A needle having a shaft; a neck at the distal end of the shaft; and a tapered end at the distal end of the neck, the tapered end comprising at least three planar faces meeting at a central point, and an annular shoulder adjacent to the neck. A pair of rear horizontal frames extend in the fore-and-aft direction above corresponding rear wheels. If the magnets are electromagnets supplied with alternating current, the electricity generator operates both when the wheel is rotating and when the wheel is stationary. The flange 4 does not include tape 9 laid in the circumferential direction of the flange, because such tape would impede the forming of the flange material to form the flange. The command processor may be configured to selectively control, according to the commands received from a user through the input device, the relative size, position, or the like of each window presented on the display.