JP2593537B2 - Disk unit - Google Patents

Description

Description: BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a disk device for rotating a disk as a recording medium to record or reproduce information on the disk.

[Prior Art] A representative example of this type of device is a floppy disk device (hereinafter abbreviated as FDD) for magnetically recording or reproducing information on a magnetic disk of a flexible disk-shaped magnetic recording medium called a floppy disk. There is. In FDD, a magnetic disk is inserted and mounted so that it can be ejected,
A magnetic disk is rotated by driving a motor, and a magnetic head is brought into sliding contact with the magnetic disk to perform recording and reproduction. In the FDD structure, a disk insertion and ejection mechanism for inserting and ejecting a magnetic disk, a disk rotation drive mechanism for driving the magnetic disk to rotate by a motor, and a magnetic head are mounted on a base that supports each component of the FDD. A head seek mechanism for moving to an arbitrary track position along the radial direction, and a head loading mechanism for loading and unloading the magnetic head onto and from the disk are provided. In addition, a main control circuit board provided with a control circuit for controlling the entire FDD, a motor control circuit board provided with a drive control circuit for a disk drive motor, and an interface connector and a power supply for a host device. A connector and the like are provided.

Such an FDD is used as an external storage device of a host electronic device such as a personal computer or a word processor, and is configured as an independent single device.
In many cases, it is incorporated into the main body of the host electronic device. In recent years, electronic devices incorporating FDDs have become smaller and more portable, and accordingly, there has been a strong demand for FDDs to be smaller, thinner, and lighter.

[Problems to be Solved by the Invention] By the way, in the conventional FDD, the base is often made of die-cast and has a complicated cross-sectional shape. FD
In order to reduce the size, thickness, weight, and cost of D, the base is made of a sheet metal mold, and its cross-sectional shape is made simple, for example, the cross-sectional shape along the width direction is changed to a substantially U-shape. It is possible to do.

However, when the base is formed as described above, the mechanical strength of the base becomes weak, and there is a possibility that the base may be distorted due to a stress applied particularly when the FDD is incorporated and mounted in the electronic device of the host. FDD when distortion occurs in the base
The positional relationship between the components described above is displaced, which hinders accurate and satisfactory recording and reproduction, and causes a problem in the reliability of the apparatus.

On the other hand, it is, of course, required to reduce the number of parts and to reduce the cost of the FDD as well as to make it smaller, thinner and lighter.

On the other hand, in the conventional FDD, there is room for reducing the number of parts, for example, using three or more screws to attach the main control circuit board to the base.

Therefore, an object of the present invention is to solve the above-described problems not only in the FDD but also in a disk device so that the device can be reduced in size, thickness, weight, and number of parts without reducing the reliability of the device. It is in.

Means for Solving the Problems In the present invention, in order to solve the above-mentioned problems, in a disk device for recording or reproducing information by rotating a disk as a recording medium, a control circuit is provided for a base of the disk device. The circuit board is held on the base by engaging the board and pressing an engagement portion of the circuit board with the base by a shield cover for noise shielding so that the engagement is not released. Employs a structure that serves as a reinforcing member for preventing distortion of the base.

[Operation] According to such a structure, by holding the control circuit board on the base by pressing the shield cover, a fixing member for the control circuit board such as a screw can be omitted. The base can be reinforced with a shield cover to prevent distortion of the base.

[Example] Hereinafter, an example of the present invention will be described in detail with reference to the drawings. In the present embodiment, a floppy disk drive device (hereinafter referred to as FDD), which is appropriately incorporated in an electronic device such as a computer or a word processor and records and reproduces information, will be described as an example.

The FDD of the present invention is formed as a small and thin housing as shown in the first series (A) to (D). In the figure, reference numeral 10
Reference numeral 0 denotes a base for supporting the components of the disk device, which has a U-shaped cross section with an open top, is made of metal or the like, and in this embodiment, the base is an FDD.
, And various components are all housed between the base and a shield cover as a lid described later.

FIG. 1 (C) shows the back surface of the FDD, and a bottom mounting portion 101 for mounting to a host device such as a computer or a word processor is formed as a through hole for screwing, for example, at three places on the rectangular back surface. ing. A cut-out portion 102 is formed at a position where a rectangular shape is provided to supplement the three bottom mounting portions, as a relief at the time of mounting. That is,
Conventionally, four attachment points are usually provided, and three attachment points are provided, and the remaining one is formed as an attachment escape part.

The base 100 is cut or cut into various shapes to attach each component of the disk device, and this will be described as needed.

A portion near the center of the base 100 is cut out in a round shape, and a stator yoke 111 made of a magnetic material such as an iron plate provided on a lower surface of a motor 110 of a disk drive motor to be described later is fitted and fixed flush with the base 100. .

In particular, as shown in FIGS. 3 (B) and 4 (A)-(D), the stator and the stator yoke 11 are flush with the base and the lower surface of the base.
PCB with DD motor drive control circuit (not shown) on top of 1
(Printed circuit board) 300 are arranged in an overlapping manner. In order to reduce the thickness of the FDD, a portion of the PCB facing the rotor 115 of the DD motor 110 is cut out as an opening 300a so that the DD motor can be seen. PC300 as evident from the figure
For example, six coils 112 for exciting the DD motor are arranged at equal angular intervals on the stator yoke 111 in the opening 300a which is cut out so as to face the rotor 115, and the wiring inside the coil is a FG PC.
Pattern 1 for coil terminal connection formed on the coil side of B
12a is connected by soldering, for example, and coil 1
The connection between 12 and the motor drive control circuit on the PCB 300 connects the coil terminals directly to the PCB 300. Separately use the coil terminal (coil terminal) of the coil 112 without using a lead wire.
By directly connecting to the motor drive control circuit on the CB300, cost reduction and space saving can be achieved. Further, two Hall elements 113 that detect the switching timing of the excitation of the coil by utilizing the space between the coils 112 are arranged. The terminal of the Hall element 113 is soldered to the PCB 300, and the detection unit protrudes from the PCB 300 so as to face the rotor magnet 115a and is arranged in the opening 300a.

The DD motor 110 has a stator yoke 111 integrally fixed to the base 100 at a lower portion, and a housing 111b for housing a bearing 111a is fixed to the stator yoke. The center of this bearing is the spindle shaft 11 of the DD motor.
4, and a rotor yoke 115 is fixed above the spindle shaft 114. A magnet 115a is fixed to the back side of the rotor yoke 115, and is arranged to face the coil 112 via an air gap. In addition, as schematically shown in FIG.
A pattern 112b for FG (frequency generator) is provided above the 112 to detect the number of rotations of the coil. The pattern for FG and the driving circuit board 300 are also connected by, for example, soldering. ing.

A front panel 120 having an insertion / ejection port for the disc cassette 150 is attached to the front side of the base 100 in the drawing,
Both sides 100a, 100a of the U-shaped profile of the base 100
Are connected on one side to form the front surface of the housing.

Further, as shown in FIGS. 5 (A) and 5 (B), a shutter 122 for closing the cassette insertion / ejection opening 121 so as to prevent foreign matter such as dust from entering when not in use is attached to the inside of the front panel 120. I have. This shutter is rotatably supported by a bearing portion 124 provided above the cassette insertion / ejection port 121, and further always closes the cassette insertion / ejection port via a weak coil spring 125 as a first elastic member. It is given the habit of turning downward. Therefore, when no external force is applied, the shutter always hangs downward to close the cassette insertion / ejection opening 121. Above the shutter 122, one end of a brake spring (leaf spring) 123 as a second elastic member is fixed inside the front panel 120. The brake spring 123 is formed by bending downward from a material having a relatively large elastic coefficient as shown in the figure. When the cassette is mounted and a cassette guide described later is pressed downward, the brake spring 123 is bent. The tip does not reach the shutter 122,
The shutter 122 contacts the shutter 122 only when the cassette is not inserted or ejected, and urges the shutter 122 in the closing direction. The elastic modulus of the brake spring is selected so that a spring stronger than the coil spring 125 is obtained.

Next, FIG. 6, FIG. 7 (A) to (C), FIG. 8 (A),
The disk loading / unloading and head loading mechanism will be described with reference to FIG.

In the FDD device of the present embodiment, it is assumed that chucking of the disk and loading of the magnetic head are performed by loading the disk cassette 150, and unloading of the magnetic head and ejection of the disk cassette are performed by operating the eject button.

In the drawing, a disk cassette (hereinafter, abbreviated as a cassette) 150 is loaded and discharged through a disk cassette loading / unloading port 121 formed in a front panel 120 attached to a front end portion (a front side in the drawing) of the base 100. .

An ejector indicated generally by reference numeral 160 is provided inside the base 100 having a U-shaped cross section. Also base 1
A slide plate 162 is disposed on the base 00 so as to be guided by a plurality of bent portions 100m projecting from predetermined positions of the base so as to slide on the base in the A and B directions. A notch 162a is formed in a part of the slide plate 162. The other end of the tension coil spring 162b, one end of which is fixed to the base 100, is attached to the slide plate 162 in a state where the whole faces the notch 162a. As described later, the slide plate 162 is held at a predetermined position on the base 100 through the aforementioned bent portion 100m provided on the base by pulling the tension coil spring 162b in the direction B, and the slide plate 162 Operation button (eject button) 16 integrally attached to the front end in the figure
By pushing in 1, it is possible to slide in the direction A with respect to the base 100 against the bias of the tension coil spring 162 b.

As shown in FIGS. 8A and 8B, a guide groove 162e is formed in a guide plate 162d provided vertically on both sides of the slide plate 162. This guide groove 162e
As is clear from the figure, the outer end portion is formed parallel to the base 100 and obliquely descends therefrom.

8 (A) and 8 (B) also show the cassette guide 152.
(See also FIG. 3 (A)). The cassette guide 152 accommodates and guides the cassette 150, and is formed in a thin housing shape that fits entirely in the base 100, and the lower surface is cut out over substantially the entire area so that the cross section becomes substantially U-shaped. ing.

Dowels 152a project outward from both sides of the cassette guide 152 so as to be engaged with guide grooves 162e formed in the guide plate 162d of the slide plate 162, respectively. Further, dowels 152b project from central portions of both side surfaces of the cassette guide 152, and are fitted into guide grooves 100c formed on both side surfaces 100a of the base 100.

An ejector 160 is mounted near the rear end of the slide plate 162. That is, a shaft 160a for supporting the ejector 160 is protruded in the vicinity of the end opposite to the front panel 120 side of the base 100.The ejector spring 164 is elastically mounted on this shaft 160a, and the ejector 160 is moved around the shaft 160a. It is pivotally supported. One end of the ejector spring 164 is locked to the ejector 160, and the other end is accommodated in a spring receiving portion formed on the side surface 100a of the base 100, thereby giving the ejector a counterclockwise rotation behavior in the figure. ing. In particular, FIGS. 7 (A) and (B)
As is apparent from the figure, the ejector 160 has an arc-shaped base 160b.
The arm 160c is provided with a shutter opening and pushing arm 160d for the cassette. The arc-shaped base 160b is in contact with the base side surface 100a at the base side surface end surface to regulate the standby position of the ejector 160.

At the end of the slide plate 162 on the ejector 160 side, a protruding piece-shaped latch portion 162c is formed. As shown in FIG. 7 (A), the latch portion 162c is hooked on the base 160b of the ejector 160 at the standby position, thereby causing the tension coil spring 162b stretched between the base 100 and the slide plate 162 to move in the direction B. The slide plate 162 is maintained in the latched state against the urging of. When the ejector 160 is moved to the operating position by the cassette 150 as shown in FIG. 7B, the slide plate 162 is slid in the direction B by the tension of the tension coil spring 162b when the ejector 160 separates from the latch portion 162c. I do.

Next, the head seek mechanism will be described. As shown in FIGS. 9 and 10, a rear wall 100b is integrally formed on the side of the base 100 opposite to the front panel 120 so as to stand vertically from the bottom surface of the base 100. The screw shaft 131 directly connected to the output shaft of the stepping motor 130 is inserted into the hole formed in the rear wall 100b, and the motor 130 side end of the screw shaft 131 is supported by the slide bearing 135, and the base rear wall 100b Support plate cut and raised at a predetermined distance from
Screw shaft 13 on pivot bearing 100d provided at 100f
A stepping motor 130 for driving a recording / reproducing head assembly 200 described later is mounted with the front end of the motor 1 supported. As shown in FIG. 9, the screw shaft 131 of the stepping motor has a spiral screw groove 131a.
Are formed, and as described later, this screw groove 131a
Needle pin 2 protruding from head assembly 200
02 is engaged. Further, a washer 132 for preventing lubricating grease or foreign matter from entering the coaxial bearing 135 from other portions of the screw shaft 131 is attached to a portion of the screw shaft 131 very close to the slide bearing 135. .

As shown in FIGS. 10 and 11, the head assembly 200 is provided on a guide bar 133 provided between a rear wall 100b of the base 100 and a support plate 100e cut and raised from the base, and a part of the head carriage. It is provided on the base 100 so as to be able to reciprocate via a mounted slide bearing 134.

The head assembly 200 is provided with a head carriage 201a having a head arm 201.
The slide bearing 134 is mounted on one side of 1a, and a needle pin 202 is provided on the other side.
02 is engaged with the screw groove 131a of the screw shaft 131 of the stepping motor 130. With such a structure, the screw shaft 131 rotates by the driving of the stepping motor 130, the needle pin 202 is pressed via the screw groove 131a, and the head assembly 200 reciprocates. A magnetic head for surface 0 is fixed below the head carriage 201a, and a magnetic head for surface 1 is supported via a head arm 201 on the upper side. A head arm 201 having a one-sided head can move toward and away from the disk, and the one-sided head soft-lands on the disk via a damper mechanism or a solenoid mechanism described below to record or reproduce information on the disk. I do.

First, FIGS. 12, 13 (A), (B), (C) and FIG.
FIGS. 7A and 7B illustrate the damper mechanism 170. FIG.

Damper mechanism 170 consists of damper 171 and damper arm 172
And is attached to the base 100 via a damper attachment plate 173. The damper mounting plate 173 is bent with a key and is screwed to the lower surface of the base 100. A support shaft 174 protrudes from the base rear wall side of the damper mounting plate 173 in parallel with the base side wall.
A damper arm 172 is rotatably supported at 74. A coil spring 175 is wound around the support shaft 174,
One end of 175 is supported on the side wall side of the base of the damper mounting plate 173, and the other end is supported by the damper arm 172, so that the damper arm 172 always has a rotation behavior toward the bottom surface of the base 100. A bent portion 172a protruding from the damper arm 172 is fitted into a notch formed in the rotary piece 171a of the damper 171, whereby the damper arm 172 and the damper 171 are linked. Further, the damper arm 172 is provided with first and second pivots 176 and 177.
The second pivot 176 is attached downward from the center of the damper arm to the tip of an arm 176a projecting in the disk direction, and the second pivot 177 is attached from the damper arm 172 toward the base. The first pivot 176 transmits the upward movement of the cassette guide 152 to the damper arm 172, and the second pivot 177 contacts the bottom surface of the base 100 and serves as a stopper below the damper arm. . The positional relationship between the two pivots 176 and 177 is such that the first pivot 176 contacts the upper surface of the cassette guide 152 when no cassette is inserted into the disk device, and the second pivot 176 when the cassette is inserted and mounted. By contacting the bottom of base 100 with 177,
The first pivot 176 is set so as to float from the upper surface of the cassette guide 152 by the gap G. This gap G
Is provided so that when the cassette is inserted and the head abuts on the disk, the damper arm 172 is securely separated from the head arm 201 without lifting the external force and does not hinder the movement of the head arm. It is what is being done.

FIGS. 15 and 16 (A), (B) and (C) show a solenoid assembly, which is used as an alternative to the above-mentioned damper assembly. The choice of using a damper mechanism or a solenoid mechanism is determined by the system of the host device on which the FDD is mounted. In general, when a damper mechanism is used, the head is loaded on the disk with the cassette mounted, and the disk is rotated only during read / write. When the solenoid mechanism is used, the disk is constantly rotated when the power is turned on, and the head is loaded on the disk by excitation of the solenoid only during read / write.

The solenoid mechanism 180 includes a solenoid 181, a plunger 182 attracted by excitation of the solenoid, and a head load arm 183.
Is screwed to the base 100 via. A U-shaped support portion 184a is provided so as to protrude from the solenoid mounting plate 184, and a support shaft 184b is supported by the support portion 184a. A head load arm 183 is rotatably supported on the support shaft 184b, and a coil spring 184c is wound therearound.
One end of the coil spring 184c is locked to the U-shaped support portion 184a, and the other end is locked to the head load arm 183.
This gives the head load arm 183 a clockwise rotation behavior in the figure.

The side of the plunger 182 opposite the main body of the solenoid 181 projects in the direction of the head assembly through a through hole (not shown) formed in the solenoid mounting plate 184.
Due to the attachment of 9, the amount of protrusion of the plunger 182 from the main body of the solenoid 181 is regulated. Further, a plunger return spring 185 is elastically mounted between the E-ring 189 and the solenoid, and applies a biasing force toward the head assembly to the plunger. In addition, noise reduction rubbers 186 are attached to the solenoid mounting plate 184 side of the E-ring of the plunger 182 and the inside of the outer end of the plunger, respectively, so as to buffer the impact due to the movement of the plunger and reduce noise due to the impact. .

A first pivot 187a is provided at the tip of the head load arm 183, and when no disk cassette is inserted in the FDD, the pivot 187a comes into contact with the upper surface of the cassette guide 152 to allow head loading. The arm 183 is in the first position against the bias of the coil spring 184c.
6It has been pushed up to the position shown in FIG. At this time, the lifter 204 of the one-side head arm 201 of the head carriage is supported by the head load arm 183, and the one-side head arm 201 is supported at a non-use position shown in the figure.

Further, a second pivot 187b is provided at a portion of the head load arm 183 which comes into contact with the plunger 182. FD
When the disc cassette is inserted into D, the cassette guide is lowered by the above-described cassette mounting mechanism, and the first pivot 187a is released from the upper surface of the cassette guide, so that the head load arm 183 applies the urging force of the coil spring 184c. As a result, the second pivot 187b comes into contact with the outer end of the plunger,
The head load arm 183 is held at the position shown in FIG. 16 (B). When the second pivot 187b contacts the plunger, the first pivot 187a is at a position where it does not contact the cassette guide. Therefore, in this position, the head arm 201 is supported by the lifter 204 by the head load arm 183, so that the head 205 is supported at a standby position at a predetermined distance from the disk 10.

In this state, when the solenoid 181 is excited and the plunger 182 is attracted in the direction of the arrow in FIG. 16C, the head load arm 183 further rotates clockwise in the figure by the urging force of the coil spring 184c. Occupy the position shown in FIG. 16 (C). In this position, the head load arm 183
Is separated from the head arm 201, and the one-sided head 205 provided on the head arm 201 contacts the disk 10.

Next, a circuit board will be described. As shown in FIG. 2, a PCB 400 as a main control circuit board is mounted on the cassette guide 152 so as to cover the above-mentioned various components. Further, as already described at the beginning with reference to FIGS. 3 and 4, a PCB 300 for a DD motor is arranged on the upper surface of the base 100. That is, in the conventional FDD, the main PCB, which is often arranged alongside the PCB for the DD motor on the lower surface of the base, in the present embodiment, the various components are sandwiched on the base 100 for the DD motor in the base 100. It is arranged facing PCB300.

As shown in FIG. 2, two notches 100a 'for supporting the main PCB 400 are formed on one side wall 100a of the base 100, and a notch for supporting the same PCB 400 is formed on the other side wall.
100a 'is formed at one position, and further, a support portion 100a "for screwing the PCB 400 is formed by, for example, being cut and raised. The support portion 100a' is formed at a position corresponding to the cutout 100a 'of the base side wall of the PCB 400. A joint protrusion 400a is formed, and a through hole for screwing is formed at a position corresponding to the support portion 100a ″, for example. With this configuration, when incorporating the PCB400 into the FDD, the PCB40
The protrusion 400a for engagement of 0 is fitted into the notch 100a 'of the base side wall, and is screwed to the support portion 100a "of the base side wall through a through hole with a screw 405.
Only the location. Then, as shown in FIGS. 1A and 1B, a shield cover 500 for noise shielding is attached so as to cover the whole. This shield cover has a rectangular plate shape, and the protruding sides 502 formed on both sides are overlapped on the outside of the side wall 100a of the base 100, and the side wall 100a is opposed to the hole 502a of the protruding side 502.
The projection 100p formed on the front panel 120 is engaged with the front panel 120, and the projection 100p is attached to the base 100 so as to overlap the base 100. At that time the shield cover
At 500, each of the protrusions 400 a of the PCB 400 is pressed by the claw-shaped PCB pressing portions 501 formed at positions corresponding to the notches 100 a ′. Thus, the main control board, PCB4
00 is engaged in the side wall of the base 100 and the shield cover 500
The PCB 400 is held on the base by being held down with. Further, by mounting the shield cover and the base in this manner, the shield cover can function as a reinforcing member for preventing distortion of the base.

As described above, in this embodiment, the DD
The PCB 300 for the motor and the PCB 400 as the main control circuit board are arranged facing the base 100 on the same side. Further, at least one set of an emitting element and a light receiving element constituting a transmission type optical sensor are arranged on both circuit boards so as to face each other. That is, for example, as shown in FIG. 3 (B), a light emitting element or a light receiving element 401 constituting a sensor for detecting a write protection and a light emitting element or a light receiving element 401 constituting a sensor for detecting a cassette are provided on a circuit board 300 for a DD motor. An element 402 is provided. As shown in FIG. 2 (A), the main control circuit board 400 has a light receiving or light emitting element 401 'of the cassette detecting sensor at a position directly opposite to the cassette detecting sensor element 401 and the write protection sensor element 402. Also, a light receiving or light emitting element 402 'of the sensor for detecting the write protection is attached.

Further, as shown in FIGS. 2, 3, and 17,
A connector section 140 is attached to an end of the FDD device opposite to the front panel 120. The connector section 140 includes an I / O connector 141 connected to a main control circuit for an interface with a host device, and a power connector 142 for a power supply. In this embodiment, the two connectors 141 and 142 are separated from the main control circuit board 400 and are arranged in two stages in the thickness direction of the FDD. In this case, the I / O connector 141 attached to the PCB 141a is Although the power connector 142 arranged in the lower stage and attached to the PCB 142a is arranged in the upper stage, the upper and lower arrangements may be reversed. The PCBs 141a and 142a are connected via a flexible printed circuit board (cable) 143a, and the PCB 142a and the main control circuit board 400 are also connected via a flexible printed circuit board 143b. Although the I / O connector 141 includes a large number of ground terminals, since these ground terminals are collectively connected to one common lead wire pattern and pulled out, the cable of the flexible printed circuit board 143b is The number is reduced, and the space is also saved here.

When the disk drive (FDD) having the above configuration is mounted on an electronic device such as a computer or a word processor, as shown in FIG. 1 (C), the bottom mounting portions 101 formed at three places on the back surface of the base of the FDD are installed. For example, it is screwed to an electronic device. The FDD is fixed to the electronic device by three-point support because the fixing is performed at only three of the four places forming the rectangle and the remaining one is cut out as a relief. Therefore, even if there is a dimensional error in the FDD fixing portion on the electronic device side and there is a height difference, the base 100 can be prevented from being distorted without applying a stress to the base 100 to distort the base 100.

Next, the operation of the FDD of the present embodiment configured as described above will be described.

The electronic apparatus having the FDD mounted as described above is turned on, and then the disk cassette 150 is inserted into the cassette guide 152 of the FDD via the cassette insertion / ejection port 121 of the front panel 120 of the FDD.

At this time, the cassette 150 is braked via the shutter 122 biased by the coil spring 125 and the brake spring 123,
When inserting the cassette 150, there is no problem because the force for pushing the cassette 150 by hand is strong.

When the cassette 150 is inserted into the FDD, the cassette detection sensor elements 401 and 401 'and / or the cassette 1 disposed on the motor drive control board 300 and the main signal control board 400 are arranged.
50 write protect sensor elements 402, 402 'are activated,
A signal indicating whether the cassette 150 is inserted and / or whether write protection is set for the cassette is input to the host device.

When the cassette 150 is inserted in the direction A in FIG. 7, the notch 150a provided at the front end of the cassette 150
The shutter portion of the arm portion 160c of 60 abuts against the shutter opening and pushing arm 160d of the cassette, and the shutter opening and pushing arm 160d of this cassette is pushed upward in the figure against the bias of the ejector spring 164 and turned counterclockwise. Let it.
At this time, the shutter release and push-out arm 16 of the cassette
Since the shutter 150b of the cassette is pushed leftward in the figure by 0d, the shutter of the cassette is opened together with the insertion of the cassette, and the disc is exposed. Further, the cassette 150 reaches the position shown in FIG.
When the shutter opening and pushing arm 160d of the cassette reaches a position parallel to the front end of the cassette, the ejector 160
Of the slide plate 162
Get out of 62c. Then, the engagement between the slide plate 162 and the ejector 160 is released, and the slide plate 162 slides in the direction B in the drawing by the tension of the tension coil spring 162b.

Since the dowels 152a formed by projecting on both side surfaces of the cassette guide 152 accommodating the cassette 150 are engaged with the guide grooves 162e of the guide plates 162d on both sides of the slide plate 162, the slide plate 162 is When the cassette 100 is pulled in the direction B, it is likely to be pulled together.
The cassette guide 152 cannot be moved in the directions A and B in the figure because the cassette guide 152 is engaged with the guide grooves 100c formed on both side surfaces 100a, 100a. Further, the guide plate 162d of the slide plate 162
Since the guide groove 162e is formed as a long groove inclined downward as shown in FIGS. 8A and 8B and already described, the slide plate 162 is
When pulled by the elasticity of 62b, it is guided by the guide groove 162e and is forcibly moved downward and fixed to the cassette mounting position.

Here, the case where the FDD is provided with a damper mechanism as a buffer mechanism of the head assembly will be described first.

As described above, the damper 171 is provided with the damper arm 172.
Although the coil spring 175 wound around 174 always gives a downward rotation behavior, a first pivot 176 provided downward at the tip of the damper arm 172 is supported on the upper surface of the cassette guide 152. This limits the downward movement limit when no cassette is loaded. When the slide plate 162 moves due to the loading of the cassette, and the cassette guide 152 moves in the direction of the base 100, the damper arm 172 supported on the upper surface of the cassette guide 152 is moved downward by the bias of the coil spring 175. You. However, oil is sealed in the damper, and the damper arm 172 slowly descends due to the oil resistance. Then, the head arm 201 of the head assembly 200 in which the lifter 204 is supported by the damper arm 172 is supported by the damper arm 172 and slowly descends, and the one-side head 205 soft-lands on the disk 10 and the zero-side head 206 The disk 10 is sandwiched between the disk 10 and the one-sided head 205.

In this state, the disk 10 is rotated at the time of reading / writing.

As described above, the damper is provided with the second pivot 177, and when the damper arm 172 is lowered, the second pivot 177 comes into contact with the upper surface of the base 100, and the damper arm 172 is moved downward. Movement is regulated.
In this state, as shown in FIG.
A predetermined gap is formed between the lifter 204 and the damper arm 172.

Next, a case where a solenoid mechanism is provided as a buffer mechanism of the head assembly will be described.

When the latch portion 162c of the slide plate 162 is disengaged from the ejector 160 by the insertion of the cassette 150, the slide plate 162 is pulled toward the front panel by the elasticity of the tension coil spring 162b. As a result, the cassette guide 152 guided by the guide plate 162d of the slide plate 162 via the dowel 152a moves downward. As a result, a pivot 187 is provided on the upper surface of the cassette guide 152.
The head load arm 183 of the solenoid 181 whose downward movement has been restricted by the riding of a rotates by the urging force of the coil spring 184c in the clockwise direction in FIG. 16A. Then, the second pivot 187b of the solenoid 181 comes into contact with the outer end of the plunger, whereby the rotation of the head load arm 183 is restricted, and the head load arm 183 is held at the standby position shown in FIG. 16 (B). You. In this position, the first pivot 187a occupies a position separated from the upper surface of the cassette guide 152 by a predetermined distance. At the same time, the one-sided head 205 of the head arm 201 in which the lifter 204 is supported by the head load arm 183 is separated from the disk 10. Waiting a predetermined distance away. When using a solenoid, the disk is usually rotated immediately after the power of the host device on which the FDD is mounted is turned on.

Next, energization is performed to the solenoid 181 and FIG. 16 (C)
As shown in FIG. 7, the plunger 182 is attracted against the bias of the plunger return spring 185, and the head load arm 183 further rotates clockwise by the biasing force of the coil spring 184c. Then, the head arm 201 supported by the head load arm 183 releases the restriction of the head load arm 183, and the coil spring 203a acting on the head arm 201
And the single-sided head 205
Abut. In this state, desired read / write of information is performed.

When the power supply to the solenoid 181 is cut off, the plunger 182 is returned to the standby position shown in FIG. 16B by the bias of the plunger return spring 185, and the one-sided head 205 is separated from the disk 10.

As described above, the head assembly 200 is slidably guided by a guide bar 133 supported on the base 100 via a slide bearing 134 attached to a part of the head carriage 201a. Since the provided needle pin 202 is engaged with the screw groove 131a of the screw shaft 131 of the stepping motor 130, the needle pin 202 is moved by driving the stepping motor 130.

The magnetic head 205 by moving the head assembly 200,
The position control of 206 is performed in a known manner, and will not be described here.

After reading / writing information from / to the disk as described above, when ejecting the disk, press the eject button 161 provided on the front of the FDD,
62 slides in the direction A from the position shown in FIG. 7B against the bias of the tension coil spring 162b. As a result, the latch portion 162c formed at the end of the slide plate 162 opposite to the eject button 161 is separated from the rear portion of the arc-shaped base 160b of the ejector 160, and the ejector spring 16
By the bias of 4, the arm 160c of the ejector 160 is rotated counterclockwise, and moves to the discharge position shown in FIG. 7A. At this time, the cassette 150 is pushed out in the direction of the front panel 120 by pushing the cassette 150 that has kept the shutter 150b of the cassette 150 provided at the end of the arm portion 160c of the ejector 160 at the open position and rotating the shutter opening arm 160d counterclockwise. It is. At this time, the shutter 150b of the cassette 150, which gradually releases the restriction of the arm 160d with the pushing of the arm 160c of the ejector 160 and the rotation of the shutter opening arm 160d, is closed by a spring mechanism (not shown). The cassette 150 is discharged from the FDD with the shutter 150b closed.

At this time, the movement of the cassette 150 is reliably braked by a strong braking force via the shutter 122 biased by the brake spring 123 and the coil spring 125 inside the front panel 120 of the FDD, whereby the cassette pops out and falls off. It will not be damaged. When the cassette 150 is mounted, only the coil spring 125 acts on the shutter 122,
A large load is not applied to the cassette 150.

[Effects of the Invention] As is apparent from the above description, according to the present invention, in a disk device for recording or reproducing information by rotating a disk as a recording medium, a control circuit board is mounted on a base of the disk device. The circuit board is held on the base by pressing the engagement portion of the circuit board with the base with a shield cover for noise shielding so that the engagement is not released. By adopting a structure that serves as a reinforcing member for preventing distortion of the base, by holding the control circuit board on the base by pressing the shield cover, it is possible to omit fixing members for the control circuit board such as screws, for example. Cost can be reduced by reducing the number of points. In addition, the base can be reinforced with a shield cover to prevent distortion of the base, without reducing the reliability of the disk drive, miniaturizing the disc drive,
It is possible to adopt a base structure that can be made thinner and lighter.

[Brief description of the drawings]

1A and 1B illustrate the structure of an FDD according to an embodiment of the present invention, and FIGS. 1A, 1B, 1C, and 1D are plan views each showing the overall appearance of the FDD. FIG. 2 (A) is a plan view of the FDD shown in FIG. 1 with a shield cover removed, FIG. 2 (B) is a front view of the same state, FIG. 3 (A) is a plan view showing a state where a shield cover of the FDD and a main control circuit board are removed, FIG. 3 (B) is a plan view showing an assembled state of a DD motor, FIG. 3 (C) is a side view, Fig. 3 (D) is a front view, Fig. 4 (A)
FIG. 4B is a side sectional view showing an assembled state of the DD motor, FIG. 4B is a perspective view of a main part showing an arrangement of a coil and a hall element of the DD motor, FIG. 4C is a plan view of the DD motor, and FIG. FIG. 4 (D) is a sectional view of the DD motor taken along line IV-IV of FIG. 4 (C), FIGS. 5 (A) and (B) are explanatory views showing the action of the brake spring and the coil spring, and FIG. Is a plan view showing the assembled state of the slide plate and the ejector, FIG.
(B), (C) is an explanatory view showing the operation of the ejector, the eighth diagram
9A and 9B are explanatory views showing the operation of the cassette guide, FIG. 9 is an explanatory view showing an assembled state of the stepping motor, FIG. 10 is an explanatory view showing an assembled state of the head assembly, and FIG. Configuration diagram of head assembly, No.
12 to 14 illustrate the damper mechanism. FIG. 12 is an explanatory view showing a state where the damper mechanism is mounted. FIGS. 13 (A), (B) and (C) are states where the damper mechanism is mounted. FIGS. 14 (A) and (B) are explanatory diagrams showing the operation of the damper, FIGS. 15 and 16 show a solenoid mechanism, and FIG. 15 is a configuration diagram of the solenoid mechanism; FIGS. 16 (A), (B) and (C) are explanatory diagrams showing the operation of the solenoid, and FIGS. 17 (A) to (C) are explanatory diagrams showing the arrangement of the connectors. 100 ... Base, 100a ... Side 100a '... Notch, 100a "... Support 100b ... Rear wall, 101 ... Bottom mounting part 102 ... Notch, 110 ... DD motor 111 ... Stator Yoke 112 ... Coil, 113 ... Hall element 114 ... Spindle shaft 115 ... Rotor yoke 115a ... Magnet 120 ... Front panel 121 ... Cassette insertion / ejection port 122 ... Shutter 123 ... Brake spring 130 ... Stepping motor 131: Screw shaft, 132: Washer 133: Guide bar, 140: Connector part 141: I / O connector 141a: PCB 142: Power connector, 142a: PCB 143a, 143b: Flexible PCB 300 …… Motor PCB 400 …… Main PCB 401 …… Cassette detection sensor element 402 …… Write protection detection sensor element 500 …… Shield cover

Claims (1)

(57) [Claims] In a disk device for recording or reproducing information by rotating a disk as a recording medium, a control circuit board is engaged with a base of the disk device, and the circuit board is prevented from being disengaged. While the circuit board is held on the base by pressing the engagement portion with the base with a shield cover for noise shielding,
The disk device, wherein the shield cover serves as a reinforcing member for preventing distortion of the base.