GB2072879A

GB2072879A - Windscreen wiper control

Info

Publication number: GB2072879A
Application number: GB8009754A
Authority: GB
Original assignee: LANDMASS Ltd
Current assignee: LANDMASS Ltd
Priority date: 1980-03-22
Filing date: 1980-03-22
Publication date: 1981-10-07
Also published as: GB2072879B

Abstract

A switch, which may be a single push button, can be operated to select fast continuous operation of windscreen wipers (by two rapid pushes), slow continuous operation (by two slower pushes), intermittent operation at a desired interval (by pushing once and then again after the desired interval), or single cycle operation (by pushing once only). Pushing the button while the wipers are operating may be used to re-select the mode of operation or (by pushing once) to park the wipers.

Description

SPECIFICATION Windscreen wiper control means This invention relates to windscreen wiper control means for automobiles, railway engines, ships, aeroplanes or other vehicles.

Conventionally, modern windscreen wipers can be operated at fast or slow speeds, or intermittently, selection of the speed or mode of operation being effected by means of a four position switch (the fourth position, of course, being "off"). This is a substantial step forward from the early windscreen wipers, which had only single speed operation. Further improvement is to be found in an arrangement only very recently available, in which the period between wiping cycles in the intermittent operation mode may be varied by means of a rheostat.

The present invention provides still further improvement in regard to the ease of operation of the wipers.

The invention comprises windscreen wiper control means comprising switch means operable to initiate intermittent actuation of the wipers and thereafter operable at a selected time after such initiation to determine the time period of intermittent actuation.

Said switch means may comprise a single, momentary action switch -for example, a simple push button - operable to initiate intermittent actuation and to determine said time period.

Said switch means may also be operable to select continuous operation of said wipers, and may be operable to select different speeds of continuous operation.

The control means may comprise a single unidirectional switch - such as, again, a push button - to control all modes of operation and to stop and park the wipers.

The control means may comprise timing means adapted to emit wiper-actuating pulses at regular intervals equal to the interval between first and second operations of said switch means. Said timing means may be operable only by successive operations of said switch means separated by a time interval greater than the time taken for a single wiping cycle. Said timing means may also be operable only by successive operations of said switch means separated by a time interval less than a predetermined time interval - say predetermined time interval may be about 15 secs.

The control means may comprise continuous operation selection means adapted to select continuous operation of the wipers on successive operations of said switch means separated by a time interval less than the time taken for a single wiping cycle. A control means for two speed continuous operation of the wiper means may have said continuous operation selection means adapted to select fast continuous operation of the wipers on rapid successive operations of said switch means and slow speed continuous operation on slower successive operations of said switch means.

The control means may be adapted to operate single or intermittent wiping cycles at slow speed.

Said switch means may be operable by successive operations separated by a time interval greater than a given time interval, to cause singlecycle, non-repeating operations of said wiping means.

The control system may comprise a microprocessor.

One embodiment of windscreen wiper control means according to the invention will now be described with reference to the accompanying drawing, in which the single figure is a block diagram.

The figure illustrates windscreen wiper control means 1 1 comprising switch means 12 operable to initiate intermittent actuation of the wipers and thereafter operable at a selected time after such initiation to determine the time period of intermittent actuation. Said switch means 12 comprise a single, momentary action switch, namely a unidirectional, push-button switch, operable to initiate intermittent actuation and to determine said time period.

The control means 1 1 are also operable - by, again, the switch 12, to select continuous operation of the wipers, and, in fact, to select different speeds - fast and slow - of a two speed wiper arrangement. The same push-button switch 12 is also used to stop and park the wipers.

The control means 1 1 include timing means 13 adapted to emit wiper-actuating pulses at regular intervals equal to the interval between first and second operations of the switch 1 2. The timing means 13 may be of any desired kind, but an electronic digital counter arranged to emit a timing pulse at an interval preselected by spaced apart input pulses may be preferred and could be integrated in a microprocessor control arrangement covering the whole operation.

The timing means 13 are arranged to be operable only by successive operations of the switch 12 separated by a time interval greater than the time taken for a single wiping cycle - in an electronic arrangement, this is easily achieved by programming the microprocessor. It is also arranged - also by programming in an electronic arrangement - that the timing means 13 are operable only by successive operations of the switch 12 separated by a time interval less than a predetermined time interval - which will of course be greater than the time for a single wiping cycle and desirably about 15 seconds.Thus repeated operation of the switch 12 at an interval between say about two and about fifteen seconds will cause intermittent operation of the wipers with a frequency determined by the said interval.

Continuous operation of the wipers is effected by selection means 14 therefor actuated on successive operations of the switch 12 separated by a time interval less than the time taken for a single wiping cycle. Two speed continuous operation is effected by said selection means 14 comprising a short time recognition circuit 1 4a and a longer time recognition circuit 1 4b - the circuit 1 4a, for example locks on the fast wipe switch 15 of a conventional two speed wiper arrangement on receipt of two pulses separated by a time interval less than that taken for the first stroke of wiper operation. Circuit 1 4b locks on the slow wipe switch 16 of the wiper arrangement on receipt of two pulses separated by a time interval longer than that for a single stroke, but less than that for a complete cycle.

Single operations of the switch 12 separated by a time interval greater than the preselected time interval of about 1 5 seconds referred to above will not effect repeated operation of the wipers, but will just initiate a single wiping cycle, terminated by the usual parking switch 17.

The circuit 1 4b and the timer 13 are connected to the slow wipe switch 16 through an OR gate.

Thus intermittent actuation (or single actuation) of the wipers is effected at the slow rate.

The circuits 12, 1 4a and 1 4b are included in a microprocessor with a clock 18 and a pulse recognition circuit 19 that generates pulses acceptable to the other circuits and controls a relay 20 interposed between the electronic circuits and the wiper arrangement. A diode 21 prevents feedback to the circuit 19 that might lead to spurious operation of the wipers.

To cancel operation in whatever mode is selected -fast continuous wipe, slow continuous wipe or intermittent wipe at selected frequency, a single operation of the switch 12 resets whichever of the circuits 12, 1 4a or 1 4b is operative and the wipers come under the control of the parking switch 17 which returns the wipers to the parked position, unless another operation of the switch 12 is effected within one or other of the periods for selecting fast wipe, slow wipe or intermittent wipe.

Of course, although a single push-button control has been described, it could be arranged that separate buttons - or a multiposition switch could be provided for selecting "fast wipe", "slow wipe" and "park" modes.

The arrangement described with reference to the drawing can be used with conventional windscreen wiper motor arrangements and moreover can be used in conjunction with washand-wipe arrangements. Such could be, as now, under the control of a separate switch, which might also operate headlamp wash-and-wipe equipment, which initiates a half dozen or so wiping cycles before returning the wipers to the parked position.

Claims

1. Windscreen wiper control means comprising switch means operable to initiate intermittent actuation of the wipers and thereafter operable at a selected time after such initiation to determine the time period of intermittent actuation.

2. Control means according to claim 1, said switch means comprising a single, momentary action switch operable to initiate intermittent actuation and to determine said time period.

3. Control means according to claim 1 or claim 2, said switch means being operable to select continuous operation of said wipers.

4. Control means according to claim 3, said' switch means being operable to select different speeds of continuous operation.

5. Control means according to any one of claims 1 to 4, comprising a single unidirectional switch to control all modes of operation and to stop and park the wipers.

6. Control means according to any one of claims 1 to 5, comprising timing means adapted to emit wiper-actuating pulses at regular intervals equal to the interval between first and second operations of said switch means.

7. Control means according to claim 6, said timing means being operable only by successive operations of said switch means separated by a time interval greater than the time taken for a single wiping cycle.

8. Control means according to claim 6 or claim 7, said timing means being operable only by successive operations of said switch means separated by a time interval less than a predetermined time interval.

9. Control means according to claim 8, said predetermined time interval being about 15 seconds.

10. Control means according to claim 6 or claim 7, or claim 8, comprising continuous operation selection means adapted to select continuous operation of the wipers on successive operations of said switch means separated by a time interval less than the time taken for a single wiping cycle.

1 1. Control means according to claim 10, for two speed continuous operation of the wiper means, said continuous operation selection means being adapted to select fast continuous operation of the wipers on rapid successive operations of said switch means and slow speed continuous operation on slower successive operations of said switch means.

12. Control means according to claim 1 1, adapted to operate single or intermittent wiping cycles at slow speed.

13. Control means according to any one of claims 1 to 12, said switch means being operable, by successive operations separated by a time interval greater than a given time interval, to cause single cycle, non-repeating operations of said wiping means.

14. Control means according to any one of claims 1 to 13, comprising a microprocessor.

15. Control means substantially as hereinbefore described with reference to the accompanying drawing.