Communications: electrical – Land vehicle alarms or indicators – External signal light system
Patent
1998-08-20
2000-03-28
Lee, Benjamin C.
Communications: electrical
Land vehicle alarms or indicators
External signal light system
340476, 340477, 340478, 340465, 340526, 340527, B60Q 134
Patent
active
060437405
DESCRIPTION:
BRIEF SUMMARY
This invention relates to apparatus for giving and controlling vehicle signals, such as vehicle U-turn signals.
Most vehicles are equipped generally with turn signals commonly referred to as left and right turn indicators. Using such turn signals to indicate the intention of a driver to make a U-turn is inconvenient in operation and ambiguous in meaning, which can result in an increase in the frequency of accidents.
The invention seeks to mitigate problems such as this.
According to the invention there is provided a vehicle signalling system comprising a main indicator, an activating device, a timing device for measuring the intervals during which the activating device is not activated and means responsive to the activating device and to the timing device to activate the main indicator when the measured interval is less than a threshold value.
With fewer parts, eliminating extra switches, brackets, and redundant activation operations, apparatus embodying the invention can use the on-off-on wording state of an existing turn signal as the input.
The U-turn indicator may comprise an array of LEDs which makes a loop circuit with an arrow.
The invention will further be described by way of example with reference to the accompanying drawings, in which:
FIG. 1 is a control circuit diagram of apparatus embodying the invention;
FIGS. 2a-2g are wave forms of the control circuit of FIG. 1;
FIG. 3 is a schematic illustration of a first U-turn indicator for use in apparatus embodying the invention; and
FIG. 4 is a schematic illustration of a second U-turn indicator for use in apparatus embodying the invention.
In this embodiment the turn display comprises a plurality of LEDs 1, activated by a battery B1 through normally open contacts for a relay. The relay coil is activated by a battery B2 through a switching transistor 8550.
The vehicle has a turn indicator control (not shown) which causes a train of pulses to be supplied through a rectifier consisting of diodes D1 and D2 in series and a resistor RS return to earth. The pulse train is applied through respective diodes D4 and D5 to integrators I1 (C1 R1) and I2 (C2 R2), the time constant of I1 being less than that of I2. The output of I1 is applied through two inverters N2 and N3 in series to the clock input of a counter UL; the output of the integrator I2 is applied through a single inverter N1 to the reset input of the counter UL. The counter has outputs Q1, Q2, Q3 etc., and the outputs Q2 and Q3 are applied to respective inputs of a NOR gate through an inverter N4 to one input of a NAND. The rectified pulse train is applied directly to the other input of the NAND, whose output is connected to the base of switching transistor 8550 through a resister R4.
The effect of this circuit is that the NAND gates the rectified pulse train being applied to the switching transistor 8550 according to the state of the counter UL. FIG. 2 shows waveforms at different points in the circuit. Waveform (a) shows a first pulse train of two pulses followed by a short delay, less than 3 seconds, followed by a second pulse train of four pulses, followed by a long delay. When the pulse train starts, the rectified pulses charge up the integrators, whose outputs are then high. When the train stops, the outputs decay according to their time constants (waveforms (b) and (c)), so that after a first time the clock input will be changed from high to low (waveform (d)) and after a second longer time the reset input will be changed from low to high (waveform (e)) provided that no further pulse train has started. The outputs start to decay after the pulse train stops, so the integrators are measuring the time during which the twin indicator control is not activated. When a second pulse train starts the integrators will again charge up.
Considering first the case where the second train starts after both integrator outputs have dropped to the level which causes their output inverter to change state, as shown at the right hand ends of the waveforms, the reset input of the counter will have been activated a
REFERENCES:
patent: 4387361 (1983-06-01), Reed
patent: 4994786 (1991-02-01), Schaffer
patent: 5003289 (1991-03-01), Roman
patent: 5086289 (1992-02-01), Sullivan et al.
patent: 5281950 (1994-01-01), Le
patent: 5432500 (1995-07-01), Scripps
Ackerman Stephen B.
Lee Benjamin C.
Saile George O.
LandOfFree
Vehicle signalling apparatus does not yet have a rating. At this time, there are no reviews or comments for this patent.
If you have personal experience with Vehicle signalling apparatus, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Vehicle signalling apparatus will most certainly appreciate the feedback.
Profile ID: LFUS-PAI-O-1329583