EP1334015A2

EP1334015A2 - Heatable washer system

Info

Publication number: EP1334015A2
Application number: EP01921177A
Authority: EP
Inventors: Joachim Zimmer
Original assignee: Robert Bosch GmbH
Current assignee: Robert Bosch GmbH
Priority date: 2000-05-10
Filing date: 2001-03-10
Publication date: 2003-08-13
Also published as: WO2001085500A2; US20020134857A1; WO2001085500A3; DE10022725A1; US6726122B2; KR100679187B1; KR20020059582A; JP2004501020A

Abstract

The invention relates to a heatable washer system (10) for vehicle windscreens, comprising at least one spray nozzle (16), which is supplied with water for washing by a pressure valve (38) and whose housing (40) is connected to a water pump (20, 58) by a water line (14). Said water pump conveys washing water from a reservoir (12) to the spray nozzle (16). A heating device (18) is situated in said reservoir (12). According to the invention, the water line (14) has two channels (26, 28), one (26) of which is connected to the pressure side of the water pump (20) and the other (28) of which is connected to the reservoir (12).

Description

Heated car wash

State of the art

The invention is based on a heatable washing system according to the preamble of claim 1.

Windshield washer systems for vehicles are usually used in conjunction with windshield wipers. They are activated when the moisture from precipitation is insufficient to clean the vehicle window. They contain a storage container, spray nozzles and a water pump,. the washing water, which may contain cleaning and anti-freezing agents, is conveyed with pressure from the storage container via water pipes to the spray nozzles. As a rule, ^{■ "} the spray nozzles are fastened to a part of a vehicle body, for example to a bonnet, a window frame or the like. In order to prevent the spray nozzles from freezing at temperatures below freezing, heating elements are integrated in the spray nozzles, which extend outside lying plugs are connected to a power supply. the Heize- ELEMENTS require a high relati Ferti ^'supply costs for the spray nozzles and a large installation effort to move around the electric wires and to contact the plug. Furthermore, evaporate the volatile Antigefriermit- The nozzle openings clog quickly and due to the residues.

It is already known from DE 198 15 171 AI to attach spray nozzles as additional components to the wiper blade, as a holding element, and thus to distribute the spray water directly onto the wiping area with a short jet length. Since the spray trated to an area near the wiper blade concen- ■ ^', and by the wiping motion in no time. is wiped off again, the view is through the applied

Splash water only hindered for a short time. A disadvantage of such systems, however, is that weather influences, in particular hail and extreme sun exposure, have a strong influence on the flexible parts of this arrangement, which are necessary for bridging the articulated areas between the wiper arm and the wiper blade. Furthermore, the spray nozzles and water pipes that are exposed to the airstream freeze quickly at temperatures below freezing if there is not enough anti-freezing agent mixed into the water. The frozen water pipes and spray nozzles can usually only be thawed out with great effort.

In order to prevent the spray nozzles attached to the wiper arm or wiper blade and the connected water line from freezing, a heating line is provided in the water line.

This is particularly important for wipers with larger wiper blades and multiple spray nozzles. In this case, the spray nozzles are arranged next to each other on the wiper blade at a certain distance and, like the connecting water pipe, are exposed to the ambient temperature.

In the earlier patent application DE 199 13 193 a washing plant is described, ^'the spray nozzles a continuous Have water channel, which has at its ends a coupling piece for further water supply. This leads to another spray nozzle or to the storage container. At the last spray nozzle, a cap is clipped onto the coupling piece, which closes the water channel. In order to be able to adapt the spray nozzles and the water pipes to the respective holding elements well, the coupling pieces of the spray nozzles have a straight or a cranked shape, as required.

The nozzle body of the spray nozzle is made of plastic and clipped into a housing. A connecting duct branches off from the continuous water duct of the spray nozzle and leads to a spray duct with a nozzle opening. When the water pump builds up pressure, washing water is pressed out of the reservoir through the system lines to the nozzle opening and then emerges through the nozzle opening. A variant provides a non-return valve so that no washing water runs on in the depressurized state, so that the lines are partially emptied. In this case, a membrane in the unpressurized ^'state closes the connecting channel. This can be close to the nozzle opening, so that only a small volume of water is stored between the membrane and the nozzle opening and can flow out or evaporate in an uncontrolled manner.

The membrane is designed as a rubber-elastic tubular membrane, which has beads at its ends. These are embedded in ring grooves in the nozzle body. When the washing water flows in through the connecting channel, an annular space on the circumference of the nozzle body is filled and the membrane is expanded. The membrane is supported on the outside of the housing and exposes the orifices of the connecting channel and the spray channel on the circumference of the nozzle body. There are also washing systems on the market in which a heating element is arranged in the storage container for the washing water. The heated washing water improves the cleaning power of the spray nozzles, but it cannot be prevented that the spray nozzles freeze during the breaks in operation without additional heating elements.

Advantages of the invention

According to the invention, the water line in a heatable washing system has two channels, one of which is connected to the pressure side of the water pump and the other to the reservoir and thereby to the suction side of the water pump. This creates an open circuit in which the water pump circulates the heated washing water, supplies the washing system with heat and thus prevents parts of the washing system from freezing in the event of frost without additional heating elements. All spray nozzles that are connected to the water line have pressure valves in front of their nozzle opening, which are expediently designed as check valves.

During the circulation operation, the pressure in the water line is below the opening pressure of the pressure valves. In order to operate the spray nozzle, the pressure in the water pipe is raised above the opening pressure of the pressure valves, so that washing water is sprayed through the open pressure relief valves and the nozzle openings on the vehicle window ^•. The spraying process is ended by reducing the pressure in the water pipe to the circulating pressure. •

The pressure in the water pipe can be generated in different ways. According to an embodiment of the invention, a two-stage water pump is provided. In the first stage, it generates the operating pressure for the recirculation mode during in the second stage it is designed for spray pressure. By switching from one level to another, the washing function is activated or deactivated. completed. Instead of a two-stage water pump, an infinitely variable one can also be used. This is expediently controlled depending on the temperature below the opening pressure of the pressure valve, so that the circulation capacity and thus the energy consumption of the water pump can be adapted to the respective requirements. Furthermore, it is avoided that wash water evaporates unnecessarily at the spray nozzles, as a result of which deposits can form.

With a constantly pumping water pump, the pressure in the water pipe can be controlled by a controllable pressure relief valve. This can basically be arranged on the suction side or on the pressure side of the water pump. If ^'the pressure limiting valve on the pressure side, it is convenient to an opening in the conveying direction, designed as a check valve. Pressure valve to be provided parallel to the pressure relief valve. If a spray pressure is activated at the pressure relief valve, the pressure valve opens in order to make larger delivery volumes available quickly.

Another possibility for pressure control is that an adjustable throttle is provided in the water pipe. Depending on the control of the choke, the flow rate increases through the water line, resulting in an arrangement in the feed to a pressure increase and in an arrangement in the ^'return to a pressure reduction. Temperature-dependent control of the circulation quantity is also possible here.

Regardless of the flow rate of the washing water, the heating element arranged in the storage container can be controlled as a function of the outside temperature be so that the temperature of the wash water is kept in a desired temperature range according to the outside temperature. It is sufficient if the washing water in the storage tank is only heated below -1-5 ° C.

All variants represent simple versions of a heatable washing system, since there are no additional heating lines in the water lines up to the spray nozzles. In addition, there is no need for additional contacts which are necessary for electrical heating elements arranged on the spray nozzles. Advantageously, electrical contact points are provided only on the storage container, which can optionally be used simultaneously for the heating device and the water pump.

In order to enable optimum heating of the complete system with low energy consumption, the invention provides that the washing system has a washing module with an integrated water pump, heating device and electronics, which closes input signals, such as the outside temperature or the actuation of the steering column switch processed an output signal for heating or changing the flow rate of the wash water. In a variant of the invention, the washing module is controlled by an external vehicle or wiper electronics. The proposed solution of a heatable washing system is to be used mainly in systems with spray nozzles integrated on the wiper arm or wiper blade. Due to the simple and variable design, it also works with spray nozzles positioned on the vehicle hood.

In order to enable flexible manufacture of a washing system according to the invention, according to one embodiment of the invention, dng provided to assemble the washing system from different functional parts, such as spray nozzles, connecting pieces, distributor elements, washing module and the like. Coupling pieces are provided at the connection points, which connect the parts of the water line tightly to one another. In a water pipe with two channels which are separated from each other by a common partition wall ^', the partition wall is formed in the connection area as a clutch by an extension of a partition wall in an end-face gap of the adjacent partition wall engages an adjacent functional part. • Absolute tightness between the channels is not necessary, since small short-circuit currents can be tolerated.

drawing

Further advantages result from the following description of the drawing. Exemplary embodiments of the invention are shown in the drawing. The drawing, the description and the claims contain numerous features in combination. The person skilled in the art will expediently also consider the features individually and combine them into useful further combinations.

Show it:

1 shows a schematic illustration of a heatable washing system, FIG. 2 _. a longitudinal section through two by means of a

3, a schematic representation of a storage container, Fig. 4- ^• 5 variants to Fig. 3>

Fig. 6 shows a schematic illustration of a washing module,

Fig. 7 shows a variant of FIG. 6,

Fig. 8 shows a variant of FIG. 1.

Description of the embodiments

A washing system 10 for vehicle windows consists of at least one spray nozzle 16, which is connected to a storage container 12 via a water pipe 14 (FIG. 1). The washing water of the washing system 10 is located in the storage container 12 and is heated by a heating device 18 if necessary. A water pump 20 conveys wash water from the reservoir 12 via the water line 14 to the spray nozzle 16. The water line 14 has two channels 26 and 28, the channel 26 being connected to the pressure side of the water pump 14 and the channel 28 leading into the reservoir 12.

Wash water drawn in by the water pump 20 is conveyed via the channel 26 to the spray nozzle 16 and, as long as it does not escape into the open through the nozzle opening 48 of the spray nozzle 16, flows back via the channel 28 into the reservoir 12.

In cycle operation, the wash water is pumped through the water line 14 at an operating pressure which is set by a pressure relief valve 22 arranged in the channel 26. However, so that the washing water can be sprayed through the nozzle opening 48 of the spray nozzle 16, the pressure in the water line 14 is increased to a spray pressure. The increased pressure opens pressure valves that are used as check valves a hose membrane 38 and are arranged in front of the spray nozzles 16 (FIG. 2).

In the embodiment of FIG. 1, the water pump 20 is arranged a controllable pressure relief valve ^'22 on the pressure side, which adjusts the respective pressure level. In parallel to the pressure relief valve 22, a pressure valve in the form of a check valve 24 is provided, which releases a larger flow cross section when the spray pressure is reached.

The spray nozzle 16 consists of a housing 40 which is detachably connected to the water line 14 via a coupling piece 42 (FIG. 2). The housing 40 is made of plastic and surrounds a water channel 36, from which a connecting channel 44 branches off, which leads to a spray channel 46 with a nozzle opening 48. Moreover, the spray nozzle 16 a .Schlauchmembran 38 which acts as a pressure relief valve and non-return valve, by a connection between a connecting channel 44 and a spray conduit 46 is when a predetermined pressure-free ^'. If several spray nozzles 16 are used, they are each connected by a connecting piece 34 of the water line 14. Just like the water line 14, the water channel 36 of the spray nozzle 16 also has two channels 26 and 28 and the partition walls 30 arranged between the channels 26 and 28 are connected to one another in the area of the coupling piece 42 by a coupling 32. The wash water thus flows back from the reservoir 12 in the channel 26 in the direction of the arrow 50 to the last spray nozzle 16 and then in the channel 28 in the direction of the arrow 52 into the reservoir 12. The connecting channel 44 of the spray nozzle 16 is filled with wash water up to the hose membrane 38. Only in the washing mode, when there is a higher pressure in the washing system 10, the hose membrane 38 widens and some the wash water passes through the injection channel 46 to the ^due-• senöffnung 48 and. ^' is then sprayed over the vehicle window.

In standby mode, the water pump 20 constantly circulates washing water in the washing system 10, so that the water pipes 14 and the spray nozzles 16 are heated by the washing water. For this purpose, the washing water is heated in an embodiment of the invention by a continuously adjustable heating device 54 arranged in the storage container 12 (FIG. 3). The heating device 54 is expediently controlled as a function of temperature. During the circulation process, heat is exchanged with the surrounding components and the cooled washing water flowing back into the storage container 12 is heated again.

4 shows a variant, wherein the heat input into the washing system 10 takes place via a variable flow rate of the washing water. According to this variant, the temperature of the washing water in the storage container 12 is kept constant in a certain range, heating from a temperature of. for example, less than + 5 ° C is provided. At low ambient temperatures, the flow rate of the ^• washing water in the washing system 10 is increased and thus more heat is also released to the surrounding components. Here, a throttle 56 arranged after the water pump 20 or a continuously variable water pump 58, as shown in FIG. 5, controls the flow rate.

The washing installation 10 expediently has a washing module

60 with an integrated water pump 20 or 58, a heating device 18 or 54 and control electronics 66 (FIG.

6). The integrated control electronics 66 is able to process signals 62, such as the ambient temperature or a signal from the steering column switch, - to process an output signal 64 for the heat flow in the washing water circuit of the washing system 10. In one variant, the washing module 60 receives a signal from external control electronics 68, ^" which can be, for example, vehicle or wiper electronics (FIG. 7).

Enable both variants of the control electronics. moreover, in a simple manner, a continuous or a clocked control, so that with a constant control, for example, the speed of the water pump 58 is increased at a low ambient temperature, while with a clocked control, the operating time of the water pump 58 is varied in this temperature range.

The water line 14 of the washing system 10 preferably consists of various system components, such as nozzle systems 72, connecting pieces 34 and distributor elements 74, which are connected to one another at the connecting points by coupling pieces 70. are (Fig. 8). The connection . the water line 14 to the reservoir 12 is also formed by a coupling piece 70. Due to the large number of system components 34, 72, 74 and their variable assembly to form an overall system as a 'washing system 10, use is particularly useful in systems with spray nozzles integrated in the wiper arm or in the wiper blade - 16 but also with spray nozzles 16 positioned on the vehicle hood.

Claims

Expectations

1. Heated washing system (10) for vehicle windows with at least one spray nozzle (16) which is supplied with washing water via a pressure valve (38) and the housing (40) of which is connected to a water pump (20, 58) via a water pipe (14) which conveys washing water from a storage container (12) to the spray nozzle (16), a heating device (18) being arranged in the storage container (12), characterized in that the water line (14) has two channels (26, 28) from which one (26) is connected to the pressure side of the water pump ^' (20) and the other (28) to the reservoir (12).

2. Washing system (10) according to claim 1, characterized in that the water pump (20, 58) in a first operating state circulates the washing water via the water line (14), while in a second operating state the pressure in the

Water pipe is increased so far that the pressure valve (38) opens towards the spray nozzle (16).

3. Washing system (10) according to claim 2, characterized in that the water pump (58) has two stages or. ^{• is} infinitely variable.

4 / washing system (10) according to any one of the preceding claims, characterized in that the pressure in the water line (14) is controlled by a pressure relief valve (22) on the pressure side of the water pump (20). - ^' •

5. washing system (10) according to claim 4, characterized in that the spray pressure controlled by an external signal opens a check valve (24) which is arranged on the pressure side of the water pump (20) and parallel to the pressure relief valve (22) ,

6. Washing system (10) according to one of the preceding claims, characterized in that the water line (14) consists of connecting pieces (34) and of distributor elements (74) to which at least one nozzle system (40, 72) is connected and that coupling pieces (42, 70) are present at the connection points of the water pipe (14) and at the connection to the water pump (20, 58) or to the storage container (12). , ,

7. washing system (10) according to claim 6, characterized in that between the channels (26, 28) of the water pipe ^■

(14) and the water channel (36) partition walls (30) are provided which are connected to one another in the area of the coupling pieces (42, 70) by a coupling (32).

8. Washing system (10). according to one of the preceding claims, characterized in that a check valve (24) is integrated in the spray nozzle (16), which also serves as a pressure valve.

9. washing system (10) according to claim 8, characterized in that the check valve (24) has a hose membrane • (38).

10. Washing system (10) according to one of the preceding claims, characterized in that the heating device (54) in the storage container (12) is controlled depending on the outside temperature.

11. Washing system (10) according to ^' one of the preceding claims, characterized in that a. Circulation amount of the washing water in the washing system (10) is controlled as a function of temperature.

12. Washing system (10) according to claim 11, characterized in that the flow rate of the washing water is changed by the continuously variable water pump (58) ^' .

13. Washing system (10) according to claim 11, characterized in that a controllable throttle in the water pipe (14)

(56) is arranged after the water pump (20) /

14. Washing system (10) according to one of the preceding claims, characterized in that the washing system (10) has a washing module (60) with an integrated water pump (20, 58) _r heating device (18, 54) and electronics (66) which have input signals (62) processed in an output signal (64) for the ^■ • ärmestrom in the washing water circuit.

15. Washing system (10) according to one of the preceding claims, characterized in that the washing system (10) is a washing module (60) with an integrated • water pump (20, 58) and Has heating device (18, 54) which is controlled by an external vehicle or wiper electronics (68).