Ignition system for an internal combustion engine

Claim 2

Ignition system for an internal combustion engine comprising ignition plug means, first breaker means for determining a standard ignition timing for normal operation of the engine, second breaker means for providing at least two retarded ignition timings including a first retarded timing and a second retarded timing which is less retarded than the first retarded timing, and sequential advance means for changing the ignition timing from said first retarded timing to said second retarded timing and then to said standard ignition timing during engine starting to thereby sequentially advance said ignition timing.

Claim 3

Ignition system for an internal combustion engine in accordance with claim 1 in which said sequential advance means includes timer means.

Claim 4

Ignition system for an internal combustion engine in accordance with claim 1 which further comprises ignition timing advance means for advancing at least said standard ignition timing in accordance with at least one of engine speed and engine intake pressure.

Claim 5

Ignition system for an internal combustion engine in accordance with claim 3 in which said advance means is so arranged that said second retarded timing is also advanced at least in accordance with the engine speed.

Claim 6

In an ignition system for an internal combustion engine, an ignition timing control device including first breaker means for providing a standard ignition timing for normal engine operation, second breaker means for providing at least two retarded ignition timings including a first retarded timing and a second retarded timing which is less retarded them the first retarded timing, first timer means for advancing the ignition timing from said first retarded timing to said second retarded timing after a first predetermined time after engine start, and second timer means for advancing the ignition timing from said second retarded timing to said standard timing.

Claim 7

In an ignition system for an internal combustion engine, an ignition timing control device including first breaker means for providing a standard ignition timing for normal engine operation, second breaker means for providing at least two retarded ignition timings including a first retarded timing and a second retarded timing which is less retarded them the first retarded timing, first timer means for advancing the ignition timing from said first retarded timing to said second retarded timing after a first predetermined time after engine start, and second timer means for advancing the ignition timing from said second retarded timing to said standard timing.

Claim 8

An ignition timing control device in accordance with claim 5 in which said first breaker means includes a cam provided on a shaft which is adapted to be driven by the engine and breaker contacts comprising a stationary contact mounted on a stationary disc and a movable contact adapted to be actuated by said cam so that it is moved into and out of contact with said stationary contact, and said second breaker means includes a second cam provided on said shaft and at least two pairs of breaker contacts whiCh are opened at two different timings retarded more than the opening timing of the contacts in said first breaker means.

Claim 9

An ignition timing control device in accordance with claim 6 in which means is further provided for centrifugally shifting the angular phase of said shaft so as to provide an ignition timing advance in accordance with the engine speed.

Claim 10

An ignition timing control device in accordance with claim 6 in which means is further provided for shifting the angular position of said stationary disc in accordance with the engine intake pressure.

Claim 11

In an ignition system for an internal combustion engine, an ignition timing control device comprising a cam provided on a shaft which is adapted to be driven by the engine, a first pair of breaker contacts including a stationary contact mounted on a disc and a movable contact, a second pair of breaker contacts including a stationary contact mounted on said disc and a movable contact adapted to be actuated by said cam into and out of contact with said stationary contact, the timing of opening of said second pair of contacts being retarded more than that of said first pair of contacts, means for shifting the angular position of said disc by a predetermined angle so that the opening timing of said second pair of contacts is further retarded, and timing means for deenergizing said shifting means after a first predetermined time from engine start and for cutting-off said second pair of contacts from the ignition circuit after a second longer predetermined time from engine start.

Claim 12

In an ignition system for an internal combustion engine, an ignition timing control device comprising a cam provided on a shaft which is adapted to be driven by the engine, a first pair of breaker contacts including a stationary contact mounted on a disc and a movable contact, a second pair of breaker contacts including a stationary contact mounted on said disc and a movable contact adapted to be actuated by said cam into and out of contact with said stationary contact, the timing of opening of said second pair of contacts being retarded more than that of said first pair of contacts, means for shifting the angular position of said disc by a predetermined angle so that the opening timing of said second pair of contacts is further retarded, and timing means for deenergizing said shifting means after a first predetermined time from engine start and for cutting-off said second pair of contacts from the ignition circuit after a second longer predetermined time from engine start.

Claim 13

An ignition timing control device in accordance with claim 9 in which means is provided for centrifugally shifting the angular phase of said shaft so as to provide an ignition timing advance in accordance with the engine speed.

Claim 14

An ignition timing control device in accordance with claim 9 in which means is further provided for shifting the angular position of said stationary disc in accordance with the engine intake pressure.

Claim 15

Ignition system for an internal combustion engine comprising ignition plug means, breaker means for providing a standard ignition timing for normal operation of the engine and at least two retarded ignition timings including a first retarded timing and a second retarded timing which is less retarded than the first retarded timing, and means for changing the ignition timing from said first retarded timing to said second retarded timing and then to said standard timing during engine starting to thereby sequentially advance said ignition timing.

Claim 16

Ignition system for an internal combustion engine comprising ignition plug means, breaker means for providing a standard ignition timing for normal operation of the engine and at least two retarded ignition timings including a first retarded timing and a second retarded timing which is less retarded than the first retarded timing, and means for changing the ignition timing from said first retarded timing to said second retarded timing and then to said standard timing during engine starting to thereby sequentially advance said ignition timing.