EP2720914A1

EP2720914A1 - Wiper blade for cleaning windows, in particular of motor vehicles

Info

Publication number: EP2720914A1
Application number: EP12717286.4A
Authority: EP
Inventors: Geert Jans; Peter Saevels; Guido Tuyls; Martin Kipfmueller; Hubert Verelst; Eric Windmolders; Jan Van Hoye; Marcello Bubba; Hervé Bratec; Jochen Weidlich
Original assignee: Robert Bosch GmbH
Current assignee: Robert Bosch GmbH
Priority date: 2011-06-14
Filing date: 2012-04-26
Publication date: 2014-04-23
Also published as: DE102011077483A1; CN103608222A; CN103608222B; WO2012171698A1

Abstract

The invention relates to a wiper blade (10) and to a method for producing a wiper blade (10) for wiping windows, in particular motor vehicle windows, having a supporting element (12) for holding a wiper strip (14) to which a connection apparatus (20) is attached, said connection apparatus having a wiper-blade-side part (15) with claw-like holders (34, 36) which engage around the supporting element (12) at least in regions. The invention proposes that the wiper-blade-side part (15) of the connection apparatus (20) is attached to the supporting element (12) by way of in each case one attachment point (70) for each spring rail (28, 30).

Description

Description title

Wiper blade for cleaning windows, especially of motor vehicles. State of the art

When wiper blades referred to in the preamble of claim 1, the support element over the entire swept by the wiper blade wiping field should ensure the most uniform distribution of the wiper blade outgoing wiper blade contact pressure on the disc. By a corresponding curvature of the unloaded support member - so if the wiper blade is not applied to the disc - the ends of the wiper blade fully applied to the disc wiper blade are loaded by the then tensioned support member to the disc, even if the radii of curvature of spherical curved vehicle windows change at each wiper position. The curvature of the wiper blade must therefore be slightly stronger than that in the wiping field at the wiping

Disc measured strongest curvature. On the support element, a connecting device is attached, via which the connection is made to the wiper arm.

From EP 0914269 Bl it is known, the connection device by means of a

To attach welded joint on the support element. For this purpose, the either of metal or a plastic existing wiper blade-side connecting element is applied or pushed onto the support member and connected by means of a resistance welding in the case of a metal fastener or by means of an ultrasonic welding in the case of a plastic fastener cohesively with the support member. This welded joint is exposed to extreme conditions in everyday life and has to withstand high torques and vibrations even in different weather conditions. Particularly in the case of the wiper blades produced in large quantities, the welded connection places high quality demands on the process management.

Advantages of the invention

A wiper blade with the features of the main claim has the advantage that the

Spring rails only at one point fixed to the wiper blade side of the Connecting device are connected. Voltages, in particular shear stresses between spring rail and wiper blade-side part, which result due to the change in the curvature of the spring rails in the course of the wiping movement and act between the fixed points, are completely avoided. Even with tight tolerances, it allows the spring rail to move relative to the wiper blade side part to just this one point. The attachment point can be arranged on one side, for example on the convex upper or the concave lower band side, but it is also possible that the attachment point on the two opposite

Band sides is equally arranged. Even if the attachment point a

Connection between the wiper blade side part and the spring rail, which extends from the upper belt surface on the narrow side to the lower belt surface, the invention is not abandoned, because the effect that move the spring bar to a point opposite the wiper blade side part of the connecting device can, also exists here. It is clear that the term attachment point should not be understood as a mathematically one-dimensional point but as a technically conditioned, small locally restricted surface in contrast to a line-like or planar one

Connection.

The features listed in the dependent claims are positive

Further developments of the wiper blade according to the invention. Thus, the power flow can be optimized, starting from the wiper arm on the wiper blade side part in the spring rails, when the one attachment point per spring rail centrally, in particular in a region below the axis and / or axle, is arranged. Depending on the extent of the axle or axle, the attachment point may be within the vertical projection of the axle or axle or even extend beyond. The introduced force acts perpendicularly from the wiper arm starting directly to the attachment point of each spring rail and thereby avoids additional moments or stresses.

If the attachment point is arranged eccentrically with respect to the longitudinal extension of the wiper blade side part, in particular outside a region below the axle and / or axle retainer, it is possible for a part of the force to be targeted into a part of the shaft

Wischblatts, for example, to the outer circle of the wiping movement, initiated. Although these are only very small force differences, but can affect a wiping result under different conditions. If the one attachment point per spring rail is a melting point, it can be generated simply by heat introduction or ultrasound introduction.

Is the one attachment point per spring rail a melting point, he can directly the material of the wiper blade side part with the material of the spring rail or a

Connect the coating of the spring rail. The material can only be light

be melted, so that more of an adhesive effect arises, which is preferable in particular for different materials. But it is also a complete one

Melting and mixing with the same materials possible, what larger

Holding forces generated.

The invention also relates to a method for producing a wiper blade, in which the wiper blade-side of the connection device is fastened to the support element via an attachment point per spring rail. This one attachment point can be selectively introduced and monitored during insertion. This can improve the quality of the

Attachment point can be increased.

Very easily, the attachment point can then bring in, if this means

Ultrasonic welding happens. This technique is very well manageable, especially for connections between plastics.

A further increase in quality of the attachment point is achieved if its production takes place in several temporal stages. The stages can run sequentially one after the other or overlap in time. In the optimal case, the flow of energy is controlled in one step and the process path in the other step. In particular, tolerances can be compensated for.

drawing

1 shows a wiper blade according to the invention in a perspective illustration with wiper arm and dash-dotted line indicated surface of a windscreen, FIG. 2 is a view according to II-II in FIG. 1, FIG. 3 is a schematic representation of the view according to FIG. 2 4 shows a schematic view in the viewing direction IV in FIG. 1 with only one end cap, FIG. 5 shows a schematic diagram of a wiper blade with a receiving device, FIG

Recording device in perspective and Fig. 7, a and b, another embodiment of a receiving device. Description of the embodiments

A wiper blade 10 shown in FIG. 1 has a strip-like, elongated, spring-elastic support element 12 (FIGS. 1 and 2), on the lower, concave hinge side 31 facing the disc an elongated, rubber-elastic wiper strip 14

is attached longitudinal axis parallel. At the upper, facing away from the disc, convex hinge side 29 of the spring rail to be designated support member 12, the wiper blade-side part 15 of a connecting device 20 is arranged in its central portion, with the help of the wiper blade 10 articulated with a dash-dot line in Figure 1 indicated wiper arm 16 solvable can be connected. The wiper arm 16, which oscillates in the direction of a double arrow 18 in FIG. 1, is loaded in the direction of an arrow 24 to be wiped-for example, to the windshield of a motor vehicle-the surface of which is indicated by a dot-dash line 22 in FIG. Since the line 22 is intended to represent the strongest curvature of the disk surface, it is clearly evident that the curvature of the still-unloaded wiper blade resting against the disk at its two ends is greater than the maximum disk curvature (FIG. 1). Under the

Contact pressure (arrow 24) sets the wiper blade 10 with its wiper lip 26 over its entire length on the disk surface 22 at. This builds in mostly made of metal, resilient support member 12, a voltage which for a

proper conditioning of the wiper strip 14 and the wiper lip 26 over its entire length on the disk surface 22 and for a uniform distribution of the contact pressure (arrow 24) ensures.

In the following, the specific embodiment of the wiper blade according to the invention will now be discussed in greater detail.

In Fig. 2 it can be seen that the support member 12 of two, separated from each other

Spring strips 28 and 30 is constructed, which are spaced apart and justify a gap 32. The wiper blade-side part 15 of the connecting device 20 has in a lower region two U-shaped receptacles 34 and 36, in which the spring strips 28 and 30 are accommodated. The receptacles 34 and 36 comprise the spring strips 28 and 30 each over a larger part of its cross section, wherein the wiper arm 16

corresponding part of the connecting device 20 on the convex side 29 of the

Support member 12 is disposed, while the concave side 31 is opposite thereto. Furthermore, the attachment points 70 can be seen, which are arranged depending on the manufacturing method on the tape top and / or on the underside of the belt and depending on

Manufacturing method may have different sizes. Will the

Attachment points created by an externally applied adhesive, they may be limited in the case of a resin used closely to the input location, while a thin liquid adhesive by capillary action may be a slightly more extensive area affected. Even with ultrasonic welding, depending on the molten material, smaller or larger attachment points 70 can occur. Here size variations from 15 to 70 mm ^{2 are} easily accessible. It remains essential to the invention that the attachment point 70 is generated from one point and comprises a contiguous area.

In Fig. 3, the wiper blade-side part 15 of the connecting device 20 is shown schematically, wherein in the receptacle 34, the corresponding spring bar 28 is located, while the spring bar 30, not in the corresponding receptacle 36 is located. It can be seen that the receptacles 34 and 36, the spring strips 28 and 30 fit around. In the area above the spring strips 28 and 30 and above the gap 32, the wiper blade-side part 15 has a recess 40 into which, when the wiper blade 10

is assembled, a headboard of the wiper strip 14 comes to rest.

The wiper blade 10 shown in Fig. 4 below, without the wiper strip 14 or

Wiper lip 26 is drawn, shows the spring strips 28 and 30, the gap 32 and the receptacles 34 and 36 of the connecting device 20. It can be seen that in this embodiment of the wiper blade 10, the spring strips 28 and 30 are completely separated from each other and only by the connecting device 20 and end caps 38, of which in Fig. 4 is drawn only one at one end, are held together.

In Fig. 3 different openings and recesses for the coupling of the energy are shown, it being understood that the skilled person will select the respective embodiment for optimizing its connection and the process reliability accordingly. By coupling the energy in each case an attachment point 70 is generated. In the area 42, a simple through-hole 44 is shown, through which a sonotrode 45 can be placed directly on the spring strip and starting heating from the support element 20 can be established. In area 46, a blind hole 48 is shown, in which the sonotrode 45 first melts and displaces part of the material of the connecting device 20 before it comes into contact with the spring strip 28. In area 50, a two-stage through-hole is shown with a first larger blind hole 52 and In the area 56 a two-stage blind hole is shown, with a larger first blind hole 58 and an adjoining second smaller blind hole 60th

In Fig. 4, an off-center mounted through holes 44 can be seen from below, which are introduced into the receptacle 36. In the receptacle 34, a single through-hole 62 is alternatively inserted centrally analogous to the passage bore shown in the area 50. Of course, in a wiper blade, both spring rails will either have an attachment point either centrally or off-center, but not mixed.

In the schematic diagram of Fig. 5, a wiper blade according to the prior art is shown schematically. In the receiving device 20 is within the wiper blade side member 15 with its receptacle 34, the curved spring rail 32. It is fixed with two attachment points 70 on the wiper blade side part 15, wherein the two attachment points 70 have a distance 72 to each other, which is about 30 mm with real wiper blades , In the unloaded state, the spring rail 32 has a curvature that changes over its entire length and in today's systems has a minimum radius 74 in the region between the attachment points 70.

If such a wiper blade 10 is now placed on a windshield, the

Spring bar 32 in a more extended position along the double arrow 76 transferred. During each wiping cycle, the wiper blade 10 passes over areas of different curvature on the windshield, so that a constant movement along the double arrows 76 is produced. This periodic variation caused by the transfer of the curved spring bar 32 in a stretched form a periodic change in the distance 72, resulting in a periodic mechanical stress, in particular to shear stresses of the Fixing points 70 leads. The variation of the distance 72 may be in the range of 0.1 to 0.5 μηη. If the distance 72, for example, by incisions or undercuts within certain limits variable, the

Shearing stresses are absorbed by the system. With consistently rigid

wiper blade side part 15 loads the movement directly the attachment points 70th

In the wiper blade-side part 15 shown in FIG. 6, a blind hole 52 can be seen below which an attachment point 70 is indicated, which in the

assembled state, the connection between the wiper blade side member 15 and the spring rail 28 causes. In this central region, the wiper blade-side part 15 an axle 80 and an axle receptacle 82 in the form of a bore for various pendulum adapters. Depending on the adapter type, the axis 80 and / or the axle receptacle 82 is used. It is essential that the force introduced by the wiper arm, not shown, is transmitted along the part 24 via the axis 80 or axle receptacle 82 directly to the centrally introduced fastening point 70 and thus onto the spring strip 28. It creates a homogeneous flow of power.

In Fig. 7, a wiper blade side member 15 is shown in perspective and in the partial figure b from the top, in which the receptacle 32 relative to the receptacle 36 is extended in the partial figure a. Off-center in an area which, viewed from above, lies laterally next to the axis 80 or axle receptacle 82, blind bores 48 are introduced, of which either one per spring rail 28, 30 is used, to generate an attachment point 70 by means of ultrasound.

The variants of the wiper blade-side parts 15 according to FIGS. 6 and 7 differ with respect to the invention in that, in the vertical projection, the fastening point 70 in the region below the axis 80 or axle receptacle 82 in FIG

is arranged, while these, as seen in Fig. 7 a, are outside the range of the vertical projection. However, it can also be seen that, depending on the size of the attachment points 70, the areas in the vertical projection may overlap.

The force flow in the variant of the wiper blade-side portion 15 of FIG. 7 is carried out starting from the wiper arm along the arrow 24 via axis 80 and axle 82 to the eccentrically arranged attachment points 70 and from there to the spring strips 28, 30. This creates a slight torque in Direction of the arrow 84. This can

For example, be exploited to the traveling on the outer circle ends of the

Wischblatts 10 heavier load.

In the embodiments, the attachment point 70 is regularly designed as a melting point that is generated by ultrasonic action. However, it is also conceivable to produce the attachment point 70, for example by introducing adhesive or by a latching.

If the attachment point 70 is a melting point, it more or less intimately connects the material of the wiper blade-side part 15, which is preferably a thermoplastic plastic, directly with the spring rail 28, 30 or else with a coating of the spring rail 28, 30.

It is obviously not necessary always to use two spring rails 28, 30, it can also be used only a single spring rail, a so-called Monobeam.

It remains essential that only one attachment point 70 between the or

Spring rails 28, 30 and the wiper blade side part 15 is generated.

In the inventive method for producing the wiper blade, the

Spring rails 28, 30 introduced into the receptacles 34, 36 and mechanically fixed. Then is prepared per spring rail 28, 30 in attachment point, which connects the wiper blade-side part 15 of the connecting device with the spring rail 28, 30 of the support member 12.

The attachment points 70 are produced by means of ultrasonic welding, wherein the sonotrodes melt material of the wiper blade side part 15 and with the

Spring rails 28, 30 or their coating merge.

The fastening act for producing an attachment point 70 passes through several temporal stages. Different levels are controlled and / or changed in the stages. In particular, during one stage the flow of energy is controlled while in another stage the process path is controlled. In this case, "controlled" can be understood to mean a simple control or else a direct control in which parameters are continuously recorded and used to adapt the flow of energy or energy

Procedure of the sonotrodes 45 or the like.

In a preferred method, a sonotrode 45, after the spring bar 28, 30 is inserted into the wiper blade-side part 15, placed on the wiper blade-side part 15. Then, in a first stage, a limited amount of energy is supplied, in a second stage with the sonotrode 45 a defined way to process. The two stages are sequential in time, but may overlap to some extent.

Claims

claims

1. wiper blade for wiping of windows, in particular of motor vehicle windows, with a support element (12) for receiving a wiper strip (14) on which a

Connecting device (20) is attached, which has a wiper blade side part (15) with claw-like receptacles (34, 36) which engage around the support member (12) at least partially, wherein the support member one or more spring rails (28, 30), characterized in that the wiper blade-side part (15) of the connection device (20) is fastened to the support element (12) by means of one fastening point (70) per spring rail (28, 30).

2. wiper blade according to claim 1, characterized in that the one attachment point (70) per spring rail (28, 30) relative to the longitudinal extent of the wiper blade-side part (15) is arranged centrally.

3. Wiper blade according to claim 1 or 2, characterized in that the wiper blade-side part (15) has an axis (80) and / or an axle receptacle (82) and one

Attachment point (70) per spring rail (28, 30) in a vertical projection below the axis (80) and / or axle receiving (82) is arranged.

4. wiper blade according to claim 1, characterized in that the one attachment point (70) per spring rail (28, 30) relative to the longitudinal extent of the wiper blade-side part (15) is arranged eccentrically.

5. Wiper blade according to claim 1 or 4, characterized in that the wiper blade-side part (15) has an axis (80) and / or an axle receptacle (82) and one

Attachment point (70) per spring rail (28, 30) outside a vertical projection below the axis (80) and / or axle receiving (82) is arranged.

6. Wiper blade according to one of the preceding claims, characterized in that the one attachment point (70) per spring rail (28, 30) is a melting point.

7. wiper blade according to claim 6, characterized in that the one attachment point (70) per spring rail (28, 30), the material of the wiper blade side part (15) with the material of the spring rail (28, 30) or a coating of the spring rail (28, 30) connects.

8. A method for producing a wiper blade for wiping windows, in particular of motor vehicle windows, with a support element (12) for receiving a wiper strip (14) to which a connection device (20) is fixed, the wischblattseitiges part (15) with claw-like receptacles (34, 36), which the support element (12) at least

encompassing regions, wherein the support element has one or more spring rails (28, 30), in particular according to one of the preceding claims, characterized

in that the wiper blade-side part (15) of the connection device (20) is fastened to the support element (12) by means of one fastening point (70) per spring rail (28, 30).

9. The method according to claim 8, characterized in that the attachment point (70) is produced by means of ultrasonic welding.

10. The method according to any one of claims 8 to 9, characterized in that the attachment point (70) is generated in a plurality of temporal stages.

11. The method according to claim 10, characterized in that during one stage, the flow of energy and during another stage, the process path is controlled.