Sequential flash type directional signal device for automobiles

Claim 1

A sequential flasher type directional signal device for automobiles comprising a right and left turn signal indicator, each consisting of a plurality of lamps in a row and a control circuit means connected in series with a power source and said plurality of lamps for turning said lamps on sequentially one after another, turning them all off at the same time, and reinitiating the cycle to indicate the direction of right and left turns respectively; said control means comprises; a plurality of time delay means, one less than the number of said plurality of lamps for a given turn direction, one time delay means is connected in parallel with each lamp, except the last lamp in the sequence for delaying the activation of the next lamp in said sequence in response to the activation of the previous lamp in the sequence; a plurality of switch means, one in series with each lamp''s power input for activating a lamp in response to the preceding lamp''s time delay means; a cycle reset means connected between said power source and the lamp''s power input for turning off all the lamps at the same time and restarting the cycle upon the activation of the last lamp; said cycle reset means comprises a series circuit of a first resistor and a capacitor connected between the last lamp in said sequence and a first switching transistor, a bias resistor connected between the base of said first transistor and the plus side of a power source, the emitter of said first transistor being connected to said plus side of said power source, a relay coil connected between the collector of said first transistor and the minus side of said power source, said base of said first transistor is connected to the collector of a second switching transistor, a base resistor connected between the base of said second transistor and said last lamp in said sequence, an emitter resistor connected between the emitter of said second transistor and said minus side of said power source, and a normally-closed relay contact, which is opened upon energization of said relay coil, is in series between said power source and all of said lamps'' power inputs, whereby said capacitor which is initially charged through said bias resistor and holds said first transistor off, is discharged when the last lamp of said sequence is lit and said second transistor conducts and allows said first transistor to conduct to activate said relay to disconnect said power source from said lamps'' power inputs.