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EP0095800A1 Expired / Lapsed EP ⏱️ 0.0 years remaining

Optical-disc apparatus

Assignee: Koninklijke Philips NV
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Filing: 1983-05-17
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Granted: —
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Expires: 2003-05-17
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Abstract

Abstract The invention relates to optical-disk apparatus for playing back and/or recording information on rotary optical discs (7), which apparatus comprises a clamping device which clamps an optical disc on a spindle (14). The clamping device comprises a disc loader (21) which moves with clearance in a support (2) which moves between the rest position and an operating position, which disc loader clamps the disc magnetically onto the spindle by means of permanent-magnetic means. To prevent the disc loader rattling or taking up an oblique position in the support when the support is not in its operating position, the permanent-magnetic means comprise means (35A, B) which exert a magnetic force which acts between the support and the disc loader so that the disc loader is clamped against the support when the latter is not in the operating position.

Inventors

  • 👤 Eduard Camerik

Bibliographic Details

Application Number —
Jurisdiction EP
Data Source google_patents
Last Synchronized 2026-11-08 05:36
CPC Classifications
G; G11; G11B; G11B17/00; G11B17/02; G11B17/022; G11B17/028; G11B17/0284

Claims Analysis

Total Claims: 5
Claim 1
Independent Claim 330 words
An optical-disc apparatus for playing back and/or recording information on a rotary optical disc (7), which apparatus comprises: - a spindle (14) with a free end (15), which spindle is rotatable about an axis of rotation (13), and - a clamping device for clamping an optical disc onto the spindle (14), which device comprises: - a disc loader (21) comprising a thrust portion (32) on a first side, which thrust portion, during operation, exerts pressure on an optical disc placed on the spindle and thereby presses said disc against the spindle, a second portion (33) on a second side, and a central portion (34) between the first and second sides, which central portion has a maximum transverse dimension which is smaller than that of the thrust portion and that of the second portion, - permanent-magnetic means (35A, B) for magnetically urging the disc loader against the disc during operation, and - a support (3) for the disc loader (21), which support is movable between a rest position and an operating position and has an opening (36) through which the central portion (34) of the disc loader extends with clearance and which opening has a maximum transverse dimension which is smaller than that of the second portion (33) of the disc loader, and which support allows the disc loader ro rotate freely with a disc when said snpport is in the operating position, carries the disc loader when said support is in the rest position, and co-operates with the second portion (33) of the disc loader (21) to move said disc loader away from the optical disc and thereby release the clamping of the disc on the spindle when the support is moved from the operating position to the rest position, characterized in that said permanent-magnetic means comprise means (35A, B) which exert a magnetic force which acts between the support and the disc loader and which magnetically clamp the disc loader against the support in the rest position (Figures 1-6).
Claim 2
Dependent Claim 330 words
An optical-disc apparatus for playing back and/or recording information on a rotary optical disc (7), which apparatus comprises: - a spindle (14) with a free end (15), which spindle is rotatable about an axis of rotation (13), and - a clamping device for clamping an optical disc onto the spindle (14), which device comprises: - a disc loader (21) comprising a thrust portion (32) on a first side, which thrust portion, during operation, exerts pressure on an optical disc placed on the spindle and thereby presses said disc against the spindle, a second portion (33) on a second side, and a central portion (34) between the first and second sides, which central portion has a maximum transverse dimension which is smaller than that of the thrust portion and that of the second portion, - permanent-magnetic means (35A, B) for magnetically urging the disc loader against the disc during operation, and - a support (3) for the disc loader (21), which support is movable between a rest position and an operating position and has an opening (36) through which the central portion (34) of the disc loader extends with clearance and which opening has a maximum transverse dimension which is smaller than that of the second portion (33) of the disc loader, and which support allows the disc loader ro rotate freely with a disc when said snpport is in the operating position, carries the disc loader when said support is in the rest position, and co-operates with the second portion (33) of the disc loader (21) to move said disc loader away from the optical disc and thereby release the clamping of the disc on the spindle when the support is moved from the operating position to the rest position, characterized in that said permanent-magnetic means comprise means (35A, B) which exert a magnetic force which acts between the support and the disc loader and which magnetically clamp the disc loader against the support in the rest position (Figures 1-6).
Claim 3
Dependent Claim 36 words
An optical-disc apparatus as claimed in Claim 1, characterized in that the magnetic means (735) comprise means which exert a magnetic tensile force which acts between the support (73) and the disc loader (721). (Figure 7).
Claim 4
Dependent Claim 101 words
An optical-disc apparatus as claimed in Claim 3, characterized in that - the second portion (733) of the disc loader comprises a ferro-magnetic ring, - the permanent-magnetic means (735) comprise an axially magnetized annular permanent magnet (735) which is mounted rigidly on the support (73) and which is arranged concentrically with the central portion (734) of the disc loader (721), and - in the operating position of the support (73), when an optical disc (7) has been placed on the spindle (14), a narrow axial air gap is formed between said annular magnet (735) and said ferro-magnetic ring (733). (Figure 7).
Claim 5
Dependent Claim 45 words
An optical-disc apparatus as claimed in any of Claims 1 to 3, characterized in that the permanent-magnetic means (835A,B) also comprise, in known manner, means (835B) for exerting a magnetic tensile force which acts between the spindle (14) and the disc loader (821). (Figure 8).

References Cited (Backward Citations)

US4232870A Cited
GB2023768A Cited
DE2909099A1 Cited
EP0070557A1 Cited

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