Abstract: A rotary control knob apparatus includes a stationary knob retainer having a cylindrical post and an annular knob that slides over the retainer post, where the exterior periphery of the retainer post has a distributed array of compliant protrusions that contact the inner periphery of the knob to provide a resilient sliding interference fit between the knob and the retainer post. In a preferred arrangement, the retainer is secured against the rear surface of a control panel trimplate, and the knob is axially captured between the trimplate and a retainer flange extending radially outward from the base of the cylindrical post.

Abstract: An improved capacitive touch panel includes a trimplate defining a non-planar touch surface, a planar array of capacitive sensing elements mounted behind the trimplate, and a formable interface element of high relative static permittivity sandwiched between the sensing elements and the inboard face of the trimplate. The interface element is a compression molded silicone rubber element having a first major surface that is sculpted to match and uniformly contact the inboard face of the trimplate, and a second major surface that is planar and uniformly contacts the planar array of capacitive sensing elements. The interface element has a limited amount of compliance so that slight compression of the interface element between the trimplate and sensing elements eliminates any air gaps between the contacting surfaces.