Automatic engine stop-restart system

A system for automatically stopping and restarting a motor vehicle engine having an alternator that is coupled to said engine in response to predetermined conditions comprising:

• stopping means coupled to said engine for stopping said engine;
• starting means coupled to said engine for restarting said engine;
• engine rotational speed sensor means coupled to said engine for detecting an engine's rotational speed to generate a speed signal corresponding to said engine's rotational speed;
• alternator output level sensor means coupled to said alternator for detecting an output level of said alternator to generate an alternator signal corresponding to said output level;
• a first judging means coupled to said engine's rotational speed sensor means for judging as to whether said speed signal indicates said engine's rotational speed exceeding a predetermined level to produce a first signal indicative of said engine being rotating;
• a second judging means coupled to said alternator output level sensor means for judging as to whether said alternator signal indicates the output level exceeding a predetermined level to produce a second signal indicative of said alternator being generating;
• switching means manually operated for producing a third signal while said switching means is turning on;
• a third judging means coupled to said first and second judging means and said switching means for producing an enable signal when at least said first, second and third signals are received by said third judging means;
• a fourth judging means coupled to said third judging means and various sensors detecting engine operational conditions for judging as to whether a first condition for automatic engine stop is fulfilled to produce a first activating signal when fulfilled, said first condition including at least a presence of said enable signal, and said stopping means being energized by said first activating signal;
• and
• a fifth judging means coupled to said third judging means and said various sensors for judging as to whether a second condition for automatic engine restart is fulfilled to produce a second activating signal when fulfilled, said second condition including the presence of said enable signal, and said starting means being energized by said second activating signal.