A variable resistor provided with a click mechanism comprising a metallic bearing, a slide member, a holder to which the slide member is attached, a leaf spring being placed in a cavity formed in the bearing. A protrusion formed integrally with the leaf spring being resiliently contacted with plurality...http://www.google.ca/patents/US4306216?utm_source=gb-gplus-sharePatent US4306216 - Variable resistor with click mechanism
