Releasable carriage drive unit for an optical disc player

Claim 1

An optical disc player comprising a rotatable disc spindle and a read objective which is arranged on a movable carriage for radial translational displacement of the objective relative to an optically readable disc which is disposed on the disc spindle between a minimum and a maximum radial distance between which the information to be read is contained on a disc, and comprising a drive unit for driving the carriage by cooperation of a drive pinion and a gear rack, which drive unit comprises: connected to the frame, an electric motor with a motor spindle which is rotatable about an axis of rotation, said drive pinion being rotatably journalled on the frame, a gear wheel coaxially connected to the drive pinion, and a primary pinion for driving the gear wheel, the primary pinion being rotatably journalled on a pivoting member which is journalled on the frame and is pivotable to a limited extent about a pivoting axis between a swung-out position and an operating position, resilient means for resiliently loading the pivoting member towards its operating position, in which the primary pinion and the gear wheel being in resilient engagement with each other, which resilient means have such a spring constant that, for a quick translational displacement of the carriage during work on the disc player the primary pinion can readily be disengaged from the gear wheel by hand by pivoting the pivoting member out of its operating position and that, in the event of the movement of the carriage being blocked, the pivoting member is swung-out as a result of the forces acting between the teeth of the primary pinion and the teeth of the gear wheel, so as to prevent excessive mechanical loading of said teeth or any other parts of the disc player, or to prevent thermal overloading of said electric motor.