Automatic headlight dimmer apparatus

• US 5,086,253 A
• Filed: 10/15/1990
• Issued: 02/04/1992
• Est. Priority Date: 10/15/1990
• Status: Expired due to Fees

• Current Assignee: Louis N. Lawler
• Original Assignee: Louis N. Lawler
• Inventors: Lawler, Louis N.
• Primary Examiner(s): LaRoche, Eugene R.
• Assistant Examiner(s): YOO, DO H
• Time in patent office: 477 Days
• Field of Search: 315/82, 315/80, 315/83, 315/159, 315/154, 307/10.8
• US Class Current: 315/83
• CPC Class Codes: B60Q 1/1423 Automatic dimming circuits, i.e. switching between high beam and low beam due to change of ambient light or light level in road traffic
• CPC Class Codes: B60Q 2300/052 Switching delay, i.e. the beam is not switched or changed instantaneously upon occurrence of a condition change
• CPC Class Codes: B60Q 2300/42 oncoming vehicle

Abstract

An apparatus within a vehicle including a plurality of high beams in electrical communication with an automatic circuit to direct voltage to each associated high beam, wherein a photo-transistor is arranged in parallel circuitry to a relay coil and resistor, with the junction transistor arranged to interface between the first and the second parallel circuit, including the photo-transistor and adjustable resistor respectively. A modified detector circuit includes a second resistor in series with the resistor, and a third resistor in parallel relationship to the relay coil to effect a time delay in actuation of the high beam members of the vehicle. A third junction transistor is arranged in a third circuit parallel to the first and second circuit to direct current to the respective high beam for increased sensitivity relative to the incoming light source from a remote vehicle.

Claims

1. An automatic headlight dimmer switch comprising, in combination,

a light directional tube mounted to a vehicle, the directional tube including a beveled left side to permit light into the directional tube from an oncoming vehicle, and the directional tube including a photo-sensitive transistor mounted within the tube, the photo-sensitive transistor arranged in a first circuit loop parallel to a second circuit loop, the second circuit loop including a first adjustable potentiometer resistor in series with a relay coil, and

a first junction transistor coupled between the first circuit loop and the second circuit loop, and

a high beam voltage input line coupled to at least one high beam lamp mounted within the vehicle, and operative to direct voltage to the high beam lamp upon absence of light directed into the light directional tube upon actuation of the relay coil, and

a third circuit loop arranged parallel to the first and second circuit loop, with the third circuit loop including a second junction transistor at a junction between the first, second, and third circuit loops, and a second resistor in series with the first adjustable resistor, and a third resistor in parallel with the relay coil, and a capacitor in series with the third resistor to effect a time delay in actuation of the relay coil to permit complete passage of the oncoming vehicle.