GB1587035A

GB1587035A - Switching arrangement for a combined vehicle window and headlamp cleaning installation

Info

Publication number: GB1587035A
Application number: GB16923/78A
Authority: GB
Original assignee: Bayerische Motoren Werke AG
Current assignee: Bayerische Motoren Werke AG
Priority date: 1977-04-29
Filing date: 1978-04-28
Publication date: 1981-03-25
Also published as: DE2719183B1; DE2719183C2; FR2388702A1; SE419727B; SE7804931L; FR2388702B1

Description

(54) SWITCHING ARRANGEMENT FOR A COMBINED VEHICLE WINDOW AND HEADLAMP CLEANING INSTALLATION (71) We, BAYERISCHE MOTOREN WERKE AKTIENGESELLSCHAFT, a Germany Body Corporate, of BMW-Haus, Petuelring 130, 8 München 40, German Federal Republic, do hereby declare the invention for which we pray that a patent may be granted to us, and the method by which it is to be performed, to be particularly described in and by the following statement: This invention relates to a switching arrangement for a window and headlamp cleaning installation in a motor vehicle, comprising a common wash fluid container and a level-actuated switch.

Such a switching arrangement is present in vehicle type BMW 630 CS manufactured by us. If the driver wishes to find out whether the level of fluid in the common wash fluid container is satisfactory, he operates a key-push switch. If the level is too low, the level-actuated switch will have closed a break in an electrical conductor which, when the key-push switch is operated, will cause a warning light to light up, indicating that the container should be replenished with wash fluid. Window and headlamp cleaning appliances can be operated jointly until the wash fluid has been completely used up.

An aim of the invention is the provision of a switching arrangement of the type specified in the opening paragraph, which, using simple switching techniques, makes possible a more prolonged operation of a single one of the cleaning appliances by comparison to the joint operation of the combined window and headlamp cleaning installation.

In accordance with the invention, the level-actuated switch is arranged to inhibit supply of fluid to the window or to the headlamp when the level of fluid in the container falls to a predetermined level.

The switch may have a part which moves with the fluid level.

For a cleaning installation comprising one electrically operated appliance for cleaning a window and one for cleaning a headlamp, the switch may be arranged to switch off one of these appliances, for example the one for cleaning a headlamp, when the fluid level falls to the said predetermined level. The residual amount of wash fluid in the container when the level-actuated switch is switched is then available entirely for the benefit of the other cleaning appliance. The switch may also cause a warning light to be switched on when the fluid level falls to the said predetermined level.

It is known to arrange the intake port of a wash pump for the window cleaning appliance in the common wash fluid container at a higher level than the corresponding opening for the headlamp cleaning installation (see German Auslegeschrift DT-AS 25 19 148), and in this way to lead residual wash fluid exclusively to the headlamp cleaning appliance. However, with this arrangement, the wash pump and wiper motor for the window cleaning appliance may continue operating. This "dry running" of the wash pump and of the window wiper can lead to their being damaged. If the level-actuated switch switches off the window cleaning appliance, using a switching arrangement in accordance with the invention, then damaging of this appliance due to a lack of wash fluid is made less likely.

As an alternative, the level-actuated switch may switch off only the headlamp cleaning appliance. The residual amount of wash fluid is then available for the cleaning appliance that is of greater importance, namely the appliance for the window to give the driver clear vision.

In both embodiments of the invention making the assumption that the window cleaning appliance and the headlamp cleaning appliance use an equal amount of wash fluid per washing cycle, the switched-on cleaning appliance can be operated for twice as lofig with the residual wash liquid as is possible with joint operation of the window and headlamp cleaning appliances.

If the level-actuated switch switches a warning light on directly, then the user of the vehicle is automatically shown that wash fluid needs to be replenished and that one of the two cleaning appliances can no longer be operated when the predetermined low level of wash fluid is reached.

The invention also relates to a motor vehicle having window cleaning means and headlamp cleaning means which share a common reservoir for containing cleaning liquid used during cleaning, operation of both said cleaning means being controlled by an electric circuit which includes an operating switch and also a level-actuated switch, the latter switch changing its switching state from a first switching to a second switching state when the liquid level in the reservoir falls below a predetermined minimum, the operating switch serving when operated (provided that the level-actuated switch is in its said first switching state, and provided also that the electric circuit is suitably energised, for example by the closing of an ignition switch and the closing of a headlamp operating switch) to operate at least respective cleaning liquid supply motors of the two cleaning means, the level-actuated switch when switching to its second switching state causing operation of the operating switch to operate the liquid supply motor of one the cleaning means only.

A preferred embodiment of the invention is described in greater detail by way of an example with reference to the accompanying drawing, in which the single figure shows a switching arrangement for a window and headlamp cleaning installation which switches off the headlmap cleaning appliance when only a certain residual amount of wash liquid remains in a wash liquid container.

In a switching arrangement in the electrical circuit of a motor vehicle there are arranged a window-cleaning appliance 1 and a headlamp cleaning appliance 2. The cleaning appliances 1 and 2 each have a plurality of motors, for instance for the window wipers and window wash pump, and the headlamp wipers and headlamp wash pump, of which respective motors 3 and 4 are shown in the Figure.

The cleaning appliances 1 and 2 can be switched on by a common wash switch 5 which actuates respective switching transistors 8 and 9 at their bases via resistances 6 and 7. In their input circuit the switching transistors 8 and 9 have respective coils 10 and 11 of respective relays, whose contacts 10' and 11' are connected in series with the motors 3 and 4 respectively.

The current supply to the cleaning appliances 1 and 2 is via an ignition switch 15 by means of the ignition current circuit.

Furthermore, a switch 12 for the headlamp cleaning appliance 2 that is operated jointly with the not-illustrated warning light switch is located in the input circuit of the switching transistor 9.

A switch contact 13' forming part of a level-actuated switch 12 contained in a common wash fluid container 14 for the cleaning appliances 1 and 2 lies in parallel with the base emitter section of the switching transistor 9. Below a given minimum level 16 in the wash liquid container 14 the switch contact 13' is closed. Further, a pilot light 17 is connected in series with the switching contact 13'.

With the ignition current circuit closed and the vehicle illumination switched on, that is with switches 15 and 12 closed, the window and the headlamp cleaning appliances 1 and 2 are switched on when the wash switch 5 is actuated, provided that the level in the wash liquid container 14 is above the minimum level 16.

Below the minimum level 16 the levelactuated switch 13 connects the base of the switching transistor 9 to ground. The switching transistor 9 is therefore switched off, and will remain switched off when the wash switch 5 is actuated. As a consequence, the headlamp cleaning appliance 2, which is not as important as the window cleaning appliance which is needed to ensure the vehicle driver's clear vision, is switched off and no longer uses up wash fluid. The residual amount of wash fluid remaining in the wash fluid container 14 is available exclusively for the window cleaning appliance 1 for a considerable period of time.

The window cleaning appliance 1 can still be switched on and off by means of the wash switch 5.

The necessity for the user of the vehicle to replenish wash fluid, so that the headlamp cleaning appliance 2 can again be capable of being operated, is indicated by the pilot or warning light 17 that is switched on by the switch contact 13' below the minimum level 16.

WHAT WE CLAIM IS: 1. A switching arrangement for a combined window and headlamp cleaning installation in a motor vehicle, comprising a common wash fluid container and a levelactuated switch arranged to inhibit supply of fluid to the window or to the headlamp when the level of fluid in the container falls to a predetermined level.

2. A switching arrangement according to claim 1, in which the level-actuated switch has a part which moves with the fluid level.

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

Claims

**WARNING** start of CLMS field may overlap end of DESC **. cleaning appliance can be operated for twice as lofig with the residual wash liquid as is possible with joint operation of the window and headlamp cleaning appliances. If the level-actuated switch switches a warning light on directly, then the user of the vehicle is automatically shown that wash fluid needs to be replenished and that one of the two cleaning appliances can no longer be operated when the predetermined low level of wash fluid is reached. The invention also relates to a motor vehicle having window cleaning means and headlamp cleaning means which share a common reservoir for containing cleaning liquid used during cleaning, operation of both said cleaning means being controlled by an electric circuit which includes an operating switch and also a level-actuated switch, the latter switch changing its switching state from a first switching to a second switching state when the liquid level in the reservoir falls below a predetermined minimum, the operating switch serving when operated (provided that the level-actuated switch is in its said first switching state, and provided also that the electric circuit is suitably energised, for example by the closing of an ignition switch and the closing of a headlamp operating switch) to operate at least respective cleaning liquid supply motors of the two cleaning means, the level-actuated switch when switching to its second switching state causing operation of the operating switch to operate the liquid supply motor of one the cleaning means only. A preferred embodiment of the invention is described in greater detail by way of an example with reference to the accompanying drawing, in which the single figure shows a switching arrangement for a window and headlamp cleaning installation which switches off the headlmap cleaning appliance when only a certain residual amount of wash liquid remains in a wash liquid container. In a switching arrangement in the electrical circuit of a motor vehicle there are arranged a window-cleaning appliance 1 and a headlamp cleaning appliance 2. The cleaning appliances 1 and 2 each have a plurality of motors, for instance for the window wipers and window wash pump, and the headlamp wipers and headlamp wash pump, of which respective motors 3 and 4 are shown in the Figure. The cleaning appliances 1 and 2 can be switched on by a common wash switch 5 which actuates respective switching transistors 8 and 9 at their bases via resistances 6 and 7. In their input circuit the switching transistors 8 and 9 have respective coils 10 and 11 of respective relays, whose contacts 10' and 11' are connected in series with the motors 3 and 4 respectively. The current supply to the cleaning appliances 1 and 2 is via an ignition switch 15 by means of the ignition current circuit. Furthermore, a switch 12 for the headlamp cleaning appliance 2 that is operated jointly with the not-illustrated warning light switch is located in the input circuit of the switching transistor 9. A switch contact 13' forming part of a level-actuated switch 12 contained in a common wash fluid container 14 for the cleaning appliances 1 and 2 lies in parallel with the base emitter section of the switching transistor 9. Below a given minimum level 16 in the wash liquid container 14 the switch contact 13' is closed. Further, a pilot light 17 is connected in series with the switching contact 13'. With the ignition current circuit closed and the vehicle illumination switched on, that is with switches 15 and 12 closed, the window and the headlamp cleaning appliances 1 and 2 are switched on when the wash switch 5 is actuated, provided that the level in the wash liquid container 14 is above the minimum level 16. Below the minimum level 16 the levelactuated switch 13 connects the base of the switching transistor 9 to ground. The switching transistor 9 is therefore switched off, and will remain switched off when the wash switch 5 is actuated. As a consequence, the headlamp cleaning appliance 2, which is not as important as the window cleaning appliance which is needed to ensure the vehicle driver's clear vision, is switched off and no longer uses up wash fluid. The residual amount of wash fluid remaining in the wash fluid container 14 is available exclusively for the window cleaning appliance 1 for a considerable period of time. The window cleaning appliance 1 can still be switched on and off by means of the wash switch 5. The necessity for the user of the vehicle to replenish wash fluid, so that the headlamp cleaning appliance 2 can again be capable of being operated, is indicated by the pilot or warning light 17 that is switched on by the switch contact 13' below the minimum level 16. WHAT WE CLAIM IS:

1. A switching arrangement for a combined window and headlamp cleaning installation in a motor vehicle, comprising a common wash fluid container and a levelactuated switch arranged to inhibit supply of fluid to the window or to the headlamp when the level of fluid in the container falls to a predetermined level.

3. A switching arrangement according

to claim 1 or claim 2, in which the cleaning installation comprise an electrically operated appliance for cleaning a window of a vehicle and an electrically operated appliance for cleaning a headlamp of a vehicle, the level-actuated switch being arranged to switch off one of the appliances when the level of the fluid in the container falls to the said predetermined level.

4. A switching arrangement according to claim 3, in which the level-actuated switch is arranged to switch off the headlamp cleaning appliance.

5. A switching arrangement according to claim 3 or 4, in which the level-actuated switch is arranged to switch on a pilot light at the same time as it switches off the said one of the appliances.

6. A motor vehicle having window cleaning means and headlamp cleaning means which share a common reservoir for containing cleaning liquid used during cleaning, operation of both said cleaning means being controlled by an electric circuit which includes an operating switch and also a level-actuated switch, the latter switch changing its switching state from a first switching state to a second switching state when the liquid level in the reservoir falls below a predetermined minimum, the operating switch serving when operated (provided that the level-actuated switch is in its said first switching state, and provided also that the electric circuit is suitably energised, for example by the closing of an ignition switch and the closing of a headlamp operating switch) to operate at least respective cleaning liquid supply motors of the two cleaning means, the level-actuated switch when switching to its second switching state causing operation of the operating switch to operate the liquid supply motor of one of the cleaning means only.

7. A motor vehicle according to claim 6, in which each said cleaning means includes, in addition to the said respective cleaning liquid supply motors, respective wiper operating motors, the electric circuit being such that when the liquid supply motor of each cleaning means is energised the wiper operating motor of that cleaning means is also energised.

8. A motor vehicle according to claim 4 or claim 5, in which the level-actuated switch is arranged to inhibit operation of the headlamp cleaning means when it is in its second state.

9. A motor vehicle according to any of claims 4 to 6, in which the level-actuated switch is so arranged that, when it is in its second state, it prevents a switching transistor of the circuit from being rendered conductive.

10. A motor vehicle according to any of claims 4 to 7, in which the level-actuated switch is arranged to switch on an indicating lamp when it is in its second switching state.

11. A motor vehicle having window cleaning means and headlamp switching means substantially as described herein with reference to the accompanying drawing.

12. For installation in a motor vehicle having window cleaning means and headlamp cleaning means, an electrical circuit substantially as described herein with reference to the accompanying drawing.