Card upside-down insertion preventative apparatus

A card upside-down insertion preventive apparatus comprising a truncated corner portion formed at one end of a leading edge portion of a square card, a card tray disposed in a card insertion chamber communicating with a card inlet port, said card tray having a front abutment member and capable of moving in accordance with insertion of said card, the leading edge of said card being brought into abutment with said front abutment portion when said card is inserted through said card inlet port, a lock claw formed on said card tray, said lock claw being capable of displacing upwardly and downwardly in a direction perpendicular to the card insertion direction, a pressure receiving portion formed on said claw so as to cooperate with a region within said truncated corner portion of said card when the card is in abutment with said front abutment member and inserted right side up, said pressure receiving portion causing said lock claw to displace downwardly by being pressed by a non-truncated corner portion formed at the other end of said front edge portion of said card when said card is inserted upside down, and an engagement portion formed at a location corresponding to a lower surface of said card tray and adapted to engage said lock claw when said lock claw has displaced downwardly so as to prevent movement of said card tray.