Arrangement for positioning a recording disc of a disc cartridge

Claim 2

A disc cartridge comprising; a cartridge case; a recording disc assembly rotatably accommodated in said cartridge case; said recording disc assembly comprising recording disc, a contacting surface for detachably contacting with a reference surface of a disc drive device and a disc supporting plate having a disc securing surface to which an inner peripheral edge of the recording disc is secured thereby supporting the recording disc, said contacting surface and securing surface being situated on the same surface of the disc supporting plate.

Claim 3

The disc cartridge according to claim 1, wherein said disc supporting plate is made of a metal plate.

Claim 4

The disc cartridge according to claim 2, wherein said disc supporting plate is made of a magnetic metal plate.

Claim 5

The disc cartridge according to claim 1, wherein said disc supporting plate has a round plate having said contacting surface at the central portion and said securing surface on the outer peripheral edge portion of the round plate.

Claim 6

The disc cartridge according to claim 4, wherein said disc supporting plate is made of a flat magnetic metal plate.

Claim 7

The disc cartridge according to claim 1, wherein said recording disc assembly further comprises rib means disposed on the contacting surface for contacting an inner wall defining a drive member insertion opening of the cartridge case, whereby the recording disc is secured to the disc supporting plate by fitting the central hole of the recording disc with the rib means.

Claim 8

In a disc cartridge comprising; a cartridge case; a recording disc assembly rotatably accommodated in said cartridge case; said recording disc assembly comprising recording disc, a contacting surface for detachably contacting with a reference surface of a disc drive device and a disc supporting plate having disc securing surface to which an inner peripheral edge of the recording disc is secured thereby supporting the recording disc, and rib means disposed on the supporting plate for regulating the position of the recording disc assembly in a radial direction, said rib means being provided with a pair of flat walls arranged in a V character shape in plan view for abutting to a part of the cylindrical surface of the disc drive shaft of the disc drive device for positioning the center of the disc assembly when the disc assembly is rotated.

Claim 9

In a disc cartridge comprising; a cartridge case; a recording disc assembly rotatably accommodated in said cartridge case; said recording disc assembly comprising recording disc, a contacting surface for detachably contacting with a reference surface of a disc drive device and a disc supporting plate having disc securing surface to which an inner peripheral edge of the recording disc is secured thereby supporting the recording disc, and rib means disposed on the supporting plate for regulating the position of the recording disc assembly in a radial direction, said rib means being provided with a pair of flat walls arranged in a V character shape in plan view for abutting to a part of the cylindrical surface of the disc drive shaft of the disc drive device for positioning the center of the disc assembly when the disc assembly is rotated.

Claim 10

The disc cartridge according to claim 7, wherein said disc assembly comprises engaging means disposed in the inner portion surrounded by the rib means for engaging with a drive pin provided in the disc drive device to rotate the disc assembly.

Claim 11

The disc cartridge according to claim 8, wherein said disc supporting plate is made of a magnetic metal plate.

Claim 12

The disc cartridge according to claim 8, wherein at least any one side of the top case and disc assembly comprises a projection acting as a spacer for defining a space between the drive pin and the inner surface of the cartridge case.

Claim 13

The disc cartridge according to claim 10, wherein said projection is formed at the central portion of the disc supporting plate.

Claim 14

A disc drive device comprising; disc receiving means formed on the end portion of the spindle, the top face of the disc receiving means serving as a reference surface for defining the position of the recording disc in a thickness direction of the disc, and the outer surface of the disc receiving means serving as a reference surface of the recording disc in the radial direction of the recording disc.

Claim 15

A disc drive device comprising; disc receiving means formed on the end portion of the spindle, the top face of the disc receiving means serving as a reference surface for defining the position of the recording disc in a thickness direction of the disc, and the outer surface of the disc receiving means serving as a reference surface of the recording disc in the radial direction of the recording disc.

Claim 16

The disc drive device according to claim 12, wherein a permanent magnet is disposed in an inner portion of the disc receiving means.

Claim 17

The disc drive device according to claim 12, wherein said disc receiving means is movably provided with a drive pin at the center portion of the disc receiving means.