Ignition system for rotary piston internal combustion engine

Claim 2

In an ignition system for a rotary piston internal combustion engine including two ignition plugs carried by said engine and exposed to a common combustion chamber from the internal housing surface thereof, and ignition circuits for respective plugs, the improvement wherein: one of said ignition circuits includes primary contact points opening at normal timing position and secondary contact points opening at delayed timing position and said system further comprising means for switching ignition from said primary to said secondary contact points when said engine operates at low speed and/or low load.

Claim 3

An ignition system as claimed in claim 1 further comprising a switching relay coil, a vacuum diaphragm switch and a switch responsive to engine speed, and said means for switching from said primary to secondary contact points is responsive to operation of said switching relay coil, and said vacuum diaphragm switch and said engine speed responsive switch are series connected with said relay coil.

Claim 4

An ignition system for a rotary piston internal combustion engine comprising: two ignition plugs carried by said engine and exposed to a common combustion chamber from the internal surface thereof, respective ignition circuit means connected to said plugs, one of said ignition plugs being disposed in leading relationship with respect to the direction of rotation of the engine and the other in trailing relationship therewith, a pair of ignition coils and distributors for providing an electrical spark across respective ignition plugs, an interrupting device and a distributing device provided on the distributor for the tailing ignition plug, said interrupting device including primary contact points for operation under normal conditions, and secondary contact points for delayed opening and at a predetermined angle from the normal contact points, a first normally closed switch adapted to open when engine r.p.m. exceeds a predetermined value, a normally closed vacuum diaphragm switch adapted to open when the intake vacuum increases to a predetermined value, a switching relay having a normally closed contact and a relay coil and normally open contacts operating to close when the relay coil is energized, said switching relay being operatively coupled to said interrupting device, such that, when said relay coil is energized, said first contacts are connected tO the normal primary contact points and said second contacts are connected to the secondary contact points, and means for energizing said relay coil when said vacuum diaphragm switch and said engine r.p.m. switches are closed.

Claim 5

An ignition system for a rotary piston internal combustion engine comprising: two ignition plugs carried by said engine and exposed to a common combustion chamber from the internal surface thereof, respective ignition circuit means connected to said plugs, one of said ignition plugs being disposed in leading relationship with respect to the direction of rotation of the engine and the other in trailing relationship therewith, a pair of ignition coils and distributors for providing an electrical spark across respective ignition plugs, an interrupting device and a distributing device provided on the distributor for the tailing ignition plug, said interrupting device including primary contact points for operation under normal conditions, and secondary contact points for delayed opening and at a predetermined angle from the normal contact points, a first normally closed switch adapted to open when engine r.p.m. exceeds a predetermined value, a normally closed vacuum diaphragm switch adapted to open when the intake vacuum increases to a predetermined value, a switching relay having a normally closed contact and a relay coil and normally open contacts operating to close when the relay coil is energized, said switching relay being operatively coupled to said interrupting device, such that, when said relay coil is energized, said first contacts are connected tO the normal primary contact points and said second contacts are connected to the secondary contact points, and means for energizing said relay coil when said vacuum diaphragm switch and said engine r.p.m. switches are closed.