Abstract: An operating mode switching unit for a bicycle includes a rotary knob disposed on a front surface of a panel and connected to a plate-shaped spring unit by an axle. The spring unit includes a first spring portion which can be elastically deformed in the direction toward the axle. A second spring portion which can be elastically deformed in the direction toward the panel is disposed nearer to the axle. The first spring portion has a first protrusion projecting radially outward, and the second spring portion has a second protrusion projecting in the direction away from the panel. The panel is formed in its rear surface with a wall having indentations into which the first protrusion can snap. A laminate member faces the rear surface of the spring unit and includes plural pairs of opposing switch contacts. Each pair of contacts are pressed to contact with each other by the second protrusion.

Abstract: An air plasma arc cutter includes spaced apart front and rear panels. A partition wall has its opposed two edges coupled to the front and rear panels to divide the space therebetween into upper and lower regions. An AC-to-DC voltage converter is disposed in the upper region and converts an AC voltage to a DC voltage to be applied between a torch electrode of a torch of the cutter and a workpiece. An air compressor supplies compressed air around the torch electrode and is disposed in the lower region. The air compressor has a threaded bolt which extends through the partition wall from the lower into upper regions. A nut is screwed onto the bolt in the upper region to thereby secure the air compressor to the partition wall. Shock absorbing members are disposed between the nut and the partition wall and between the air compressor and the partition wall.