A disk drive assembly including a spindle motor including a hub and a central axis, at least one disk disk having a central opening positioned on the hub and concentric about the central axis, an annular ring member concentric about the central axis, wherein a first portion of the annular ring member is in contact with an outer surface of a top disk of the disk stack, and a disk clamp ring screw adjacent to and in contact with a second portion of the annular ring member, wherein the disk clamp ring screw provides a clamping force to at least partially compress the annular ring member toward the top disk of the disk stack.

A disk drive assembly including a spindle motor including a hub and a central axis, at least one disk disk having a central opening positioned on the hub and concentric about the central axis, an annular ring member concentric about the central axis, wherein a first portion of the annular ring member is in contact with an outer surface of a top disk of the disk stack, and a disk clamp ring screw adjacent to and in contact with a second portion of the annular ring member, wherein the disk clamp ring screw provides a clamping force to at least partially compress the annular ring member toward the top disk of the disk stack.

An operating method of a disc pick-and-place device is provided. Discs can be picked up when each flexible rod is driven to rotate and make the disc pick-and-place device enter a first operating state and then a second operating state in which the first carrying portion is located at the disc releasing position and then at the disc holding position, and the second carrying portion is located at the disc releasing position in the first and second operating states. Discs can be unloaded when each flexible rod is driven to rotate and make the disc pick-and-place device enter a third operating state and then a fourth operating state in which the first carrying portion is located at the disc holding position and then at the disc releasing position, and the second carrying portion is located at the disc holding position in the third and fourth operating states.

A disc pick-and-place device including a disc pick-and-place body and a quantity sensing unit is provided. The disc pick-and-place body is for clamping and unloading at least one disc. The quantity sensing unit is disposed on the disc pick-and-place body for sensing the quantity of the at least one disc clamped on the disc pick-and-place body. The quantity sensing unit includes a movable piece and an optical distance measuring device. The movable piece leans on at least one disc and moves as the quantity of the at least one disc changes. The optical distance measuring device is for emitting a beam and receiving the beam reflected from the movable piece to detect the quantity of the at least one disc.

A disc drive has an opening portion for inserting a disc. The disc drive includes a driving unit, a moving member, a traverse, a disc positioning structure and a restoring structure. When the disc is intended to be clamped on the traverse, the driving unit drives the moving member to move the traverse to a disc holding position to clamp the disc; and the moving member moves the disc positioning structure to a disc release position so that the disc positioning structure does not contact the disc. When the disc is intended to be released from the traverse, the driving unit drives the moving member to move the traverse to a disc unloading position to unload the disc; and the restoring structure moves the disc positioning structure to a disc loading position to support the disc.

There is provided an optical disc drive that can maintain contact between an optical disc and a conveying roller, while allowing the number of components to be reduced. A conveying roller includes a right roller that is rotatable around an axis and a left roller that is rotatable around an axis. The right roller portion and the left roller portion are arranged in a lateral direction. One of a right end portion of the right roller portion and a left end portion of the left roller portion is movable in an up-down direction relative to the other of the right end portion of the right roller portion and the left end portion of the left roller portion, with a relative position between the axis and the axis unchanged.

A disc drive has an opening portion for inserting a disc. The disc drive includes a driving unit, a moving member, a traverse, a disc positioning structure and a restoring structure. When the disc is intended to be clamped on the traverse, the driving unit drives the moving member to move the traverse to a disc holding position to clamp the disc; and the moving member moves the disc positioning structure to a disc release position so that the disc positioning structure does not contact the disc. When the disc is intended to be released from the traverse, the driving unit drives the moving member to move the traverse to a disc unloading position to unload the disc; and the restoring structure moves the disc positioning structure to a disc loading position to support the disc.

A magnet structure includes first and second magnet units. The first magnet unit is provided with a first magnet fixing section that includes a first surface and a first magnet having a first polarity on the first surface's side. The second magnet unit is provided with a second magnet fixing section that includes a second surface and a second magnet having a second polarity on the second surface's side, the second polarity being an opposite polarity to the first polarity. The first and second surfaces are located next to one another on the same plane to form a magnetic attachment surface which is magnetically attached to a magnetically-attached object. The second magnet unit is supported by the first magnet unit so as to move in a predetermined range.

A magnet structure includes first and second magnet units. The first magnet unit is provided with a first magnet fixing section that includes a first surface and a first magnet having a first polarity on the first surface's side. The second magnet unit is provided with a second magnet fixing section that includes a second surface and a second magnet having a second polarity on the second surface's side, the second polarity being an opposite polarity to the first polarity. The first and second surfaces are located next to one another on the same plane to form a magnetic attachment surface which is magnetically attached to a magnetically-attached object. The second magnet unit is supported by the first magnet unit so as to move in a predetermined range.

A cam projection sliding in a cam slot of an arm causes the arm to proceed to an arm when a shutter is in the closed position or the open position and to recede from the arm when the shutter is sliding between the open position and the closed position. A spring is thereby considerably displaced, providing a satisfactory operation of the shutter.