System for time programming of states by communicating time data via a continuously rotatable potentiometer

A programmable thermostat for control of a temperature modifying apparatus comprising:

• a mode selection means for selection of one of a program mode and a control mode;
• an operator adjustable rotary potentiometer having an adjustment knob with a mark thereon, an associated printed time indicia corresponding to twenty four hours of time disposed concentric with said adjustment knob and a printed temperature indicia corresponding to temperature disposed concentric with said adjustment knob, said rotary potentiometer being rotatable through 360.degree. via said adjustment knob, said mark on said adjustment knob indicating a corresponding time on said time indicia and a corresponding temperature on said temperature indicia, said rotary potentiometer having a pair of fixed terminals and a single rotary terminal, the resistance between said rotary terminal and one of said fixed terminals corresponding to the rotary position of said adjustment knob and thereby further corresponding to both said time in said time indicia indicated by said mark and said temperature in said temperature indicia indicated by said mark;
• a time signal means connected to said rotary potentiometer for generating a time signal indicative of a time corresponding to the resistance between said rotary terminal of said rotary potentiometer and one of said fixed terminals of said rotary potentiometer and thereby further corresponding to said time in said time indicia indicated by said mark;
• a manual control state input means for selection of a temperature offset;
• a program memory means for storing therein a program of temperature offsets for particular times of a single 24 hour day;
• a programming means connected to said mode selection means, said time signal means, said manual temperature offset input means and said program memory means for writing an indication of said selected temperature offset in said program memory means at a location corresponding to said time signal when in program mode;
• a clock means for generating a clock signal indicative of the current time;
• a set point temperature signal means connected to said rotary potentiometer for generating a set point temperature indicative of a temperature corresponding to the resistance between said rotary terminal of said rotary potentiometer and said one of said fixed terminals of said rotary potentiometer and thereby further corresponding to said temperature in said temperature indicia indicated by said mark;
• and
• a control means connected to said mode selection means said program memory means, said clock means and said set point temperature signal means for recalling from said program memory means the temperature offset corresponding to the current time indicated by said clock signal and for thermostatic control of the temperature modifying apparatus for maintaining a temperature equal to the sum of the set point temperature indicated by said set point temperature signal and said recalled temperature offset when in control mode.