JPS59160864A - Magnetic disk device - Google Patents

Abstract

PURPOSE:To detect accurate the index position of a magnetic disk and to reduce an electric power consumption by detecting the index position of the magnetic disk by a driving pin which engages an engagement groove, a permanent magnet which rotates together with an output shaft in one body, and a magnetoelectric transducing element fixed on a frame near the rotation locus of the permanent magnet. CONSTITUTION:The permanent magnet 21 for index position detection which rotates together with the output shaft 12 in one body is fixed to part of the outer circumference of a cover 20 which covers the lower end surface and outer circumferential surface of a rotor 17. Further, a Hall element 22 as the magnetoelectric transducing element which outputs an index detection signal on the basis of a magnetic field produced by the approach of the permanent magnet 21 that moves over rotation is fitted onto a substrate 18 corresponding to a part 5b to be driven. Then, the driving pin 15 abuts on the part 5b to be driven after rotating along the engagement groove 5c and transmits the driving force of rotation of a driving motor 13 to a hub part 5 to rotate the magnetic sheet 6. The part 5b to be driven corresponds to the index position of the magnetic disk 4, and when the permanent magnet 21 approaches the Hall element 22, the detection signal is outputted to detect the index position of the magnetic disk 4.

Description

[Detailed description of the invention]

Technical Field This invention relates to a magnetic disk device. Prior Art Conventionally, in a magnetic disk device for storing data input from an external device on an internal disk, an index hole 1a formed at the innermost circumference of a magnetic disk 1 is used as shown in FIG. Corresponding to this, a light-emitting element 2 that always emits light when the magnetic disk 1 rotates and a light-receiving element 3 that outputs an electric signal based on the light emitted to the magnetic disk 1 are arranged facing each other, and from the light-emitting element 2 11, r-, Detects the index position indicating the beginning of the track on the magnetic disk 1 every rotation based on the electrical signal output from the light receiving element 3 when the emitted light passes through the inch-inch hole 1a. In order to cause the light emitting element 2 to emit light, it is necessary to maintain its energized state.
A large amount of power is required, especially in battery-powered magnetic disk drives, which shortens battery life and reduces power consumption.
This has had the problem of easily causing malfunction of the JA device due to a drop in FA voltage. OBJECTS OF THE INVENTION In view of the above-mentioned drawbacks of the conventional art, an object of the present invention is to stop the index position (+'&
It is an object of the present invention to provide a magnetic tisf device which can detect the magnetic field r) and reduce the power consumption of the device. EXAMPLE Hereinafter, the present invention will be explained by referring to an example. FIG. 2 is a diagonal +b diagram 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. FIG. 6 is a partial cross-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, FIG. 8 is a cross-sectional view showing the head holding mechanism, and FIG. FIG. 10 is an explanatory view showing how the excitation coil of the drive motor is installed, and FIG. 10 is an explanatory view showing how the electric conversion element corresponding to the rotor of the drive motor is installed. In the figure, the magnetic disk 4 has an output shaft 12 (to be described later) in the center.
ff The hub part 5 has a chucking hole 5a for mating and has an engaging groove 5c around which a driven part 5b is formed, and one or both sides of the hub part 5 corresponds to the driven part 5b. A disc-shaped magnetic sheet 6, which has an index position indicating the head of one rack and stores the take, is fixed thereto. The magnetic disk 4 is placed in a cassette case 7 in which a hole 7a is formed at a location not corresponding to the hub portion 5, and an elongated head access hole 7b is formed at a location corresponding to the track surface of the magnetic sheet 6. Rotate it
It is stored in the f function. The inner boss of the hole 7a in the cassette case 7 is connected to the actuating body 8 which is always biased by the elastic force of a helical spring (none of which is shown) when the magnetic disk 4 is not attached. A shutter 9 for closing the head access hole 7b (n11) is rotatably mounted. Is this shutter 9 i? When the iJ recording magnetic disk 4 is attached to a magnetic disk device described later, a cut-out piece 44 formed on a cassette holder 38 described later
The actuator 8 is rotated by the actuator 8, which moves against the elastic force of the helical spring, thereby opening the head access hole 7b. In addition, a cassette holder 38 is provided on the front end surface of the cassette case 7.
An actuating piece 10 that turns on a write-protection detector 51 fixedly attached is mounted so that its position can be changed. The frame 11 in the m disk device has an output l1l.
The lI+lII line of Ih12 is shown in FIG. 4. The drive motor 13, which has a downward direction, is fixed. The output
1l112 is rotatably supported on the frame 11 via a bearing 14, and the engagement 7 shown in 11j1 is located at the second part shown in the figure.
^ 5 c and driven i; (i 5 b The drive pin 15 that transmits the rotational drive horn of the output III 112 to the hub part 5 by contact with the hub part 5 is planted, 1) 11. Heart part 5
The spindle huff 16 that supports the is fixed. Further, a disk-shaped rotor 17 is fixed to the 14-point end of the output i11::+12 in which permanent magnets having different magnetic poles are equally divided and arranged in a sequential manner. And 111 on the 1fiJ frame 11 (=111 on the J-cut board 13)
An excitation coil 19 having the same number of magnetic poles as the magnetic poles of the rotor 17.
is fixed opposite to the rotor 17, and its excitation! Gig
Rotate the output 1hb 12 by movement. 1) The rotor 17 (No. 11) has several covers 20 covering its lower end surface and outer circumferential surface, and a part of the outer circumference of the cover 20 has an index position detecting plate that rotates integrally with the output shaft 12 (Ilu). Permanent stone 21 is fixed. Also, in the vicinity of the rotational trajectory if!i of the permanent magnet 21, a permanent magnet 21 is generated due to the proximity of the rotating permanent magnet 21 on the substrate 18 corresponding to the opened driven part 5b described in iXI. A Hall element 22 as a magneto-electric transducer that outputs an index detection signal (not shown) based on a magnetic field is attached to the frame 11.
A step motor 24 having a rotating shaft 23 in a direction perpendicular to the line is fixed. The rotating shaft 23 is rotatably supported by a motor housing 25, and a rotor 26 having a large number of pole teeth is fixed to the periphery of the motor housing 25. An excitation coil 27 is fixed inside the motor housing 25 along the outer periphery of the rotor 26, and the rotor 26 and the motor housing 25
A compression spring 28 is interposed between the rotor 26 and the rotor 26 to the left (drive side) in FIG. J:; on the outer surface of the bearing 25a that constitutes a part of the motor housing 25;
An adjustment zinc 29 that adjusts JW is mounted so that its position can be changed by a screw 3o, and is configured to appropriately adjust the rotating shaft 23 in the direction of the l1Illl line. ii′+j The output ωj of the rotary shaft 23 has a single I-different part 3.
A feed screw 31 having a spiral 1a is fixed thereto, and a follower 32 is attached to the feed screw 31 along its base 31a. The follower 32 is -j,
The ii portion is smaller than the root diameter of the feed screw 31 (n11) (in a gear shape, it is wound at least half a turn, tJ, f or approximately one turn as shown in FIG. 7, and the other end is the feed screw 31). The follower 3 is made of an elastically deformable spring wire bent in a direction perpendicular to the axis of the feed screw 31 at a position tangentially away from the center of the screw 31 by an appropriate width α.
The other end of 2 is fixed to the frame 11 and supported flat with the feed line of the feed drive 31, and the tip thereof has a mark tU written on the track of the magnetic disk 4 at the position 1' corresponding to the output shaft 12. A magnetic head cartridge 34 has a hard-wired magnetic head cartridge 34 which includes a read/write head that reads data input from an external device and writes data input from an external device, and a fire extinguishing head that erases data written on the track surface. , 1Ilj
When the feed screw 31 rotates forward or reverse, the magnetic head cartridge 34 is reciprocated in a direction perpendicular to the '1ill line of the l axis 12. In addition, when the magnetic head cartridge 34 is moved to the i-immersion outer peripheral side of the magnetic disk 4, the magnetic head cartridge 34 comes into contact with the magnetic head cartridge 34, causing the track to be tracked.

Track detector 3 that detects [00]
5 is installed. Furthermore, 1) Note n! 5 [The stepping motor 13 and the step motor 24 are powered by electric oil 37 (FIG. 4) housed in the space formed in the device frame 36! (provided,
It is rotationally driven based on a drive command signal (none of which is shown) input from an external device. The cassette holder 38 is made of an elastic plate material such as a stainless steel plate, and has a side portion for inserting and holding the magnetic disk 4.
Guide portions 39a and 39b, which support and guide both W1j portions of the cassette case 7 when the cassette case 7 is in the high position, are bent and have a substantially U-shaped cross section. One guide portion 39a is pressed against the hub portion 5 of the inserted magnetic disk 4,
A collet 40 that maintains the engagement between the engagement groove 50 and the drive pin 15 is integrally molded. In addition, the guide portion 39a
A coil spring 42 whose one end is movably supported along the elongated hole 41 is attached to the coil spring 4 .
2 is compressed by F when the magnetic disk 4 is inserted, and when the magnetic disk 4 is ejected, the spring force of the coil link 42 causes the magnetic disk 4 to be ejected from the ejection amount -04,3 formed on the device frame j\36. Guide f on both sides
l! The free ends m of +39a and 39b are formed with raised pieces 44 that rotate the shutter 9 and open the head access hole 7b when the magnetic disk 4 comes into contact with the actuator 8 when inserted. The l+iJ cassette cassette holder 38 is integrally molded with an arm portion 45 of a part 4 which is bent so that the free end side of the cassette holder 38 is always positioned at the release position corresponding to the take-out opening 43. A fixing part 46 having a screw hole (not shown) is formed at the rear end of the arm part 45 and is fixed to the device frame 36. On the other hand, at the free end of the cassette halter 38, as shown in FIG. 5, when the cassette halter 38 is swung to &' A pair of locking portions 48 that engage with the convex hooking portion 47 are integrally bent. Further, as shown in FIG. 4, on the central plane part of the cassette holter 38, an output qim i 2 is provided to the chucking hole 5a in the magnetic disk 4 supported by the cassette holter 38, and a drive pin ~15 is provided to the engaging hole ζζ5C. Further, openings 49 are formed to operatively connect the magnetic head cartridges 34 to the track surfaces of the magnetic 1 sheet 6 through the head access holes 7b, and a new song opening 49 is formed to abut and support the tip of the inserted cassette case 7. The supporting plate 50 is integrally formed. Furthermore, on the central plane of the cassette holder 38, there is a write inhibit detector 51 which is turned ON by contact with the operating piece 10 attached to the cassette case 7 and outputs a write inhibit command signal. A cassette detector 52 is fixed to each of the cassette detectors 52, which is turned on by contact with the front rt'ii surface and detects that the popular disc 4 has been inserted. A head pressing member 53 for pressing the magnetic head cartridge 34 via the magnetic sheet 6 is attached to the support plate 50 in a support hole 50a formed at a position corresponding to the center of the output shaft 12 at Ajc. The head holding member 53 has a base portion 53a that is rotatably inserted into the N1 support hole 50a, and an arm to which a hat 54 for pressing the magnetic head cartridge 34 through the air seat is fixed on the distal end side. part 53b, and the stopper f1 ((as a material, the motor housing 25
The other arm portion 53C that presses against the outer surface of the cassette case 7 and the engaging portion 53d that engages with the tip of the cassette case 7 when the magnetic disk 4 is inserted are integrally formed of an elastically deformable spring member. The head holding member 53 is engaged when the magnetic disk 4 is inserted into the cassette holder 38.
When pressed, the pad 54 is brought into pressure contact with the surface of the magnetic sheet 6 due to the bending of the arm portion 53b, thereby pressing the magnetic head cartridge 34. In FIG. 4, 55 is a power switch, 56 is a connector part connected to an external device, and 57 is a base end fixed to the device frame 36, and a free 1.1μ part and an upper plane of the kite member 39a. It has an L-shape that presses against the cassette holder 38 and is made of an elastically deformable spring material. 11 Nu Departure I” 43
This is a closing member that blocks a part of the magnetic disk 4 and prevents other magnetic disks 4 from being inserted into the magnetic disk device. Next, the operation of this embodiment will be explained with reference to FIG. 11, which shows the mounted state of the magnetic disk. To install the magnetic disk 4 in the magnetic disk device,
When the magnetic disk 4 is inserted into the cassette holder 38, which is located at the release position shown in FIG. 4 due to the elasticity of the arm portion 45, from the removal amount 43, both sides of the cassette case 7 are supported and guided by the guide portions 39a and 39b. Ru. When the operating body 8 comes into contact with the cut and raised piece 44 as the magnetic disk 4 is inserted, the head access hole 7b is opened by the rotation of the shutter 9, and the actuating body 8 comes into contact with the front end surface of the cassette case 7. coil spring 42
to be compressed. Also, when inserting the magnetic disk 4, the tip of the cassette case 7 is inserted into the engaging portion 5.
3d, the head holding member 53 engages with the retaining portion 53.
As shown in FIG. 11, move the intake part 53b downward 1 L according to the press JH of d, and open the head access hole 7b.
The pad 54 is brought into pressure contact with the magnetic sheet 6 via. Also, the write-protection detector 51 is turned on according to the movement state of the actuating piece 1o attached to the cassette case 7, and outputs a write-protection detection signal. , and outputs a cassette detection signal indicating that the magnetic disk 4 has been inserted to the external device δ. In the above state, when the cassette holter 38 is swung to the JA landing position shown in FIG. 11 against the elastic force of the arm portion 45, the locking portion 48 is engaged with the locking stop Δ(; ,
The attached state is maintained. Also Chuckink Hall 5a
Output to! +l+ 12 is engaged, and the engagement groove 50
The drive pin 15 is engaged with. The track surface of the magnetic sheet 6 is brought into contact with the magnetic head cart cartridge 34 through the open head access hole 7b, and
The magnetic head cartridge 34 is pressed against the pad 54.
and the track surface are maintained in contact with each other. By this operation, the magnetic disk 4 is operatively connected to the drive motor 13, as well as the magnetic head cartridge 34, respectively. Note that when the cassette holder 38 is swung to the mounting position shown in FIG. The magnetic disk 4 is located in a portion of the magnetic disk drive to prevent incorrect insertion of the magnetic disk 4 into the magnetic disk device. In order to detect the index position of the magnetic disk 4 mounted in the magnetic disk device by the above operation, when the drive motor 13 is rotationally driven based on a drive command signal from an external device, the drive motor 13 is rotated integrally with the output shaft 12. After the driving pin 15 rotates in the engagement groove 5c by 7 steps, the driven part 5
b, and transfers the rotational driving force of the drive motor 13 to the hub portion 5.
The air is transmitted to rotate the intake sheet 6. The driven portion 5b corresponds to the index position of the disk 4, and the water container 21 that rotates integrally with the output shaft 12 is arranged corresponding to the driven portion 5b of 1111. When the Hall element 22 is brought close to the Hall element 22, the Hall element 22
outputs an index detection signal based on the magnetic field 21 that can enter the water, and detects the index position on the magnetic disk 4. Next, when the step motor 24 is driven based on a write command signal, a poetry command signal, or an erase command signal (none of which are shown) input from an external device, the feed screw 3
1 is rotated integrally with the rotating shaft 23, and a follower 3 that moves in the axial direction according to the rotation of the feed screw 31.
2, the magnetic head cartridge 34 is moved. The follower 32 is wound in a shape with one end slightly smaller than the root diameter of the feed screw 31, and is bent in a half-f direction with respect to the feed screw 31, and is cured into a high portion 31a to become elastic. Since it is installed in a deformed twisted state and is pressed in the ll1lll direction, the magnetic head cartridge 34 can be reliably moved in the axial direction without causing backlash when changing the direction of rotational force from L7J to normal rotation of the feed screw 31 and reverse rotation. The other end of the follower 32 is bent in the direction perpendicular to the #+ line at a position tangentially away from the center of the feed screw 31 by an appropriate width α. When stress is applied to the end, J and E for the feed screw 31
It is possible to disperse the force, prevent a decrease in the rotational torque of the feed screw 31, and move the magnetic head cartridge 34 in the axial direction with approximately uniform torque. When writing data input from an external device, reading data written on the magnetic disk 4, or erasing data written on the magnetic disk 4, the line 1III is inserted at the center position of the output shaft 12. When the magnetic head cartridge 34 is moved to the I'l outer circumferential side of the magnetic disk 4 and the track detector 35 is turned on,
The step motor 24 is stopped and the magnetic head cartridge 34 is positioned at track (00). After accessing, for example, file data, start position data, etc. written in the track (00), a predetermined operation is executed. The track (00
) To adjust the position of the magnetic head cartridge 34 in accordance with
When the fixing position is changed as appropriate, the rotating shaft 23 is moved in the li'+l+ line direction by or against the spring force of the compression spring 28, and the magnetic head cartridge 34 is moved. Then, when the head cartridge 34 comes into contact, a track detection signal is output from the track detector 35, and the rotation 123 and the adjustment link 2
9 is fixed, and the position of the magnetic head cartridge 34 is adjusted. To immediately eject the magnetic disk 4 from the magnetic disk device, push the locking portion 48 through the F section of the removal amount 43 shown in FIG. The cassette holder 38 is released and the elastic force of the arm portion 45 swings the cassette holder 38 back to the release position. This operation causes the protruding horn shaft 1 to move toward the chucking hole 5a.
2, or the engagement of the drive pin 15 with the engaging portion 50 is released, and the magnetic disk 4 is automatically moved out of the magnetic disk drive from the ejection opening 43 by the spring force of the coil spring 42. be discharged. Along with the ejection, the engaging portion 53d of the head holding member 53 and the cassette case 7
When the engagement with the tip end is released and the arm part 53b is returned to its original position, the pressure contact of the pad 54 against the magnetic sheet 6 is released. Further, when the contact between the cutting and raised piece 44 and the actuating body 8 is released as the magnetic disk 4 moves out, the actuating body 8 is returned to its original position by the elastic force of the spiral spring, and the shutter 9 is rotated. to close the head access hole 7b. Accordingly, in this embodiment, the index position on the magnetic disk 4 is detected by the index detection signal outputted from the Hall element 22 based on the magnetic field of the Kugenshi 21 at 7 which approaches the magnetic disk 4 as the magnetic disk 4 rotates. -! It is possible to develop Aiδ into a low-consumption type. In this embodiment, the permanent magnet 21 is fixed to a part of the outer periphery of the cover 20, but in the present invention, a concave part or a convex part is formed in a part of the outer periphery of the rotor in the drive motor, and the permanent magnet 21 is fixed to a part of the outer periphery of the cover 20. The nIJ recording part name can be implemented even if the index position on the magnetic disk is detected by an electric signal output from a magnetoelectric transducer based on a change in the magnetic field based on the convex part. DETAILED DESCRIPTION OF THE INVENTION As described above, the present invention includes a magnetic disk having a center hole in the center and an engagement groove formed around the center hole;
i. A motor having a protruding horn shaft that fits into the center hole of i1, and a drive pin that is fixed on the output shaft so as to rotate around the output line III and that can be engaged with the engagement part of mJ. , with a simple configuration that detects the index position of the magnetic disk using a permanent G stone that rotates integrally with the output shaft and a magnetoelectric conversion element fixed on the frame near the rotation locus of the permanent magnet. The present invention is a magnetic disk device that can accurately detect the index position of a magnetic disk, and can reduce the power consumption of the device.

[Brief explanation of the drawing]

FIG. 1 is an explanatory diagram showing a conventional example, FIG. 2 is a perspective view showing an outline of a magnetic disk device according to the present invention, FIG. 3 is a partially cutaway perspective view showing an outline of a magnetic disk, and FIG. Figure 5 is an explanatory diagram showing the structure of the magnetic disk drive, and Figure 6 is an explanatory diagram showing the structure of the magnetic disk device.
The figure is a partial sectional view showing the 444 structure of the step motor.
The figure is an explanatory diagram showing how the follower is attached to the feed screw, Figure 8 is a sectional view showing the head presser (16), Figure 9 is an explanatory diagram showing how the excitation coil of the drive motor is attached,
FIG. 0 is an explanatory diagram showing how the magnetoelectric conversion element corresponding to the rotor of the drive motor is attached, and FIG. 11 is an explanatory diagram showing how the magnetic disk is attached. In the figure, 4 is a magnetic disk, 5a is a chucking hole including the center hole, 5C is an engagement groove, and 12 is an out)J11!11
13 is a drive motor, 15 is a drive pin, 21 is a permanent magnet,
22 is a Hall element as a magnetoelectric conversion element. Patent applicant Brother Industries, Ltd. agent Patent attorney Ken Ito - Figure 1 Figure 2

Claims (1)

[Claims] 1. A magnetic disk having a center hole at the center 1) and an engaging crystal formed around the center hole, and an output shaft that can fit into the center hole described in No. 111. (a) a motor fixed to the output shaft of item 11 so as to rotate around the output shaft and engaging 111 of item 1111;
The index position 16 of the magnetic disk is detected by a drive pin that can be engaged with the output 6h, a permanent magnet that rotates integrally with the output 6h, and a magnetoelectric transducer that is identified on the frame near the rotation locus of the permanent magnet. A magnetic disk device with seven features.