Ignition timing responsive to transmission setting

Claim 1

In an ignition system for an automotive internal combustion engine combined with a manually controlled transmission system having a fork rod operatively connected with a speed selector lever through a striking rod and a shifting rod rigidly connected with said fork rod, said fork rod being provided in its peripheral wall with a recess located suitably to detect a predetermined speed range selected by the movement of said fork rod, which ignition system includes a battery, an ignition coil having a primary and secondary windings, said primary winding being connected at one terminal thereof with said battery through an ignition switch and said secondary winding being connected selectively to ignition plugs, and an ignition distributor having a first and second interruptors means, said first interruptor means being connected with the other terminal of said primary winding so as to provide normal ignition timings, said second interruptor means being connected in parallel with said first interruptor means to said primary winding through an ignition timing control switch means which is normally kept open and arranged to provide ignition timings retarded from the timings determined by said first interruptor means, said ignition timing control switch means comprising two stationary contacts connected respectively with said primary winding and said second interruptor means, a moving contact which is rigidly connected with an insulating moving member extending toward said fork rod and usually forced against the peripheral wall of said fork rod by a spring action whereby said moving contact is moved beyond said stationary contacts, said moving member being forced to protrude into said recess by a spring action as said fork rod is moved axially by said speed selector lever to permit said moving contact to abut to said stationary contacts for connecting said second interruptor means with said primary winding, said ignition timing control switch means being closed when the motor vehicle is driven under predetermined conditions, whereby the ignition timing is retarded under said conditions.