An electric potentiometer including a wiper lever having brush wipers, which upon a rotational movement about a pivot shaft sweep over electrically conductive layers applied to a carrier plate. A resistor layer is joined at one end to a connection layer and at the other to a grounded connection layer. The layer is joined at one end to a pickup connection layer and at the other, via a supplementary layer resistor, to the connection layer. A sliding layer of electrically non-conductive paste material is disposed between the carrier plate and the resistor layer, the latter of which is formed from a paste material provided with carbon particles. The sliding layer is wider than the width of the wiper and the resistor layer.

A variable resistor (102) for varying a resistance between first and second terminals (145, 150) includes a substrate (200) having formed thereon a resistor network (205) for providing the resistance, wherein the resistor network (205) is electrically coupled between the first and second terminals (145, 150). The variable resistor (102) further includes an elastomeric actuator (300) having opposing upper and lower surfaces (310, 305), wherein the lower surface (305) is conductive. The lower surface (305) electrically couples the first terminal (145) to successive portions of the resistor network (205) as an increasing force is applied to the upper surface (310) of the elastomeric actuator (300), in response to which the resistance between the first and second terminals (145, 150) varies.

Pressure sensitive direction devices are provided which may facilitate assembly and provide higher tolerance for variation in alignment of components while still providing for pressure sensitive direction detection. The devices of the present invention may be particularly advantageous when integrated into devices, such as cellular radiotelephones, to provide a user interface to facilitate user navigation through increasingly complex menu structures. In various embodiments, the present invention may detect pressure in addition to two and, preferably, at least four directions. In particular embodiments, the devices of the present invention provides a switching device having a plurality of trace grid areas located, for example, on a printed circuit board and actuated responsive to pressure applied by a user through a poly-dome layer where increase pressure results in contact with a greater number of the traces in respective grids. Alternative embodiments include trace patterns which are substantially circumferentially arranged in patterns configured to detect user input. A select switch is included in various embodiments of the present invention.

A strip conductor comprises a first layer with at least one curved section. At least one region of the curved section provided with an additional layer having a smaller resistivity than the first layer. The at least one region is constructed such that resistance on tracks of different radii of curvature is approximately equalized.

A chip-type variable resistor is provided which includes an insulating substrate formed with a resistor strip which is arcuate at least partially and has both ends electrically connected to respective extremity electrode terminals, an intermediate terminal member mounted to the substrate, and a contact member electrically connected to the intermediate terminal member and rotatably mounted to the substrate in slidable contact with the resistor strip. The resistor strip includes at least one portion having a lower area resistivity (defined as a resistance per unit surface area) and at least another portion having a higher area resistivity.