Vehicle instrument panels typically include numerous switches, such as variable potentiometers, which are inserted through apertures formed in the instrument panel and are electrically connected for providing various electrical operations in the vehicle, such as instrument panel light dimming, heating ventilation and air conditioning (HVAC) control, etc. These switches typically include a metal spring installed with the switch which engages the rear surface of the instrument panel for retaining the switch in the instrument panel aperture. Typically, the switch assemblies are installed in the vehicle by hand, therefore low insertion forces are required. Additionally, electrical connectors are subsequently attached to the rear of the switch assembly once it has been installed in the instrument panel aperture, therefore high retention forces are required to prevent inadvertent removal during such subsequent attachment. For example, typically at least approximately 80 Newtons of minimum push-out force is required to prevent unwanted detachment of the switch assembly from the instrument panel aperture. An additional requirement for such switch assemblies is that they must be removable for servicing.
A problem with the metal springs referenced above is that they add cost by requiring the manufacture, handling and assembly of such spring components.
Accordingly, it is desirable to eliminate the metal spring from the assembly to reduce cost while maintaining low insertion forces and high retention forces.
Another problem addressed by the present invention is that of the limitations of rotary potentiometers used in vehicle instrument panels, such as for dimmer switches. The rotary potentiometers used in vehicle instrument panel assemblies are similar to those of home audio systems, which do not have significant customer torque requirements. However, in a vehicle, substantial torque resistance is required. It is therefore desirable to provide an improved switch assembly which provides substantially improved torque resistance to enable use of such a potentiometer in a vehicle.