Recording media library apparatus with a function to detect a position of a recording medium transferred in the library

Abstract

Locking claw engages a recording medium to be transferred, and a determination is made as to which of a plurality of predetermined points a current position of the locking member corresponds to. Current position of the recording medium can be determined indirectly on the basis of the thus-determined predetermined point corresponding to the current position of the locking member. If any recording medium is not properly settled in a predetermined rest position at power-ON, then the recording medium is automatically transferred to be settled in the predetermined rest position. Simplified detection of the position of the locking claw is made in absolute or quasi-absolute form, by a picker position detector unit that is provided in association with a rotating drive shaft of the locking member and employs a simply-constructed mechanism capable of generating detection pulses responsive to predetermined rotational angles of two shafts rotating at different rates. Each of the plurality of predetermined points defined for the locking claw can be identified in absolute or quasi-absolute form on the basis of a combination of patterns of the thus-generated pulses. Thus, in feed transfer of a recording medium, such as a DVD medium, the position of the medium can be detected in a simplified manner and can be automatically controlled to be properly settled in the predetermined position upon power-ON.