DE3323004A1 - Screen wiper system, in particular for motor vehicles - Google Patents

Abstract

The invention relates to a screen wiper system, in particular for motor vehicles, which has a wiper arm, provided with a wiper blade, and a rinsing agent duct which participates in the wiping movement of the screen wiper and next to which there is provided on both sides a heating agent duct which is connected in a thermally conductive fashion to the rinsing agent duct, outlet openings facing towards the screen being present in the rinsing agent duct, and the rinsing agent duct being connected to a rinsing agent feed, and the heating agent duct being connected to a heating agent feed. According to the invention, the wiper arm is formed by a basic unit embracing the rinsing agent duct and the heating agent ducts.

Description

Daimler-Benz Aktienge.se 1. Lschaft. . ' Daim 14 41-4 / 4 Stuttgart-Untertürkheini ¹ ^ - ^{June 1983}

"Windshield wiper system, especially for motor vehicles"

The invention relates to a windshield wiper system, in particular for motor vehicles. Which has a wiper blade provided wiper arm and one on the wiping movement of the windshield wiper participating flushing medium channel, next to

• 5 which a heating medium channel is provided on both sides, the is in heat-conducting connection with the flushing medium channel, wherein - in the flushing medium channel, outlet openings facing the disk are provided are present, and. wherein the flushing medium channel to a flushing medium supply and the Heizme.diumkanal a heating medium supply is connected.

One such windshield wiper system is DE-OS 3.1 34 already known.

The effectiveness of a window wash is here compared to a conventional stationary nozzle spraying from greater Removal is more intensive, but the wiping process itself is just as important for cleaning a window. An essential criterion for its efficiency is the exact one

■ - * - Daim 14 414/4

■ ι-

3. Windshield wiper system according to claim 1 or 2, characterized, that the wiper blade (3) is articulated on the wiper arm (2) in a manner known per se so that it can only be connected centrally and detachably is.

4. Windshield wiper system according to claim 3, characterized in that that the wiper arm (2) at least essentially corresponds to the longitudinal extent of the wiper blade (3) the articulation point of the same protrudes.

5. Windshield wiper system according to one or more of the preceding Expectations,

characterized in that the outlet openings (8) of the flushing medium channel (7) are equipped with adjustable nozzles (6).

- ^ - Since in 14 4 14/4

Λ-

Compliance with a constant over the length of the wiper lip Contact pressure of the same. With the known wiper element, a sufficiently uniform contact pressure can at best be completely flat panes can be achieved. It is suitable for the curved panes commonly used in contemporary automobile construction themselves in any way.

. In addition to the wipe-wash process, the well-known Wischorgah should also be able to serve as a means of de-icing. This circumstance requires that the contact pressure that the wiper member must experience must be significantly higher than "with other wiping systems. The The wiper lip, which has to absorb the contact pressure as a support member, is therefore subject to extremely high wear, so that the anyway short service life of the wiper lip is further reduced.

A further problem arises from the

• Dimensions of this wiper element. By the opposite of the usual The tendency to lift off the wiper blades is significantly higher upstream area of the wiping element is very pronounced at high driving speeds.

The invention is based on the object of a windshield wiper system of the type corresponding to the preamble of claim 1 so that the wiper blade even with curved Windows ensures a sufficiently uniform contact pressure over the entire length of the wiper lip.

The. The solution to this problem according to the invention is the subject matter of the characterizing features of claim 1.

- & - As in 14 4 14/4 ■

-b ■

. 33230G4

Claim 2 provides a closed circuit for the heating medium. This can come from a circulating medium that is circulated, or a heat pipe or. like. exist. Due to the increased heat content of liquid heating _media% to gaseous come this preferred for use.

The main advantage of such closed systems is to be seen in the fact that a filling amount of the heating medium in is in constant circulation, so there is no need for refilling.

In the embodiment according to claim 3, a wiper blade conventional design are used. This means that the function can be easily replaced proven component that can be manufactured inexpensively as a mass-produced item is fully preserved.

Claim 4 includes a special design of the wiper poor. This is to be regarded as advantageous in that a (windscreen spraying with a constant spray path over the entire length the wiper blade can be done.

The use of adjustable nozzles according to claim 5 is at Windshield wiper systems are preferably used when the wiper arm or the wiper blade over part of the length completely covered, so that a direct spraying of the pane perpendicular to the pane surface is not possible. Here-can the nozzles are set so that the spray jet immediately hits the window next to the wiper blade and thus the Spray path remains as short as possible.

-T- - ■: - Daim 14 414/4

The following is an exemplary embodiment for an inventive Windshield wiper system explained with reference to the drawing, namely shows

Fig. 1 is a vertical section through the windshield of a motor vehicle by a window

wiper is applied, and

Fig. 2 is a section along the line II-II in Fig. 1.

A windshield wiper 1 comprises an oscillatingly drivable wiper arm 2, on whose wiper rod 2a a wiper blade 3 in is conventionally hinged centrally and releasably connectable. A wiper lip 3a of the wiper blade 3 lies on the whole Length on a curved front pane 4, of which only the area serving as a wiped field is shown. The wiper blade 3 is pressed resiliently against the outer surface of the front disk 4 by the action of a helical spring 5 and is from this active position by changing the direction of pull of the helical spring 5 in a known manner in a Withdrawal transferable. The wiper rod 2a is the longitudinal extent of the wiper blade 3 over the Deflection point extended to the wiper blade 3 and is located. ' about the same distance from the disc 4 as the lower one Area of the wiper rod 2a. Spray nozzles 6 are arranged on the broad side of the wiper rod 2a facing towards the window, 'which serve to spray the windshield with a flushing medium.

The supply of rinsing liquid to the nozzles 6 takes place, as • can be seen from Fig. 2, through a flushing medium channel 7, which is in communication with the nozzles 6 via passage openings 8.

- · Κ · - On in M · 1 ΙΊ / -1

There is a heating medium channel on both sides of the flushing medium channel 7 9 provided through which a heating medium is passed. The walls of the flushing medium channel 7 and the heating medium channels 9 are made in one piece and in their entirety form the wiper rod 2a. Through this One piece is a good prerequisite for an optimal heat transfer between the heating medium channels 9 and the flushing medium channel 7, which is aimed at here. The clear cross-sections of the. Flushing medium channel 7 or the Heating medium channels 9 can have not only circular, but also other geometric surfaces, but they should on the other hand, in their entirety, form a one-piece wiper rod. At the lower end of the wiper rod 2a are the medium channels 7 and 9 are connected to flexible hose lines which are led out of the wiper arm 2 and lead in the not shown front end of the vehicle. The flushing medium line 7a is here with a Reservoir in connection, from which the flushing medium is pressed to the spray nozzle 6 by means of a pressure source and thus' can be sprayed onto the disc 4. The heating medium lines 9a are also provided with a liquid reservoir connected, in which the heating medium, which preferably consists of an anti-freeze liquid, can be heated. This heating process can, for example, by means of an electrical resistance heater or by using the exhaust gas heat of an internal combustion engine take place by means of a heat exchanger. The heated heating medium is passed through one of the heating medium channels 9 pumped, which in turn has at the free end of the wiper rod 2a connection to the second heating medium channel 9, so that a 'A closed circuit is created in which one of the heating medium channels 9 acts as a flow and the second heating medium channel 9 acts as a return.

- -9-- Daim 14 414/4

In this case, so much heat can be supplied to the flushing medium channel 7
that the spray nozzles 6 can be prevented from freezing over at winter temperatures, the spray distance to the windshield 4 being small, and a sufficiently uniform contact pressure of the wiper blade even when the wiper blade is curved
Panes over the entire length of the wiper lip.
is ensured.

Claims (2)

Daimler-Benz AkL iengese 1 1 -, <h. I'L Then 14 Ί 11-4 Stuttgart-Untertürkheiui - ^. > J "" i '1 ^ claims 1. Windshield wiper system, especially for motor vehicles, via a wiper arm provided with a wiper blade and one at the wiping movement of the Sehe i benwi sobers participating flushing medium channel, in addition to which a heating medium channel is provided on both sides, which connects to the flushing medium channel is in heat-conducting connection, has, wherein in the flushing medium channel facing outlet openings are present, and wherein the flushing medium channel to a Flushing medium supply and the heating medium duct is connected to a heating medium supply, characterized,' that-the wiper arm (2) from one of the flushing medium channel. (7) and the structural unit comprising the heating medium channels (9) is formed. 2. Windshield wiper system according to claim 1, thereby g e k e η η ζ e i c h η e 't, that the heating medium channels (9) with the heating medium supply are connected to a closed circuit.