Ignition timing and throttle position control

Claim 1

In combination with an internal-combustion engine having an induction passage for airflow to the engine, a throttle in said induction passage for controlling airflow therethrough, said throttle having fast and slow idle positions, a throttle lever connected to said throttle for controlling the position thereof, a vacuum unit for advancing the timing of ignition in said engine when vacuum signals are applied thereto, a vacuum conduit connected between said vacuum unit and said induction passage for transmitting vacuum signals from said induction passage to said vacuum unit, and an associated transmission with an input connected to said engine and an output connected to a load and with variable ratio drive means driving said output from said input, said variable ratio drive means providing high and low drive ratios wherein said low drive ratio reduces the speed of the output from the speed of the input to a greater extent than said high drive ratio: an ignition timing and throttle position control comprising a hollow elongated housing having first and second openings respectively located in opposite ends thereof and having a lateral opening located intermediate the ends thereof, said first opening forming a portion of said vacuum conduit for receiving vacuum signals from said induction passage, said lateral opening forming a portion of said vacuum conduit for supplying vacuum signals to said vacuum unit, said second opening being connected to atmosphere for venting said vacuum unit thereto, said first and second openings defining valve seats, a magnetically responsive plunger disposed within said housing and reciprocable between said valve seats, a solenoid coil surrounding said housing, switch means energizing said coil when said high drive ratio is operative, energization of said coil causing said magnetically responsive plunger to disengage the valve seat defined by said first opening and to engage the vaLve seat defined by said second opening to thereby permit advance of ignition timing by said vacuum unit, said switch means deenergizing said coil when said low drive ratio is operative, a spring which upon deenergization of said coil moves said plunger to disengage the valve seat defined by said second opening and to engage the valve seat defined by said first opening to prevent advance of ignition timing by said vacuum unit, and a stop member carried by said plunger and extending through said second opening adjacent said throttle lever, energization of said coil causing extension of said stop member into engagement with said throttle lever to thereby prevent closure of said throttle beyond a certain position, said certain position defining said fast idle position, deenergization of said coil permitting said spring to cause retraction of said stop member out of engagement with said throttle lever to thereby permit closure of said throttle to said slow idle position.