PURPOSE: To reduce the size of an electronic photographing device without needing two motors serving as a drive source.

CONSTITUTION: A power switching device comprises first and second shafts 40 and 41; a first one-way gear 46 incorporating a first one-way bearing 45: a second one-way gear 48 incorporating a second one-way bearing 47: and a third one-way gear 50 incorporating a third one-way bearing 49. Further, the power switching device comprises a first output gear 51 engaged with the first one-way gear 46; a second output gear 54 engaged with the second one-way gear 48 and the third one-way gear 50; and a motor 42 coupled to one of the first and second shafts 40 and 41. By running forward and reversing one motor 42, the first output gear 51 is rotated and stopped and the second output gear 54 is always rotated in the same direction.