DE19858635A1 - Screen washing system for motor vehicle with storage container for washing liquid from which this is suppliable using at least one controllable pump to washing nozzles across hose lines - Google Patents

Abstract

The refilling is controlled in the manner of a two point control, with a filling level detection with at least one filing level sensor (11,12) at the storage continue (2) as an actual value transmitter. Which transmits a filling level maximum signal with a full storage container and a filling level minimum signal with and under a determined low emptying degree of the storage container. A control valve (7) is controllable as an adjusting element, in the open and closed settings. A rain sensor (9) provides a rain or a non-rain signal. A control unit (14), is provided, at which are connected, the filling level sensor (11,12), the rain sensor and the valve with its signal lines (15,16,18) and control lines (19). So that the control valve is controlled only its open setting, if at the control unit, at the same time lie the signals rain signal and filling level min. signal, and with another signal combination the control valve is controlled in its closed setting.

Description

The invention relates to a windscreen washer system for motor vehicles according to the preamble of claim 1.

Generally known windshield washer systems for motor vehicles have a storage container for the washing liquid, from which it is by means of at least one controllable pump Wash nozzles can be fed via hose lines. These washing jets can be one Front window, a rear window or headlights. The control of the Pump is usually done by the driver using a switch.

The washing liquid is refilled in a complex and convenient manner from Hand mostly in an unsatisfactory manner only when the empty storage container Washing function is no longer available. To ensure the safety of the refill improve, level sensors are also known, the one the vehicle driver Signal the minimum fill level using a warning lamp.

There are also windscreen washer systems with an automatic refill device known (GB 22 76 129 A; DE 43 16 345 A1) with a collecting device for rainwater, from which rainwater can be conducted to the storage container via a refill line refill automatically when it rains. In similar windscreen washer systems (DE 43 30 724 A1; DE 41 01 820 A1) a dirt filter is also used in the refill line in order to Wash liquid from contamination and thus the wash nozzles from clogging protect.

The above windscreen washer systems with automatic refill are open systems with an overflow on the storage tank, over the excess, supplied rainwater can drain through the reservoir again. This will be disadvantageous Washing liquid additives, such as intensive cleaners or antifreeze, which the Wash liquid is usually added with the overflowing rainwater washed out of the reservoir. Such a flood of expensive  Washing liquid additives are not acceptable. In particular, during a frost period after washing out an anti-freeze, freeze the windscreen washer and thus inoperable.

In order to create an improvement here, it is known, with such Windshield washer to provide a float valve on the reservoir (DE 297 05 137 U1), which is in a storage container full of rainwater closes. So that is the washing out of a washing liquid additive, which is in the Prevented reservoir. However, one takes place each time it rains immediate refill, especially from a minimal level, an intolerable dilution, so that z. B. after a windscreen washer sharp decrease in antifreeze concentration can freeze.

Next is such a windshield washer with an automatic Rainwater refill and a level limit as well as with a control unit known (WO 96/22203), with which an intensive cleaning agent by means of controlled pumps and / or an anti-freeze agent can be supplied to the washing liquid in the storage container. The concentration of these washing liquid additives is determined by sensors in the Washer fluid determined and depending on a specific control unit Refill carried out. With such an arrangement takes place in the automatic Refill process with rainwater also a partial washout of Washing liquid additives, which, however, in a complex manner due to cost-intensive Additional devices can be readjusted again.

The object of the invention is, in contrast, the function of a generic To improve windscreen washer system for motor vehicles.

This object is achieved with the features of claim 1.

According to claim 1, the refill is controlled in the manner of a two-point control. For this purpose, a fill level detection with at least one fill level sensor is on the storage container provided as an actual value transmitter, the "fill level maximum signal" when the reservoir is full and a "fill level minimum signal" at and below a certain, relatively low Emptying level of the storage container. Next is a valve in the refill line as Used actuator that is controllable in an open position and in a closed position. In addition, a rain sensor is provided that detects a "rain signal" or a "non-rain Signal "emits. Such a rain sensor can possibly be present on the vehicle anyway  and for example for an automatic control of a sunroof when it rains deliver appropriate control signal.

The fill level detection with the at least one fill level sensor, the rain sensor and the valve are with their signal lines or control lines to a control unit connected. This control device is preferably not an independent device but with its function integrated into an existing vehicle control unit. The control takes place in such a way that the valve is only controlled in its open position when on Control unit at the same time the signals "rain signal" and "fill level minimal signal". With all other signal combinations, the valve remains in its closed position controlled.

This ensures that the storage container with the washing liquid and possibly with a certain concentration of washing liquid additives is emptied as long as until the "minimum level signal" is given. A previous dilution or Flushing with washing liquid additives does not take place even when it is raining and thus a rainwater refill would be possible.

The windshield washer system is thus advantageously closed and in normal operation only open when a refill from a minimal level to a maximum level is achieved by rainwater, with all intermediate levels the valve and thus the system are closed both when it is raining and when it is not raining are. This in particular also reduces the risk of contamination of the system by constantly supplied rainwater is reduced, even in the event that a dirt filter is provided.

A warning lamp is also preferably switched on by the fill level minimal signal The driver's field of vision is activated. Additionally or alternatively, an acoustic Warning, for example by means of a signal tone. If necessary, the Vehicle drivers when the reservoir for an automatic refill with Rainwater is ready. The vehicle driver can then take place automatically Refill process decide whether a washing liquid additive should be added if necessary.

In an advantageous development, such a refilling process for one Washing liquid additive simple, functional and additive-saving automatable. It is proposed that the reservoir for the washing liquid with a Container for cleaning liquid and / or an antifreeze agent through a  Connection line is connected to a pump controllable by the control unit. After the valve is controlled from the open position to the closed position, i. H. after a complete refill of the storage container with rainwater, the pump is switched off to control a predetermined, specific amount of cleaning fluid and / or antifreeze. By adding a certain amount to the completely filled storage container is a certain, if applicable, predetermined concentration of Detergent additive achieved, which is until the emptying and the response of the "Level minimal signal" and possibly not changed below. The predetermined amount can control technology by a certain predetermined number of strokes Piston pump or possibly specified by the control unit by a specific pump runtime become.

The invention is explained with the aid of a drawing.

The single figure schematically shows a windshield washer system 1 with a storage container 2 for washing liquid 3 , wherein generally known hose lines connected to it, a controllable pump and washing nozzles in front of a front window 4 of a motor vehicle have been omitted for clarity.

The windscreen washer system 1 also has an automatically functioning rainwater refill device 5 with a collecting device for rainwater 20 in the form of a collecting channel 6 , a control valve 7 and a refill line 8 between the collecting channel 6 via the control valve 7 to the reservoir 2 . A dirt filter 21 is switched on in the refill line 8 .

In addition, a rain sensor 9 is provided, which is attached here in the upper region of the windshield 4 . A fill level detection in the manner of a riser pipe 10 is attached to the reservoir 2 with a lower fill level sensor 11 and an upper fill level sensor 12 , which are activated in a manner known per se by a float ball 13 in the riser pipe 10 . When the reservoir 2 is full, the upper level sensor 12 emits a “maximum level signal” to a control unit 14 via a signal line 15 . Correspondingly, the lower fill level sensor 11 sends a “fill level minimal signal” to the control unit 14 via a signal line 16 at and below a correspondingly predefined degree of emptying of the storage container. Depending on the circumstances and the desired automatic refill, this signal can already respond to approximately 1/4 of the container content. In addition, this “fill level minimal signal” can be fed to a warning lamp (not shown) in the field of vision of a vehicle driver. An overflow valve ( 17 ) can also be arranged on the storage container 2 .

A signal line 18 also leads from the rain sensor 9 to the control unit 14 , via which either a "rain signal" or "non-rain signal" is present. A control line 19 also leads from the control unit 14 to the control valve 7 .

The arrangement shown has the following function under the following conditions:

• 1. The rain sensor 9 gives the information "rain signal" and the upper fill level sensor 12 gives the information for a full reservoir 2 with the signal "fill level maximum signal" - the control unit 14 holds the control valve 7 in the closed position.
• 2. The rain sensor 9 gives the information "rain signal" and the lower fill level sensor 11 signals an (almost) empty reservoir 2 with a "fill level minimal signal" - the control device 14 controls the control valve 7 into its open position.
• 3. The rain sensor 9 gives the information “non-rain” and the lower fill level sensor 11 signals an (almost) empty reservoir 2 with a “fill level minimal signal” - the control device 14 holds the control valve 7 in the closed position.
• 4. The rain sensor 9 gives the information "non-rain" and the upper fill level sensor 12 signals a full reservoir 2 with a "fill level maximum signal" - the control unit 14 holds the control valve 7 in the closed position.

For this purpose, a solenoid valve that is spring-biased in the closed position is preferably used as the control valve 7 .

REFERENCE SIGN LIST

1

Windshield washer

2nd

Storage container

3rd

Washing liquid

4th

Windscreen

5

Rainwater refill facility

6

Collecting channel

7

Control valve

8th

Refill line

9

rain sensor

10th

Riser pipe

11

lower level sensor

12th

upper level sensor

13

Float ball

14

Control unit

15

Signal line

16

Signal line

17th

Overflow valve

18th

Signal line

19th

Control line

20th

Rainwater

21

Dirt filter

22

Mixer for cleaning agents

Claims (5)

1. windscreen washer system for motor vehicles,
with a storage container ( 2 ) for a washing liquid ( 3 ), from which the washing nozzles can be supplied via at least one controllable pump via hose lines,
with a collecting device ( 6 ) for rainwater ( 20 ), from which rainwater can be conducted into the storage container ( 2 ) via a refill line ( 8 ) in order to refill it automatically when it rains,
characterized in that the refill is controlled in the manner of a two-point control,
with a fill level detection with at least one fill level sensor ( 11 , 12 ) on the reservoir ( 2 ) as an actual value transmitter, which generates a "fill level maximum signal" when the reservoir is full ( 2 ) and a "fill level minimum signal" at and below a certain level, emits a low degree of emptying of the storage container ( 2 ),
with a control valve ( 7 ) in the refill line ( 8 ) as an actuator, which can be controlled into an open position and a closed position,
with a rain sensor ( 9 ) which emits a "rain signal" or a "non-rain signal",
with a control device ( 14 ) to which the level detection with the at least one level sensor ( 11 , 12 ), the rain sensor ( 9 ) and the valve ( 7 ) with their signal lines ( 15 , 16 , 18 ) and control lines ( 19 ) are connected and that the control valve ( 7 ) is thus only controlled in its open position when the signals "rain signal" and "level-minimal signal" are present at the control unit ( 14 ) and that the control valve is controlled in its closed position with a different signal combination . 2. windscreen washer system according to claim 2, characterized, that with the "fill level minimal signal" a warning lamp in the field of view Vehicle drivers and / or an acoustic warning signal can be activated. 3. windscreen washer system according to claim 1 or claim 2, characterized in that
that the storage container ( 2 ) for the washing liquid ( 3 ) is connected to a container for cleaning liquid and / or an anti-freeze by a connecting line with a pump which can be controlled by the control unit ( 14 ),
that the pump for metering a certain amount of cleaning fluid and / or antifreeze is controlled after the control valve ( 7 ) is controlled from the open position after a complete refill to the closed position. 4. Windscreen washer system according to one of claims 1 to 3, characterized in that a dirt filter ( 21 ) is arranged in the refill line ( 8 ). 5. windscreen washer system according to one of claims 1 to 4, characterized, that the washer nozzles in front of the windscreen and / or rear window and / or the Headlights are arranged.