Adjustable rotary switch

Claim 1

A rotary switch calibrated for accurately selecting any one of a plurality of combinations of external circuits connected to the switch, the combinations being made in accordance with a predetermined code, said rotary switch comprising a housing having one end open and a housing wall with a centrally disposed aperture and a noncentrally located opening therein, an insulating substrate having a plurality of electrical contact paths for effecting said code and arranged in multiple concentric rings in the surface thereof, the surfaces of said contact paths being flush with the surface of said insulating substrate, a rotor comprising an insulating annular body and having teeth means for calibration of said switch and located at a portion of the circumference of said rotor, contactor means having multiple rake contactors and secured to said rotor for engaging selected combinations of contact paths in different ones of said rings whereby rake contactor surface areas engaging said paths remain constant despite wear, shaft means mounted in said switch to preclude axial movement thereof and coupled to said rotor to support and position said rotor in relationship to said housing and insulating substrate having the contact paths therein, said shaft means having tool adjustment means at one end thereof, and a cover secured to said housing to enclose said open end and having a cover aperture therein, said shaft means journalled in said cover aperture, whereby said tool adjustment means is accessible through said centrally disposed aperture and said teeth means accessible through said noncentrally located opening for adjustable positioning of said rotor and contactor means relatively to said shaft means and contact paths prior to fixing said rotor to said shaft means to calibrate said switch and effect precise switching accuracy in the selection of a combination of said external circuits.