Control apparatus for air conditioning unit

Claim 1

A control apparatus for controlling the operation of a compressor motor of an air conditioning unit, comprising a power supply circuit, a manual switch connected to said power supply circuit for turning on and off the current supplied from said power supply circuit to said control apparatus, a temperature detector circuit operated in response to the indoor air temperature, said temperature detector circuit generating a signal for prohibiting the start and restart of said compressor motor when the indoor air temperature is within a predetermined range, said temperature detector circuit generating a signal for permitting the start and restart of said compressor motor when the indoor air temperature is not within said predetermined range, a main control circuit for sequentially generating, in response to the voltage produced by the current supplied by said manual switch, a signal for permitting the operation of said compressor motor and a signal for prohibiting the operation of said compressor motor, said main control circuit further producing a single initial pulse, a timer circuit for generating, in response to selected one of the signals generated by said temperature detector circuit and said main control circuit for prohibiting the operation of said compressor motor, a signal for prohibiting the restart of said compressor motor until the passage of a predetermined length of time, said timer circuit further producing a signal permitting the restart of said compressor motor after the lapse of said predetermined length of time, said timer circuit being reset by the initial pulse produced by said main control circuit, a logic gate operated in response to the output signals produced by said temperature detector circuit, said main control circuit and said timer circuit for effecting selected one of prohibition and permission of the operation of said compressor motor, said logic gate producing a signal for supplying current to said compressor motor when all of said temperature detector circuit, said main control circuit and said timer circuit produce a signal permitting the operation of said compressor motor, said logic gate producing a signal for cutting off the current flow in said compressor motor when at least one of said temperature detector circuit, said main control circuit and said timer circuit produces a signal prohibiting the operation of said compressor motor, switch means for turning on and off the current flow in said compressor motor in response to the output signal of said logic gate, and an auxiliary control switch connected in parallel to said manual switch, said auxiliary control switch being turned on at least during the period of the presence of said signal prohibiting the restart of said compressor motor, in response to the signal generated by said timer circuit for prohibiting the restart of said compressor motor.