EP0087300A2
Expired / Lapsed
EP
⏱️ 0.0 years remaining
Rotary head-positioning actuator for a disc data store
Assignee: Unisys Corp
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Filing: 1983-02-21
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Granted: —
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Expires: 2003-02-21
Abstract
Abstract A rotary actuator is provided for use as part of a servomechanism for positioning one or more data recording and/or recovering heads over selectable radii on one or more rotating data storage discs, the actuator 10 comprising a head arm 24 pivoted to rotate with a shaft 20 held between bearings 18 32 in a yoke 12, the actuator 10 being characterised by one of the bearings 18 being a composite bearing allowing both axial and rotational movement of the shaft 20 without play and by the other bearing 32 being a rotary bearing, the two bearings 18,32, co-operating to fix the axial position of the shaft 20 whilst allowing free rotation and axial movement due to dimensional changes whenever the axial force exceeds a predetermined limit, thereby avoiding rotary bearing binding or undue play attendant upon prior art designs.
Inventors
- 👤 Charles William Donkin
Bibliographic Details
Application Number
—
Jurisdiction
EP
Data Source
google_patents
Last Synchronized
2026-10-30 00:39
CPC Classifications
F; F16; F16C; F16C31/00; F16C31/04; G; G11; G11B; G11B21/00; G11B21/02; G11B21/08; G11B5/00; G11B5/48; G11B5/54; G11B5/55; G11B5/5521
Claims Analysis
Total Claims: 15
Claim 1
Independent Claim
151 words
An apparatus for mounting a shaft for the support of a head-positioning actuator in a disc data store for the rotation of said shaft about an axis and for the location of said shaft in the direction of said axis, said apparatus comprising; a first rotary bearing at a first location on said shaft for allowing the rotation of said shaft about said axis and for attaching said shaft to a first location on a .support member and a composite bearing, said composite bearing comprising a second rotary bearing at a second location on said shaft for allowing said shaft to rotate about said axis and an axial roller bearing at a second location on said support member for the support of said second rotary bearing, where said axial bearing is operable to allow said second rotary bearing to move within a predetermined range whenever a predetermined axial force is exceeded.
Claim 2
Independent Claim
151 words
An apparatus for mounting a shaft for the support of a head-positioning actuator in a disc data store for the rotation of said shaft about an axis and for the location of said shaft in the direction of said axis, said apparatus comprising; a first rotary bearing at a first location on said shaft for allowing the rotation of said shaft about said axis and for attaching said shaft to a first location on a .support member and a composite bearing, said composite bearing comprising a second rotary bearing at a second location on said shaft for allowing said shaft to rotate about said axis and an axial roller bearing at a second location on said support member for the support of said second rotary bearing, where said axial bearing is operable to allow said second rotary bearing to move within a predetermined range whenever a predetermined axial force is exceeded.
Claim 3
Dependent Claim
67 words
An apparatus according to claim 1 wherein said axial bearing comprises; an outer axial ring for engaging said second location on said support member, an inner axial ring for engaging said second rotary bearing, and a plurality of balls disposed intermediately between said outer axial ring and said inner axial ring, said balls being elastic and compressed therebetween by a predetermined amount to provide said predetermined force.
Claim 4
Dependent Claim
103 words
An apparatus according to claim 2 wherein said outer axial ring comprises a plurality of axially-extensive outer recesses on the face thereof intermediate between said inner and said outer axial rings, wherein said inner axial ring comprises a corresponding plurality of axially-extensive inner recesses on the face thereof intermediate between said inner and said outer rings, and wherein said plurality of balls are held between pairs of said inner and said outer recesses for the allowing of mutual axial movement between said inner and said outer axial rings but the prevention of mutual rotational movement between said inner and said outer axial rings.
Claim 5
Independent Claim
94 words
An apparatus according to claim 2_or 3 wherein said outer axial ring comprises a first outer axial stop at a first axial end of said axial bearing, wherein said inner axial ring comprises a first inner axial stop at a first axial end of said axial bearing, and wherein said first outer axial stop and said first inner axial stop are adapted to co-operate to trap at least one out of said plurality of balls therebetween to limit further axial movement whenever the limit of said predetermined range is reached in a first direction.
Claim 6
Dependent Claim
43 words
An apparatus according to claim 4 wherein said first outer axial stop comprises a first outer axial lip extensive towards said inner axial ring and wherein said first inner axial stop comprises a first inner axial lip extensive towards said outer axial ring.
Claim 7
Dependent Claim
43 words
An apparatus according to claim 5 wherein said first outer axial lip comprises a first elastically expansive clip held by said outer axial ring and wherein said first inner axial lip comprises a first elastically contractile clip held by said inner axial ring.
Claim 8
Dependent Claim
56 words
An apparatus according to claim 4 when dependent upon claim 3 wherein said first outer axial stop is an end wall in at least one out of said plurality of outer recesses and wherein said first inner axial stop is an end wall in at least a matching one out of said plurality of inner recesses.
Claim 9
Dependent Claim
97 words
An apparatus according to claim 4, 5, 6 or 7 wherein said outer axial ring comprises a second outer axial stop at said second axial end of said axial bearing, wherein said inner axial ring comprises a second inner axial stop at said first axial end of said axial bearing, and wherein said second outer axial stop and said second inner axial stop are adapted to co-operate to trap at least one out of said plurality of balls therebetween to limit further axial movement whenever the limit of said predetermined range is reached in a second direction.
Claim 10
Dependent Claim
43 words
An apparatus according to claim 8 wherein said second outer axial stop comprises a second outer axial lip extensive towards said inner axial ring and wherein said second inner axial stop comprises a second inner axial lip extensive towards said outer axial ring.
Claim 11
Dependent Claim
43 words
An apparatus according to claim 9 wherein said second outer axial lip comprises a second elastically expansive clip held by said outer axial ring and wherein said second inner axial lip comprises a second elastically contractile clip held by said inner axial ring.
Claim 12
Dependent Claim
64 words
11 . An apparatus according to claims 3, 4, 5 or 6 and according to claims 8, 9 or 10 when dependent upon claims 4, 5 or 6 , wherein said inner axial recesses are extensive throughout the entire axial extent of said outer axial ring and wherein said outer axial recesses are extensive throughout the entire axial extent of said inner axial ring.
Claim 13
Dependent Claim
33 words
1 2. An apparatus according to claims 2 to 11 wherein said second rotary bearing comprises an outer rotary ring and wherein said inner axial ring is supportive of said outer rotary ring.
Claim 14
Dependent Claim
18 words
An apparatus according to claim 12 wherein said outer rotary ring is integral with said inner axial ring.
Claim 15
Independent Claim
63 words
An apparatus according to any of the preceding claims wherein said support member is a yoke comprising first and second opposed faces, wherein said first location on said support member is on said first face, wherein said second location,on said support member is on said second face, and wherein said shaft is penetrative, at least in part, of said first and second faces.
References Cited (Backward Citations)
No citation records indexed.
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