Patent ID: 8395111
Filing Date: 2013-03-12
Classification: G01D,G01P,G06F,H01H

Abstract:
1. A system for detecting rotation of a knob in an apparatus, the system comprising: a shaft having a predetermined length and a first end and a second end, the second end having an oblique reflective surface defined thereon, the first end fixedly attached to the knob; a rotation body containing the shaft, the rotation body having a receptacle to accommodate the second end of the shaft, the oblique reflective surface of the second end being exposed; an optical module on an integrated circuit substrate and optically coupled to the rotation body, the optical module detecting light irradiance from the exposed oblique reflective surface, the optical module including, a solid state light source; a plurality of photo detectors each of which generate an electrical signal upon exposure to at least a threshold amount of light, arranged about the light source on a plane in at least two pairs, each pair defining a first and a second direction parallel to the plane, the first and the second directions being perpendicular to each other; wherein the knob is equipped with a spring, the knob being movable between a rest position and a moved position, the moved position being attained in response to the application of a vertical force upon the knob, the spring returning the knob to the rest position upon release of the vertical force; and wherein the moved position of the knob is at least one of the following: a pulled position, a pushed position;