GB2084413A - Vehicle indicator device - Google Patents

Abstract

A vehicle indicator device for use on a motorcycle provides a fixed number of flashes when operated, and then automatically cancels itself. This is achieved by means of a pulse generating circuit composed of a Schmitt trigger (IC2c), a resistor (R4) and a capacitor (C3). A resettable counter (IC1) counts the pulses produced by the pulse generating circuit whenever the user operates the indicator device. While the counter (IC1) is counting, power is supplied to the left or right indicator lamps. Once the counter (IC1) has counted a predetermined number of pulses power ceases to be supplied to the indicator lamps. A hazard warning option is also incorporated by use of which both right and left indicator lamps are operated independently of the state of the counter. <IMAGE>

Description

SPECIFICATION Vehicle indicator device This invention relates to a vehicle indicator device and is particularly, though not exclusively, concerned with an indicator device for use on a motorcycle. The object of the invention is to provide an indicator device which provides a fixed number of flashes when the device is operated and then automatically cancels itself. In a preferred embodiment, a hazard warning function is also incorporated, operation of which causes all the indicator lights to flash simultaneously.

Most known motorcycle indicator devices use a purely mechanical system which is switched on and off manually by the rider. More recently, an electronic system has been introduced which automatically cancels the indicators after a period of time, but the period of time concerned is inversely proportional to the speed of the motorcycle. Accordingly, when the motorcycle is travelling very quickly the indicator is liable to be cancelled far too soon, whereas when travelling slowly, for example in the city, the indicator is liable to continue to operate after it should have cancelled.

According to the present invention there is provided a vehicle indicator device comprising at least one left and at least one right indicator lamp; a pulse generating circuit operable to produce a succession of pulses at a fixed pulse frequency; a resettable counter arranged to count the said pulses; and indicator selection means for enabling power to be supplied to the left or right indicator lamps until the counter has counted a predetermined number of pulses.

Figures 1 and 2 of the accompanying drawings show two embodiments of the invention.

The embodiment illustrated in Figure 1 uses a conventional 1 2 volt supply and an indicator switch SW1 shown in the drawings in its neutral position. When power is applied through diode D1 or D2, a reset pulse appears at pin 2 of the counter IC1, thereby resetting the counter. The reset pulse is generated by the circuit which comprises capacitance C1 and resistor R2. At the same time power is supplied to a Schmitt trigger circuit composed of integrated circuit IC2c, resistor R4 and capacitance C3. The Schmitt trigger circuit thereupon commences to oscillate and feeds pulses to pin 1 of the counter IC1. The frequency of the pulses is determined by the values of C3 and R4.On alternate pulses the pin 11 of the counter goes high (logic 1) causing the circuit composed of lC2a, IC2b, IC2c, lC2f, R5 and R6 to oscillate, which in turn turns on the transistors Q1 and Q2. With the transistors Q1 and Q2 turned on current can pass through resistors R7 and R8 to the bases of the power transistors Q3 and Q4, one of which will then provide a current path to the left or right indicator lamp, according to the position of the switch S1.

The counter IC1 is a 7 stage ripple counter, and pin 3 represents the 1 6th count. When the 1 6th count is reached the pin 3 goes high (logic 1) which in turn causes pin 5 of lC2c to go high via a diode D5 and a normally closed switch SW2. The change in state from logic 0 to logic 1 at pin 5 causes the Schmitt trigger circuit to cease oscillating, thus halting the count of the counter IC1.The counter will remain in the state which it has reached until it is reset by operation of switch SW1.

Various additional points may be noted regarding the circuit shown in the drawing.

Resistance R3 and capacitance C2 provide stability to the circuit. Resistance R1 and Zener diode ZD1 prevent spurious voltages from damaging the integrated circuits.

The illustrated circuit also includes a hazard flashing arrangement. For this purpose, diodes D3 and D4 are connected to the switch SW2, and when switch SW2 is switched on power is applied to both diodes D3 and D4. The other side of the switch open-circuits the diode D5, thus preventing the output of pin 3 of counter IC1 from stopping the generation of clock pulses once the 1 6th pulse has been reached. Hence, the counter IC1 continued to count until such time as the switch SW2 is returned to its neutral position.

Various modifications may be made to the illustrated circuit. For example, the transistors Q3, Q4 may be replaced by relays.

The major part of the illustrated circuit can be encapsulated in a resin block. The dashed line in the drawing indicates the division between the encapsulated portion, to the left of the line, and the non-encapsulated portion, to the right of the line. The circuit can be mounted at any convenient part of the body work of a motorcycle, for example on the headlamp cowling. The switch SW1 can be an existing indicator switch provided on the motorcycle for operating the indicator lamps, with the switch SW2 being an additional switch. If desired, however, the whole of the illustrated circuit, except for the power supply and the indicator lamps, could form an integral unit.

The embodiment shown in Figure 1 uses a mechanical switch SW1, movable between a position in which it causes the production of a series of left-indicating flashes and a position in which it causes the production of a series of rightindicating flashes. By contrast, the embodiment of Figure 2, uses a pair of push button, momentary actuation of one of which produces the leftindicating flashes, and momentary actuation of the other of which produces the right-indicating flashes. In the circuit of Figure 2, components which are analogous, or substantially analogous, to components in Figure 1 are given the same reference numerals. Thus, a counter IC1 is used for the purpose of counting pulses fed by a Schmitt trigger circuit composed of integrated circuits IC2c, resistor R4 and capacitance C3.The principal way in which the circuit of Figure 2 differs from that of Figure 1 is the way in which the counter IC1 is operated, and this will now be described in more detail.

A sequence of right-indicating pulses is produced by momentary actuation of push button PBl . This applies a momentary pulse through a resistor network R9, R 10 to flip flop 1, which forms one half of the dual flip flop device 1C3. The pulse is applied to set pin 6, thereby causing its Q output 1 to go high. A diode D6 is connected between pin 6 and the reset pin 10 of flip flop 2 which forms the other half of the flip flop device IC3. Accordingly, the momentary pulse is simultaneously applied to pin 10 to reset flip flop 2. Push button PB2 is used to produce a sequence of left-indicating pulses.If PB2 is actuated instead of PB1 a momentary pulse is applied through the resistor network R11, R12 to the set pin 8 of flip flop 2, and is applied through diode D7 to the reset pin 4 of flip flop 1. In this case the Q output 13 of the flip flop 2 goes high. If either of the push buttons PB1 and PB2 is actuated accidentally, or if it is desired to cease the flash sequence before the predetermined number of flashes has been produced, this can be done by actuation of the push button PB3.

This applies a momentary pulse through the resistor network R13, R1 4 and the diodes D8 and D9 to both the reset pins 4 and 10.

When either pin 1 or pin 1 3 goes high a current is caused to pass through diode Dl 2 or D13 and resistor R1 5 turning on transistor Q5. This allows the 12 volt supply to pass through pin 14 of the counter IC1 via resistor R1 6. The counter then operates to produce a sequence of pulses at pin 11, in the same way as described above with reference to Figure 1.

Considering now the case where PB1 has been actuated, the high at pin 1 of the flip flop device IC3 is applied to point A of a switching network.

The high is applied via resistor R20 to turn on transistor Q1 . This in turn allows the pulse frequency available at pin 11 of counter IC1 to pass through the Schmitt oscillator circuit IC2a and IC2b and thence through transistor Q1 and resistor R21 to turn on transistor Q7. The result of this is that transistor Q3 is turned on so permitting power to be applied to the right-indicating lamps, which are indicated by the legend LOAD RIGHT.

If push button PB2 is actuated instead of push button PB1 an exactly comparable sequence of events takes place involving the switching on of transistors Q2, Q6 and Q4, and a consequent application of power to the left-indicating lamps, indicated by LOAD LEFT.

When the preset number of pulses has been counted by counter IC1 the flip flop device IC3 is reset by a reset pulse which is produced at pin 3 of counter IC1 and passes to the flip flop device IC3 via diodes D10 and D1 1.

Figure 2 shows the switch SW2 with which the circuit is provided. Normally the contact path between terminals M and N is closed, and in this position of switch SW1 the circuit of Figure 2 operates as described above. The path between terminals X and Y is closed. If, however, the switch is moved to its alternative position, in which the contact between M and N is open and the contact between X and Y is closed the circuit will operate in a hazard warning mode. It will be seen that terminals X and Y are located at the ends of resistors R18 and R21 in the switching circuit.

Closing the contact between these two terminals has the effect that whichever of the push buttons PB1 and PB2 is actuated power will be applied both to LOAD LEFT and to LOAD RIGHT. Since the contacts between M and N is open the reset pulse produced at pin 3 is ineffective and power will continue to be applied to LOAD LEFT and LOAD RIGHT, with consequent flashing of all the indicator lamps, until such time as the flashing is cancelled by actuation of push button PB3.

Finally, for completeness, it should be mentioned that power is supplied to IC2 and IC3 via their pins 14 (not shown) as indicated by the legend in Figure 2.

Claims (9)

1. A vehicle indicator device comprising at least one left and at least one right indicator lamp; a pulse generating circuit operable to produce a succession of pulses at a fixed pulse frequency; a resettable counter arranged to count the said pulses; an indicator selection means for enabling power to be supplied to the left or right indicator lamps until the counter has counted a predetermined number of pulses.

2. Advice according to claim 1, wherein the indicator selection means comprises a switch movable between a first, left-indicating position, a second, right-indicating position, and a third, neutral, position.

3. A device according to claim 1 , wherein the indicator selection means comprises a first, leftindicating, selection means, a second, rightindicating selection means, and a latching circuit operable upon actuation of the first or second selection means to enable power to be supplied to the left or right indicator lamps.

4. A device according to claim 3, wherein the latching means comprises first and second flip flops, the first flip flop producing an output in response to receipt of an input pulse from the first selection means, and the second flip flop producing an output in response to receipt of an input pulse from the second selection means.

5. A device as claimed in claim 3 or 4, comprising a third selection means, actuation of which cancels latching produced by either of the first and second selection means.

6. A device as claimed in any one of claims 3 to 5, wherein the selection means are push buttons.

7. A device according to any preceding claim, which comprises a hazard warning selector, actuation of which overrides operation of the indicator selection means so as to enable power to be supplied to both the left and right indicator lamps independently of the operation of the counter.

8. A device according to any preceding claim, wherein the pulse generating circuit comprises a Schmitt trigger.

9. A vehicle indicator device substantially as herein described with reference to Figure 1 or Figure 2 of the accompanying drawings.