JP2001319301A - Compact high-speed drum storage device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a portable drum storage device having a high access speed. SOLUTION: This storage device has a high access speed realized by using a compact cylindrical storage medium and a combined head including a number of heads. This storage device includes the storage medium and a controller.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION A high-speed drum storage device that can be accessed by electronic computers and various electronic devices, and is used as a portable type.

[0002]

2. Description of the Related Art Conventionally, a cylindrical storage medium or a disk-shaped storage medium which is larger than that of the present invention has been used. In the case of a cylindrical storage medium, the head is often of a fixed type, and in the case of a disk-shaped storage medium, there are many devices having one head per storage surface. In many portable devices, only the storage medium is replaced.

[0003]

Conventionally, a relatively large-diameter storage medium is used to secure a storage capacity. Therefore, even a high-speed apparatus requires an average access time of several milliseconds. An apparatus using a cylindrical storage medium (2) and having a fixed head does not have a seek time for the head, but if the track density is high, it is difficult to manufacture the head. In a disk-shaped device, the head is usually one head on the storage surface, and a strong magnet and a coil are used to seek the head from a long distance by moving the coil from a long distance, thereby greatly improving the current access speed. It is difficult and the structure is complicated. Although a large number of heads are made at once, they are not used as a composite head in which many heads are integrated. In addition, when a large number of heads are used in an integrated manner, the defective rate increases. Portable devices are relatively large and access speed is slow, giving priority to storage capacity, and there are a wide variety of devices corresponding to recording methods, capacities, and media sizes. In many cases, compatibility is low, such as inability to use from. The impact of carrying the storage medium often damages the mechanism that holds the storage medium, or the head jumps and damages the head and storage surface.

[0004]

Means for Solving the Problems A cylindrical or columnar storage medium (2) having a small diameter of 20 mm or less is adopted, and a head is equipped with a number of recording / reproducing mechanisms as a composite head (4). It is driven by a voice coil motor (6) mounted in the moving direction at both ends. The voice coil motor (6) may be placed on only one side of the composite head (4), and a bearing may be placed on another end. In the composite head (4), a plurality of heads are collectively manufactured on an IC substrate, and a circuit for switching the heads is mounted on the IC substrate. IC of compound head (4)
An amplification circuit, a control circuit, an arithmetic circuit, a memory element, and the like can be mounted on the substrate in addition to the switching circuit. In addition, wiring for facilitating connection between other components can be mounted on the composite head (4). The drivable length of the voice coil motor (6) is at least twice the head interval. A hollow shaft (5) is employed and a voice coil (8) is wound around the shaft (5). It is also possible to mount a plurality of storage media (2) in the apparatus, bundle the storage media (2) and the composite head (4) to be paired, and drive them by the same voice coil motor (6). A head mechanism and a control circuit are mounted on the apparatus in addition to the storage medium (2), and the apparatus to be used can be used only with a power supply and an interface mechanism at a minimum. A holding mechanism is provided at both ends of the storage medium (2) and both ends of the composite head (4) to improve impact resistance.

[0005]

According to the present invention, a small-diameter cylindrical storage medium (2) is provided.
With the same storage medium composition, under the condition that the head mechanism is the same and the maximum peripheral speed is the same, the rotational speed can be increased in inverse proportion to the decrease in the diameter. Since the rotation waiting time is inversely proportional to the number of rotations in the average access time to the data of the apparatus, if the small-diameter storage medium (2) is used, the rotation waiting time can be reduced by the diameter ratio of the storage medium (2). As in the present invention, when a plurality of heads are mounted and arranged at equal intervals as the composite head (4), the moving distance during seek of the head can be reduced to 1 / the number of heads. In the average access time of the apparatus, the seek time is generally a constant acceleration under the same driving condition, and the seek time is generally proportional to the square value of the moving distance. In the apparatus of the present invention, the seek time is 1 unit.
/ (Square value of the number of heads). In the apparatus of the present invention, a voice coil motor (6) is provided at an end of a shaft (5) as a head driving method, and a composite head (4) is fixed to the shaft (5). By comparison, the complex arm mechanism is the shaft (5)
And is greatly simplified. Since the driving force from the voice coil motor (6) acts only in the direction of movement of the composite head (4), unlike the winchester system, it has a structure in which extra vibration and moment are unlikely to occur. A voice coil (8) is wound around the shaft (5), and a voice coil (8) is provided in a magnetic gap between a stator internal magnetic pole (7) and an external magnetic pole (6a) of a voice coil motor (6).
The force is generated in the axial direction of the shaft (5) in proportion to the current flowing through the voice coil (8), the shaft (5) is driven, and the composite head (4) fixed to the shaft (5) is moved. By moving, a large number of tracks can be selected in the circumferential direction of the storage medium (2). When the electric conductivity of the shaft (5) is high, a slit is cut in a portion where the coil is wound in the axial direction so as not to function as a short ring. Placing the voice coil motor (6) at both ends of the shaft (5) reduces the load on one motor by almost half, improves the acceleration by almost twice, and halves the average seek time. According to the present invention, a semiconductor element is formed on an IC substrate and used for a selection circuit and an amplification circuit of a head, and the selection circuit is connected to the head mechanism formed on the IC substrate, and a composite head (4) is collectively prepared.
Cable (1) between the composite head (4) and the control board (9)
The number of connection lines 0) is greatly reduced as compared with the case where necessary lines are individually drawn from each head. The drivable length of the voice coil motor (6) is at least twice the head interval,
An adjacent head is sought to the position of a defective head and used in place of the defective head to prevent an increase in an area which cannot be used for the storage medium (2) due to a part of a large number of heads being defective. Is defective, the composite head (4) can be used, and the failure rate of the composite head (4) is reduced. The wiring of the voice coil (8) is connected to the composite head (4), and connected to the head drive circuit of the control board (9) via the cable (10) from the composite head (4) to simplify the wiring. . If the device is mounted on the device including the main control mechanism as well as the storage medium (2) and has a common interface with the outside, the device on which the device is mounted may be different even if the medium and storage capacity of the device are different. , Can be used without change. Further, the composite head (4) and the head drive mechanism are simplified, can be manufactured relatively inexpensively, and can have a simpler mechanism than a device in which the storage medium (2) and the head mechanism are separated. . The storage medium (2) has bearings (1) at both ends.
Since the storage medium (2) is held in 1) and small and lightweight, it can be resistant to impact. In addition, storage medium (2)
The rigidity of the ring (26) sandwiched between the ring (26) and the shaft (3) is reduced, and the impact resistance of the ring (26) can be improved as a method of bending the ring (26). At the same time as lowering the rigidity of the ring (26), a mechanism for restoring the dynamic balance of the storage medium (2) can be provided by mounting a liquid or solid that moves when the balance is out of balance in the storage medium (2). Instead of the bearing (11), a dynamic pressure bearing may be employed to further improve the impact resistance. The composite head (4) is supported from both ends by a boil coil motor (6) via a shaft (5), does not move significantly due to impact, and is filled with a magnetic fluid or the like in the gap of the voice coil motor (6). A damper can be used to improve impact resistance.

[0006]

An embodiment of the present invention will be described with reference to the drawings.
The housing case (1) is an outer shell of the device, protects the inside and holds parts of the device. The storage medium (2) is cylindrical and has a ring (2).
6) a plurality of fixed to the storage medium (2) and a ring (26);
The shaft (3) of the rotating shaft passes through the center hole of the ring (2).
6). The surface of the storage medium (2) has a thin film required for a storage mechanism. Bearings (11) are mounted on both sides of the storage medium (2) on the shaft (3), the storage medium (2) is supported from both ends, and the stator side of each bearing (11) is fixed to the housing case (1). ing. Although not shown, perforated seals for passing the shaft (3) are provided on both sides of the bearing (11) on the stator side to prevent oil leakage from the bearing (11). The seal may be magnetized and filled with a magnetic fluid between the seal and the shaft to prevent oil leakage. A motor (12) is mounted on the end of the shaft (3) to rotate the storage medium (2). The composite head (4) is manufactured as an IC, and integrates a plurality of head mechanisms, an amplifier circuit, and its selection circuit. The composite head (4) is arranged such that the long end of the composite head (4) is close to a position aligned on the same plane as the rotation axis of the storage medium (2). The heads are not shown in the drawing, but are arranged at equal intervals on one surface of the IC substrate at the position of the slider surface (21) of the composite head (4). The composite head (4) and the slider (18) have a groove (20) through which the surface airflow of the storage medium (2) passes. The slider surface (21) except for the groove (20)
The shape is adapted to the surface of the storage medium (2), and the corner is chamfered so as not to be an acute angle. The groove (20) reduces the load on the motor (12), and at the same time, the storage medium (2) rotates as a groove having a narrow inlet and a wide outlet so that a negative pressure is generated around the storage medium. Slider surface (2
1) pressure of the surface effect generated between the storage media (2),
At the position where the negative pressure of the airflow is balanced, it slightly emerges. The error between the slider surface (21) and the curved surface of the storage medium (2) is reduced by reducing the rigidity of the composite head (4), the slider (18) and the shaft (5) within a required value, and being bent by a pressure difference to be absorbed. I do. The cable (10) is bent in a U-shape to absorb vibration during head seek, and is connected to the composite head (4) at a different angle after contacting the shaft (5).
The other end of 0) connects to the control board (9) via a connector (19). Both the composite head (4) and the slider (18) are fixed to a hollow shaft (5). The shaft (5) is square, and the composite head (4) and the slider (1)
8), and the shaft (5) is also used as a winding frame of the voice coil (8). Slider (18)
The plate can be made into a 7-shape, and the groove on the slider surface can be made by pressing. Further, one surface of the shaft (5) may be formed in the same shape as the slider (18) to be used as a substitute. The slider (18) is a plate, and the composite head (4)
, The slider surface may be fixed to the shaft (5) so that the slider surface is separated. The stator of the voice coil motor (6) includes an external magnetic pole (6a), an internal magnetic pole (7), and a magnet (not shown). The voice coil motor (6) is arranged opposite to both ends of the shaft (5). Although not shown, the lead wire of the voice coil (8) is connected to the composite head (4). Connect to the control board (9) via (10). The gap between the external magnetic pole (6a) and the voice coil (7) and the gap between the shaft (5) and the internal magnetic pole (7) are filled with a magnetic fluid and used as a damper for the head, lubrication and cooling. The shape of the magnetic pole is square, preventing rotation of the shaft (5) and keeping the composite head (4) horizontal.
Although not shown, a control circuit and the like are mounted on the control board (9). One end of the control board (9) penetrates the housing case (1), and is exposed in the recess (14) without being exposed to the outside. A terminal (13) is provided at the tip, and the terminal (13) is provided. The device receives power from the outside and exchanges data with the outside. The terminal (13) is formed on the control board (9), but may be a pin-type connector. One terminal of the terminal (13) is cut first when removing the device and comes in contact last when inserting the device, so that the detached state of the device can be detected, and the device can be safely detached from the active utilization device. . Another end of the control board (9) penetrates the housing case (1) and has a write-protect switch.
(16) and an access display device (17) are added. The write inhibit SW (16) is a three-state SW of write enable, write inhibit, and extractable. The SW slider (16a) has a protrusion (28), and the slider (16a) has a protrusion (28). It can be moved only when it is within the area (22), and the projection (28) can be moved with the spring (29).
Hold in one position. From FIG. 3, the slider (16
a) is omitted. When the write-protect SW (16) is in a write-enabled and write-protected state, the key (2) of the slider (16a) is
Part 7) passes through the hole (23) of the housing case (1) and fits with the key hole (25) of the holder (24) for mounting the device,
The device is fixed to a holder (24). Further, the write-protect SW (16) has a mechanism in which one end of the slider (16a) floats up at the position where the removal is possible, and the device can be pulled out using the lift as a handle. The airtightness of the housing case (1) is enhanced by using the through terminal without allowing the control board (9) to directly penetrate the housing case (1). For high-altitude space, the case is completely sealed and the inside is filled with dry gas. The housing case (1) has a groove (15) which defines the orientation of the device when the device is inserted along its long axis. Instead of the groove (15), a method of chamfering a corner at a large angle is also possible.

[0007]

As an example of the present invention, a composite head (4) adopting a cylindrical storage medium (2) having a diameter of 8 mm and a length of 26 mm and having 25 heads arranged at 1 mm intervals. , When compared with a 3.5-inch DISK device of the same technical level and head, the storage medium (2) of the present invention has a diameter of 1/10 under the same maximum peripheral speed. The rotation speed can be increased 10 times,
The average rotation waiting time of the device can be reduced to 1/10. Further, the average moving distance of the head is about 0.4 mm, which can be reduced to 1/20 compared to about 8 mm of the 3.5-inch DISK apparatus, and 1/20 under the same driving condition.
The seek time of the head can be reduced to about 4.5. Unlike the Winchester system of the 3.5-inch DISK device, the composite head (4) is equipped with a voice coil motor (6) at the end of the head mechanism, and the moving direction of the head matches the driving direction of the motor, so that unnecessary vibration and The increase in moment can be reduced, the head mechanism is extremely simplified and lightweight, and the driving conditions are improved, and a seek time of 1/10 or less can be easily realized in combination with the reduction of the moving distance. The structure is simplified by winding the voice coil (8) around the shaft (5). By integrally manufacturing a head and a head selection circuit on an IC substrate as the composite head (4), connection with other components can be simplified, and cost and reliability can be improved even with a large number of beds. Further, the defective rate of the composite head (4) can be reduced by relieving the defective head with the adjacent normal head. Since the apparatus of the present invention employs a storage medium (2) having a small diameter and a short length, the recording area is reduced.
Although it is about 1/30 of the inch DISK device, the volume of the device can be reduced to about 1/30 by itself and the storage capacity / volume ratio is about the same. The same installation space can be obtained by using a plurality of these devices in parallel. Can be equipped with a device having a similar storage capacity. In such a case, each device can be configured to be operated in parallel, and the number of accessible times per hour is proportional to the number of devices. Can be improved. Assuming that the unit price of the device is reduced to about 1/3 by reducing the size, the total price is 10 times and the performance is 300 times, and the price / performance ratio is improved by 30 times. When the storage medium (2) having a diameter of 8 mm to half of 4 mm in this example is adopted as the storage medium (2), the area of the storage medium (2) becomes が, but the volume becomes １ ／, If the apparatus has the same size, four storage media (2) can be mounted, the total storage capacity is doubled, and the rotation waiting time is reduced to half. Composite head (4)
And four sets of motors (12) are required, but voice coil motors and the like can be shared and the total cost is not quadrupled. In the present invention, if a thinner storage medium (2) is employed and a plurality thereof are mounted, In addition, the access speed and storage capacity of the device can be further improved. When the external shape is obtained by adopting the storage medium (2) of this example, the external size can be set to 12 × 20 × 50 mm. At present, this device can realize a storage capacity of about 2 gigabytes and can store two years. Later, 8 gigabytes, 5 years later, 60 gigabytes, and 10 years later, terabytes of storage capacity can be viewed.
Since this device is lightweight and the head does not have a large moving part,
The anti-shock characteristics can be easily improved, and the device can be safely transported with a corner without exposing screws and terminals to the outside. If the outer shape of the housing case (1), the shape of the terminal (13), and the rules are the same, the number of built-in parts increases and the cost becomes extra as compared with a device in which only the storage medium (2) is replaced.
A head mechanism or the like is not required on the side on which the apparatus is mounted, so that the apparatus is simpler, and a single apparatus or a small number of apparatuses are replaced, or conversely, an apparatus in which a large number of apparatuses are constantly operating is less expensive. The storage densities per unit area are increasing rapidly, and they can be adopted in a timely manner, resulting in a device system that is more continuous and more diverse than devices that only exchange media. If a mechanism for converting the IDE standard, the SCSI standard, or the USB standard to the connection standard of the device is interposed, the device can be used similarly to the existing DISK device. At this time, a plurality of the devices can be apparently made into a single device, or a RAID mechanism can be realized to make the device more versatile. Also, U
It is also possible to match the connection standard with the SB standard or the like.

[Brief description of the drawings]

FIG. 1 is a cross-sectional view of the apparatus of the present invention taken along line AA of FIG. 2;

FIG. 2 is a sectional view of the apparatus of the present invention taken along line BB of FIG. 1;

FIG. 3 is a partial cross-sectional view of the device of the present invention taken along line CC of FIG. 2;

FIG. 4 is a plan view of a slider of a write-inhibit SW of the apparatus of the present invention.

[Explanation of symbols]

 (1) Housing case (2) Storage medium (3) Shaft (4) Composite head (5) Shaft (6) Voice coil motor (6a) External magnetic pole (7) Internal magnetic pole (8) ) Is a voice coil (9) is a control board (10) is a cable (11) is a bearing (12) is a motor (13) is a terminal (14) is a depression (15) is a groove (16) is a write-protect SW (16a) ) Is a slider (17) is an access display device (18) is a slider (19) is a connector (20) is a groove (21) is a slider surface (22) is a slider area (23) is a hole (24) is a holder (25) Is a key hole (26) is a ring (27) is a key (28) is a protrusion (29) is a spring

Claims (3)

[Claims] An apparatus for recording and reproducing data on a storage medium (2) using a composite head (4) equipped with a number of heads using a rotating cylindrical or columnar storage medium (2). An apparatus using a voice coil motor (6) for movement and using a storage medium (2) having a diameter of 20 mm or less. 2. The apparatus according to claim 1, wherein a head switching circuit and an integrated head (4) in which each recording / reproducing head is formed are used on an IC (hereinafter, integrated circuit) substrate. 3. A voice coil motor (6) according to claim 1, wherein a voice coil (8) is wound around a hollow shaft (5).