Hatchett, Michael Robert, San Jose, California 95120, US; Heath, John Stewart, Winchester Hampshire SO22 4JB, GB; Lee, Hubert Chew, San Jose, California 95120, US; Row, Eun Kyoung, San Jose, California 95131, US; Spencer, Roger Dale, San Jose, California 95120, US; Workman, Michael Lee, San Jose, California 95120, US
The present invention relates to disk drive systems.
One of the principle components of a computer system is a place to
store data. Typically computer systems employ a number of storage means to store
data for use by a computer system. For example, a computer system can store data
in a peripheral storage device referred to as a disk drive or direct access storage
A disk drive or DASD includes one or more disks which appear similar
to records utilized with a record player or compact disks (CD) which are utilized
with a CD player. The disks are stacked on a spindle for rotary motion in parallel
planes, much like records. In a disk drive, however, the disks are mounted to the
spindle and spaced apart so that the separate disks do not touch each other.
Such data storage devices employing rotating magnetic or optical
media disks are well-known for high capacity, low cost storage of data. Such disks
typically have a multiplicity of concentric data track locations formed on one
or both surfaces, each capable of storing useful information. The information stored
in each track is accessed by a transducer head which is moved among the tracks
during track seeking operations and which is maintained in alignment with the track
during read only and/or read/write track following operations of the device. Typically
one or more transducer heads are provided for each data storage surface. The electro-mechanical
assembly for rotation of the disk relative to the head and for moving the head
radially relative to the disk surface for track accessing purposes is referred
to as the head and disk assembly (HDA). Each HDA may include a plurality of magnetic
storage disks mounted on a spindle. A control mechanism is provided in order to
maintain the head within the boundaries of each data track, and may take the form
of detents provided by a stepping motor, or by a continuously positionable actuator
operating within a closed loop servo, or a time-sampled servo. Additionally, an
interface device is required for connection of the HDA to a controller and for
communication between the disk drive and the computer system. Typically, a standardized
interface is utilized, for example, the Small Computer Synchronous Interface (SCSI).
Today's technology relating to data storage is marked by continuing
trends towards standardization and towards increased storage capacity, reduced
data storage device weight and size, and reduced power consumption. Standardization
in size, referred to as form factor, and in interface compatibility is being pursued
by manufacturers of both desktop systems such as personal computer (PC) and workstation
systems and larger computing systems. Thus, disk drives having differing capabilities
and capacities provided in standard form factors and plug-in configurations by
several different manufacturers may be used interchangeably in different PC's,
for example, in standardized plug-in slots provided by the PC manufacturers.
Increasing system storage capacity while reducing disk drive size
requires careful balancing of the reduction of the area of the storage medium,
i.e., the area of the disk surface, against the corresponding reduction in storage
capacity. A typical solution is to increase the number of disks per spindle and/or
increase the number of disk drives. On a large scale, large numbers of relatively
small disk drives are mounted in drawers to provide high storage capacity while
taking advantage of common power supplies and cooling facilities, for example,
to achieve an overall reduction in power requirements. However, for a PC, for
example, a user is limited to adding individual disk drives in the standard form
factor slots provided by the PC manufacturer or by adding relatively expensive
SUMMARY OF THE INVENTION
According to the present invention, there is provided a disk drive
assembly comprising a unitary assembly having: a mounting frame; a plurality of
head-disk assemblies (HDAs) for storing information, said HDAs being mounted on
one side of said mounting frame; control means coupled to each of said HDAs for
providing control signals; and data connection means for coupling information to
and from said HDAs in response to said control signals.
Preferably, disk drive assemblies according to the present invention
include at least two HDAs packaged in an industry-standard form factor which is
interchangeable with disk drives of the same form factor in a computer system in
slots and racks of the same form factor as provided by the computer system manufacturers.
It is preferred to provide a disk drive assembly including at least
two HDAs and further including a single controller board. It is also preferred
for the HDAs to be separately addressable via a common interface connector.
A preferred embodiment of the present invention provides a disk drive
assembly in a five and one-quarter (5 1/4) inch disk drive form factor which includes
two three and one-half (3 1/2) inch form factor HDAs mounted on a common frame.
This two-drive embodiment of the invention has as great or greater storage capacity
than a like-sized 5 1/4 inch disk drive while consuming less power. Additionally,
since the spindle drive motor for a 3 1/2 inch disk drive is significantly smaller
than the spindle motor for a 5 1/4 inch disk drive and since startup of the two
drives can be staggered, less startup current is required.
Thus, a disk drive assembly according to the present invention preferably
comprises a mounting frame or base having a length approximately equal to the length
of a selected disk drive form factor and a width approximately equal to the width
of the selected disk drive form factor and having two HDAs mounted on a top side
thereof, each of the HDAs having a length approximately equal to the width of the
selected disk drive form factor and a width approximately equal to one-half of
the length of the selected disk drive form factor. Such a multiple disk drive
assembly further includes a single, common controller board mounted on the bottom
side of the base underlying the two HDAs and having common power and interface
connectors mounted at a rear edge of the controller board. A common jumper or option
block may also be mounted at the rear edge of the controller board, providing for
setting separate addresses for each of the HDAs. Top and bottom covers may be attached
to the top and bottom sides of the base, respectively, to form upper and lower
enclosures enclosing the HDAs and the controller board and providing a disk drive
assembly unit having overall outside dimensions approximately equal to the selected
disk drive form factor.
A multiple disk drive assembly according to one embodiment of the
present invention provides a 5 1/4 inch disk drive form factor assembly having
two 3 1/2 inch disk drive form factor HDAs internally mounted on a rigid frame
and accessible via a common industry-standard interface. Both the interface and
power connectors and the frame mounting hole patterns are industry standard to
provide interchangeability with 5 1/4 inch form factor disk drives provided by
manufacturers for use in computer systems, such as desktop personal computers,
for example. A single electronic controller board is shared by the two HDAs to
provide all controller functions and power distribution for the HDAs as well as
data transfer to and from the data channel for each HDA. The controller board
may be implemented with either SCSI or IPI (intelligent printer interface) interfaces
in single-ended or differential versions. Top and bottom covers provide the assembly
with upper and lower enclosures with sufficient clearance around the HDAs and controller
board, respectively, to provide efficient cooling of the components utilizing the
cooling provided by the host computer system. A spring vibration damper device
is utilized to minimize both external and internal vibration and shock effects
to the HDAs. The assembly is fully enclosed with metal covers to provide electromagnetic
compatibility and radio frequency interference protection.
This embodiment of the present invention provides a two-drive array
in a single assembly within the constraints of a 5 1/4 inch industry-standard
form factor having common electronics and accessible via a common interface connector.
The performance of the array may be optimized for various configurations without
forcing a user of the assembly to rewrite or amend their computer operating system
software or providing special controllers or interfaces. For example, the two-drive
assembly provides two independently addressable disk drives which may be utilized
as two separate data storage files or in which one drive may be reserved as a "hot"
spare while the other drive is used for data storage. Alternatively, the two-drive
array may be configured to provide a "single" drive with the media rate effectively
doubled or as one drive with multiple copies of data (mirrored data).
BRIEF DESCRIPTION OF THE DRAWINGS
The present invention may be more fully understood from the following
detailed description of the preferred embodiments, reference being made to the
accompanying drawings, in which like reference numerals indicate like parts and
Fig. 1 is an exploded view in perspective of a disk drive system according
to the present invention;
Fig. 2 is a perspective view of the disk drive system in Fig. 1 in partially
Fig. 3 is a perspective view illustrating the disk drive system of Fig. 1 in
fully assembled form;
Fig. 4 is a rear view of the disk drive system shown in Fig. 3 illustrating
controller board connectors and cover cooling vents;
Fig. 5 is a top view of the interior of a head/disk assembly suitable for use
in the disk drive system shown in Fig. 1;
Fig. 6 is an exploded view in perspective of the head/disk assembly shown in
Fig. 7 is a conceptual block diagram of electrical, control and communications
distribution circuitry employed in the disk drive system shown in Fig. 1;
Fig. 8 is a plan view of a jumper block for a controller board forming part
of the circuitry of Fig. 7; and
Fig. 9 is a partially exploded view in perspective of a second embodiment of
a disk drive system of the present invention.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS
Referring to Figs. 1 and 2, Fig. 1 is an exploded view of a preferred
embodiment of the disk drive system according to the principles of the present
invention. A multiple disk drive system 10 comprises two head and disk assemblies
(HDA) 11 and 13 mounted on the top side a mounting frame or base 15, a common controller
board 17 mounted on the bottom side of the base 15 and including a top cover 19
and a bottom plate 21 attached to the top and bottom of the base 15, respectively,
to provide an enclosure for the two HDAs 11 and 13 and the controller board 17.
Each of the HDAs 11, 13 is enclosed in a separate housing 23, 25, respectively,
which provides a rigid frame for mounting the spindle and attached disks, the spindle
motor and the actuator and read/write transducer head assembly as will be described
in greater detail below with reference to Figs. 5 and 6. The base 15 includes a
mounting bracket 27 for mounting the HDAs 11 and 13 on the base. The HDAs 11 and
13 are mounted side-by-side on the base 15 and attached to bracket 27, for example,
by stud 31 engaging slot 29 and secured by clip 35. Shock absorbing devices, such
as rubber shock absorber 33, for example, are provided at the HDAs 11 and 13 attachment
points to provide mechanical isolation from the base 15. Similarly, studs 37 and
39 engage slots 41 and 43, respectively; additional stud and clip combinations
(not shown) or other suitable attachment means complete the attachment of the HDAs
11, 13 to the bracket 27.
The base 15 also includes a mounting bracket 49 for mounting a vibration
damping device 47. The vibration damper 47 is attached to the bracket 49 in such
a manner that a force is applied to the front side 51 of each HDA housing 23, 25
when the HDAs 11 and 13 are mounted on the base 15. The vibration damper device
47 comprises a stainless steel spring providing a controlled force acting on the
HDA housings. The stainless steel spring is coated with a low-wear, insulating
material, such as XYLAN 1010, to provide electrical insulation and a consistent
coefficient of friction between the HDA housings 23, 25 and the vibration damper
47. The vibration damper 47 is rigidly secured to the mounting bracket 49 by bolts
and nuts or other well-known manner.
When mounting two or more HDAs on a common frame. base 15, for example,
the frame must be sufficiently rigid to minimize effects due to both external vibration
and shock and to vibrational forces generated by the HDAs themselves. For example,
rotational torque generated by the rotating magnetic disks is transmitted to the
HDA housing causing low frequency vibrations. This vibration may also be transmitted
to adjacent HDAs via the mounting frame. One result of such vibration is track
misregistration greatly increasing the demands on the head tracking servo system.
The use of dampening systems, such as the vibration dampening device 47, for example,
reduces the rigidity and stiffness requirements of the mounting frame resulting
in a lighter, less massive frame and allowing a greater choice of materials for
fabrication of the mounting frame. In the preferred embodiment, the vibration damper
47 applies a frictional dampening force in the range of 0.8 kilograms to 2.0 kilograms
to the front side 51 of each HDA 11, 13. The frictional force applied by the vibration
damper 47 minimizes the low frequency resonance of the individual HDAs 11, 13 and
stiffens the HDA shock mounts, shock absorber 33, for example, to minimize transmission
of vibration and shock between adjacent HDAs.
The controller board 17 comprises a multi-layer printed circuit board
having various electronic components mounted thereon and provides the required
electronic circuitry to facilitate operation and control of the HDAs 11 and 13,
couple information to and from the HDAs and to interface with a host computer system.
The controller board 17 also includes a power connector 53, a controller interface
connector 55 and a jumper block or options connector 57 mounted thereon at the
rear end of the board. Cables 59 connect the controller board to the HDAs 11 and
13 and to the data channel boards 61 and 63, respectively, mounted on the HDA
housings. The controller board 17 is described in greater detail below with reference
to Fig. 7.
Referring now also to Figs. 3 and 4, the controller board 17 is mounted
on the bottom side of the base 15. Slots 45 in the front edge of the board 17 engage
corresponding studs or clips formed in the bottom side of the base 15 (not shown).
The board 17 is retained in position by a rear mounting bracket 65 which engages
the board at its rear edge and is secured to the base 15 in slots 67 by screws
or bolts and nuts 69 through tabs 71. The base 15 includes downwardly extending
side and front walls 73 and 75, respectively, which form an enclosure for the
controller board 17 when the bottom plate 21 is attached to the base 15. The front
wall 75 includes a pattern of air or ventilation holes formed therethrough to provide
a cooling air inlet for the controller board components.
The top cover 19 is attached to the base 15 by slots 79 in engagement
with screws or bolts and nuts 83 through holes 81. The bottom plate 21 is attached
to the bottom side of the base 15 by tabs 85 in engagement with corresponding slots
(not shown) in the lower portion of the base front wall 75 and maintained in position
by screws or bolts and nuts 69 through slots 77 and 67 at the rear of the base.
When completely assembled, the two HDAs 11 and 13 are enclosed in an upper enclosure
above the base 15 and the controller board 17 is enclosed in a lower enclosure
below the base 15. The front and rear walls 87 and 89, respectively, of the cover
19 have a pattern of air or ventilation holes formed therethrough to allow cooling
of the HDAs and associated components. The rear of the lower enclosure is open
allowing cooling air to flow through the enclosure and to provide access to the
controller board connectors 53, 55 and 57.
The assembled multiple disk drive system, as shown in Fig. 4, forms
a complete plug-in disk drive unit 90 having overall dimensions of approximately
3.25 inches (82.5 millimeters (mm)) in height, 5.75 inches (146.0 mm) in width
and 8.25 inches (209.5 mm) in length, the approximate dimensions of the industry-standard
form factor for a five and one-quarter (5 1/4) inch disk drive. An industry-standard
pattern of mounting holes are provided which allows the disk drive unit 90 to be
mounted in six different positions. The controller board connectors 53, 55 and
57 comprise industry-standard components. The disk drive unit 90 is completely
interchangeable with other industry-standard 5 1/4 inch form factor disk drives
and can be used in any 5 1/4 inch slot or rack in a computer, such as a PC for
The HDAs 11 and 13 utilized in the preferred embodiment described
above have a length approximately equal to the width of a 5 1/4 inch disk drive
form factor and a width approximately equal to one-half the length of a 5 1/4 inch
disk drive form factor which are the approximate dimensions of a three and one-half
(3 1/2) inch disk drive form factor. Figs. 5 and 6 are a top plan view and an exploded
view in perspective, respectively, of an HDA for a 3 1/2 inch form factor disk
drive which is suitable for use in the multiple disk drive system 10 of the present
Referring now to Figs. 5 and 6, a disk drive 100 includes a housing
101, and a housing cover 103 which, after assembly, is mounted on base 15 within
bracket 27 (as shown in Fig. 1). Rotatably attached within the housing 101 on an
actuator shaft 117 is an actuator arm assembly 119. One end of the actuator arm
assembly 119 includes an E block or comb like structure 121 having a plurality
of arms 123. Attached to the separate arms 123 on the comb or E block 121 are load
springs 125. Attached at the end of each load spring is a slider 127 which carries
a magnetic transducer head (not shown). On the other end of the actuator arm assembly
119 opposite the load springs 125 and the sliders 127 is a voice coil 129.
Attached within the housing 101 is a pair of magnets 131. The pair
of magnets 131 and the voice coil 129 are key components of a voice coil motor
which applies a force to the actuator assembly 119 to rotate it about the actuator
shaft 117. Also mounted within the housing 101 is a spindle shaft 133. Attached
to the spindle shaft 133 are a number of magnetic storage disks 135. A spindle
motor (not shown in Fig. 6) is coupled to the spindle shaft 133 for rotatory motion
of the spindle shaft at a selected speed. As shown in Fig. 6, eight disks 135 are
attached to the spindle shaft 133 in spaced apart relation. When assembled, the
separate arms 123 extend between the disks 135 in such a manner that the magnetic
head at the end of each load spring 125 is closely adjacent a surface of one of
the disks. During storing and retrieving (write/read) of information, the voice
coil motor responsive to control signals causes the magnetic head to be moved across
the surface of the disk.
Referring now also to Fig. 7, the single electronics controller board
or card 17 is mounted in the lower enclosure below the two HDAs 11 and 13 (as shown
in Fig. 1) and is shared by the two HDAs. For the purposes of the description of
the controller board 17, the two HDAs 11 and 13 will be referred to as drive A
and drive B, respectively. Each drive A, B is electronically controlled by an interface
microprocessor, a servo control microprocessor, several logic modules, digital/analog
converters and various drivers and receivers and associated circuitry. With the
exception of the data channel circuitry which is mounted on a separate channel
board 137 (as shown in Fig. 6) for each drive A, B, all of the control circuitry
and components are mounted on the controller board 17. While some of the components
physically may be shared by the two drives A, B for efficiency and parts reduction,
logically, the controller board 17 is divided into halves, one-half A, 149, providing
control for drive A and the other half B, 151, provide control for drive B.
Since the control electronics for both of the drives is essentially
identical, both in operation and composition, the operation of only one will be
The servo microprocessor (not shown) for each drive A, B generates
all actuator servo and spindle motor control signals with the exception of starting
and stopping of the spindle. The servo microprocessor controls the spindle motor
speed via a closed loop servo system and performs the spindle synchronization function.
The servo microprocessor provides spindle motor control signals for its respective
drive on lines 141 and 143, respectively. The spindle is driven directly by an
in-hub, brushless DC drive motor 153 receiving its power from the controller board.
Dynamic braking is utilized to quickly stop the spindle upon receipt of a stop
The actuator 155 is a swing-arm assembly driven by a voice coil motor
having the read/write transducer heads mounted opposite the voice coil motor. The
servo microprocessor initially conducts a power-up sequence and calibrates the
actuator servo system. All actuator control signals providing closed loop control
of transducer head positioning and tracking on the disk surface are generated by
the servo microprocessor. A dedicated servo disk surface and head provides feedback
to the actuator servo to maintain the read/write heads centered over the desired
track on the disk. The servo microprocessor monitors the actuator position and
determines a target track for a seek operation. Utilizing stored velocity profiles,
the voice coil motor power amplifier driver is controlled to drive the actuator
to a desired target track. During seek operations, the dedicated servo head provides
track crossing information to the servo. Responsive to appropriate input conditions,
the servo microprocessor generates control signals for accessing servo signal
gating, recalibration, track following and error detection and recovery. The servo
microprocessor provides servo control signals to its respective actuator servo
via lines 145 and 147, respectively.
The interface microprocessor (not shown) controls and interprets
all interface signals between the host computer system controller and its respective
drive. The interface microprocessor generates the spindle start and stop signals
for its respective drive. All data processing circuitry and logic including coding
for write and detection and decoding operations, error detection and error correction
is implemented on a separate data channel board 137 (as shown in Fig. 6) for each
drive A, B coupled to its microprocessor via lines 139A and 139B, respectively.
The interface microprocessor controls the transfer of data between its respective
drive A, B and the host computer system, read/write access of the disk media and
disk defect management and error recovery. Additionally, the interface microprocessor
performs diagnostics and provides momitoring of the spindle status.
The multiple disk drive unit 90 is coupled to the host computer system
via the connectors 53, 55 and 57 mounted at the rear edge of the controller board
17. The controller board may use ANSI standardized SCSI or IPI interfaces in either
differential or single-ended versions. In the preferred embodiment, single-ended
buffered SCSI is utilized and the interface signal connector 55 comprises a 50-pin
connector meeting ANSI/SCSI specifications (Molex part no. 70246 is suitable for
this purpose). The pin assignments are given in Table I. The Dc power connector
53 comprises a 4-pin connector which couples + 12 volt and + 5 volt power to the
board 17 and provides two system grounds.
Signal Name Conductor Pin Number Signal Name GROUND12-DB(0) GROUND34-DB(1) GROUND56-DB(2) GROUND78-DB(3) GROUND910-DB(4) GROUND1112-DB(5) GROUND1314-DB(6) GROUND1516-DB(7) GROUND1718-DB(P) GROUND1920GROUND GROUND2122GROUND OPEN2324OPEN OPEN2526TERMPWR OPEN2728OPEN GROUND2930GROUND GROUND3132-ATN GROUND3334GROUND GROUND3536-BSY GROUND3738-ACK GROUND3940-RST GROUND4142-MSG GROUND4344-SEL GROUND4546-C/D GROUND4748-REQ GROUND4950-I/O TABLE I
The options block 57 comprises a 26-pin jumper block 57 as shown in
Fig. 8. Pins A1-A6 and B1-B6 are used to select and set the respective drive A,
B SCSI device address (SCSI ID). The desired address is set utilizing a jumper
or shorting block 161, shunting one or more of the bit pins to ground. Pin configuration
for a desired drive address is defined in Table I. Pins A9, A10 and B9, B10 control
spindle synchronization and the remaining pins control spindle motor start and
term power for the respective A and B drives.
The multiple disk drive unit 90 provides a two-drive array utilizing
a common controller board and a common interface connector in a 5 1/4 disk drive
form factor. The two-drive array may be controlled in various configurations to
provide optimum performance or user desired features. The configuration of the
preferred embodiment comprises two separately addressable independent disk drives
accessed through a common SCSI connector. The address (SCSI ID) of each drive A,
B is set at the jumper block 57 as described above. A user then may use one drive,
drive A, for example, while reserving the other drive as a "hot" spare. Alternatively,
both drive A and drive B may be used for continuous data storage thus providing
greater storage capacity than provided by a single 5 1/4 inch drive while reducing
the power and cooling requirements and the cables, connectors, etc., required for
two 3 1/2 inch drives.
Referring now to Fig. 9, a second preferred embodiment of a multiple
disk drive system according to the principles of the present invention is shown.
A multiple disk drive system 200 comprises a base 201 having four HDAs 203, 205,
207 and 209 mounted on an upper side thereof and a single controller board 211
providing the circuitry and components required for the operation and control of
the four HDAs. Cable connector pairs 213, 215, 217 and 219 are provided to couple
power and control signals to and transfer data to and from the HDAs 209, 203, 205
and 207, respectively. Power connector 221 and interface connector 223 are mounted
at the rear edge of the controller board 211 to couple the multiple disk drive
system 200 to a host computer system. As described above with reference to Fig.
1, the controller board 211 is mounted on the bottom side of the base 201 beneath
the HDAs. Similarly, a top cover 227 and a bottom cover (as shown in Fig. 1) are
attached to the base 201 forming upper and lower enclosures which enclose the
four HDAs and the controller board, respectively. When assembled, a complete disk
drive unit 90 is formed (as shown in Fig. 4) which provides an array of four separately
addressable, independent disk drives accessible via a common interface connector.
In the preferred embodiment as described above with reference to
Fig. 9, the disk drive unit 90 has approximately the overall dimensions of a 5
1/4 inch disk drive form factor (as shown in Fig. 4). Each of the four HDAs 203,
205, 207 and 209 mounted on base 201 has a length approximately equal to one-half
the length of a 5 1/4 inch drive form factor and a width approximately equal to
one-half the width of a 5 1/4 inch disk drive form factor, which length and width
approximate the dimensions of a two and one-half (2 1/2) inch disk drive form factor.
While the invention has been particularly shown and described with
reference to various preferred embodiments thereof, it is understood by those
skilled in the art that the invention is not to be limited to the disclosed embodiments,
but that various modifications in the form and details may be made therein without
departing from the spirit and scope of the appended claims.
A disk drive system (10) comprising a unitary assembly having:
a mounting frame (15);
a plurality of head-disk assemblies (HDAs) (11, 13) for storing
information, said HDAs being mounted on one side of said mounting frame;
control means coupled to each of said HDAs for providing control
data connection means (55, 57) for coupling information to
and from said HDAs in response to said control signals.
A disk drive system as claimed in claim 1 further comprising a first cover
(19) having substantially the same dimensions as said mounting frame and engaged
with said mounting frame enclosing said plurality of HDAs mounted thereon, said
first cover providing a controllable environment between said mounting frame and
said first cover.
A disk drive system according to claim 2, wherein opposing forward and rear
sides (87 and 89 respectively) of said first cover each have at least one aperture
formed therethrough for inflow and outflow of a cooling medium thereby to provide
cooling for components- enclosed by said first cover.
A disk drive system as claimed in any one of claims 1 to 3 further comprising
a common controller board (17) mounted on the opposite side of said mounting frame
to said HDAs, said control means and said data connection means being mounted on
said controller board.
A disk drive system as claimed in claim 4 further comprising a second cover
(21), said second cover having substantially the same dimensions as said mounting
frame, said mounting frame having at least two opposing side walls (73) extending
from opposing sides thereof, said second cover engaging said opposing side walls
for enclosing said common controller board.
A disk drive system as in claim 5 wherein said mounting frame further includes
a forward wall (75) having a pattern of cooling holes formed therethrough, the
enclosure formed by engagement of said second cover with said side and forward
walls being open at a rear side for providing access to said common controller
board and flowthrough for a cooling medium.
A disk drive system according to any one of claims 4 to 6 wherein said common
controller board includes address means mounted thereon and coupled to said control
means and said data connection means for setting a separate address for each of
said HDAs, each said HDA being independently addressable.
A disk drive system as in claim 7 wherein said address means comprises a jumper
block (57) for setting separate addresses for each of said HDAs.
A disk drive system as in any one of claims 4 to 8 wherein said common controller
board includes at least one connector mounted thereon, said connector being common
to said HDAs, said connector providing cable connections for coupling said common
controller board to a host computer system.
A disk driver system as in claim 9 wherein said common controller board includes
a common power connector (53) mounted thereon for coupling said common controller
board to a host power source, and a common interface connector (55) mounted thereon
for coupling said common controller board to a host controller.
A disk drive system according to any one of the preceding claims wherein each
said HDA further comprises data channel means (61, 63) coupled to said data connection
means for storing and retrieving information on and from the one or more magnetic
storage disks (135) which comprise each HDA.
A disk drive system according to any one of the preceding claims wherein the
mounting frame has a length approximately equal to the length of a first selected
industry-standard form factor disk drive and a width approximately equal to the
width of said first selected industry-standard form factor disk drive.
A disk drive system according to claim 12 wherein each of said HDAs has dimensions
substantially equal to an HDA for a selected industry-standard form factor disk
drive which is different from said first selected form factor.
A disk drive system according to claim 12 or claim 13 wherein the first selected
industry-standard form factor is the 5 1/4 inch form factor.
A disk drive system according to any one of the preceding claims having vibration
damper means (47) mounted on said mounting frame for coupling a force to each of
said HDAs for minimizing the effects of shock and vibration on the operation of
said disk drives.
A disk drive system as in claim 15 wherein said vibration damper means comprises
spring means for applying a frictional force to each of said HDAs.
A disk drive system as in claim 16 wherein said spring means is coated with
a layer of a low-wear, electrically insulating material for electrically insulating
said spring means from said HDAs and for providing a selected coefficient of friction
between said spring means and said each HDA at the point of contact between the
spring means and the HDA.