GB2089080A

GB2089080A - Vehicle inadvertence alarms

Info

Publication number: GB2089080A
Application number: GB8039230A
Authority: GB
Original assignee: Individual
Current assignee: Individual
Priority date: 1980-12-08
Filing date: 1980-12-08
Publication date: 1982-06-16

Abstract

The invention relates to a device for giving a warning if the lights 3 of a vehicle are left on when the driver leaves the vehicle. A buzzer 6 is connected between the lighting circuit and the courtesy light switch 5 so that the buzzer will operate if the driver's door is opened while any of the lights of the vehicle are on. A diode 7 is included in a position such that no current can flow in the reverse direction from the courtesy light circuit through the buzzer to earth via the main lighting circuit of the vehicle. An additional blocking diode may be provided to prevent the buzzer being activated when the courtesy light circuit is completed via a manual or passenger door switch. A visual warning device may be provided in addition to or in place of the buzzer. <IMAGE>

Description

SPECIFICATION Improvements in or relating to vehicle warning devices The present invention relates to vehicle warning devices, and more particularly to devices for giving warning if any of the electrical circuits associated with a vehicle inadvertently is left switched on.

Conditions which call for the use of the lights as a vehicle during day time do not occur very often. As a result when such conditions do occur, a driver of a motor vehicle is apt to forget to switch off the lights of the vehicle either when driving conditions improve, or later when he leaves his vehicle. On his return the driver may well find that the battery of the vehicle is totally discharged.

It is an object of the present invention to provide a warning device which guards against the possibility of an electrical circuit associated with a vehicle inadvertently being left switched on when the driver leaves the vehicle.

According to the present invention there is provided a device for giving warning if an electrical circuit associated with a vehicle is left switched on when a driver of the vehicle leaves it, comprising an audible warning device one side of which is connected to a return path which forms part of the electrical system of the vehicle, a switch which is activated when the door on the driver's side of the vehicle is opened and the other side of which is connected to the said electrical circuit via a unidirectional element which is arranged to permit the passage of electric current from the said circuit to the warning device, but not vice versa.

The uni-directional element may be a separate device such as a diode or it may be incorporated into the warning device. The warning device may be audible, visual, or both.

The said electrical circuit may be the lighting circuit of the vehicle, and the said switch may be that which is usually provided to operate a light in the passenger compartment of the vehicle whenever the driver's door is opened and known as a "courtesy" switch. Most vehicles nowadays are provided with such lights and courtesy switches, but in addition there may be provided further courtesy switches which are operated when other doors of the vehicle are opened. Also, the interior light is usually provided with a switch. In normal practice, these switches are connected in parallel on the earthy side of the interior light. In circumstances where such additional switches are included there may be provided an additional uni-directional element arranged to prevent the passage of electric current through the warning device to earth via those switches.

The invention will now be described, by way of example, with reference to the accompanying drawings, in which, Figure is a circuit diagram of one embodiment of the invention, and Figure 2 is a circuit diagram of a second embodiment of the invention.

Referring to Figure 1, the lighting circuit 1 of a motor car is represented diagrammatically by a switch 2 and a number of lamps 3 wired in parallel. A separately energised interior light 4 is included in the live wire of a switch 5 which is arranged to connect the interior light 4 to earth when the driver's door of the car is opened, so as to provide so-called courtesy action of the interior light 4. Connected between the earthy side of the switch 2 and the live side of the switch 5 is a warning buzzer 6. A diode 7 is included in the lead 8 connecting the buzzer 6 to the lighting circuit 1 of the car. The diode 7 is so connected that it will allow electric current to flow from the lighting circuit 1 to the buzzer 6, but not vice versa.Thus, if the lights 3 are switched on and the driver's door is opened, the buzzer 6 is connected to earth and gives an audible warning that the lights are on, but if the switch 2 is open, then no current can flow from the interior light 4 through the buzzer 6 to earth via the lights 3, and so the buzzer 6 will not sound if the driver's door of the car is opened.

Figure 2 shows a circuit diagram of a more sophisticated arrangement in which both the passenger's door of the car and the interior light 4 have operating switches 21 and 22, respectively, which are wired in parallel with the switch 5. It can be seen that operation of either of the switches 21 and 22 will tend to cause the buzzer 6 to operate. This could well be a nuisance as passengers often get into and out of cars during the course of a journey. In order to prevent this, a blocking diode 23 is included to prevent current passing from the lighting circuit 1 through the buzzer 6 to earth via either of the switches 21 or 22.

If desired a visual warning device can be used in conjunction with the audible warning device or indeed, on its own.

CLAIMS (Filed 30 Nov. 1981) 1. Awarningdeviceforgivingwarning if an electrical circuit associated with a vehicle is left switched on when a driver of the vehicle leaves the vehicle, comprising an audible warning device one side of which is connected electrically to the said circuit via a uni-directional element which is arranged to permit the passage of electric current from the said circuit to the audible warning device but not vice versa and the other side of which is connected electrically to a return path which forms part of the electrical system of the vehicle via a switch which is arranged to be operated when a door of the vehicle intended for use by driver of the vehicle is opened.

2. A warning device according to claim 1 wherein the electrical system of the vehicle includes an interior light which is adapted to be operated either individually or when at least one of the doors of the vehicle is opened, and a unidirectional element is so positioned as to prevent any potential from being applied to the audible warning device via the interior light when it is in operation.

3. A warning device according to claim 2 wherein the unidirectional element which is so positioned as to prevent any potental being applied to the audible warning device via the interior light when it is in

**WARNING** end of DESC field may overlap start of CLMS **.

Claims

**WARNING** start of CLMS field may overlap end of DESC **. SPECIFICATION Improvements in or relating to vehicle warning devices The present invention relates to vehicle warning devices, and more particularly to devices for giving warning if any of the electrical circuits associated with a vehicle inadvertently is left switched on. Conditions which call for the use of the lights as a vehicle during day time do not occur very often. As a result when such conditions do occur, a driver of a motor vehicle is apt to forget to switch off the lights of the vehicle either when driving conditions improve, or later when he leaves his vehicle. On his return the driver may well find that the battery of the vehicle is totally discharged. It is an object of the present invention to provide a warning device which guards against the possibility of an electrical circuit associated with a vehicle inadvertently being left switched on when the driver leaves the vehicle. According to the present invention there is provided a device for giving warning if an electrical circuit associated with a vehicle is left switched on when a driver of the vehicle leaves it, comprising an audible warning device one side of which is connected to a return path which forms part of the electrical system of the vehicle, a switch which is activated when the door on the driver's side of the vehicle is opened and the other side of which is connected to the said electrical circuit via a unidirectional element which is arranged to permit the passage of electric current from the said circuit to the warning device, but not vice versa. The uni-directional element may be a separate device such as a diode or it may be incorporated into the warning device. The warning device may be audible, visual, or both. The said electrical circuit may be the lighting circuit of the vehicle, and the said switch may be that which is usually provided to operate a light in the passenger compartment of the vehicle whenever the driver's door is opened and known as a "courtesy" switch. Most vehicles nowadays are provided with such lights and courtesy switches, but in addition there may be provided further courtesy switches which are operated when other doors of the vehicle are opened. Also, the interior light is usually provided with a switch. In normal practice, these switches are connected in parallel on the earthy side of the interior light. In circumstances where such additional switches are included there may be provided an additional uni-directional element arranged to prevent the passage of electric current through the warning device to earth via those switches. The invention will now be described, by way of example, with reference to the accompanying drawings, in which, Figure is a circuit diagram of one embodiment of the invention, and Figure 2 is a circuit diagram of a second embodiment of the invention. Referring to Figure 1, the lighting circuit 1 of a motor car is represented diagrammatically by a switch 2 and a number of lamps 3 wired in parallel. A separately energised interior light 4 is included in the live wire of a switch 5 which is arranged to connect the interior light 4 to earth when the driver's door of the car is opened, so as to provide so-called courtesy action of the interior light 4. Connected between the earthy side of the switch 2 and the live side of the switch 5 is a warning buzzer 6. A diode 7 is included in the lead 8 connecting the buzzer 6 to the lighting circuit 1 of the car. The diode 7 is so connected that it will allow electric current to flow from the lighting circuit 1 to the buzzer 6, but not vice versa.Thus, if the lights 3 are switched on and the driver's door is opened, the buzzer 6 is connected to earth and gives an audible warning that the lights are on, but if the switch 2 is open, then no current can flow from the interior light 4 through the buzzer 6 to earth via the lights 3, and so the buzzer 6 will not sound if the driver's door of the car is opened. Figure 2 shows a circuit diagram of a more sophisticated arrangement in which both the passenger's door of the car and the interior light 4 have operating switches 21 and 22, respectively, which are wired in parallel with the switch 5. It can be seen that operation of either of the switches 21 and 22 will tend to cause the buzzer 6 to operate. This could well be a nuisance as passengers often get into and out of cars during the course of a journey. In order to prevent this, a blocking diode 23 is included to prevent current passing from the lighting circuit 1 through the buzzer 6 to earth via either of the switches 21 or 22. If desired a visual warning device can be used in conjunction with the audible warning device or indeed, on its own. CLAIMS (Filed 30 Nov. 1981)

1. Awarningdeviceforgivingwarning if an electrical circuit associated with a vehicle is left switched on when a driver of the vehicle leaves the vehicle, comprising an audible warning device one side of which is connected electrically to the said circuit via a uni-directional element which is arranged to permit the passage of electric current from the said circuit to the audible warning device but not vice versa and the other side of which is connected electrically to a return path which forms part of the electrical system of the vehicle via a switch which is arranged to be operated when a door of the vehicle intended for use by driver of the vehicle is opened.

3. A warning device according to claim 2 wherein the unidirectional element which is so positioned as to prevent any potental being applied to the audible warning device via the interior light when it is in operation also acts as the unidirectional element which is arranged to permit the passage of electric current from the said circuit to the audible warning device but not vice versa.

4. A warning device according to claim 1, claim 2 or claim 3 wherein there is included a visual warning device in conjunction with the audible warning device.

5. A warning device according to any preceding claim wherein the unidirectional element is a diode.

6. A warning device substantially as hereinbefore described with reference to the accompanying drawings.