GB2322103A

GB2322103A - Rapid de-mister for vehicle windscreens

Info

Publication number: GB2322103A
Application number: GB9703131A
Authority: GB
Inventors: Philip Alexander Paul Buckley; Andrew Buckley
Original assignee: Individual
Current assignee: Individual
Priority date: 1997-02-14
Filing date: 1997-02-14
Publication date: 1998-08-19
Also published as: GB9703131D0

Abstract

A rapid de-mister for vehicle windscreens comprises a heater 8a and a fan 8b permanently installed in a vehicle ventilation system. The power source is the vehicle itself, preferably the vehicle's electrical system which heats elements 5, hot air from which is then blown onto the windscreen by the fan. The fan is preferably additional to the main heating/ventilation fan. The fan may have a free wheeling clutch 9. Pressure control vents 2 may be provided before the fan. An automatic cut out switch 7 may be provided to switch off the rapid de-mister once the conventional heating system has reached operating temperature and a safety cut out 13 may be provided to prevent damage to the heating elements. The de-mister is preferably located as close to the windscreen as possible (16 figure 2).

Description

A RAPID DE-MISTER FOR VEHICLES WITH WINDSCREENS This invention relates to a rapid de-mister for vehicles with windscreens.

In cold weather, when entering a cold vehicle; very often the windscreen is fogged or quickly becomes fogged. Conventional methods involve the heating of a small heat exchanger usually housed in the vehicles ventilation distributor box. This requires the vehicles engine coolant to attain a temperature suitable for effective de-misting This invention comprises of heating elements and optional fan assistance situated in a tube which may be inserted into the vehicles windscreen ventilation duct, below the windscreen ventilation diffuser. The unit is wired into the vehicles electrical system. The fan blows cold air over the electrically elements, heating the air sufficiently to rapidly de-mist the windscreen.

A specific embodiment of the invention will now be described by way of example with reference to the accompanying drawings in which: Figure 1 shows a general diagram of the unit and it's components housed in the casing.

Figure 2 shows the location of the rapid de-misting unit within a vehicles ventilation system.

Figure 3 shows a suitable wiring circuit diagram for the rapid de-mister and it's integration into the vehicles electrical system.

Referring to figure 1, the fan assembly 1, 2, 3, 9, 11 is required if the vehicles main ventilation system does not supply an adequate flow rate of air. Spring 1 loaded valves 2 prevent the depressurisation of the vehicles main ventilation system when the fan is running.

The housing consists of two sections, 8a and 8b. Heating elements 5 are situated on a suitable temperature resistant and electrical insulating material 6, which is attached to heating element housing 8a. This assembly is mounted to the air diffuser and motor mounting 4.

The pipe joint 10 allows the fan components 3, 9 and 11 to be removed. The fan blades 3 are attached to a freewheeling clutch 9 and powered by an electric motor 11, forcing air past the heating elements 5. A temperature dependant switch 13 ensures that the elements do not overheat, while heat reflecting material 12 prevents overheating of the heating element housing 8a housing..

The unit shown in Fig 1 is installed into the vehicles main ventilation system as shown in Fig 2. Points 14 and 15 represent the footwell and side window air outlets respectively on the vehicle. The de-mister units 16 are located as close to the windscreen duct diffusers 17 as possible.

When the engine coolant temperature rises to a level capable of maintaining a clear windscreen, the temperature control switch 7 opens the circuit shown in Fig 3 and shuts off the power supply to the heater coils 5 and bulb 18. From the power supply 20, the master switch 19 must be closed in order for the system to work and switch 21 must be closed along with switch 19 in order for the heater coils to be powered, this is to prevent the overheating of the coils.

Claims

1. A rapid de-mister comprising of heater coils and fan unit to be permanently installed in a vehicles ventilation system.

2. A rapid de-mister as claimed in claim 1 maybe separated into the heating section and the fan section..

3. A rapid de-mister as claimed in claim 1 uses heat derived from electrical energy, and accelerated air flow to de-mist the windscreen.

4. A rapid de-mister as claimed in claim 1 is permanently wired into the vehicles electrical system.

5. A rapid de-mister as claimed in claim 1, has a free wheeling clutch mounted to the fan blades to allow a free flow of air to pass when the motor is switched off.

6. A rapid de-mister as claimed in claim 5 has pressure control vents on the inlet before the fan, wherein the valves open as a result of a pressure drop in the windscreen ventilation duct.

7. A Rapid de-mister as claimed in claim 1 is provided with an electrical control system to prevent overheating.

8. A rapid de-mister as claimed in claim 1 has heat reflecting material protection inside the main housing.

9. A rapid de-mister as claimed in claim 1 assists the vehicles ability to de-mist the windscreen when the engine coolant is cold.

10. A rapid de-mister for vehicles substantially as described herein with reference to Figures 1-3