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US3882473A - Magnetic disk storage file - Google Patents

Magnetic disk storage file Download PDF

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Publication number
US3882473A
US3882473A US020781A US2078170A US3882473A US 3882473 A US3882473 A US 3882473A US 020781 A US020781 A US 020781A US 2078170 A US2078170 A US 2078170A US 3882473 A US3882473 A US 3882473A
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US
United States
Prior art keywords
post
disk storage
magnetic disk
storage file
head assemblies
Prior art date
Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
Expired - Lifetime
Application number
US020781A
Inventor
Henry G Hoehmann
Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.)
International Business Machines Corp
Original Assignee
International Business Machines Corp
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Filing date
Publication date
Application filed by International Business Machines Corp filed Critical International Business Machines Corp
Priority to US020781A priority Critical patent/US3882473A/en
Priority to JP46001641A priority patent/JPS5113565B1/ja
Priority to FR7106541A priority patent/FR2083973A5/fr
Priority to BE763146A priority patent/BE763146A/en
Priority to CA106,852,A priority patent/CA950580A/en
Priority to DE2112156A priority patent/DE2112156C3/en
Priority to GB2053671A priority patent/GB1331818A/en
Application granted granted Critical
Publication of US3882473A publication Critical patent/US3882473A/en
Anticipated expiration legal-status Critical
Expired - Lifetime legal-status Critical Current

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    • G—PHYSICS
    • G11—INFORMATION STORAGE
    • G11B—INFORMATION STORAGE BASED ON RELATIVE MOVEMENT BETWEEN RECORD CARRIER AND TRANSDUCER
    • G11B5/00—Recording by magnetisation or demagnetisation of a record carrier; Reproducing by magnetic means; Record carriers therefor
    • G11B5/48—Disposition or mounting of heads or head supports relative to record carriers ; arrangements of heads, e.g. for scanning the record carrier to increase the relative speed
    • G11B5/54—Disposition or mounting of heads or head supports relative to record carriers ; arrangements of heads, e.g. for scanning the record carrier to increase the relative speed with provision for moving the head into or out of its operative position or across tracks
    • G11B5/55—Track change, selection or acquisition by displacement of the head
    • G11B5/5521—Track change, selection or acquisition by displacement of the head across disk tracks
    • G—PHYSICS
    • G11—INFORMATION STORAGE
    • G11B—INFORMATION STORAGE BASED ON RELATIVE MOVEMENT BETWEEN RECORD CARRIER AND TRANSDUCER
    • G11B23/00—Record carriers not specific to the method of recording or reproducing; Accessories, e.g. containers, specially adapted for co-operation with the recording or reproducing apparatus ; Intermediate mediums; Apparatus or processes specially adapted for their manufacture
    • G11B23/02—Containers; Storing means both adapted to cooperate with the recording or reproducing means
    • G11B23/03—Containers for flat record carriers
    • G11B23/032—Containers for flat record carriers for rigid discs
    • G11B23/0323—Containers for flat record carriers for rigid discs for disc-packs
    • G—PHYSICS
    • G11—INFORMATION STORAGE
    • G11B—INFORMATION STORAGE BASED ON RELATIVE MOVEMENT BETWEEN RECORD CARRIER AND TRANSDUCER
    • G11B5/00—Recording by magnetisation or demagnetisation of a record carrier; Reproducing by magnetic means; Record carriers therefor
    • G11B5/48—Disposition or mounting of heads or head supports relative to record carriers ; arrangements of heads, e.g. for scanning the record carrier to increase the relative speed
    • G11B5/49—Fixed mounting or arrangements, e.g. one head per track
    • G11B5/4969—Details for track selection or addressing
    • G—PHYSICS
    • G11—INFORMATION STORAGE
    • G11B—INFORMATION STORAGE BASED ON RELATIVE MOVEMENT BETWEEN RECORD CARRIER AND TRANSDUCER
    • G11B5/00—Recording by magnetisation or demagnetisation of a record carrier; Reproducing by magnetic means; Record carriers therefor
    • G11B5/48—Disposition or mounting of heads or head supports relative to record carriers ; arrangements of heads, e.g. for scanning the record carrier to increase the relative speed
    • G11B5/58—Disposition or mounting of heads or head supports relative to record carriers ; arrangements of heads, e.g. for scanning the record carrier to increase the relative speed with provision for moving the head for the purpose of maintaining alignment of the head relative to the record carrier during transducing operation, e.g. to compensate for surface irregularities of the latter or for track following
    • G11B5/60—Fluid-dynamic spacing of heads from record-carriers
    • G11B5/6005—Specially adapted for spacing from a rotating disc using a fluid cushion

Definitions

  • ABSTRACT A magnetic disk storage file employs a plurality o: magnetic transducers for each recording disk surface and at least one transducer is associated with eacl data track.
  • the transducer assemblies are supported by racks. which are mounted in stacked fashion tc pivotableposts.
  • the posts are fixed in a precise posi tion relative to the true axis of the spindle on which the storage disks are mounted for rotation.
  • the posts are pivotable so that the transducer assemblies and racks may be retracted for easy replacement. and returned to the same precise position and alignment relative to the data disk surface. whereby each transducer bears the same relation to its associated data track as it had prior to retraction.
  • transducing head disk fi erein two or more head transducin elements or flux-sensing nonmagnetic gaps. which are elements can be located over each data track and z uniformly spaced d li d fmscanning di lt) specific angular positions around the disk circumfei data tracks.
  • a further object is to provide a fixed head t'ile conti uration which includes means for maintaining a "clca air environment within the machine. when in opera tion or when being serviced.
  • a fixed head. fixed dis file includes a plurality olspaced coasially aligne magnetic disks. and a plurality of head assemhlit mounted to racks. which in turn are supported h pivotablc post structures.
  • the post structures allow th head assemblies to be simultaneously moved to pos tions adjacent to discrete record tracks on the disks; t be simultaneously pivoted away from the disks so th: certain head assemblies may be removed and rcplacct without displacement of the other heads or the disk liy the same token. the disks may be interchanged witl out affecting the head assemblies or their positions. I this tuanner. each head assembly and transducer Llt ment. or its replacement. will always hear the same Pt sition and attitude relative to its associated disk surl'ac and track.
  • one common circu Presently known magnetic disk storage tiles employ a multiplicity ol magnetic disks. which cooperate with magnetic transducers or heads for recording and playback ol' data.
  • the head assemblies may be of the accessing type. which are actuated radially relative to the disk surface to seek out selected tracks for recording 3 and retrieval ol'data.
  • the random access actuator-type file may use one magnetic head assembly for each disk surface. which is an economical arrangement. but does not achieve the fast access capability that may be realized il'cach data track has a fixed transducer associated 35 therewith.
  • he l card may be connected to a multiplicity of transduct relative to an associated track. and then individually ckmcms Sn hm during finding playback adjust the other head assemblies radially. while the 1 m f rh elements will be operative with disks were rotating and the head assemblies were opcrcircuit Anmhcr m i "w i -i f dug-c illlVL. ill UHlCY it!
  • FIG. I is an isotnctric view. partly b k away. t.
  • FIG. 3 is an isotnctric view of a post structure utililt entire area and prcssuri/ing the interior witlra clean in the novel assembly;
  • FIG. 4 is a rear plan view of a portion of the post structure
  • FIG. 5 is a side elevation schematic view. partly broken away. illustrating the relation between the disk drive spindle. the support racks and mounted heads. and the pivotable post supporting such head racks;
  • HO. 6 is a schematic plan view. partly in block. depicting the head racks. electronic circuit card. and head selection circuitry;
  • FIG. 7 is an exploded view representing the relationship between the head racks and an associated disk. and the post and electronic curd structures. partially shown;
  • FIG. 8 is an enlarged isometric view of a head rack support
  • FIG. 9 is a schematic representation of the filtration and temperature control system utilized in this invention.
  • a magnetic disk storage file structure including a substantially square housing or cage 10. in which a drive shaft or spindle i2 is centrally located.
  • a stack of spaced magnetic disks 14 (see FIGS. 5, 9) or a disk pack is mounted to the spindle l2. and rotated relative to magnetic transducers 16 for recording or playback of data.
  • the transducers or head assemblies 16 are fixed (in rack supports 50) relative to the disk surfaces during operation of the storage file. so that each data track has one associated transducer. or more. cooperating therewith. in a fixed head file type. one or more of the rack supports 50 or disks may be removed conveniently for re placement purposes. as a result of wear or defects.
  • post structures l8 (shown enlarged and in greater detail in FIG. 3) that support the head assemblies are positioned precisely at predetermined locations relative to the spindle 12. to which the storage disks l4 are coaxially mounted.
  • a hub tool 20 (see FIGS. 2a. b) is seated to a flange 22 of the spindle l2. centered to the spindle by a collar formed in a recess at the top of the spindle. and fastened to the spindle by bolting. for example.
  • a fixture 24. having a depressihle spring-loaded pin 26. is positioned in a keyed recess 28 in the top surface of the housing l0.
  • the hub tool 20 and rotary spindle 12 are manually rotated. until the pin 26 engages an aperture 30a or 30b in the hub tool periphery. At this time. the hub tool is locked in a stationary indexed position. if positioned by locking the pin 26 in aperture 300. the hub tool will serve to locate and align two post structures at the rear corners of the cage and on the other hand. ifaperture 30b is engaged by the pin 26. two post structures at the front corners of the cage may be located and aligned.
  • a set of vertically spaced dowel pins 32-1 for one post position (or 32-2 for another post position. preferably displaced 90). that project from the hub tool. are meshed with vertically spaced guide holes 34 (only the upper one being shown in FIG. 4) formed in the rear surface of a post structure 18. This serves to position the post structure vertically and circumferentially relative to the file housing 10 and the disk spindle 12. while the surfaces on tool 20. from which the pins 32-1 and 32-2 protrude. serve to locate each post 18 radially from the true rotational axis of spindle 12.
  • the squareness or skew of the post l8 to a radial line from the rotational axis of spindle 12 is also established by setting the faces of the posts 18 against the surfaces on tool 20 from which the pins 32-] and 32-2protrude.
  • the post pivot bearings 36 are bolted to the cage at the threaded holes 40 while the outer races of these bearings are held loosely in split housings 35. Then the clamping screws in these housings are tightened to clamp the outer races of bearings 36 to the housings 35. With the outer races of post pivot bearings 36 clamped to the posts 18 and the inner races clamped to the cage 10. the post pivot axis will be fixed.
  • the post structures also incorporate stop brackets 44 containing spherical bearings 38, and the inner race of such bearing 38 is movable to engage a cage stop 42 which will determine at which radial location the post will be fixed during transducing operation. When the inner race contacts such cage stop 42.
  • a threaded screw is inserted within the inner race to hold the previously slidable bearing 38 in place. Thereafter. a screw is inserted to clat ip a split housing 44 that encompasses the stop bearing 38 so that the position of the bearing will be fixed. and will bear a permanent relation to the cage stop. This screw in the side of the split housing is per manently retained in position. so that whenever the post structure is pivoted away from the disk area and then returned for recording or playback modes. the inner race of bearing 38 will abut the cage stop at exactly the same position. ensuring that the post will be located having the same relation to the spindle axis as it previously had.
  • the post assembly 18 may now be unbolted from the hub tool 20. and the dowel pins 32 may be disengaged from the post dowel holes 34.
  • a second set of post structures 18 spaced 90 apart may be inserted in a similar manner. by releasing the pin 26 from aperture 300. and rotating the hub tool to engage the other aperture 30b with the pin 26.
  • four post structures circumferentially spaced apart are located with permanent radial. circumferential. height. and skew relationships relative to the true spindle axis.
  • the post structures 18 have dowels 46. and mounting holes 48 which cooperate with screws 49 attached to the racks. for accommodating rack supports 50 to which the head assemblies 16 are mounted.
  • the rack supports each carry two multielement head slider assemblies 16 which have been precisely positioned relative to the rectangular rack configuration and the rack surface.
  • the air bearing head assemblies. which are disclosed in the aforementioned U.S. Pat. No. 3.579.213 are aligned optically to reference surfaces of the rack.
  • the head assembly module is positioned on a rack platform 50 so that each transducing gap has a defined position relative to the datum surface of the rack.
  • Each head assembly 16 is formed to provide a number of transducing elements and sensing gaps. the gaps being aligned so that when the head assemblies are disposed adjacent to a disk surface.
  • each transducing element found on a rack support 50 is in'transducing relationship with a different data track.
  • the transducing elements on rack support 50 are serially aligned radially to the disk surface.
  • the elements of the racks supported by one post 18 at the front of the housing may be positioned over tracks that alternate with the tracks associated with the head elements mounted to the other front post. while the elements mounted to the two posts at the rear of the housing have the same relationship to each other. but serve to operate in parallel with transducing elements at the front of the file. over the same data tracks. to achieve faster access.
  • a multiplicity of racks 50 are mounted vertically onto the posts 18. by means of the dowels 46 and guide holes 48. and are fastened to the post assembly by screw means that pass through the guide holes 48.
  • the head racks 50 may be joined to the posts 18 before or after the posts are placed in the file housing l0. However. if the posts 18 have been first joined to the housing 10, then the post structures are released from the cage stops 42 to enable pivoting of the posts away from the disk area. to allow seating the head assembly racks in a vertical array along the length of the post.
  • any head rack 50 may he removed by loosening the post stop 40 from the cage stop 42. and swinging the post on the pivot formed by the bearing. away from the disk area. When the post is swung away from the disk area. all the head racks are available for individual servicing and replacement. Since the position of each rack is defined by the post hole and dowel arrangement. substitute rack assemblies will have exactly the same relationship to the post. and thus to the disks. as the rack assemblies which they replace. No special adjustments are requircd during the replacement process.
  • a circuit card 54 is coupled through connector plugs 56 and tongs 58 to the electrical windings of the head assemblies 16. as illustrated in FIGS. 6 and 7.
  • the card 54 carries electrical circuitry and components for processing signals to and from the magnetic heads 16.
  • a logic selection circuit 60 energizes selected ones of the transducer elements associated with the addressed data tracks. in accordance with signals received from an external control unit or processor.
  • the single common circuit card 54 thus is connected so that it may operate with a selected one of the transducing elements that is energized at any given time.
  • FIG. 9 Another feature of this invention is illustrated in FIG. 9, wherein the enclosed housing 10 containing the disk assembly 14 is coupled in a closed loop with a temperature control system 62. Air is exhausted from the disk area through exhaust tubes 64 and passed through the refrigeration and temperature control unit 62. where the temperature of the air is modified to maintain a substantially constant temperature. The processed air is then expelled by means of a blower 66 through tubings 68 through a filter 70 back into the disk area.
  • the exhaust paths 64 are closed. and the blower 66 is allowed to draw air in directly from the external environment from which it is passed through filter 70, blown through the disk area. and out the accessed opening of disk housing 10. in this way. a positive air pressure in the disk chamber. and a directed flow out of the area to prevent dust and other contamination from entering the head-disk chamber are maintained.
  • the inventive assembly also accommodates an air supply (not shown) that passes air through air vents 72 in the post structures to a bellows or diaphragm that provides a suspension or floating effect to the air hearing.
  • flying heads utilized in this embodiment.
  • the head assemblies may comprise single element transducers aligned on a rack. or multielement integral structures also aligned radially. or stepwise. for transducing operation. by way of example.
  • a fixerhead magnetic disk storage file comprising:
  • a drive spindle defining a rotational axis positioned in said housing
  • At least one pair of pivotable post structures positioned 180 apart. aligned parallel to and spaced equally from said spindle axis;
  • each head assembly having a like number of transducing elements that are aligned radially relative to a respective disk surface.
  • transducing elements of one post structure and those of the other post structure of said one pair being diametrically opposed and in transducing relation with the same data tracks to provide parallel data signal operation so that faster access is achieved;
  • said post structures being pivotable so that said head assemblies may be moved away and precisely back to the same positions such that said transducing elements are accurately aligned with the same data tracks as prior to rotation of the post structures.
  • a magnetic disk storage file as in claim I wherein two pairs of post structures are provided. each structure being spaced apart from the adjacent structures. and circumferentially around said spindle axis.
  • each disk surface coacts in transducing relation with at least four multi-head assemblies that are circumferentially and equally spaced about said axis.
  • each rack carrying a plurality of said head assemblies and transducing elements. said racks being fastened to said post structttres.
  • common circuit means is mounted to said post structures; and including a logic selection circuit coupled to said head assemblies. so that any ones of said transducing elements may be selected to be energized and form a closed circuit path in conjunction with said circuit means.
  • the combination further including refrigeration and filtration means. providing an air flow and cooling through thedisk area. thereby maintaining a clean air environment and a substantially constant temperature.
  • closed loop means coupled to said enclosure for eshausting air from the area of said disks:
  • temperature control means for maintaining the air within said enclosure at a substantially constant temperature.
  • said closed loop means providing a positive air flow outwardly from said enclosure to ambient air when said enclosure is opened. to prevent entry of contaminants.
  • ll. ln a magnetic disk storage file as in claim I. wherein said post structures include air vents providing access for air flow to said head assemblies. so that said head assemblies fly in relation to said rotary disks.
  • said hub tool being rotatable with saidspindle.

Landscapes

  • Moving Of Heads (AREA)
  • Automatic Disk Changers (AREA)
  • Supporting Of Heads In Record-Carrier Devices (AREA)
  • Holding Or Fastening Of Disk On Rotational Shaft (AREA)

Abstract

A magnetic disk storage file employs a plurality of magnetic transducers for each recording disk surface, and at least one transducer is associated with each data track. The transducer assemblies are supported by racks, which are mounted in stacked fashion to pivotable posts. The posts are fixed in a precise position relative to the true axis of the spindle on which the storage disks are mounted for rotation. The posts are pivotable so that the transducer assemblies and racks may be retracted for easy replacement, and returned to the same precise position and alignment relative to the data disk surface, whereby each transducer bears the same relation to its associated data track as it had prior to retraction.

Description

United States Patent 1 1 Hoehmann 1 1 MAGNETIC DISK STORAGE FILE [75] Inventor: Henry G. Hoehmann, Los Gatos,
Calif.
[73] Assignee: international Business Machines Corporation. Armonk. N.Y. [22] Filed: Mar. 18, 1970 (21] Appl. No.: 20,781
[521 US. Cl 360/98; 360/105 [51] 1nt.Cl ..G11c11/02 158] Field of Search... 340/174.1 C. 174.1 E. 74 M.
340/74 MD; 179/1002. 174.1 D
[56] References Cited UNITED STATES PATENTS 2.514.771 5/1978 Ehalt et a1 340/174.1 C 2.961.494 11/1960 Darow. Jr. et a1 179/1002 3.082.406 3/1963 Stevens 340/174.1 C 3.103.650 9/1963 Gehring.1r.et a1 340/1741 D 3,177.493 4/1965 Durlosky 340/l74.1 E 3.187.317 6/1965 Smith. Jr 340/174.1 C 3.320.599 5/1967 Billawala 340/1741 1 1 May 6, 197:
3.399.392 8/1968 Funazura 340/1741 3.478.341 11/1969 Trimble et a1. 340/1741 3.480.936 11/1969 Gerlach et a1. 340/1741 Primary Examiner-Benedict V. Safourek Attorney, Agent. or Firm--Nathan N. Kallman [57] ABSTRACT A magnetic disk storage file employs a plurality o: magnetic transducers for each recording disk surface and at least one transducer is associated with eacl data track. The transducer assemblies are supported by racks. which are mounted in stacked fashion tc pivotableposts. The posts are fixed in a precise posi tion relative to the true axis of the spindle on which the storage disks are mounted for rotation. The posts are pivotable so that the transducer assemblies and racks may be retracted for easy replacement. and returned to the same precise position and alignment relative to the data disk surface. whereby each transducer bears the same relation to its associated data track as it had prior to retraction.
12 Claims, 10 Drawing Figures MAGNETIC DISK STORAGE FILE gas. This arrangement was cumbersome and difficult t CROSS REFERENCE TO RELATED APPLlCATlON in us. Pat. No. 3.579.213 filed in bchalfof E. R. 80- SUMMARY OF THE NVENT'ON lyst. and assigned to the same assignee. a multigap mag- 5 An object of this invention is to provide a novel an netic head slider assembly is disclosed. which is particimpr d fix head. fixed disk ularly useful for fixed head files. The head assembly is Another ject Of this n ention is to provide a 'iXC an integral structure. having a plurality of transducing head disk fi erein two or more head transducin elements or flux-sensing nonmagnetic gaps. which are elements can be located over each data track and z uniformly spaced d li d fmscanning di lt) specific angular positions around the disk circumfei data tracks. In the apparatus of the instant application.
a number of such air bearing head assemblies are em- Anmhcl' j H lnvcmllm is Pmvldc a me pmycd i each i surface, head. fixed disk file wherein the individual magneu heads may be installed in a machine without position; BACKGROUND OF THE lNvli-N'liloN l5 adjustment at installation. to radial and circumferenti; Pick] f he rnvcmim positional accuracies greater than the sum of compt This invention relates to a novel magnetic disk storff y p age file. and in particular to a fixed head. fixed disk file. m pmvldc fixed l fixed dis wherein a number of magnetic head assemblies. each me wlfcrcm i l f dmks be f having a multiplicity oi" transducer elements. may he yet mummmmg Sim: f' f prucisuiy lncmcd mpctmvcly in he same posimm wk position of each transducer element to tts associate tive to recording media surl'aces. surmcc P f Descrimim Ur he prim A" Another UhjCLl ts to provide a support tor magnet:
head assemblies in a disk tile. whereby the write drive and read electronics may he commonly shared by set eral head assemblies.
A further object is to provide a fixed head t'ile conti uration which includes means for maintaining a "clca air environment within the machine. when in opera tion or when being serviced.
According to this invention. a fixed head. fixed dis file includes a plurality olspaced coasially aligne magnetic disks. and a plurality of head assemhlit mounted to racks. which in turn are supported h pivotablc post structures. The post structures allow th head assemblies to be simultaneously moved to pos tions adjacent to discrete record tracks on the disks; t be simultaneously pivoted away from the disks so th: certain head assemblies may be removed and rcplacct without displacement of the other heads or the disk liy the same token. the disks may be interchanged witl out affecting the head assemblies or their positions. I this tuanner. each head assembly and transducer Llt ment. or its replacement. will always hear the same Pt sition and attitude relative to its associated disk surl'ac and track.
Also. by means otthis invention. one common circu Presently known magnetic disk storage tiles employ a multiplicity ol magnetic disks. which cooperate with magnetic transducers or heads for recording and playback ol' data. The head assemblies may be of the accessing type. which are actuated radially relative to the disk surface to seek out selected tracks for recording 3 and retrieval ol'data. The random access actuator-type file may use one magnetic head assembly for each disk surface. which is an economical arrangement. but does not achieve the fast access capability that may be realized il'cach data track has a fixed transducer associated 35 therewith.
However. fixed head assemblies having transducing elements associated with each track of a disk storage file present a dil'ficulty when the head assemblies are being replaced. because each replacement head assem- 4t! hly must assume the same precise positional relationship relative to the disk surface and a data track. as existed before the exchange was made. It not. the new transducer elements and their sensing gaps may not be aligned properly relative to the associated disk surface 45 and data track. whereby data signal processing would be distorted and degraded. In prior art fixed head files.
ll mind he l card may be connected to a multiplicity of transduct relative to an associated track. and then individually ckmcms Sn hm during finding playback adjust the other head assemblies radially. while the 1 m f rh elements will be operative with disks were rotating and the head assemblies were opcrcircuit Anmhcr m i "w i -i f dug-c illlVL. ill UHlCY it! ilL'lIlLVL filtllill lflk'illltlll ilL'L'lll'ilLlL'S til yup i Inthy and ['Qfi'igcruti yn systg n flu nah LtLtltll inch or less. To make such at tt tains a clean air environment and substantially constat plicatcd and expensive mechanisms would be required. Mmwmmm i hi di m and the risk of damage caused by head disk intcrt'er- H cnce would exist when shifting loaded heads on rotatmulil' RWHUN DRAWN;
ing disks. It would be advantageous to have a simple. The invention will be described in greater detail wit inexpensive and convenient means for simultaneous reference to [he figures ol' the drawing in which:
and accurate adjustment and control of head position. m FIG. I is an isotnctric view. partly b k away. t.
pitch. roll. skew. and un aded height. particularly for picting part of an assembly of a fixed head. fixed di:
a plurality of flying heads in a fixed head tile. Also. it file in accordance with this invention;
is desirable that retnovnl of disks. when nece ary. FltlS. 2n and 2h are top uttd l'ront vlesrmrespectivel should not require the removal ol' the nondel'ective of a hub tool employed for positioning and aligning head assemblies in the storage t'ilc. M head mounting post structure. illustrated in the sit in prior known l'ixed head files. contamination con view of FIG. 2c;
trol in the disk head area was maintained by sealing the FIG. 3 is an isotnctric view of a post structure utililt entire area and prcssuri/ing the interior witlra clean in the novel assembly;
FIG. 4 is a rear plan view of a portion of the post structure;
FIG. 5 is a side elevation schematic view. partly broken away. illustrating the relation between the disk drive spindle. the support racks and mounted heads. and the pivotable post supporting such head racks;
HO. 6 is a schematic plan view. partly in block. depicting the head racks. electronic circuit card. and head selection circuitry;
FIG. 7 is an exploded view representing the relationship between the head racks and an associated disk. and the post and electronic curd structures. partially shown;
FIG. 8 is an enlarged isometric view of a head rack support; and
FIG. 9 is a schematic representation of the filtration and temperature control system utilized in this invention.
Similar numerals refer to similar elements throughout the drawing.
DESCRIPTION OF THE PREFERRED EMBODIMENT With reference to FIG. 1. a magnetic disk storage file structure is illustrated. including a substantially square housing or cage 10. in which a drive shaft or spindle i2 is centrally located. When the file is in operation. a stack of spaced magnetic disks 14 (see FIGS. 5, 9) or a disk pack is mounted to the spindle l2. and rotated relative to magnetic transducers 16 for recording or playback of data. In this particular embodiment. the transducers or head assemblies 16 are fixed (in rack supports 50) relative to the disk surfaces during operation of the storage file. so that each data track has one associated transducer. or more. cooperating therewith. in a fixed head file type. one or more of the rack supports 50 or disks may be removed conveniently for re placement purposes. as a result of wear or defects.
it should be appreciated that in high density data systems wherein the data bits are closely packed along a data track. and the data tracks are closely spaced along the radial direction ofthe disk surface. if more than one transducing element is located on each track to minimize waiting time before reading the desired information; and it is required to read two or more tracks simultaneously. the need for accurate radial and circumferential alignment of each transducing element relative to the other transducing elements is critical.
To this end. post structures l8 (shown enlarged and in greater detail in FIG. 3) that support the head assemblies are positioned precisely at predetermined locations relative to the spindle 12. to which the storage disks l4 are coaxially mounted. To accomplish this precise positioning. a hub tool 20 (see FIGS. 2a. b) is seated to a flange 22 of the spindle l2. centered to the spindle by a collar formed in a recess at the top of the spindle. and fastened to the spindle by bolting. for example. A fixture 24. having a depressihle spring-loaded pin 26. is positioned in a keyed recess 28 in the top surface of the housing l0. and the hub tool 20 and rotary spindle 12 are manually rotated. until the pin 26 engages an aperture 30a or 30b in the hub tool periphery. At this time. the hub tool is locked in a stationary indexed position. if positioned by locking the pin 26 in aperture 300. the hub tool will serve to locate and align two post structures at the rear corners of the cage and on the other hand. ifaperture 30b is engaged by the pin 26. two post structures at the front corners of the cage may be located and aligned.
With the hub tool so positioned and locked. a set of vertically spaced dowel pins 32-1 for one post position (or 32-2 for another post position. preferably displaced 90). that project from the hub tool. are meshed with vertically spaced guide holes 34 (only the upper one being shown in FIG. 4) formed in the rear surface of a post structure 18. This serves to position the post structure vertically and circumferentially relative to the file housing 10 and the disk spindle 12. while the surfaces on tool 20. from which the pins 32-1 and 32-2 protrude. serve to locate each post 18 radially from the true rotational axis of spindle 12. The squareness or skew of the post l8 to a radial line from the rotational axis of spindle 12 is also established by setting the faces of the posts 18 against the surfaces on tool 20 from which the pins 32-] and 32-2protrude.
With a post 18 so located and fastened to the hub tool 20. the post pivot bearings 36 are bolted to the cage at the threaded holes 40 while the outer races of these bearings are held loosely in split housings 35. Then the clamping screws in these housings are tightened to clamp the outer races of bearings 36 to the housings 35. With the outer races of post pivot bearings 36 clamped to the posts 18 and the inner races clamped to the cage 10. the post pivot axis will be fixed. The post structures also incorporate stop brackets 44 containing spherical bearings 38, and the inner race of such bearing 38 is movable to engage a cage stop 42 which will determine at which radial location the post will be fixed during transducing operation. When the inner race contacts such cage stop 42. a threaded screw is inserted within the inner race to hold the previously slidable bearing 38 in place. Thereafter. a screw is inserted to clat ip a split housing 44 that encompasses the stop bearing 38 so that the position of the bearing will be fixed. and will bear a permanent relation to the cage stop. This screw in the side of the split housing is per manently retained in position. so that whenever the post structure is pivoted away from the disk area and then returned for recording or playback modes. the inner race of bearing 38 will abut the cage stop at exactly the same position. ensuring that the post will be located having the same relation to the spindle axis as it previously had. The post assembly 18 may now be unbolted from the hub tool 20. and the dowel pins 32 may be disengaged from the post dowel holes 34.
A second set of post structures 18 spaced 90 apart may be inserted in a similar manner. by releasing the pin 26 from aperture 300. and rotating the hub tool to engage the other aperture 30b with the pin 26. Thus. four post structures circumferentially spaced apart are located with permanent radial. circumferential. height. and skew relationships relative to the true spindle axis.
As illustrated in FIG. 4, the post structures 18 have dowels 46. and mounting holes 48 which cooperate with screws 49 attached to the racks. for accommodating rack supports 50 to which the head assemblies 16 are mounted. in this particular embodiment. the rack supports each carry two multielement head slider assemblies 16 which have been precisely positioned relative to the rectangular rack configuration and the rack surface. The air bearing head assemblies. which are disclosed in the aforementioned U.S. Pat. No. 3.579.213 are aligned optically to reference surfaces of the rack.
and are adjusted for unloaded height. skew. pitch. roll. and track adjustments of screws 52'(see FIG. 8) in a manner known to those skilled in the art. The head assembly module is positioned on a rack platform 50 so that each transducing gap has a defined position relative to the datum surface of the rack.
Each head assembly 16 is formed to provide a number of transducing elements and sensing gaps. the gaps being aligned so that when the head assemblies are disposed adjacent to a disk surface. each transducing element found on a rack support 50 is in'transducing relationship with a different data track. In effect. the transducing elements on rack support 50 are serially aligned radially to the disk surface. in one preferred embodiment. the elements of the racks supported by one post 18 at the front of the housing may be positioned over tracks that alternate with the tracks associated with the head elements mounted to the other front post. while the elements mounted to the two posts at the rear of the housing have the same relationship to each other. but serve to operate in parallel with transducing elements at the front of the file. over the same data tracks. to achieve faster access.
A multiplicity of racks 50 are mounted vertically onto the posts 18. by means of the dowels 46 and guide holes 48. and are fastened to the post assembly by screw means that pass through the guide holes 48. it should be noted that the head racks 50 may be joined to the posts 18 before or after the posts are placed in the file housing l0. However. if the posts 18 have been first joined to the housing 10, then the post structures are released from the cage stops 42 to enable pivoting of the posts away from the disk area. to allow seating the head assembly racks in a vertical array along the length of the post.
Similarly. for maintenance and service. any head rack 50 may he removed by loosening the post stop 40 from the cage stop 42. and swinging the post on the pivot formed by the bearing. away from the disk area. When the post is swung away from the disk area. all the head racks are available for individual servicing and replacement. Since the position of each rack is defined by the post hole and dowel arrangement. substitute rack assemblies will have exactly the same relationship to the post. and thus to the disks. as the rack assemblies which they replace. No special adjustments are requircd during the replacement process.
Once the post structures 18 are properly positioned in the housing 10. the posts are detached from the cage stops 42 and pivoted on the bearings 36 away from the disk area. The hub tool is then released from the spindle l2 and disks 14 are mounted to the spindle in a manner described in U.S. Pat. No. 3.587.073 filed in behalf of S. Ghose et al. and assigned to the same assignce as the present invention.
With the head racks 50 mounted to the posts [8. a circuit card 54 is coupled through connector plugs 56 and tongs 58 to the electrical windings of the head assemblies 16. as illustrated in FIGS. 6 and 7. The card 54 carries electrical circuitry and components for processing signals to and from the magnetic heads 16. A logic selection circuit 60 energizes selected ones of the transducer elements associated with the addressed data tracks. in accordance with signals received from an external control unit or processor. The single common circuit card 54 thus is connected so that it may operate with a selected one of the transducing elements that is energized at any given time.
Another feature of this invention is illustrated in FIG. 9, wherein the enclosed housing 10 containing the disk assembly 14 is coupled in a closed loop with a temperature control system 62. Air is exhausted from the disk area through exhaust tubes 64 and passed through the refrigeration and temperature control unit 62. where the temperature of the air is modified to maintain a substantially constant temperature. The processed air is then expelled by means of a blower 66 through tubings 68 through a filter 70 back into the disk area. When the disk housing 10 is opened for service. the exhaust paths 64 are closed. and the blower 66 is allowed to draw air in directly from the external environment from which it is passed through filter 70, blown through the disk area. and out the accessed opening of disk housing 10. in this way. a positive air pressure in the disk chamber. and a directed flow out of the area to prevent dust and other contamination from entering the head-disk chamber are maintained.
The inventive assembly also accommodates an air supply (not shown) that passes air through air vents 72 in the post structures to a bellows or diaphragm that provides a suspension or floating effect to the air hearing. flying heads utilized in this embodiment.
it should be understood that the specific embodiment disclosed herein may be modified and varied within the scope of the invention. For example. other than four post structures may be used. Hinge pins or swivel posts may be employed in lieu of spherical pivot bearings. The head assemblies may comprise single element transducers aligned on a rack. or multielement integral structures also aligned radially. or stepwise. for transducing operation. by way of example.
What is claimed is:
l. A fixerhead magnetic disk storage file comprising:
a housing;
a drive spindle defining a rotational axis positioned in said housing;
a plurality of magnetic disks mounted coaxially on said spindle. said disks having recording surfaces on which data tracks are formed;
at least one pair of pivotable post structures positioned 180 apart. aligned parallel to and spaced equally from said spindle axis;
a multiplicity of multi-element head assemblies mounted to said post structures. each head assembly having a like number of transducing elements that are aligned radially relative to a respective disk surface. when the post structure is fixed for file operation and data signal transducing;
the transducing elements of one post structure and those of the other post structure of said one pair being diametrically opposed and in transducing relation with the same data tracks to provide parallel data signal operation so that faster access is achieved;
said post structures being pivotable so that said head assemblies may be moved away and precisely back to the same positions such that said transducing elements are accurately aligned with the same data tracks as prior to rotation of the post structures.
2. A magnetic disk storage file as in claim I, wherein two pairs of post structures are provided. each structure being spaced apart from the adjacent structures. and circumferentially around said spindle axis.
and a like number of rnulti-element head assemblies mounted to each post structure. so that each disk surface coacts in transducing relation with at least four multi-head assemblies that are circumferentially and equally spaced about said axis.
3. A magnetic disk storage tile as in claim 2. wherein the transducing elements mounted to one post structure are positioned over one set of data tracks and the transducing elements mounted to adjacent post structures are positioned over alternate interleaved data tracks.
4. In a magnetic disk storage tile as in claim 1. wherein said head assemblies are aligned in columns over said tracks. substantially parallel to the axis of said drive spindle.
5. In a magnetic disk storage file as in claim I. further including a number of racks. each rack carrying a plurality of said head assemblies and transducing elements. said racks being fastened to said post structttres.
6. in a magnetic disk storage tile as in claim I. including a pivot bearing assembly coupled to said housing and to said post structures. providing a pivot for said post structures.
7. In a magnetic disk storage file as in claim l. further including common circuit means. and electrical conncctor means coupled to said multiplicity of magnetic head assemblies. said connector means coupling all of said head assemblies to said circuit means. so that selected ones of said transducing elements may be operative with said common circuit means at a given time.
8. In a magneticdisk storage tile as in claim 7.
wherein said common circuit means is mounted to said post structures; and including a logic selection circuit coupled to said head assemblies. so that any ones of said transducing elements may be selected to be energized and form a closed circuit path in conjunction with said circuit means.
9. In a magnetic disk storage tile as in claim t. the combination further including refrigeration and filtration means. providing an air flow and cooling through thedisk area. thereby maintaining a clean air environment and a substantially constant temperature.
[0. ln a magnetic disk storage tile as in claim 9. further including an enclosure for said file. said disks and head assemblies being disposed within said enclosure:
closed loop means coupled to said enclosure for eshausting air from the area of said disks: and
temperature control means for maintaining the air within said enclosure at a substantially constant temperature. said closed loop means providing a positive air flow outwardly from said enclosure to ambient air when said enclosure is opened. to prevent entry of contaminants. I
ll. ln a magnetic disk storage file as in claim I. wherein said post structures include air vents providing access for air flow to said head assemblies. so that said head assemblies fly in relation to said rotary disks.
[2. lo a magnetic disk storage file as in claim I. including a hub tool providing alignment means for said post structures relative to the axis of said drive spindle.
said hub tool being rotatable with saidspindle.
Q C I Q i

Claims (12)

1. A fixed head magnetic disk storage file comprising: a housing; a drive spindle defining a rotational axis positioned in said housing; a plurality of magnetic disks mounted coaxially on said spindle, said disks having recording surfaces on which data tracks are formed; at least one pair of pivotable post structures positioned 180* apart, aligned parallel to and spaced equally from said spindle axis; a multiplicity of multi-element head assemblies mounted to said post structures, each head assembly having a like number of transducing elements that are aligned radially relative to a respective disk surface, when the post structure is fixed for file operation and data signal transducing; the transducing elements of one post structure and those of the other post structure of said one pair being diametrically opposed and in transducing relation with the same data tracks to provide parallel data signal operation so that faster access is achieved; said post structures being pivotable so that said head assemblies may be moved away and precisely back to the same positions such that said transducing elements are accurately aligned with the same data tracks as prior to rotation of the post structures.
2. A magnetic disk storage file as in claim 1, wherein two pairs of post structures are provided, each structure being spaced 90* apart from the adjacent structures, and circumferentially around said spindle axis, and a like number of multi-element head assemblies mounted to each post structure, so that each disk surface coacts in transducing relation with at least four multi-head assemblies that are circumferentially and equally spaced about said axis.
3. A magnetic disk storage file as in claim 2, wherein the transducing elements mounted to one post structure are positioned over one set of data tracks and the transducing elements mounted to adjacent post structures are positioned over alternate interleaved data tracks.
4. In a magnetic disk storage file as in claim 1, wherein said head assemblies are aligned in columns over said tracks, substantially parallel to the axis of said drive spindle.
5. In a magnetic disk storage file as in claim 1, further including a number of racks, each rack carrying a plurality of said head assemblies and transducing elements, said racks being fastened to said post structures.
6. In a magnetic disk storage file as in claim 1, including a pivot bearing assembly coupled to said housing and to said post structures, providing a pivot for said post structures.
7. In a magnetic disk storage file as in claim 1, further including common circuit means, and electrical connector means coupled to said multiplicity of magnetic head assemblies, said connector means coupling all of said head assemblies to said circuit means, so that selected ones of said transducing elements may be operative with said common circuit means at a given time.
8. In a magnetic disk storage file as in claim 7, wherein said common circuit means is mounted to said post structures; and including a logic selection circuit coupled to said head assemblies, so that any ones of said transducing elements may be selected to be energized and form a closed circuit path in conjunction with said circuit means.
9. In a magnetic disk storage file as in claim 1, the combination further including refrigeration and filtration means, providing an air flow and cooling through the disk area, thereby maintaining a clean air environment and a substantially constant temperature.
10. In a magnetic disk storage file as in claim 9, further including an enclosure for said file, said disks and head assemblies being dIsposed within said enclosure; closed loop means coupled to said enclosure for exhausting air from the area of said disks; and temperature control means for maintaining the air within said enclosure at a substantially constant temperature, said closed loop means providing a positive air flow outwardly from said enclosure to ambient air when said enclosure is opened, to prevent entry of contaminants.
11. In a magnetic disk storage file as in claim 1, wherein said post structures include air vents providing access for air flow to said head assemblies, so that said head assemblies fly in relation to said rotary disks.
12. In a magnetic disk storage file as in claim 1, including a hub tool providing alignment means for said post structures relative to the axis of said drive spindle, said hub tool being rotatable with said spindle.
US020781A 1970-03-18 1970-03-18 Magnetic disk storage file Expired - Lifetime US3882473A (en)

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Application Number Priority Date Filing Date Title
US020781A US3882473A (en) 1970-03-18 1970-03-18 Magnetic disk storage file
JP46001641A JPS5113565B1 (en) 1970-03-18 1971-01-22
FR7106541A FR2083973A5 (en) 1970-03-18 1971-02-16
BE763146A BE763146A (en) 1970-03-18 1971-02-18 MAGNETIC DISC MEMORY
CA106,852,A CA950580A (en) 1970-03-18 1971-03-04 Magnetic disk storage file
DE2112156A DE2112156C3 (en) 1970-03-18 1971-03-13 Magnetic disk storage with stationary magnetic heads
GB2053671A GB1331818A (en) 1970-03-18 1971-04-19 Magnetic disc file

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US3882473A true US3882473A (en) 1975-05-06

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JP (1) JPS5113565B1 (en)
BE (1) BE763146A (en)
CA (1) CA950580A (en)
DE (1) DE2112156C3 (en)
FR (1) FR2083973A5 (en)
GB (1) GB1331818A (en)

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US4008492A (en) * 1975-07-23 1977-02-15 Control Data Corporation Thermally stabilized enclosure for magnetic disk
US4280155A (en) * 1979-06-04 1981-07-21 Memorex Mini Disc Drive Corp. Method of improving air flow in compact disc drive
US4381528A (en) * 1976-09-24 1983-04-26 Tokyo Shibaura Electric Co., Ltd. Enclosed-type magnetic disc recording and/or reproducing apparatus
US4396964A (en) * 1980-07-02 1983-08-02 Storage Technology Corporation Recirculating air system for magnetic disk drive
US6317286B1 (en) 1999-01-29 2001-11-13 Seagate Technology Llc Diaphragm-sealed disc drive
US6373648B2 (en) * 1998-04-27 2002-04-16 Intel Corporation Disk head assembly with multiple read and/or write transducers for improved performance
US6785089B2 (en) 2001-11-13 2004-08-31 Seagate Technology Llc Disc drive gas supply system
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US4008492A (en) * 1975-07-23 1977-02-15 Control Data Corporation Thermally stabilized enclosure for magnetic disk
US4381528A (en) * 1976-09-24 1983-04-26 Tokyo Shibaura Electric Co., Ltd. Enclosed-type magnetic disc recording and/or reproducing apparatus
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US6785089B2 (en) 2001-11-13 2004-08-31 Seagate Technology Llc Disc drive gas supply system
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Also Published As

Publication number Publication date
BE763146A (en) 1971-07-16
DE2112156C3 (en) 1978-10-19
FR2083973A5 (en) 1971-12-17
DE2112156B2 (en) 1978-03-02
CA950580A (en) 1974-07-02
GB1331818A (en) 1973-09-26
DE2112156A1 (en) 1971-10-07
JPS5113565B1 (en) 1976-04-30

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