GB2339306A

GB2339306A - Control of windscreen wipers on a motor vehicle

Info

Publication number: GB2339306A
Application number: GB9814441A
Authority: GB
Inventors: David Bowskill
Original assignee: MG Rover Group Ltd
Current assignee: MG Rover Group Ltd
Priority date: 1998-07-04
Filing date: 1998-07-04
Publication date: 2000-01-19
Anticipated expiration: 2018-07-04
Also published as: GB9814441D0; GB2339306B

Description

2339306 A Vehicle This invention relates to vehicles and in particular to

a vehicle including a wiper system.

It is known to provide a vehicle with a front windscreen and a rear windscreen and to provide a front windscreen wiper and a rear windscreen wiper. It is common practice to provide a number of wiping modes for the front windscreen wiper in each of which the front windscreen is wiped at a different rate. It is a problem with some known prior art systems that the rear windscreen is not sufficiently wiped during, for example. periods of exceptional rainfall such as typhoons.

It is an object of this invention to provide an improved vehicle.

According to the invention there is provided a vehicle including a first wiper means arranged in use to selectively wipe a first window in one of at least two modes and a second wiper means arranged in use to selectively wipe a second window in a predetermined manner, wherein the second wiper means is arranged to automatically alter the manner in which it wipes the second window in response to an alteration in the mode selected by the first wiper means for wiping the first window.

The first mode may comprise a first wipe rate and the second mode may comprise a second wipe rate of increased frequency, wherein the alteration to the manner in which the second wiper means wipes the second window comprises an automatic increase in the frequency of its own wipe rate when 5 the first wiper means is arranged to operate in the second mode.

Each of the wiper means may comprise a respective wiper selectiOll switch, wherein the alteration to the manner in which the second wiper means, when selected, wipes the second window is made automatically when the first wiper selection switch is moved into a position in which it selects the second mode of the first wiper means.

The second wiping means may be arranged in its unaltered condition to wipe the second window at a rate which includes an intermittent wipe phase. The alteration to'the manner in which the second wiper means wipes the second window may comprise a change from the intermittent wipe phase to a constant wipe phase. The wiping rate of the second wiper means during said constant wipe phase may be of a higher frequency than its wipe rate during its intermittent wipe phase.

The first window may comprise a front windscreen of the vehicle and the second window may comprise a rear windscreen of the vehicle.

The invention further provides a wiper system for a vehicle according to the invention and also provides a controller for such a wiper system, wherein the controller is programmable to control said first and second wiper means.

The invention will now be described by way of example with reference to the accompanying drawing, in which; Figure I is a schematic diagram of a vehicle according to the invent-ion.

Referring to the figure, a vehicle 10 comprises a front wiper motor 12 which is arranged to oscillate a front wiper assembly 14 across a front windscreen 16 in order to clear the windscreen 16 of, for example, rainfall. The vehicle 10 further comprises a rear wiper motor 18 arranged to oscillate a rear wiper assembly 20 across a rear windscreen 22 in order to clear the rear windscreen 22 of, for example, rainfall.

A front wiper switch assembly 24 comprises a manually oper:ited.,vii (11 to select between four positions for the front wiper motor 12; ""Off' 0, intermittent wipe 1, slow wipe 2, and fast wipe 3. The rear wiper motor 18 is controlled by a rear wiper switch 30 which is manually switchable between two positions "Off'A and "On" B. A wiper controller 26 is arranged to control the motors 12, 18 in response to their respective switches 24, 30. The controller 26 is programmed to operate the front wiper motor 12 to oscillate the front wipers 14 across the front windscreen 16 at a predetermined rate appropriate 1() the position selected on the switch 24.

The controller 26 is arranged to operate the rear wiper motor 18 to oscillate the rear wiper assembly 20 across the rear windscreen 22 only when the rear wiper switch 30 is placed in the "On" position B. The controller 26 causes the rear wiper assembly 20 to wipe the rear windscreen 22 in a predetermined manner which consists of a pre-set number of sweeps of even mark ratio across the rear windscreen 22 upon selection B, followed by an intermittent wipe phase consisting of sweeps across the rear windscreen 22 of uneven mark space ratio in which the delay between sweeps is longer than the duration of the sweeps themselves, in similar fashion to the intermittent wipe 1 of the front wiper 14.

The controller 26 can be programmed during manufacture and later selectively re-programmed by a programming means (not shown) to Preset the manner in which the rear wiper 20 wipes the rear windscreen 22. This allows the manufacturer or user to programme the frequency at which the controller 26 operates the rear wiper 20 to wipe the rear windscreen 22 so that, for example, the rear wiper speed changes automatically when the front wiper speed is changed using the switch 24.

For example, the rear wiper 20 is arranged to wipe the rear windscreen 22 as described above when the front wiper switch 24 Is in its lilt (1111111M, lit wipe 1 or slow speed 2 positions so long as the rear wiper switch 30 Is in t he "On" position B. If the front wiper switch 24 is then switched to its fast wipe position 3, such as during exceptionally heavy rainfall or a typhoon, the controller 26 automatically alters the manner in which the rear wiper motor 18 operates the rear wiper assembly 20. Under these circumstances, the speed of the rear wiper 20 remains at a constant rate of equal mark space ratio rather than change to an intermittent phase after the predetermined number of wipes. The frequency of this altered wipe rate of the rear wiper assemblY may be also be varied in accordance with instructions held in the controller 26, for example to increase its frequency of oscillation.

This invention is particularly useful in sales territories which are prone to sudden and exceptionally heavy rainfalls, such as typhoons. Under those conditions, an intermittent rear wiper may be inadequate to sufficiently clear the rear windscreen 22. When a sudden downpour comes, all the user needs to do is switch the front wiper switch 24 to its fast wipe mode 3 and the rear wiper 20 will automatically wipe the rear windscreeil 22 aL a constant rate, which can be increased or decreased with ease using a programming means. The invention therefore improves visibility and thus safety.

The implementation of the constant and / or increased WI'PC.' 1',I[(' 0('('LIIS automatically and does not therefore require the user to alter any settings.

This further improves safety because the user is not distracted from driving by having to look for extra controls.

The invention can be implemented using switching technique.-. hut t Iii, may prove to be less than cost-effective if the volume of vehicles sold in a territory where the feature is desired is low compared with the manufacturer's major volume markets. The invention is therefore particularly useful when a wiper controller 26 is fitted, as the invention can be implemented by software changes rather than by fitting a dedicated switch assembly to incorporate the additional function.

Claims

7CLAIMS

1. A vehicle including a first wiper means arranged III USe tO selectively wipe a first window in one of at least two modes and i second wiper means arranged in use to selectively wipe;I '4econd window in a predetermined manner, wherein the second wiper means is arranged to automatically alter the manner in which it wipes the second window in response to an alteration in the mode selected by the first wiper means for wiping the first window.

2. A vehicle according to Claim 1, the first mode comprising a first wipe rate and the second mode comprising a second wipe rate of increased frequency and wherein the alteration to the manner in which the second wiper means wipes the second window comprises an automatic increase in the frequency of its own wipe rate when the first wiper means is arranged to operate in the second mode.

3. A vehicle according to Claim 1 or Claim 2, each of the wiper means comprising a respective wiper selection switch, wherein the alteration to the manner in which the second wiper means, when selected, wipes the second window is made automatically when the first wiperselection switch is moved into a position in which it selects the second inode (& the first wiper means.

4. A vehicle according to any preceding claim, wherein the second wiping means is arranged in its unaltered condition to wipe the second window at a rate which includes an intermittent wipe phase.

5. A vehicle according to Claim 4, wherein the alteration to the manner in which the second wiper means wipes the second window comprises a change from the intermittent wipe phase to a constant wipe phase.

6. A vehicle according to Claim 5, wherein the wiping rate of the second wiper means during said constant wipe phase is of a higher frequency than its wipe rate during its intermittent wipe phase.

7. A vehicle according to any preceding claim, wherein the first window comprises a front windscreen of the vehicle.

8. A vehicle according to any preceding claim, wherein second window comprises a rear windscreen of the vehicle.

9. A vehicle substantially as described herein -with reference to the accompanying drawing.

10. A wiper system for a vehicle according to any preceding claim.

11. A controller for a wiper system according to Claim 10, wherein the controller is programmable to control said first and second wipelmeans.