the accumulation error is absorbed by this play, and the malfunction is eliminated. .

Further, since the rotary oil damper 11 is not engaged with the upper head arm 8 but is engaged with the eject plate 2, the braking accuracy of the oil damper varies, and even if the accuracy is low, the upper head arm 8 is not affected. It does not hinder the operation of.

That is, the upper head arm 8 is provided with a pressing spring so as to press the upper magnetic head 9 against the magnetic disk. On the other hand, the eject plate 2 is also provided with a return spring 16. The return spring 16 of the eject plate 2 has a large spring force, while the pressing spring of the upper head arm 8 has a considerably small spring force.

The oil damper usually has a large variation in braking accuracy and a low braking accuracy. This is due to the fact that the viscosity of the oil tends to change with temperature. When the oil damper is engaged with the head arm 8, the variation in braking of the oil damper with respect to the small spring force of the pressing spring has a great effect, and the landing operation of the upper magnetic head 9 on the magnetic disk is too strong or too weak. The landing operation becomes unstable. However, in the case where the rotary oil damper 11 is engaged with the eject plate 2, since the pressing spring 16 of the eject plate 2 has a large spring force, there is not much influence due to the variation in braking of the oil damper.
The eject plate 2 performs a gentle and stable return operation with braking. For this reason, when the rotary oil damper 11 is engaged with the eject plate 2, the braking accuracy of the oil damper is low, and the landing operation of the upper magnetic head 9 on the magnetic disk is stable. .

In this embodiment, the eject button 20 is provided at the front of the eject plate 2 so as to protrude, so that the rotary oil damper 11 is provided in the space formed beside the eject button 20 as shown in FIGS. With this arrangement, even if the rotary oil damper 11 is provided in the magnetic disk drive, it is possible to provide a compact magnetic disk drive without increasing the external dimensions of the magnetic disk drive.

[0035]

As described above, the present invention relates to a chassis, an eject plate slidably mounted on the chassis so as to move back and forth along the surface of the chassis, and an eject plate. A cassette housing slidably mounted on the chassis so as to slide toward and away from the surface of the chassis by sliding in a direction perpendicular to the direction in which the plate slides, and the cassette housing along the sliding direction of the eject plate. A flat cassette, which is inserted into and removed from the cassette housing and which has a built-in magnetic disk, is connected to guide members provided on both sides of the cassette housing, and the guide members are slidably guided. And the movement of the eject plate moving toward and away from the surface of the chassis due to the sliding of the eject plate. An inclined groove for connecting a guide member provided on both sides of the eject plate to be added to the storage body, and the eject plate pushed into the back side is held in a pushed state and is pushed in with a cassette inserted into the cassette storage body. A lock mechanism for releasing the held state, and a return biasing means provided on the eject plate and returning the eject plate, which has been pushed in, to the front side by being released by releasing the lock mechanism. And a magnetic head means provided at a deep position of the chassis passing through the center of the chassis, the magnetic head means is disposed below the cassette, and a lower head member having a lower head, An upper head member which is disposed above the cassette and has an upper head and is rotatably supported; and A head spring provided to apply a force for pressing the head to the upper head member, and the cassette housing body is moved closer to the surface of the chassis by retreating the eject plate toward the front side. Thus, the lower surface of the magnetic disk contacts the lower head of the lower head member, and the upper head of the upper head member contacts the upper surface of the magnetic disk opposite to the lower head in contact with the upper spring. The magnetic disk drive is characterized in that the magnetic disk is held between the upper and lower heads in this manner, and a rotary oil damper is provided for braking the sliding movement of the eject plate.

According to this configuration, there are the following advantages.

(1). The eject plate is provided with a rotary oil damper that brakes the slide movement, so that when the cassette is inserted into the cassette housing, the eject plate moves backward by the return biasing means. Slow down due to oil damper braking.
For this reason, the clamping operation in which the upper and lower heads clamp the magnetic disk becomes gentle, so that the magnetic recording portion of the magnetic disk is not damaged.

(2). Since the rotary oil damper does not malfunction due to dust clogging the small air passage holes such as the cylinder type air damper, it does not hinder the attachment / detachment of the cassette to / from the cassette housing.

(3). The rotary oil damper has a simpler oil seal and a smaller size than the cylinder type oil damper, and thus contributes to the downsizing of the magnetic disk drive.

(4). Instead of providing the rotary oil damper for braking on the upper head member with the head spring, the rotary oil damper is provided on the eject plate that receives a strong return force by the return biasing means, so the braking accuracy of the rotary oil damper is Is slightly lower, the clamping operation of the upper and lower heads for clamping the magnetic disk becomes stable.

(5). The cassette housing and the eject board are
The guide member of the cassette housing is slidably connected to the guide plate of the eject plate by an inclined groove for connecting the guide member. Then, when pushing the eject plate to the back side against the return biasing means provided on the eject plate, the guide member is pushed by the lower slope of the inclined groove, and the cassette storage body is separated from the surface of the chassis. Slide to. When the lock mechanism of the eject plate is released from the cassette inserted into the cassette storage unit and the eject plate is returned to the front side by the return biasing means, the guide member is pushed by the upper slope of the inclined groove and the cassette storage unit is pressed. Slides closer to the surface of the chassis.

As described above, the sliding movement of the cassette housing body approaching or leaving the surface of the chassis is moved by being pushed by the ejecting plate on which the rotary oil damper against the return biasing means is being braked. It is always linked operation. For this reason, the cassette storage body does not move independently without interlocking with the sliding operation of the eject plate, and the slow clamping operation of the upper and lower heads for clamping the magnetic disk can always be reliably obtained.

[Brief description of the drawings]

FIG. 1 is a side view of a main part in a head unloaded state according to an embodiment of the present invention.

FIG. 2 is a side view of a main part in a head loaded state according to one embodiment of the present invention.

FIG. 3 is a top view at the time of head unloading according to one embodiment of the present invention.

FIG. 4 is a main part top view at the time of head loading according to one embodiment of the present invention.

[Explanation of symbols]

DESCRIPTION OF SYMBOLS 1 ... Chassis, 2 ... Eject plate, 3 ... Cassette housing, 4 ... Cassette, 8 ... Upper head arm, 8 '... Lower head arm, 9 ... Upper magnetic head, 9' ... Lower magnetic head, 11 ... Rotary type Oil damper, 13: inclined groove.

 ──────────────────────────────────────────────────続 き Continuation of the front page (72) Inventor Tetsuro Akasaki 1-1-1, Higashitaga-cho, Hitachi City, Ibaraki Prefecture Inside the Taga Factory, Hitachi, Ltd. (56) References JP-A-59-65977 (JP, A)

Claims (1)

(57) [Claims] 1. A chassis, an eject plate slidably mounted on a chassis so as to move back and forth along a surface of the chassis, and a slide perpendicular to a slide direction of the eject plate. A cassette storage body slidably mounted on the chassis so as to approach or move away from the surface of the chassis; and a cassette storage body that is slidably inserted into and removed from the cassette storage body along the sliding direction of the eject plate. And a flat-plate cassette with a built-in magnetic disk; guide members provided on both sides of the cassette housing; and a guide member slidably connected to the guide members, and an eject plate that slides back and forth. The cartridge housing is moved in a direction to move it toward and away from the surface of the chassis. And an inclined groove for connecting the guide members provided on both sides of the eject plate, the eject plate pushed into the back side is held in a pushed state, and the pushed state is held by the cassette inserted into the cassette housing. A lock mechanism to be released, a return biasing means provided on the eject plate and returning the eject plate, which has been pushed in, by being released by the release of the lock mechanism so as to retreat toward the front side; and a center of the chassis. Magnetic head means provided at a position on the back side of the chassis passing therethrough, the magnetic head means being arranged below the cassette, and a lower head member having a lower head, and being arranged above the cassette. An upper head member having an upper head and rotatably supported, and a force for pressing the upper head against the magnetic disk of the cassette. A lower head member provided with a head spring provided to be added to the head member, by moving the cassette housing body closer to the surface of the chassis by retreating the eject plate toward the near side; The lower surface of the magnetic disk comes into contact with the lower head, and the upper surface of the upper head member is pressed by the spring for the head to abut on the upper surface of the magnetic disk opposite to the lower head. A magnetic disk drive device comprising a rotary oil damper that is clamped by a head and that brakes the sliding movement of the eject plate.