An arc path forming unit, comprising: a magnet frame having an inner space, and comprising a plurality of surfaces surrounding the inner space; and main magnets coupled to the plurality of surfaces to form magnetic fields in the inner space, wherein the plurality of surfaces comprise: a first surface extending in one direction; a second surface disposed to face the first surface and extending in the one direction; and a third surface and a fourth surface extending from both end portions of the first surface and the second surface in the extending direction, respectively, at predetermined angles with the first surface and the second surface, and disposed to face each other, wherein the main magnets comprise: a first main magnet and a second main magnet disposed to be spaced apart from each other by a predetermined distance on any one of the first surface and the second surface; and a third main magnet and a fourth main magnet disposed to be spaced apart from each other by a predetermined distance on another one of the first surface and the second surface, wherein a first facing surface of the first main magnet facing the third main magnet has a polarity equal to a polarity of a third facing surface of the third main magnet facing the first main magnet, and wherein a second facing surface of the second main magnet facing the fourth main magnet has a polarity equal to a polarity of a fourth facing surface of the fourth main magnet facing the second main magnet, characterized in that the main magnets further comprise a fifth main magnet disposed on one of the third surface and the fourth surface; and a sixth main magnet disposed on another one of the third surface and the fourth surface, wherein a fifth facing surface of the fifth main magnet facing the sixth main magnet has a polarity different from a polarity of a sixth facing surface of the sixth main magnet facing the fifth main magnet. a magnet frame having an inner space, and comprising a plurality of surfaces surrounding the inner space; and main magnets coupled to the plurality of surfaces to form magnetic fields in the inner space, wherein the plurality of surfaces comprise: a first surface extending in one direction; a second surface disposed to face the first surface and extending in the one direction; and a third surface and a fourth surface extending from both end portions of the first surface and the second surface in the extending direction, respectively, at predetermined angles with the first surface and the second surface, and disposed to face each other, a first surface extending in one direction; a second surface disposed to face the first surface and extending in the one direction; and a third surface and a fourth surface extending from both end portions of the first surface and the second surface in the extending direction, respectively, at predetermined angles with the first surface and the second surface, and disposed to face each other, wherein the main magnets comprise: a first main magnet and a second main magnet disposed to be spaced apart from each other by a predetermined distance on any one of the first surface and the second surface; and a third main magnet and a fourth main magnet disposed to be spaced apart from each other by a predetermined distance on another one of the first surface and the second surface, a first main magnet and a second main magnet disposed to be spaced apart from each other by a predetermined distance on any one of the first surface and the second surface; and a third main magnet and a fourth main magnet disposed to be spaced apart from each other by a predetermined distance on another one of the first surface and the second surface, wherein a first facing surface of the first main magnet facing the third main magnet has a polarity equal to a polarity of a third facing surface of the third main magnet facing the first main magnet, and wherein a second facing surface of the second main magnet facing the fourth main magnet has a polarity equal to a polarity of a fourth facing surface of the fourth main magnet facing the second main magnet, characterized in that the main magnets further comprise a fifth main magnet disposed on one of the third surface and the fourth surface; and a sixth main magnet disposed on another one of the third surface and the fourth surface, a fifth main magnet disposed on one of the third surface and the fourth surface; and a sixth main magnet disposed on another one of the third surface and the fourth surface, wherein a fifth facing surface of the fifth main magnet facing the sixth main magnet has a polarity different from a polarity of a sixth facing surface of the sixth main magnet facing the fifth main magnet.