EP2678199A1

EP2678199A1 - Wiper blade for cleaning panes, in particular of motor vehicles

Info

Publication number: EP2678199A1
Application number: EP12705837.8A
Authority: EP
Inventors: Ruddy Crabbe
Original assignee: Robert Bosch GmbH
Current assignee: Robert Bosch GmbH
Priority date: 2011-02-24
Filing date: 2012-02-16
Publication date: 2014-01-01
Also published as: BR112013021409A2; CN103380030A; US20140075708A1; WO2012113715A1; DE102011004632A1

Abstract

The invention relates to a method for production and to a wiper blade for wiping panes, in particular motor vehicle panes, comprising a support element (12) for receiving a wiper strip (14), to which support element a connecting device (20) is attached, which has a wiper blade-side part (15) having receptacles (34, 36) surrounding the support element (12) at least in some regions. According to the invention, the inner width (42) of the receptacles (34, 36) essentially corresponds to, or is slightly larger than, the thickness of the support element (12).

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 under varying weather conditions. Especially in the case of the wiper blades produced in large numbers, a welded joint places high quality demands on the process management and thus makes the wiper blade more expensive, which should be avoided, especially with mass products.

Advantages of the invention The wiper blade according to the invention with the features of the main claim has the advantage that a welded joint can be avoided. It is replaced by a kind of clamping connection between the lugs of the wiper blade side of the

Connecting device and the support element. Because the clear width of the approaches in the

Substantially corresponds to the thickness of the support element or is only slightly larger is a positive and non-positive connection.

The features listed in the dependent claims are advantageous

Developments of the wiper blade according to the invention achieved. In particular, the difference between the clear width and the thickness of the support element in a

Tolerance band from 0 to 0.5 mm, preferably from 0 to 0.2 mm, but at least from 0 to 0.5 mm. The smaller the tolerance band is chosen the better will be the

Compounds between the wiper blade side member and the support member will also be mass produced for a plurality of wiper blades, but with the same cost.

Because the connecting device is pushed over the support element during production, it is advantageous if the clear width is just so great that the wiper blade-side part with its lugs can be pushed over the support element.

The connection between the wiper blade-side part and the support element is significantly improved by a heat treatment acting at least on the lugs. The heat treatment can achieve that the distance between the lugs in the region of the clearance and the support element is reduced and the adhesion increases. Particularly suitable for this purpose is the hot caulking, with the negative pressure heat is introduced directly into certain areas of the approaches. The introduced heat and applied pressure allow for deformation of the tabs and close possible gaps between the support member and the tabs. The positive and non-positive connection is thereby significantly improved.

It is advantageous if the support member has two spaced spring rails with one, preferably two end caps for covering the ends thereof. At least one

End caps may include a spacer for the spring rails. The single ones

Spring rails can be inexpensively manufactured and pre-bent to the necessary size to then be connected to the wiper blade side part of the connection device. By the spacer or the resulting force is reduced to the connection between the support member and connecting device. The connection devices can be provided in the region of the approaches with chamfers to facilitate the sliding of the connection device to the support element.

The inventive method for producing wiper blades allows a cost-effective production of mass produced wiper blades, because the

Connecting device because of the only slightly larger clearance of the

Wiper blade side part relative to the thickness of the support member can be easily pushed and positioned under the action of force on the support member.

In order to reduce the effort when pushing, the two spring rails can be applied without spacing together before pushing and be brought after pushing on distance.

The connection between the connection part and the support element can be significantly improved if after the positioning, in particular, the projections of the wiper blade side part are subjected to a heat treatment. This can preferably be done by heating, the individual parts of the approaches to each other warm caulking.

Preferably, the heat packs are pressed against each other in pairs, so the top and bottom of the approaches are pressed onto the rough and bottom of the support element. However, it is also conceivable to press heat loads on the outer longitudinal sides of the lugs, wherein at the same time a spacer is inserted between the spring rails, so the longitudinal sides of the spring rails are pressed into the lugs.

drawing

1 shows a wiper blade according to the invention in a perspective view with wiper arm indicated by dot-dash lines and a dash-dotted surface of a windshield, FIG. 2 shows a view according to II-II in FIG. 1, FIG. 3 shows a schematic representation of the view according to FIG. 2 with only one spring rail, Fig. 4 is a schematic view in the direction of view IV in Fig. 1 with only one end cap and Figures 5 and 6 embodiments with hot chewing jaws in the vertical and horizontal working direction. 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), to whose lower, belt-side hinge side 13 an elongated, rubber-elastic wiper strip 14 is fastened longitudinally parallel. At the upper, facing away from the disc hinge side 11 of the spring rail to be designated support member 12, the wiper blade-side part 15 of a connecting device is arranged in the central portion, with the help of the

Wiper blade 10 can be hingedly connected to a dash-dotted line in Fig. 1 indicated wiper arm 16. 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 the window 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 wiper blade still resting on the disk with its two ends is greater than the maximum disk curvature (FIG. 1). Under the contact pressure (arrow 24), the wiper blade 10 with its wiper lip 26 lays against the disk surface 22 over its entire length. This builds up in the made of metal, resilient support member 12, a voltage which for a proper investment of

Wiper strip 14 and the wiper lip 26 over the entire length of the disc surface 22 and for a uniform distribution of the contact pressure (arrow 24) provides.

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 rails 28 and 30 is constructed, which are spaced apart and justify a gap 32. The connecting device 15 has in a lower region two U-shaped receptacles 34 and 36, in which the spring rails 28 and 30 are accommodated. The receptacles 34 and 36 comprise the spring rails 28 and 30 each over a larger part of its cross section, wherein the wiper arm 16 corresponding to the part of the connecting device 15 is arranged on the convex side 29 of the support member 12, while the concave side 31 is opposite thereto. There is a small gap 41 between the spring rails 28, 30 and the respective receptacle 34, 36. In Fig. 3, the connecting device 15 is shown schematically, wherein in the receptacle 34, the corresponding spring rail 28 is located, while the spring rail 30, not in the corresponding receptacle 36, so that the inside width 42 can be seen. It can be seen that the receptacles 34 and 36, the spring rails 28 and 30 suitably embrace, with the existing tolerances will be discussed later. In the area above the spring rails 28 and 30 and above the gap 32, the connecting device 15 has a recess 40 into which, when the wiper blade 10 is assembled, a head part of a 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 rails 28 and 30, the gap 32 and the receptacles 34 and 36 of the connecting device 15. It can be seen that in this embodiment of the wiper blade 10, the spring rails 28 and 30 are completely separated from each other and only by the connecting device 15 or via end caps 38, of which in Fig. 4 only one is drawn at one end, are held together.

At least one of the end caps 38 has a spacer 39, which holds the spring rails 28, 30 at the distance of the gap 32 in the assembled state.

In the method according to the invention, the wiper blade-side part 15 of the

Connecting device 20 is pushed onto the support member 12, including the wiper blade side portion 15 in the receptacles 34, 36 has a clear width 42 which is equal to or slightly greater than the thickness of the spring rails 28, 30. For this purpose, the inside diameter is about 0 mm at least 0.05 mm greater than the thickness of the spring rails 28, 30. The assembly is easier if the allowable tolerance band is in the range of 0 mm to 0.2 mm. However, then there are increased demands on the heat treatment. A very simple assembly can be made if the tolerance band is between 0 mm to 0.5 mm, in which case it can be assumed that additional measures for reducing the gap 41 after the heat treatment become necessary. Especially with small gaps 41, the assembly of the wiper blade-side part 15 on the spring rails 28, 30 of the kind to perform that the spring rails 28, 30 are held by reducing the gap 32 side by side, the wiper blade side member 15 is pushed and only then

Spring rails 28, 30 placed on which distance of the gap 32 and thus in the

Shots are inserted. Of course, this method can also be advantageous for the other tolerances. In order to facilitate the insertion of the wiper blade-side part and spring rails 28, 30, the receptacles 34, 36 are in the region of the claw-like projections 50

Slant 51 on.

Once support member 12 and wiper blade side member 15 have taken the correct position to each other, is started with a heat treatment, which is directed either to the wiper blade side member 15 or on the support member 12 or on both elements. As a result, the clear width 42 of the type that it closes the gap 41 completely or at least largely changes.

In Figs. 5 and 6 it is shown how heat jaws 56 to 68 act on the wiper blade side part 15 and the spring rails 28, 30. In Fig. 5, the heat bricks 56, 58 are placed on each of an upper side of the receptacles 34, 36 and at the same time pressed against heat packs 60, 62 from below. The now flowing heat gives the material of the receptacles 34, 36 the ability to deform plastically, thereby reducing the clear width 42 and to close the gap 41 in whole or in part. The temperature of the

Heat jackets 56 to 62, the acting force and the elapsed time result from empirical values depending on the material and size of the receptacles 34, 36 and are optimized by small series of experiments.

In Fig. 5 is shown schematically that the heat packs may be profiled in order to act locally reinforced on the receptacles 34, 36 can. The thermal pads 60, 62 have narrow Ausstülbungen 72, with which they act on the lower edge region of the receptacles 34, 36 and press one or more notches. This increases the pressure and leads to an entertaining tile of the material. Depending on the surface condition of the spring rails 28, 30, this leads to a clawing or even sticking of the two joining partners.

As can be seen in FIG. 6, heat packs 64, 66 can also act on the outer longitudinal sides of the receptacles 34, 36 and thus dig the narrow sides of the spring rails 28, 30 into the receptacles 34, 36. To absorb the pressure on the spring rails 28, 30, another heat pack 68 is introduced into the gap 32 prior to hot caulking. These heat packs 68 preferably has a temperature that allows the

Spring rails 28,30 to heat so that they pass their heat to the receptacles 34, 36. Of course, the two methods shown in FIGS. 5 and 6 can be combined with one another, wherein the size of the heat packs 56 to 68 must be adapted accordingly.

In order to improve the adhesion between the material of the receptacles 34, 36 and the spring rails 28,30, a layer 70 in the region of the clear width 42 on or be applied to the spring rails 28, 30. This may be a flow behavior enhancing layer. However, it is also conceivable to improve the adhesion or a

Bonding enabling layer 70.

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 receptacles (34, 36) which engage around the support element (12) at least in regions, characterized in that the receptacles (34, 36) has a clear width (42). having the thickness of the support member (12) substantially equal to or slightly larger.

2. wiper blade according to claim 1, characterized in that the inside width (42) in a tolerance band of 0 mm to 0.5 mm, preferably from 0 mm to 0.2 mm, but at least from 0 mm to 0.05 mm greater than the thickness of the support element (12) is located.

3. Wiper blade according to one of the preceding claims, characterized in that the inside width (42) is just so large that the wiper blade-side part (15) with its receptacles (34, 36) on the support element (12) is pushed.

4. Wiper blade according to one of the preceding claims, characterized in that the attachment of the wiper blade-side part (15) to the support element (12) by at least on the receptacles (34, 36) acting heat treatment is improved.

5. Wiper blade according to one of the preceding claims, characterized in that the inside diameter (42) is reduced by hot caulking.

6. Wiper blade according to one of the preceding claims, characterized in that the support element (12) has two spaced spring rails (28, 30) whose ends are covered by one end cap (38), wherein at least one end cap has a spacer (39) ,

7. Wiper blade according to one of the preceding claims, characterized in that the connecting device (20) in the region of the receptacles (34, 36) run-on slopes (51).

8. A method for producing a wiper blade with a support element (12) and a connection device (20) which is fastened with a wiper blade side part (15) with lugs having a clear width on the support element (12), in particular according to one of the preceding claims , characterized in that the wisch blade-side member (15) with a only slightly larger clearance (42) than the thickness of the support member (12) is pushed and positioned under the action of force on the support member.

9. The method according to claim 8, characterized in that the support element (12) has two spaced spring rails, which are applied to each other before pushing the wiper blade side part (15) and are brought to the correct distance after positioning the wiper blade side part (15) ,

10. The method according to any one of claims 8 or 9, characterized in that the wiper blade-side part (15) is heat-treated after positioning.

11. The method according to any one of claims 8 to 10, characterized in that the wiper blade-side part (15) by means of heat pipes (56 to 68) are heat staked.

12. The method according to claim 11, characterized in that heat packs (56 to 68) are pressed in pairs against each other to heat and pressure on the top and bottom and / or on the long sides of the receptacles (34, 36) bring.