Spark control valve for ignition distributors

Claim 1

SPARK TIMING CONTROL APPARATUS FOR AN INTERNAL COMBUSTION ENGINE WHICH ENGINE INCLUDES AN AIR INDUCTION PASSAGE INCLUDING A VENTURI PROVIDING A SOURCE OF VENTURI VACUUM, AN ENGINE MANIFOLD PROVIDING A SOURCE OF MANIFOLD VACUUM AND A THROTTLE VALVE IN THE AIR INDUCTION PASSAGE, COMPRISING VACUUM ACTUATED SPARK ADVANCE MECHANISM, FIRST MEANS INCLUDING A FIRST RESTRICTED PASSAGE HAVING A SPARK VALVE AND A SEPARATE THROTTLE ACTUATED VALVE CONNECTED IN SERIES THEREIN FOR CONNECTING SAID SPARK ADVANCE MECHANISM TO THE SOURCE OF MANIFOLD VACUUM, SECOND MEANS INCLUDING A SECOND RESTRICTED PASSAGE BETWEEN SAID SPARK ADVANCE MECHANISM AND SOURCE OF VENTURI VACUUM FOR BLEEDING OFF A PORTION OF SAID MANIFOLD VACUUM AND FOR CONNECTING SAID SPARK ADVANCE MECHANISM TO SAID SOURCE OF VENTURI VACUUM, AND THIRD MEANS INCLUDING A THIRD RESTRICTED PASSAGE BETWEEN SAID SPARK ADVANCE MECHANISM AND THE SOURCE OF MANIFOLD VACUUM DISTINCT FROM SAID FIRST MEANS FOR BLEEDING OFF A PORTION OF SAID VENTURI VACUUM.