Abstract: A multi-rotation type potentiometer having an additional stopper member rotatable so as to set a rotation angle of the potentiometer or its sliding member to any angle.

Abstract: A housing for use with a variable resistor consisting of a spiral resistance element, a rotary shaft, a conductive slide plate and a top is disclosed. The housing includes a cylindrical body for supporting on its inner surface the resistance element, a first cylindrical panel engaged with one open end of the cylindrical body to close the open end and rotatably supporting the rotary shaft, a second cylindrical panel engaged with the other open end of the cylindrical body and rotatably supporting the rotary shaft, at least one pair of resilient engaging projections extended from at least one of the first and second cylindrical panels along the axis of the cylindrical body, and engaging recesses formed on an outer periphery of the cylindrical body at predetermined positions and respectively engaging with the resilient engaging projections when the first and second cylindrical panels are engaged with the cylindrical body to make up the housing for the variable resistor.

Abstract: A rotary support device for use with a dial apparatus is disclosed. The rotary support device is formed mainly of a first cylinder having an aperture through which a rotary shaft of the dial apparatus passes, the rotary shaft being then fixed thereto, a second cylinder having an aperture through which the rotary shaft passes with a clearance therebetween, and a coupling member which resiliently couples the first and second cylinders. The second cylinder is coupled to a rotating member of the dial apparatus and they are to be rotated together, so that when the rotating member of the dial apparatus is rotated, the rotary shaft of the dial apparatus is rotated through the second cylinder, the coupling member and the first cylinder even if the axis of the rotary shaft is eccentric to the axes of the support cylinders.

Abstract: A helical rotary switch having a helical coil formed of an insulating band like plate, a plurality of contact segments attached to said helical coil, a shaft for said helical coil rotatably supported by a pair of panels, a supporting member supported by said panels and supporting said helical coil between said pair of panels, and a sliding member with contact members engageable with said helical coil and said contact segments. The sliding member is mounted on said shaft such that when the shaft is rotated, said contact members of said sliding member successively contact the plurality of contact segments attached to said helical coil.