Abstract: Disclosed is a slim-type high speed rotation optical disk apparatus having a turn table for loading an optical disk thereon. As compared with conventional ones, a brake pad is located near to the front end so that the brake pad comes into tight contact with a side of the tray's front portion when the tray is inserted. This reduces the noise and vibration of the optical disk apparatus.

Abstract: The present invention relates to a method of recovering energy from the turntable motor (12) in an optical disc drive comprising a power supply and a circuitry (10) that is capable of selectively feeding a current from the power supply into the motor in a first state and from the motor into the power supply in a second state, the method comprising the steps of: decelerating the motor, during decelerating the motor, repeatedly calculating a ratio between a duration of the first state and a duration of the second state in dependence on an angular velocity of the motor, such that a current integrated over the whole decelerating process is fed from the motor into the power supply, and after calculating the ratio, selecting the duration of the first state and the duration of the second state in accordance with the calculated ratio. The present invention further relates to an optical device.

Abstract: A disc braking device is utilized in an optical disc drive. The disc braking device is installed on a disc tray of an optical disc drive. Without being affected by an covering component or the location of the disc braking device, the disc braking device makes a disc stop rotating in a more direct and efficient way. The disc braking device contains a structure portion; a braking rod installed and not fixed on the structure portion; and a braking component installed on the braking rod and utilized for making the disc stop rotating.

Abstract: A motor driver has a braking control circuit. The braking control circuit shuts off the supply of an electric current to the coils included in the motor when a motor control signal shifts to a predetermined level and, after a predetermined length of time secured in accordance with an index signal, starts application of braking to the rotation of the motor by the use of a braking circuit. The index signal is obtained from the signal that indicates the rotational position of the motor. The motor control signal is fed from a control signal generating circuit to the braking control circuit.

Abstract: A method and circuit for braking a forward rotation of a rotor of a polyphase DC motor. A commutation sequencer is incremented by several phases to produce an incremented commutation sequence to produce a magnetic flux vector that lags a magnetic pole of the motor. Driving currents are applied to coils of the motor in accordance with the incremented commutation sequence to brake the rotor. The method is implemented in a circuit that has a sequencer for incrementally generating sets of commutation signals to select stator coils for energization to rotate the rotor. A power stage to which the commutation signals are applied energizes the selected coils in accordance with the commutation signals. A circuit interrupts the energization of the selected coils and the commutation sequence is altered to produce a sequence that produces a negative torque on the rotor.

Abstract: A self-winding spring starter for rotating data storage devices. The spring is fixed on one end to a chassis or a cowling. The spring selectively engages the rotating assembly at its other end via a clutch when the rotating assembly is being stopped. The assembly stops, reverses, and fully stops again before being locked into place by a brake. The spring thus winds, unwinds, and re-winds, cocking itself in the appropriate direction for re-start.

Abstract: The present invention relates to a turntable brake for a disc player capable of preventing a turntable from rotating when a disc is improperly loaded on the turntable. In accordance with the invention, the turntable brake which employs first and second magnets is provided. When the disc is correctly loaded on the turntable, two magnets are directly contacted with each other, thereby permitting the rotation of the turntable. When the disc is improperly loaded on the turntable, two magnets are separated from each other, thereby preventing the turntable from rotating.

Abstract: A magnetic disk drive includes a spindle for rotating a plurality of magnetic disks and a lock mechanism for preventing the spindle from rotating when the magnetic disk drive is not operated. A toothed disk is provided on an axial end of the spindle, and a movable lock arm engageable to teeth of the toothed disk is provided. The lock arm is driven to lock the rotation of the spindle by a solenoid which is energized after a predetermined period of time has elapsed after the electric power of the disk drive is turned off, so that the lock mechanism locks the spindle after the rotation of the spindle and magnetic disks completely stop.

Abstract: A record player is provided with a turntable brake for instantly stopping the turntable of the record player in playback when desired and a pair of balance wheels for permitting slant of the turntable within a predetermined range when manually operating the turntable. The turntable hereof has a peripheral drum portion extending downwardly from its bottom and a rubber shoe is mounted on one end of a pivoted lever arm. The lever arm is adapted to be actuated to press the rubber shoe against the drum portion of the turntable for stopping rotating movement of the turntable by means of friction.

Abstract: A high-density information recording carrier such as an optical disk which is used for recording and/or playing back information carried on a plastic substrate by means of laser beams has an improved protective layer between a recording layer and the plastic substrate. The protective layer is made of inorganic glass made of alkali-free glass containing less than 1 wt % of alkali metal oxides. The resulting optical disk shows improved durability, higher C/N, lower BER and higher film forming rate.

Abstract: A recording or reproducing device in which current is supplied to the spindle motor which drives the disk to produce reverse torque in response to a stop signal when the disk is rotating. The beginning of reverse rotation is detected and the supply interrupted in response thereto.

Abstract: In a record-disc player comprising a disc-braking mechanism the turntable (7) is covered by a lid (14) which is pivotally connected to a housing (3). The lid (14) is latched in a closed position by means of a latching mechanism (30). A brake lever (21) is pivotally connected to the lid (14) and carries a braking element (23) and a stop element (24) arranged on opposite sides of the pivot. The latching mechanism (30) can be released by exerting pressure on the lid (14), the stop element (24) engaging with a stop portion (44) as a result of the pressure exerted on the lid. By the pivotal movement of the lever (21) relative to the lid (14) a braking torque is exerted on the disc loader (20) by the braking element (23), so that the disc (13) is stopped.

Abstract: A turntable brake mechanism comprises a brake shoe located beneath the turntable for motion between a raised position and a lowered position in response to raising and lowering a record lifting rod which passes through one of the slots in the turntable to transfer the record between the turntable and a set of record receiving pads positioned above the turntable. When raised, the brake shoe engages the underside of the turntable to oppose the rotation of the turntable. The brake shoe is spaced from the turntable, when retracted, to allow the turntable to rotate freely.

Abstract: A rotation control device for a magnetic disk drive apparatus, which provides electrical regenerative braking of the apparatus prior to and continuously with actuation of an electro-mechanical braking system, once power is cut off to the apparatus. The use of electrical regenerative braking minimizes wear on the mechanical braking components and reduces maintenance on the apparatus. The use of electro-mechanical braking at low speeds assures reliable continuous braking when the electrical regenerative braking becomes relatively ineffective at low speeds.

Abstract: A record player has a turntable, a drive means to turn the turntable, a position detecting means for detecting the rotational position of the turntable and a stopping means for stopping the turntable. The stopping means is operated by a detecting output from the position detecting means so as to stop the turntable at a predetermined position.

Abstract: A dual lock mechanism for a magnetic disc drive whereby rotation of the disc spindle and translation of the carriage assembly can be prevented. A first lock arm is pivotally mounted whereby one end can engage the spindle drive motor. A connector link is operated in response to rotation of the first lock arm and pivots a second lock arm within the housing into engagement with the carriage assembly.

Abstract: In video disc players, a turntable is raised and lowered by means of an actuating cam to transfer a record retained inside the player between the turntable and a record receiving means. A spring-loaded member is disposed underneath the turntable for engagement therewith as the turntable is lowered for reducing the force exerted by the turntable on the actuating cam.