Electrical heating device for liquid in a windscreen wash system of a vehicle.

p0001The invention relates to an electric heater for windshield washer systems of vehicles with between at least one spray nozzle and a container for washing liquid flow space extending a fluid line, which is assigned a connectable to an electrical power source heating section.

p0002There are Electric water heaters for automobiles are known whose liquid line is formed as a conductive pipe; this is the same electric heater and heats the through-flowing washing liquid.

p0003Such heaters are to a very costly and complicated for others in their construction. In addition, it has been found that the liquid flowing through pipes do not have sufficient reliability.

p0004In consideration of that state of the art, the inventor set himself the aim to provide a heating device of the type mentioned, which is simple and also reliable in design and manufacturing. In addition to the heater remain inexpensive to manufacture and maintain.

p0005To achieve this object, that the Durchfdußraum the liquid line is provided with a Hinieitung and a kückleitung least one insulated heating wire whose two free ends are each connected to an outwardly projecting power connection for the power supply and insulated from the flow space. Preferred dimensions of that filament is doppeltrumig so arranged iw with axially parallel line sections, but can also be part of a coaxial current leadership, which a circuit the filament - surrounds the mantle - the interposition of an insulation.

p0006Here is the heating wire at least from one end of the liquid line protrude with a plug-in or push end, which preferably consists of a U-shaped exposed portion of the heating wire.

p0007According to another feature of the invention, the thrust end is made of a twisted portion of the heating wire or heating wire that with him and his isolation extensive mantle conductive material, making it particularly effective and stable.

p0008In the present invention, it is also that the thrust end of the heating wire - is which is preferably inserted in the formed of a tubular fluid line - extends from the latter and is led through an outlet connection of the container in the therein washing liquid; the filament is heated - after the terminal ends of the power connections have been connected to the alternator or a corresponding current source - the washing liquid then especially in the area of ​​the tank effluent, which disregard keeps freezing, at least in this area. In addition, the Heizdrahttrume the washing liquid in the hose heat. The already mentioned Doppeltrumigkeit has the advantage that always takes a back and a return of the heating current in. The tubing.

p0009Those thrust ends, so for example, the twists of the filament can be provided at all locations where the heating power is to be raised locally, not only in the container, but also in the field of liquid pump or especially directly at or in the nozzle. The thrust end of the heating wire can be easily inserted into the appropriate hose connector piece and then rests protected.

p0010It arises with this simple heating wire a very effective heating of all the flow space for the washing liquid forming individual units.

p0011In the invention, it is that the power connections or Heizstromkabel are connected within a Einspeisekörpers to the ends of the heating wire, which is ushered through hose connector piece that Einspeisekörpers in this.

p0012According to another feature of the invention the Einspeisekörper is provided with a flow space for the washing liquid, in the both ends open out the hose connector piece of Einspeisekörpers and adjacent to the recesses of Einspeisekörpers. In these recesses according to the invention resting the terminal ends of the power connections with the fixed mind free ends of the heating wire in sealing compound and are thus sufficiently insulated against the washing liquid without costly measures.

p0013As low e's has erwiese.n opposite define the two terminal ends of the heating wire on both sides of the flow space, the one strand of the filament passes. Also going from this flow space associated with the current connections Heizdrahtenden from. This results in the flow chamber itself at least three parallel sections of a heating wire. Of course, other configurations may be provided within the scope of the invention.

p0014The shape of Einspeisekörpers is not bound to the form described, for example, can also be a tee or a pressure valve.

p0015The heating wire may for example consist of a material which with increasing temperature its electrical resistance is increased so that the heating power decreases, so that so that a control can be effected.

p0016It is also possible to use an unregulated system in which only the touching of the filament components must be sufficiently temperature resistant.

p0017Also - controlled by a contained for example in Einspeisekörper temperature sensor - a control circuit are operated which switches the heating function of the temperature. Such a control circuit is able to be operated by the electrical resistance of the heating wire itself.

p0018The Einspeisekörper with the two of them outgoing tube sections or liquids can be used according to the invention either between the tank and pump or between the latter and the spray nozzle. Einspeisekörper preferably two, of which one of the spray nozzle and the other is adjacent the container is.

p0019According to the ends of the heating wire to Heizstromkabel the vehicle battery with the interposition of at least one switching relay are connected. If the vehicle engine is started, comes from the alternator the required voltage of about 12 volts, which draws that switching relay and closes the heating circuit; from the battery heating is released from about 4 amps.

p0020The power supply can by an - interrupted switch manually or by means of a temperature monitoring - preferably provided between relays and alternator.

p0021The required resistance of the heating wire can readily - are calculated to ensure that predetermined temperature values ​​are not exceeded even with short hose lines - from the wire length dependent.

p0022Particular embodiments own inventive value are described in claims 18 to 24; This device is intended for feed pumps of Waschfjüssingkeit which are grown directly on the container, or with the intake in these protrude. The inventive Einspeisekörper used herein is instead of the usual rubber sealing elements between the feed pump and container used so that a iw disc-shaped base body is held between these by rubber seals. From this base plate go out of coaxial sleeves, forming an annular space for the filament between them; this is passed through the annular space into a receiving space in the base plate and applied there to a to the power connector as well as, preferably with sealing compound insulated to the other.

p0023Further advantages, features and details of the invention will become apparent from the following description of preferred embodiments and from the drawing; this shows<ul><li>1 shows a section through a part of a motor vehicle not shown in the drawing.</li><li>. Fig. 2 is a detail of Figure 1 in section;</li><li>FIG. 3 shows the detail of Figure 2 in another embodiment.</li><li>FIG. 4 shows the longitudinal section through a Einspeisekörper;</li><li>Fig. 5 shows a further embodiment for Fig. 4;</li><li>Figure 6 is a schematized and partially sectioned plant in relation to the Figure 4 and 5 reduced reproduction..;</li><li>Fig. 7 is a circuit diagram;</li><li>Figure 8 shows a further Einspeisekörper in oblique view.</li><li>Figure 9 is a longitudinal section of FIG. 8. FIG.</li><li>Fig.10,12 sections through other containers;</li><li>Fiq. 11 an over 10 shows enlarged detail to another embodiment;</li><li>Fig. ¹³₁₄, opposite to _Fig. 1₂ shown enlarged 14 versions;</li></ul>

p0024In a sheet metal part 10 - for example, an engine compartment hood - a motor vehicle not shown in the drawing for reasons of clarity 1 is in a recess 11 of FIG the dowel-like plug-in foot 12 a -., Resting on a washer 13 -Spritzdüse 14 for a washing liquid Q so determined that the platform legs 12 outside molded barb ridges 15 of the sheet metal part inside 10_m rest. The mouth 14_m the spray nozzle 14 is directed to the neglected in Fig. 1 windshield of the motor vehicle towards.

p0025On the SchlauchanschJußstutzen 12_m formed free end of the plug foot 12 sits a hose line 20, in the tube chamber 21, a heating wire 31 with the outgoing line 29 and return line 30 runs. These sections 29, 30 of the filament 31 are connected endwise each twisted into a plug-in or push end 32, which is inserted into a channel 18 of the spray nozzle 14 and there - can be fixed - not reproduced.

p0026Also from the free end 19 of tubing 20 protrudes beyond a twisted thrust end 32 can be seen at the endwärtigen on the loop 33, that both Heizdrahtabschnitte 29, 30 parts of the U-shaped bent 33 at the heating wire are 31st The latter consists of a material with increasing temperature its electrical resistance is increased so that the heating power decreases, and is also coated with a heat-resistant insulating material.

p0027In the embodiment shown in Fig. 3, the heating wire 31 is_m out in an insulation 28, in turn, by a - surrounded the heating returning --Mantel 27th The latter is endwards dome-welded.

p0028In an embodiment not shown, a control circuit is provided which switches the heating current as a function of the temperature. The control circuit is optionally controlled by the temperature-dependent resistance of the heating wire or by a temperature sensor, for example, in a is m cuboid or cylindrical Einspeisekörper 40 as it 4 reproduces Fig..

p0029The Einspeisekörper 40 is connected coaxially protruding hose spigot 41 and besides these - fitted to each other in opposite directions -verlaufenden blind holes 42, which are filled with potting compound 43 as embedding for connecting ends 44 of electricity connection tabs 45,45.

p0030The Einspeisekörper 40 is integrated into the hose line 20 for the washing liquid Q. The adjacent tube ends are better because overview in Fig. 4 with 20_a and 20_b designated; Fig. 4 can moreover recognize also that the section single 29,30 parts of an. gen heating wire 31 are, the Un-isolated ends firmly into the terminal ends 44 of the current connection tabs 45,45_a sitting and from there respectively to form a - passing through openings 46 connecting between the Isolierräumen or blind holes 42 and the openings 39 of the tube connecting piece 41 flow space 47 - 34 loop opposite to the adjacent tube piece 20_a or 20_b are drawn from the other end, the push end 32 projects. At one of the thrust member 32 performs the forward line 29 and is at the endwärtigen loop 33 to the return line, which better clarity in FIG. 4 with 30_m is designated; this return line leads the current to the other push end 32 and leaves it permanently as a return line 30th

p0031In the Einspeisekörper 40 of FIG. 4, the portions 29, 30 parts of the sheathed heating wire 31, which in all areas within the tubing 20 with its portions 29, 30_m or 30_m, 30 or 29,30 is zweitrumig. m

p0032The Einspeisekörper 40_m . Fig 5 is composed of a cross-like form body 48 of the two coaxial hose tail 41 and the center thereof projecting at right angles connecting arms 49, in which - with outgoing lines 29 and return lines 30 connected - current connection tabs 45,45_r are isolated.

p0033The flow chamber 47 is here surrounded by a simple push tube 38, and between those hose tail 41 the outgoing lines 29 and return lines 30 are laid. The push tube 38 can also be neglected.

p0034Fig. Figure 6 shows a plant whose Einspeisekörper 40 is located between a discharge pump 24 and a container 51 for washing liquid Q, and both the feed pump 50 and to the container 51 through the tube pieces 20_a and 20_b connected is. In the washing liquid Q is a thrust end 32 of the heating wire 31 extends a. is not apparent that a push end 32 is inserted into the hose connector piece 41 of the feed pump 24th This plant has -the advantage that the washing liquid Q in the container 51 at Behälteraus flußstutzen 52 near the container bottom 53, the washing liquid Q at low temperatures keeps flowable when the heating wire 31 after joining his current connecting tongues₄₅, 45_r with Heizstromkabeln 59.60 a battery 58, a heating current of eg 4 amperes flows.

p0035In Fig. 7 runs from the positive terminal of the battery 58 a equipped with fuse 57 Heizstromkabel 59_a the tongue 54 of a switching relay 56, of the continued the Heizstromkabel 59 and a control line 55 is connected to the negative pole of the battery Heizstromkabel 60 of 58th That control line 55 is located opposite a connecting line 62 of the alternator 63 with switches 64th

p0036If the engine of the vehicle started, and 'are the alternator 63 itself from energy, then located at the terminal ₆1, a voltage of about 12 volts, so that the switching relay 56 energizes and closes the heating circuit. At the same time is released from the battery 58 via the switching relay 56 of the heating current of 4 amps. If the engine of the vehicle parked, the switching relay 56 interrupts to droop of the alternator 63 to heating current. The additional switch 64 can interrupt the entire flow guide described.

p0037In another embodiment, the circuit 57 containing the backup Heizstromkabel 59 _a the positive pole immediately introduce Heizstromkabel to the current terminal tabs 45 and the other power connection tongue 45, which is fixed to the tongue 54 of the relay 56th The tongue 54 is here compared to a contact of Heizstromkabels the negative pole of the battery, at this Heizstromkabel the control line is connected, the other hand on the relay ends opposite the lead 62nd In one embodiment, the plant is not shown in the container 51 at least a part of the hose line heizdrahtführenden is attached which holds the washing liquid Q total flowable.

p0038. Figure 8.9 shows a 70 Einspeisekörper particularly simple design; two pipe sections 90 penetrated at their centers discs 91 are held together by a coupling ring 92 - this connects the pipe sections 90 of the discs 91 and includes at each edge a pair of blind slots 93, 94. In a pair of blind slots 93 the two strands 29,30 are made of a piece of tubing 20_a stored in the other pair 94, the second piece of tubing 20_b, At 95 two strands 30 are soldered together, the strands 29 on the other hand led to the outside. It is not shown that this Einspeisekörper E is provided between its wheels 91 in an assembled state with a sealing compound, which also covers the end of the 95th

p0039The embodiment of a container 51 _a with filling opening 66 shown in FIG. 10 has a container wall 67 a niche-like indentation 68, in the bottom portion 69 has a recess 71 for a seal 72 surrounded intake 25 of a feed pump 24_a is provided. Above the latter is shown in Fig. 10, a pump motor 23 can be seen as well as a side of the feed pump 24_a Outgoing hose or pressure port 41 for connection of the hose line is not shown here 20 of the spray nozzle / n 14th

p0040In the embodiment of FIG. 11 is between 25 and intake pump wall 26 or between adjacent rubber seals 72, 72_m a Einspeisekörper 80 attached two base plates 78,79 and these formed concentric sleeves 75.76.

p0041The inner sleeve 75 - a diameter d_l here 6.8 mm - surrounds the intake port 25 to form a gap 81 of a width b of less than 0, 1 mm. The outer sleeve 76 has an inner diameter d to₂ of 8.4 mm. In the resultant between the sleeves 75,76 annulus 83 extend Heizdrahttrume 29,30, are fixed to the free ends of terminal ends 44 electricity connections to a casting 43rd The latter is located between the two base plates 78,79 and combines them into a uniform base disc 77th

p0042In the embodiments of FIGS. 13-14, the upper base plate 78 is provided with a raised edge of the bowl 88 in order to obtain improved heat supply to the pump chamber 22.

p0043Between the base plates 78,79 extend in FIG 13 power terminals 45 which are arranged on both sides of a PTC heating element 89th; the latter regulates a certain temperature, the heat output automatically to zero. The heating wire 31 is in the container 51_a designed.

p0044In the embodiment of FIG. 14, the heating cables are 29,30 wound around the intake manifold 25, whereby a higher heat output into the pump chamber 22 is carried out.