PURPOSE:To move a cassette smoothly and securely in a stable state free of play, etc., through simple structure, by providing fixed guide grooves at a cassette frame side and fitting moving guide members and a projection part to be guided on a cassette receiving base in the guide groove. CONSTITUTION:When a motor is driven while the cassette receiving base B is at a cassette loading/unloading position, its rotation force is transmitted to a driving pinion 21 through a worm gear mechanism, worm gear 22, and driving arm 24. A driven pinion 20 rotates synchronously to rotate and move both pinions 20 and 21 along racks 18 and 18, and consequently the cassette receiving base B moves back horizontally and then moves down vertically to be set at an operation position under the guidance of the moving device consisting of fixed guide grooves 4 and 4 of a cassette frame A, guided plates 14 and 14 of the cassette receiving base B, and moving guide members 9 and 9.