GB2052799A

GB2052799A - Cleaning apparatus for windows of motor vehicles

Info

Publication number: GB2052799A
Application number: GB8017503A
Authority: GB
Original assignee: SWF Spezialfabrik fuer Autozubehoer Gustav Rau GmbH
Current assignee: SWF Auto Electric GmbH
Priority date: 1979-06-02
Filing date: 1980-05-29
Publication date: 1981-01-28
Also published as: JPS565247A; DE2922685C2; IT1130645B; GB2052799B; IT8022245A0; JPH0464895B2; DE2922685A1; FR2458104A1

Abstract

In a cleaning (wiper) installation for motor vehicles, including a wiper motor (10) and an operating switch (22), a programme controller (30) is provided to control the mode of operation of the wiper motor in dependence on a switching signal released from the operating switch (22) and conducted to the controller (30) via a single lead. The switching signal is a switching pulse or a switching pulse sequence, and characteristic features of the pulse or pulse sequence, such as occurrence pulse time, interval time, pulse height, determine which mode of operation the controller actuates, for example, intermittent wipe, slow continuous, fast continuous, switch-off. Various arrangements are described with reference to other figures, for example, wash/wipe modes of operation and interconnection of windscreen and rear window wiper installations. <IMAGE>

Description

SPECIFICATION Cleaning apparatus for windows of motor vehicles This invention relates to cleaning apparatus for panes on motor vehicles.

In order to meet the requirements of road traffic modern motor vehicles are equipped with cleaning installations for the windscreen which, in dependence on the position of an operating switch can carry out series of different wiper-washer operations. These days during continuous operation in most motor vehicles the wiper speed can be changed over from a slow speed to at least one quick speed.

In addition many wiper installations provide intermittent operation. Besides a so-called tapwipe operation is possible. This tap-wipe operation is a mode of operation in which only one wiper operation is released. Finally it is also known to release a wiper-washer programme in a particular position of the operating switch, in which for example the washing pump motor is started at first, then the wiper installation is switched on with delay and after termination of the washing operation some additional wiping cycles are carried out. Besides it is ensured in all modern wiper installations that after switching off of the operating switch the wipers are entering into a defined parking position. This mode of operation can be called switching-off operation.

In presently series-produced wiper installations various control leads are necessary for the control of the wiper motor and, if required, for the washing pump motor. Mostly the operating currents for the motor also flow through these control leads, so that the switch and these control leads must be designed appropriately and thus are very expensive.

In order to reduce the wiring a circuit arrangement for a windscreen wiper installation on motor vehicles is already known, in which merely one control lead is provided between one switch and one programme controller. Through this control lead differing potentials are conducted to the programme controller for the various modes of operation.

Such a circuit arrangement works only satisfactorily in a motor vehicle if the voltages assigned to the individual modes of operation differ sufficiently, for it has to be taken into consideration that the supply voltage in a motor vehicle varies considerably. Because usually in a motor vehicle only a low voltage is available the number of the modes of operation adjustable in this manner is limited.

The invention is based on the problem of creating a cleaning apparatus or installation in which via a single control lead a plurality of differing modes of operation may be selected.

Thereby the circuit arrangement is to be designed in a simple manner and the cleaning installation is to be operated easily.

According to the present invention there is provided cleaning apparatus, for use with windows of motor vehicles, comprising a wiper motor with or without a washing pump motor which via a programme controller is/are controllable in various modes of operation, whereby the mode of operation is adjustable via an operating switch, the switching signal of which switch is conducted to the programme controller via a control lead, and wherein the switching signal is a switching pulse or a switching pulse sequence and the mode of operation depends on at least one characteristic feature of the switching pulse or switching pulse sequence and/or upon the adjusted mode of operation when the switching pulse or switching pulse sequence is released and/or upon the time of release of the switching pulse or of the switching pulse sequence.

The invention is thereby based on the idea that switching pulses or switching pulse sequences have a plurality of characteristic features, which can be evaluated by the programme controller. By a combination of these characteristic features a plurality of modes of operation can be actuated. Besides a number of characteristic features of the switching pulses or of the switching pulse sequences are nearly independent of the operating voltage in the motor vehicle, so that the evaluation is reliable and can very easily be effected.

The basic idea of the invention can be realised in such a manner that to particular characteristic features of the switching pulses or the switching pulse sequences particular modes of operation are directly assigned.

Such a solution entails the advantage that independently of the mode of operation adjusted at the time being a defined mode of operation is released with the next switching pulse.

But the invention can also be realised in such a way that upon release of a switching pulse a mode of operation is turned on which merely depends on the preceding mode of operation. Besides the mode of operation to be turned on can be made dependent on the time of release of the switching pulse. In both cases the system can be designed in such a way that only the release of a switching pulse is evaluated, and that the type of switching pulse or switching pulse sequence is of no importance. Such types are especially simply and reliably to be produced.

The mode of operation can be made dependent on time-related characteristic features of the switching pulses or of the switching pulse sequences, for instance on the duration of a switching pulse or on the time interval between two switching pulses or also on the number of switching pulses per time unit. It is also conceivable to make the mode of operation dependent on the mark-to-space ratio of a switching pulse sequence. By a combination of all these characteristic features and appropriate evaluation and differentiation in the programme controller a plurality of differing modes of operation may be realised. Additionally one can of course make the mode of operation dependent on the voltage level or current level of the switching pulse, whereby the possibilities of variation are increased further.

A version is preferred in which the mode of operation changes upon every new switching pulse independently of its characteristic feature in cyclic succession. For this purpose the programme controller can comprise a kind of ring counter which with each switching pulse is advanced by a step.

In order to avoid that in such a version all modes of operation programmed between the mode of operation at the time being and the desired mode of operation have to be switched on by short-time switching pulses, when the installation is to be switched off or a particular mode of operation is to be switched on, according to a further advantageous development of the invention one can provide that it is advanced in cyclic succession with every switching pulse having a particular and characteristic feature, but with every switching pulse having a different characteristic feature a particular mode of operation is selected. It is also conceivable for instance to switch the ring counter forwards by a short-time pulse, however backwards by a long-time pulse, so that starting from a particular mode of operation another mode of operation can be quickly switched on.A series of further possibilities of combination have been found which enable an especially simple operation of the cleaning installation.

These variants are described in detail hereinafter in connection with the drawings. Additionally one can consider the fact whether a switching pulse is for instance released during a wiper operation or only after termination of a wiper operation. This differentiation is especially appropriate in connection with intermittent operation, because then the interval time can be varied in dependence on the period of time between the two switching pulses. Because of the many possibilities of variation in an embodiment according to the invention in addition to the basic modes of operation turned on also particular features of the individual modes of operation, for instance the interval time, can be affected, whereby a corresponding switching signal is conducted to the programme controller via the only control lead.

Of course it is conceivable that besides the control lead through which the mode of operation is affected, further control leads are provided, through which for instance the interval time or specific wiper-washer programmes are released too. In this connection it is also conceivable to adjust other elements of the cleaning installation via a separate control lead, for instance to increase the contact pressure of the wiper blades on the windscreen, when the vehicle is driving with high speed.

Embodiments of the invention will now be described with reference to the accompanying drawings, in which Figs. 1 to 5 and 7 to 8 show circuit diagrams of various types; Fig. 6 shows a voltage-time diagram in order to explain the function counter used in the embodiment of Fig. 5.

In Fig. 1 a wiper motor which can be operated with two differing wiper speeds is designated by 10. For slow continuous operation the wiper motor 10 is controlled via brush 11, for rapid continuous operation via brush 12. To the wiper motor a limit switch 13 is assigned in known manner which in the parking position occupies the position shown.

Outside of the parking position this limit switch makes a connection to one terminal 14 of a voltage source (not shown in detail) whose positive pole is designated by 15. The wiper motor is started, if one of relays 16, 17, 18 or 19 is excited. Thereby the mode of operation in which the cleaning installation is operated depends on which one of these relays is excited.

When the relay 19 is excited, rapid continuous operation is commenced, and slow continuous operation is commenced when the relay 18 is excited. The relay 17 is controlled via a pulse generator 20 which is triggered by the limit switch 13. This relay 17 is periodically controlled, so that intermittent operation is effected. The relay 16 is controlled in the socalled switching-off operation, that is when the wipers are to be moved into the so-called parking position.

An essential component of a programme controller as a whole designated by 30 is a kind of ring counter 31 with a clock input 32.

An operating switch 22 is connected to this clock input 32 via sole control lead 21. The mode of operation of this ring counter has to be imagined in such a way that only one of outputs 36, 37, 38 or 39 is activated at a time and with every positive slope on the clock input 32 the just activated output is switched off and the subsequent output is activated instead in cyclic succession. When the output 39 is activated, the output 36 is activated with the following switching pulse on the clock input 32, whilst the output 39 is switched off.

In the following description of the embodiment of Fig. 1 it is started from the fact that the output 36 is activated and the limit switch 13 occupies the position shown. Thus the relay 16 is de-energised. Because the other outputs 37, 38 and 39 are not activated, there is also no current flow through the windings of the other relays 17, 18 and 19.

Thus the cleaning installation is idle, because the current supply to the electric motor 10 is interrupted.

If the operating switch 22, which is developed as touch switch, is actuated now, the ring counter 31 advances with the positive slope of the switching pulse available on the control lead 21. This means that the output 36 activated until now is switched off, but the output 37 is activated. Thus the pulse generator 20 is switched on and the relay 17 excited. Thus operating current flows from the terminal 15 to the brush 11 of the wiper motor and the motor begins to rotate. Shortly after that the limit switch 13 closes a connection to earth 14 which, however, does not affect the pulse generator 20 whose trigger input 23 is connected to the limit switch.

Only when the limit switch 13 opens again after one wiper operation is completed is the pulse generator 20 switched off and thus the relay 17 is de-energised. Thus the motor circuit is interrupted. After a certain delay time the pulse generator 20 switches on the relay 17 automatically and the operation is repeated. That means if the output 37 of the programme controller 30 is activated, the wiper installation is controlled in intermittent operation. If now during intermittent operation the operating switch 22 is actuated anew, the output 37 is switched off and the output 38 is activated. Thus the relay 18 operates. Now the wiper motor is driven with slow wiper speed in continuous operation. The output 39 is activated with the next switching pulse, thus the relay 19 becomes excited and the wiper motor is driven in rapid continuous operation.The output 36 is activated with the next switching pulse on the control lead 21.

If, at this time, the wipers are positioned outside of the parking position the limit switch 13 is closed. Then the relay 16 becomes excited and closes the motor circuit until the wipers enter their parking position. Then the relay 16 is deenergised, though the output 36 remains activated, because the limit switch 13 opens again. This mode of operation is named switching-off operation. Thus in this simple version according to Fig. 1 the mode of operation is turned on by a switching pulse on the only control lead 21, whereby the new mode of operation depends on the mode of operation at the time of release of the switching pulse. The mode of operation changes with each new switching pulse in a cyclic succession independently of a characteristic feature of the switching pulse.The cyclic succession is thereby in accordance with the requirements suitably determined in such a way that from switching-off operation it is at first changed over into slow continuous operation and later into rapid continuous operation.

Of course also other successions are conceivable, but the embodiment shown in Fig. 1 is preferred, because starting from the switching-off position the modes of operation are passed in such a way as the practice requires, when it is beginning to rain.

Fig. 2 shows a slightly modified and improved embodiment, wherein for the sake of simplicity in the main only the control of the programme controller 30 is shown. The ring counter has now a reset input 33, which is controlled via a monostable flip flop 40 responding with delay. A pulse available on this reset input 33 ensures that the output 36 will be activated, but all other outputs are switching off. The flip flop 40 for instance is laid out in such a way that a reset pulse may be measured on its output, when the operating switch is actuated longer than 500 msec. For functioning of the version according Fig. 2 this means that the ring counter is advanced with every pulse on the control lead 21, but with a long-time switching pulse the switching-off operation is turned on in any case.The new mode of operation thus in this version depends on the one hand on the preceding mode of operation, but on the other hand with a long-time switching pulse a defined mode of operation is turned on which is independent of the preceding mode of operation. Thus the mode of operation depends on a time-related characteristic feature of the switching pulse, namely the duration of the switching pulse. Thereby two alternatives are conceivable. One can release advancing of the ring counter 31 by the switching-on slope of the switching pulse which, however would entail that, though one wants to stop the wiper installation, for the time being the following mode of operation is turned on. Therefore a solution in which the new mode of operation is only turned on with the switching-off slope of the switching pulse as is shown in Fig. 2 is preferable.Thus such a solution comprises also the feature that the mode of operation only changes in cyclic succession with every new switching pulse having a particular and characteristic feature, namely with a short-time switching pulse only.

In the version according to Fig. 3 a flip flop 41 is series connected to the clock input 32 of the ring counter 31. The inverting output 42 of this unit simultaneously is the output 36 of the programme controller through which the relay 16 is controlled. The gates 44 behind the outputs 37, 38, 39 are controlled through the other output 43. In this version a trigger signal is conducted on the control lead 21 to the ring counter 31 only with every second switching pulse, and indeed at any time, when the output 43 becomes activated.

Thus the gates 44 are simultaneously opened.

This means that the modes of operation are change over only with every second switching pulse in cyclic succession. The flip flop 41 is reset with every switching pulse in between and thus the output 36 is activated whilst the gates 44 are blocked.

Thus in this version it is continuously changed over from one mode of operation to switching-off operation and then to another mode of operation and again to switching-off operation etc.

In the version according to Fig. 4 an ORgate 45 is series-connected to the clock input 32 of the ring counter 31, which OR-gate is controlled via the operating switch 22 or via a clock generator 46. A timing element 47 with operate delay is series-connected to the clock generator 46. The clock generator 46 is controlled through this timing element 47, when the operating switch is actuated longer than a given time interval, for instance longer than 500 msec. Then the clock generator 46 takes care that the modes of operation are advanced in cyclic succession within short time intervals. Thus it becomes possible, for instance starting from intermittent operation, to change over to switching-off operation through a longtime switching pulse. In order to recognise which mode of operation is switched on at the time being indicating lamps 49 are provided at the outputs of the ring counter 31.Thus again a characteristic feature of the switching pulse is evaluated, namely the pulse duration.

A further variant will now be described with reference to Figs. 5 and 6 which is preferably realised by using a microcomputer. This circuit diagram according to Fig. 5 only shows basic units for a better understanding of the functioning of the installation. The wiper motor 10 is controlled via a switching relay 50 which is connected to the output of an ORgate 51. One input of this OR-gate 51 is controlled by a unit 52 which can release a so-called tap-wire operation or a wiper-washer programme. Functioning must be imagined in such a way that upon release of a short-time switching pulse the input 53 of said unit 52 is controlled via the operating switch 22 and thus the switching relay 50 is excited via the OR-gate 51 until the limit switch 13 again occupies the position shown after termination of a wiper operation.Then the input 54 of said unit 52 is activated and the switching relay 50 is switched off again. Thus the socalled tap-wipe operation is released with a short-time switching pulse, that means a wiper operation is carried out.

A function counter 60 with a clock input 61, a reset input 62, a blocking input 63 and two outputs 64 and 65 is provided in this embodiment according to Fig. 5. As the voltage-time diagram according to Fig. 6 shows the outputs 64 and 65 can only be activated alternately or be switched off both.

A switching position in which both outputs are activated is not provided. A signal on the reset input 62 ensures that both outputs 64 and 65 are switched off. A signal on the blocking input 63 prevents that clock pulses are processed by this function counter 60.

The blocking input 63 is connected to the output of a timing element 67 with operate delay. Thus at this blocking input 63 a blocking signal is available when a long-time switching pulse is released via the operating switch 22. In the version according to Fig. 5 an interval time generator is designated by 68 whose output is connected to a further input of the OR-gate 51. A number in counter 69 determines the interval time of the interval time generator 68. To the reset input 62 of the function counter 60 a delay network 70 is series-connected which is triggered via an AND-gate 71. The input of said AND-gate 71 is connected to the output 64 of the function counter 60, the other inverting input of said AND-gate 71 to the limit switch 13. This means that said delay network 70 is only triggered when the wiper motor occupies its end position and when a signal is available on the output 64.The delay network 70 now provides that a certain time after the wiper operation is terminated, for instance 20 sec later, a reset signal is released. From Fig. 6 it can be seen that then both outputs 64 and 65 are switched off.

The output 65 of the function counter 60 is connected to the inputs of two AND-gates 73 and 74. The one AND-gate 73 affects the interval timer 68, the output of the other AND-gate 74 is connected to a further input of the OR-gate 51. When the AND-gate 74 is activated, the wiper installation is controlled in continuous operation, when however, the ORgate 73 is activated, the wiper installation works in intermittent operation. Either is only possible when the output 65 is activated. The differentiation of which mode of operation is to be activated is provided by a time recognition element 75 which follows to the counter 69. If the count of the counter is higher than a predetermined value the AND-gate 73 is activated and thus intermittent operation is switched on, if the count of the counter is smaller than a predetermined value, continuous operation is switched on.

In detail the embodiment according to Fig.

5 functions as follows: As already described the first short-time actuation of the operating switch 22 releases the tap-wipe operation via the unit 52. At the same time the function counter is advanced, so that the output 64 becomes activated.

When the wiper operation is terminated and a new switching pulse is not released within a given time interval, for instance within 20 sec, the delay network 70 conducts a reset signal to the reset input 72. Thus both outputs 64 and 65 are switched off again.

The following description starts from the fact that the tap-wire operation is turned on by a single short switching pulse. If a second switching pulse is released now, the output 64 is switched off according to Fig. 6, but the output 65 is activated. Thus now either intermittent operation or continuous operation is possible. The differentiation depends on which time interval has passed between the first and the second switching pulse. If the second switching pulse is released during the wiper operation or for example within a given time interval after termination of the wiper operation the count of the counter 69 is relatively low and the AND-gate 74 is activated via the time recognition element 75.

Thus continuous operation is turned on. If, however, the second switching signal is released much later after termination of the wiper operation, but within of 20 sec after its termination, the count of the counter is relatively high and the AND-gate 73 is activated.

Thus intermittent operation is activated.

Thereby the interval time corresponds to the period between the first and the second switching pulse.

Independently of whether intermittent operation or continuous operation is turned on now upon release of the next switching pulse the output 64 is activated again and the output 65 switched off. In this switching condition of the function counter 60 the wiper operation is terminated.

If now a switching pulse is released anew either continuous operation is turned on or intermittent operation with a possibly changed interval time. If no new switching pulse is released both outputs 64 and 65 are again switched off after expiration of the delay time of the delay network 70.

Thus the function counter 60 operates like a kind of ring counter, whereby the output 64 is activated with every odd-numbered switching pulse and the output 65 with every evennumbered switching pulse. Both outputs are switched off, when no further switching pulse is released within a delay time, when the output 64 is activated. Of course it is assumed that none of the outputs of said function counter 60 is activated, when the supply voltage is switched on for the first time.

If a long-time switching pulse is released with the operating switch 22, the timing element 67 is activated. On the one hand the timing element blocks the function counter and on the other hand it switches on the unit 52 via the input 55. Thereby relay 56 for washing pump motor 57 is controlled and that as long as the operating switch 22 is actuated. After switching-off of the operating switch several additional wiping cycles are carried out. By the feedback of the signal of the timing element 67 to the blocking input 63 it is achieved that the count of the function counter 60 is not affected by a long-time switching pulse. This means that afterwards the mode of operation continues which has been turned on before the long-time switching pulse was released.

In the embodiment according to Fig. 5 thus the new mode of operation among other things depends on the time of release of the switching pulse. Thereby this time also depends on the course of the wiper operation.

Finally the mode of operation also depends on the number of switching pulses per time unit.

If, starting from the rest position, the operating switch 22 is shortly actuated twice in succession continuous operation is switched on. If however, the time interval between the two switching pulses is bigger, intermittent operation is turned on.

Fig. 7 shows a version in which two ring counters 80 and 81 are provided, whereby one ring counter determines the mode of operation and the other ring counter the interval between pulses. Besides in this embodiment the mode of operation is made dependent on the voltage level of the switching signal. For this purpose a voltage indicator 82 is provided, whose one output 85 affects the ring counter 80 and whose other output 86 affects the ring counter 81. The input of this voltage indicator 82 is connected to the operating switch 22 via the only control lead 21.

The operating switch has two pushbuttons 83 and 84 which are connected to a resistance network in such a way that upon release of the pushbutton 83 the full operating voltage and upon release of the pushbutton 84 for instance only half of the operating voltage is conducted to the voltage indicator 82 as a switching pulse. The output 85 of the voltage indicator 82 is only activated, if the key 83 is actuated, whilst the output 86 is activated when the key 84 is actuated. A gate 87 is connected to the output 86. Said gate is controlled by the output 37 of the ring counter 80. In detail this version functions in such a way that upon actuation of the pushbutton 83 the modes of operation are continuously changing in cyclic succession, as it has been described in detail with respect to Fig. 1.If the output 37 of said ring counter 80 is activated and thus the intermittent operation is switched on, the ring counter 81 can be advanced by actuating the pushbutton 84, because the gate 87 is then opened. Thus various outputs of said ring counter 81 are activated in cyclic succession, whereby these outputs affect the pulse generator 20 in such a way that the interval time is changed. Thus in this embodiment it is assumed that a certain interval time is predetermined when intermittent operation is switched on. If now the key 84 is actuated, this interval time can be prolonged or shortened step by step. Of course such a system is conceivable too in the case that not the voltage or current levels of the switching signals, but for instance the duration of the switching signal is evaluated.

Finally also in this installation for instance a separate washing programme can be released independently of the ring counter 80 by further differing voltage levels.

It is emphasised that of course the drawings only serve to explain the possible switching function. The programme controller is preferably made by integrated techniques, if possible by using series produced microprocessors or microcomputers.

The invention is with particular advantage used for rear window wiper installations because then the fact that only one control lead is necessary is of special importance. Of course also the windscreen wiper installation can be controlled in the same manner. In Fig.

8 an embodiment is indicated in which in dependence on characteristic features of the switching pulse the rear window wiper installation is coupled to the windscreen wiper installation. Thereby it is started from the following considerations: If the windscreen wiper installation is operated, most certainly also the rear window wiper installation has to be switched on, though the rear window wiper installation may carry out less wiper operations per time unit than the windscreen wiper installation. If the windscreen wiper installation is switched off, the rear window wiper installation is at the most needed for one cleaning cycle.

In order to meet these requirements it is provided in the embodiment according to Fig.

8 that the rear window wiper installation carries out one wiper operation upon release of a short-time switching pulse, but that upon release of a second short-time switching pulse within a given time interval the rear window wiper installation is coupled with the windscreen wiper installation in such a way that the rear window wiper installation only carries out a wiper operation with every fourth wiping cycle of the windscreen wiper installation and that upon release of a third short-time switching pulse the rear window wiper installation is switched off after termination of the wiping cycle.The result is that upon each short-time actuation of the operating switch the wiper installation is switched on for one wiping cycle, each even-numbered switching pulse couples the rear window wiper installation to the windscreen wiper installation and each following odd-numbered switching pulse switches the rear window wiper installation again on so-called wiping operation, in which the motor is switched off after the wiper operation is terminated.

In Fig. 8 the rear window wiper motor is designated by 100. To said motor a position switch 101 is assigned and the motor is switched via relay 102. This relay is controlled via an OR-gate 103 and a following inverter. The OR-gate 103 has an input which is directly connected to the operating switch 22. In this manner it is ensured that upon actuation of said switch 22 a wiper operation is carried out immediately.

But upon actuation of the switch 22 a timing element 104 is set too, which only triggers a store 106 via a following inverter and via the gate 105, if the actuating time is for instance longer than 0.5 sec. With setting the store 106 one input of the OR-gate 103 is controlled simultaneously, so that the relay 102 remains energised until the store 106 is reset. When the store 106 is set a counter 108 is released via the gate 107, when the switch 22 is released. Said counter counts the pulses of the position switch 101. A comparator 109 follows the counter 108 and compares the count of the counter 108 to a number which may be predetermined in the block 110 at random, for instance to the number 3. If the numbers are equal a reset signal for the store 106 is released via monostable flip flop 111.Thus in this manner it is ensured that the wiper motor 100 of the rear window wiper installation carries out three wiper operations upon a long-time switching pulse of the operating switch 22. This is part of a wiper-washer programme in which, upon actuation of the operating switch 22, a washing pump is additionally switched on with delay, and switched off again, when the switch 22 is released, whereby three additional wiper operations are still carried out. In connection with this first part of the circuit arrangement it is additionally pointed out that the counter 108 is reset at any time the store 106 is set via a monostable flip flop 112.

Upon actuation of the switch 22 a store 113 is set simultaneously. Thus a counting stage 114 is reset via timing element 115 and at the same time the counting input is released. The counting stage 114 counts the clock pulses of a generator 116. A comparator 117 follows, which compares the count with a number predetermined in block 118 at random, for instance the number 20, and in the case of conformity via monostable flip flop 11 9 releases a reset signal for the store 113 whose output acts on a further input of ORgate 103 via a timing element 120. Thus after actuation of the operating switch 22 the store 113 can remain set only for a quite certain period, for instance for 20 sec. If within this time interval a second switching pulse is released, a further store 121 is set via AND-gate 1 22.If it was a short-time switching pulse and the store 106 therefore has not been triggered, gate 123 is opened, so that a divider stage 124 is activated.

The clock input of this divider stage 124 is coupled with the limit switch 13 of the windscreen wiper motor 10 and only releases with the nth wiper operation, for instance with every fourth wiper operation, a switching signal via monostable flip flop 125, which switching signal is conducted to a further input of the OR-gate 103. If thus two short switching pulses are released by the operating switch 22 within a given time interval of for example 20 seconds, the rear window wiper installation is coupled to the windscreen wiper installation. If now a short-time switching pulse is released anew, the store 113 is reset on the one hand and the store 121 is cleared too via gates 126 and 127.Thus the divider stage 124 is de-activated and the wiper operation for the time being is terminated because one input of the OR-gate is applied to positive potential via a resistor 130 until limit switch 101 is closed in the parking position.

Of course the embodiment according to Fig.

8 only shows one possible variant. It is also conceivable to couple the rear window wiper installation to the windscreen wiper installation with the release of a short-time switching pulse and to carry out a wiper-washer programme when a second switching pulse is released within a given time interval, whereby by the release of a further, maybe long-time switching pulse out of the time interval the rear window wiper installation is again switched off or is disconnected from the windscreen wiper installation.It is conceivable too to turn on tap-wiping with a first short pulse, but with a second short pulse intermittent operation for the rear window wiper installation and with a third short pulse continuous operation of the wiper installation, whereby it can furthermore be ensured by appropriate means that the interval between the pulses regulates automatically in accordance with the frictional conditions on the rear window. Such an installation can be switched off with a long-time pulse. In another version one could, with a first short pulse, turn on intermittent operation with a self-regulating interval between the pulses, which may also be 0, and switch off the installation with a long pulse.

Thereby the washing pump could be switched on with two short pulses. Finally it would be conceivable to release a wiper-washer-operation of the rear window installation with every first pulse. This is useful on grounds of safety, but washing water may be used unnecessarily. But this shortcoming can be cured in that one fills the water container with rain water.

Claims

1. Cleaning apparatus, for use with windows of motor vehicles, comprising a wiper motor with or without a washing pump motor which via a programme controller is/are controllable in various modes of operation, whereby the mode of operation is adjustable via an operating switch, the switching signal of which switch is conducted to the programme controller via a control lead, and wherein the switching signal is a switching pulse or a switching pulse sequence and the mode of operation depends on at least one characteristic feature of the switching pulse or switching pulse sequence and/or upon the adjusted mode of operation when the switching pulse or switching pulse sequence is released and/or upon the time of release of the switching pulse or of the switching pulse sequence.

2. Apparatus as claimed in claim 1, wherein the mode of operation depends on a time-related characteristic feature of the switching pulse or of the switching pulse sequence.

3. Apparatus as claimed in claim 2, wherein the mode of operation depends on the duration of a switching pulse.

4. Apparatus as claimed in claim 2, wherein the mode of operation depends on the time interval between two switching pulses.

5. Apparatus as claimed in claim 2, wherein the mode of operation depends on the number of switching pulses per time unit.

6. Apparatus as claimed in claim 2, wherein the mode of operation depends on the mark-to-space ratio of a switching pulse sequence.

7. Apparatus as claimed in claim 1, wherein the mode of operation depends on the voltage level or current level of the switching pulse.

8. Apparatus as claimed in claim 1, wherein with each new switching pulse the mode of operation changes in cyclic succession independently of the characteristic feature of the switching pulse.

9. Apparatus as claimed in any one of claims 1 to 7, wherein with each new switching pulse with a particular and characteristic feature the mode of operation changes in cyclic succession.

10. Apparatus as claimed in claim 9, wherein with each switching pulse with a particular and characteristic feature the mode of operation is changed over in cyclic succession to the following mode of operation, and with each switching pulse with another characteristic feature the mode of operation is changed to the preceding mode of operation.

11. Apparatus as claimed in claim 9, wherein the mode of operation changes with each switching pulse with a particular and characteristic feature in cyclic succession, but with a switching pulse with another characteristic feature a predetermined mode of operation is actuated.

12. Apparatus as claimed in any one of the claims 9 to 11, wherein upon release of a switching pulse with another characteristic feature the modes of operation are automatically changed over in short time intervals.

13. Apparatus as claimed in any one of the claims 8 to 12, wherein a particular mode of operation is adjusted automatically if within a given period no switching pulse is released.

14. Apparatus as claimed in claim 1, wherein the mode of operation depends on the time of release of a switching pulse or a switching pulse sequence with respect to a wiping cycle.

15. Apparatus as claimed in claim 8, wherein upon release of each switching pulse the mode of operation is changed over in cyclic succession from switching-off operation to intermittent operation, slow and quick continuous operation and to switching-off opera tion again.

16. Apparatus as claimed in claim 11, wherein with each short-time switching signal the mode of operation is changed over in cyclic succession from switching-off operation to intermittent operation, but that with each long-time switching signal the mode of operation is changed over to switching-off operation independently of the mode of operation at the time being.

17. Apparatus as claimed in claim 16, wherein the next mode of operation is actuated by the switching-on slop of the switching pulse.

18. Apparatus as claimed in claim 16, wherein the next mode of operation is actuated by the switching-off slope of the switching pulse.

19. Apparatus as claimed in claim 11, wherein with the switching-on slope of a short-time switching pulse the mode of operation is changed over from switching-off operation to intermittent operation and slow continuous operation, and wherein with the switching-off slope of a short-time switching pulse the mode of operation is changed over from slow to quick continuous operation, and wherein upon a long-time switching pulse the mode of operation is changed over to switching-off operation.

20. Apparatus as claimed in claim 8, wherein with every second switching pulse the mode of operation is changed over in cyclic succession from intermittent operation to slow continuous operation, to quick continuous operation and again to intermittent operation, and wherein with every in-between switching pulse the mode of operation is changed over to switching-off operation.

21. Apparatus as claimed in claim 12, wherein with each short-time switching pulse the mode of operation is changed over in cyclic succession from switching-off operation to intermittent operation, to slow continuous operation, to quick continuous operation and again to switching-off operation, and wherein upon release of a long-time switching pulse the modes of operation are automatically changed over in this succession.

22. Apparatus as claimed in any one of the preceding claims, wherein upon release of a short-time switching pulse a particular mode of operation is adjusted, and wherein upon release of the next switching pulse in dependence on the time interval between the two switching pulses a second or third mode of operation is actuated.

23. Apparatus as claimed in claim 22, wherein upon release of a first short-time switching pulse the so-called tap-wipe operation is actuated, and wherein with the second switching pulse continuous operation is switched on if the second switching pulse is released during the wiper operation or within a particular time interval relative thereto, whereas intermittent operation is switched on if the second switching pulse is released later.

24. Apparatus as claimed in claim 23, wherein with each subsequent switching pulse the mode of operation is alternately changed over from continuous operation, or intermittent operation, to tap-wipe operation.

25. Apparatus as claimed in any one of claims 22 to 25, wherein switching-off operation is actuated when during tap-wipe operation no switching pulse is released in a given time interval.

26. Apparatus as claimed in any one of the preceding claims, wherein the interval time for an intermittent mode of operation may be affected by a switching pulse through the control lead.

27. Apparatus as claimed in claim 26, wherein the interval time depends on the period of time between two switching pulses.

28. Apparatus as claimed in any one of the preceding claims, wherein particular wiper-washer programmes may be released by a switching pulse through the control lead.

29. Apparatus as claimed in claim 28, wherein a long-time switching pulse releases a wiper-washer programme and wherein this long-time switching pulse does not effect a changeover of the previously adjusted mode of operation.

30. Apparatus as claimed in claim 26, wherein when the intermittent operation is turned on a particular interval time is given and the interval time is variable in steps by switching signals with particular characteristc features.

31. Apparatus as claimed in any one of the preceding claims, wherein in dependence on the mode of operation turned on by a characteristic feature of the switching pulse of the switching pulse sequence and/or at the time of release of the switching pulse or the switching pulse sequence a windscreen wiper installation is controlled and/or a rear window wiper installation.

32. Apparatus as claimed in claim 31, wherein upon release of a short-time switching pulse the rear window wiper installation carries out a wiping operation.

33. Apparatus as claimed in claim 32, wherein upon release of a second short-time switching pulse within a predetermined time interval the rear window wiper installation is coupled with the windscreen wiper installation in such a way that the rear window wiper installation only effects a wiping operation at every Hh wiping operation of the windscreen wiper installation.

34. Apparatus as claimed in claim 33, wherein upon release of a third short-time switching pulse the rear window wiper installation is switched off after termination of the wiping cycles.

35. Apparatus as claimed in any one of claims 31 to 34, wherein a wiper-washer programme for the rear window wiper installation is released by a long-time switching pulse.

36. Apparatus as claimed in claim 31, wherein upon release of a short-time switching pulse the rear window wiper installation is coupled to the windscreen wiper installation, wherein upon release of two switching pulses within a given time interval a wiper-washer programme is released, and wherein upon release of a further, possibly long-time switching pulse after the time interval the coupling between rear window wiper installation and windscreen wiper installation is released.

37. Apparatus as claimed in claim 31, wherein upon release of a first short-time switching pulse a wiper-washer programme of the rear window wiper installation is started.

38. Apparatus as claimed in any one of the preceding claims, wherein the programme controller is designed with integrated techniques especially by using microprocessors or microcomputers.

39. Apparatus for use with windows of motor vehicles substantially as herein described with reference to Fig. 1, Fig. 2, Fig.

3, Fig. 4, Figs. 5 and 6, Fig. 7 or Fig. 8 of the accompanying drawings.

40. A programme controller for use in a cleaning installation for windows of motor vehicles including a wiper motor, with or without a washing pump motor, and an operating switch which programme controller controls the various modes of operation of the wiper motor, with or without the washing pump motor, in dependence a switching signal supplied thereto by the operating switch in use thereof, the switching signal being a switching pulse or a switching pulse sequence, the programme controller being such that the mode of operation actuated thereby depends on at least one characteristic feature of the switching pulse or switching pulse sequence and/or upon the adjusted mode of operation when the switching pulse or switching pulse sequence is released and/or upon the time of release of the switching pulse or of the switching pulse sequence.

41. A programme controller substantially as herein described with reference to Fig. 1, Fig. 2, Fig. 3, Fig. 4, Figs. 5 and 6, Fig. 7, or Fig. 8 of the accompanying drawings.

42. A motor vehicle including a cleaning apparatus or a programme controller as claimed in any one of the preceding claims.