KR100717517B1 - Wiper blade for windshields, especially automobile windshields, and method for the production thereof - Google Patents

Abstract

The present invention relates to a windshield wiper blade for a windshield, in particular a windshield of a motor vehicle, having at least one support element 12, a wiper strip 14, and a connecting device 16 for the wiper arm 18. The support element 12 is an elongated flat rod, to which the wiper strip 14 and the connecting device 16 are fixed. The supporting element 12, F, and _wf is the contact force was originally designed for the contact force or the wiper blade is applied on the wiper blade by the wiper arm (18), L is the length of the support element 12, E is the supporting element 12 of a modulus of elasticity, I _zz is when the moment of inertia of the cross-sectional profile of the periphery (perpendicular to the y-axis vertically while the s-axis and cooperating with the support element (12)) ^{_{z-axis, F wf * L 2/48}} * E * It is desirable to have a cross-sectional profile in a relationship where I _zz <0.009.

Support Element, Wiper Strip, Wiper Arm, Attachment, Wiper Blade

Description

Windshield wiper blade for automobile window and manufacturing method thereof {Wiper blade for windshields, especially automobile windshields, and method for the production}

In the case of a wiper blade in the manner described in the preamble of claim 1, the supporting element is a preliminary of the wiper blade pressing force, often referred to as pressing, against the windshield from the wiper arm throughout the wiping area wiped by the wiper blade. The set distribution must be guaranteed. By means of the corresponding curvature of the unloaded support element, i.e. when the wiper blade is not in contact with the windshield, the ends of the wiper strip which are completely in contact with the windshield during operation of the wiper blade, the curvature of the spherically curved automotive windshield Even if the radius changes with each position of the wiper blade, it is loaded against the window by the tensioned support element. That is, the curvature of the wiper blades should be slightly larger than the maximum curvature measured on the windshield to be wiped in the wiping area. The support element thus replaces an expensive support bracket structure with two spring rails disposed on the wiper strip as is used in conventional wiper blades (DE-OS 15 05 357).

The invention is based on a wiper blade according to the preamble of the independent claim. In the known wiper blade (DE-PS 12 47 161) a number of embodiments of the support elements are provided as a troubleshooting solution in order to ensure that the wiper blade exerts as uniform contact force as possible on flat glass windows over its entire length.

In the case of other known wiper blades in this manner (EP 0 528 643 B1), when the wiper blades are squeezed onto the flat windshield in order to obtain a uniform contact force of the wiper blades against spherically curved windows, The pressure load is much increased.

However, in both cases, it is desirable to distribute the pressure evenly over the entire wiper blade length of the wiper lip contained in the wiper blade and performing the original wiping operation when the wiper blade reverses its direction of operation. It causes a sudden flip from one drag position to another over its entire length. This drag state is essential for operating the wiping device effectively and silently. However, a sudden flip of such a wiper lip, which is inevitably associated with the lifting motion of the wiper blade, generates undesirable hitting noise. It is also a problem to match the tension of the support element to the different desired pressure distribution in each case in the spherically curved glass window.

EP 0 594 451 describes flat bar type wiper blades with various contours, said blades should not exceed certain side biases when applying test forces. For this purpose, through an extremely complex relationship of internal parameters that determine the elastic beam, one value is obtained which must not exceed a certain limit. From the equations presented, only difficult and incomplete conclusions can be drawn regarding the values to be used. Since the other data relate to unloaded wiper blades, no conclusion can be drawn on the performance of the wiper blades in operation.

It has also been found to be difficult to apply the known prior art, since the available parameters are not readily available for newly manufactured wiper blades.

Effects and advantages of the present invention are as follows.

The wiper blades according to the invention with the features of the independent claims have the advantage of very good wiping quality, since above all the vibration of the wiper blades on the windshield-the so-called slip-stick effect, is prevented. to be. This is due to the fact that in the slip stick effect, one must pay particular attention to the angle of the side bias and less attention to the absolute delay, i.e., the absolute bias of the tip under load. It is therefore desirable if the wiper blades are designed so that the side biases of the retarding ends of the wiper blades during operation do not exceed the angle of the side biases of a predetermined size. From the values for this angle found, important parameters for the wiper blade can be derived, which are in simple relationship with each other and should not exceed the upper limit of 0.009 in this relationship. This relationship and the upper limit results in a cross-sectional profile of a very simple support element, which results in good cleaning results. In particular, a wiper blade having a constant cross section over its entire length can be produced particularly simply by this method.

The measures described in the other claims enable the preferred improvement and implementation of the wiper blades according to the invention.

The wiping quality is further increased when the ratio of the product of the contact force and the square of the length to 48 times the elastic modulus of the support element and the product of the I _zz moment of inertia does not exceed the upper limit of 0.005.

Particularly well-used cross-sectional profiles are rectangular in shape and have a substantially constant width and a substantially constant thickness over the length of the wiper blades. And the support element may be composed of individual bars which are arranged side by side or in turn up and down and whose total widths or total thicknesses are combined into one full width and / or full thickness. In the case of such a rectangular cross-sectional profile may be written to the moment of inertia (I _zz) is d * b ^3/12, d and b in the formula are each entire thickness and the entire width. When the upper limit specified by this method does not exceed 0.009, in particular 0.005, a very simple relation can be obtained that allows the support element for the wiper blade to be optimized.

The side bias angle γ during operation of the wiper blade is 0.5 °, in particular 0.3, even when a particularly cross-sectional profile of a complex support element is selected, which may vary depending on the length of the wiper blade or may have a ladder-like structure, for example. Good wiping quality can be obtained if considered not to exceed °. This designation holds when the mean coefficient of friction μ is 1 and can be enlarged or reduced correspondingly for friction values greater or less than that.

The side bias angle γ refers to the angle at which the tangent to the end of the support element extends in the axis of the support element extending in the direction of the longitudinal width of the support element. In a first approximation, the angle may be an angle formed by an axis in the longitudinal extension direction of the support element and a straight line passing through the point of action of the wiper arm with respect to the support element and the end of the support element.

Very good wiping results can be obtained if the width b and the thickness d to the entire length of the support element are within a constant ratio range. In particular, the product of the square of the width and thickness should not exceed 40 times the square of length and less than 20 times the square of length. The widths and / or thicknesses of the assembled support element are combined to form one full width or full thickness each, which is then considered.

The wiper blade according to the invention having the features of claim 10 has the advantage that only one parameter needs to be changed in order to adjust the decreasing contact force distribution towards the outside. The curvature or curvature course along the support element can be pre-adjusted in a bending machine that can be programmed freely. As a result, a short series of tests to optimize the contact force distribution and hence the curvature course can be performed quickly and inexpensively. It is particularly desirable if the coordinates governing the course of curvature extend along the inertial element. Thus there is no need for an inversion to the costly Cartesian coordinate system that requires the shifting of subsequent "x values" each time a change is made at one position x.

If the elastic modulus of the support element material and the surface moment of inertia of the support element are constant over its length, the mathematical relationship between the second derivative of the curvature along the appropriate coordinates and the contact force progression along the appropriate coordinates is particularly simple. In a predetermined contact force distribution, the curvature can be calculated directly by two integrations or numerically.

If the curvature of the glass window is subtracted from the curvature of the support element, and the second derivative of the curvature of the glass window is subtracted from the second derivative of the curvature of the support element, it is possible to optimally adjust the wiper blade as described above for a glass window having a complicated curvature course. In this case the contact force distribution can be given in advance as desired for a wiper blade pressed against a flat windowpane. The difference of the second derivative of each curvature is then proportional to the contact force distribution.

The wiper blade according to the invention with the features of claim 15 is characterized in that excellent wiping results can be obtained without special adjustment to the average window type. The very simple measures described above allow the contact force distribution to meet the requirements in the general case. The fulcrum, which determines the curvature course to be maintained, is sufficiently accurate.

The wiper blade according to claim 15 is optimized by the action of claim 16. Even in the case of complicated windshield curvature, the cleaning quality can be improved by presetting the contact force distribution at a specific support point. Nevertheless, the wiper blades can be designed without complicated calculations. The curvature course can generally be predetermined and can be optimized by simple tests. Excellent cleaning quality is ensured only in the precondition that the contact force distribution given when the wiper blade is pressed against the windshield to be wiped is higher at the end of the wiper blade in approximately half the area between the center and the end of the wiper blade.

In the method according to the present invention for producing such a wiper blade, each parameter is selected according to the idea of the present invention, and the support element is bent in advance so that its curvature satisfies at least one of the above conditions. It is particularly preferable to bend the support element in advance and then assemble it with the wiper strip and the connecting element. However, it is only possible to join the connecting element with the supporting element and then attach the wiper strip.

1 is a perspective view of a wiper arm abutting a windshield and connected with a wiper arm loaded against the windshield;

FIG. 2 is a side elevational view of a wiper blade placed over a window without load, shown in a reduced scale relative to FIG.

3 is an enlarged cross-sectional view of the wiper blade taken along line III-III of FIG.

4 and 5 are modified views of FIG.

6 and 7 show wiper blades of another embodiment described in a coordinate system.

8 and 9 are graphs of calculations and measurements for contact force distribution over the length of a wiper blade, respectively.

10 is a non-scaled basic side view of the support element belonging to the wiper blade.

The wiper blade 10 shown in FIG. 1 has a support element 12 for the wiper strip 14, also referred to as an elongated spring elastic flat bar, which is shown separately in FIG. 10. have. As can be seen from FIGS. 1, 3 and 4, the support element 12 and the wiper strip 14 are connected to one another in parallel in the longitudinal axis. On the upper side of the support element 12, which is opposite to the windshield 15 to be wiped-shown in FIG. 1-is arranged a connecting device 16 as a connecting means, by which the wiper blade 10 is arranged. It may be detachably connected to the drive wiper arm 18 guided by the vehicle body. On the lower side of the support element 12 facing the window 15, a rubber elastic wiper strip 14 is elongated.

The free end 20 of the wiper arm 18 is provided with a hook which serves as a corresponding connection device, which surrounds the pivot bolt 22 belonging to the connection device 16 of the wiper blade 10. The fastening between the wiper arm 18 and the wiper blade 10 is made by fastening means formed of a known adapter, which is not shown in detail.

The wiper arm 18 and its hook end 20 are loaded against the windshield 15 to be wiped in the direction of the arrow 24, and the surface to be wiped is the dashed line 26 in FIGS. 1 and 2. Is shown. The contact force F _wf , arrow 24, contacts the wiper blade 10 to the surface 26 of the windshield 15 to be wiped over its entire length.

Since the dashed-dotted line 26 shown in FIG. 2 should represent the maximum curvature of the windshield surface in the wiping area, the curvatures at both ends of the wiper blade 10 that are not yet loaded in contact with the windshield are spherically curved. It can be clearly seen that it is larger than the maximum curvature of Under the contact force F _wf (arrow 24) the wiper blade 10 is in contact with the windshield surface 26 over its entire length by its wiper lip 28 belonging to the wiper strip 14. Tensile forces are formed within the band-shaped spring resilient support element 12, which allows the wiper strip 14 or wiper lip 28 to contact the automotive windshield 15 uniformly over its entire length. During wiper operation, the wiper arm 18 operates the wiper blade 10 over the windshield 15 transversely to its length. This wiping or working operation is shown by double arrows 29 in FIG. 1.

In the following, specific embodiments of the wiper blade according to the present invention will be described in detail. As shown non-scaled in FIG. 3, the wiper strip 14 is disposed on the lower band face of the support element 12, facing the window 15. The wiper strip 14 is spaced apart from the support element 12 and narrowed from both longitudinal sides thereof to maintain the tilting hinge 30 extending over the entire length of the wiper blade 14. The tilting hinge 30 is transformed into a wiper lip 28 having a substantially wedge shaped cross section. By the contact force (arrow 24) the wiper blade or wiper lip 28 is pressed against the surface 26 of the windshield 15 to be wiped, the wiper lip being influenced by the wiping action-FIG. In particular only one of the two opposite wiping direction (double arrow 29) motions is shown and shown by the direction arrow 32-tilted to the so-called dragging position, in which the wiper lip 28 extends over the entire length thereof. It is supported by the part of the wiper strip 14 fixed to 12). The support, indicated by arrow 34 in FIG. 3, is always done at the upper edge located behind the wiper lip 28 in each wiping direction, depending on the respective wiping direction (double arrows 29 or 32), thus This support is always done above the window in the so-called dragging position. This drag position is necessary for the wiper device to operate effectively and silently. The reversal of the drag position is performed at the so-called reversal position of the wiper blade when the wiper blade 10 reverses its wiping operation (double arrow 29). The wiper blade performs the lifting operation due to the tilting of the wiper lip 28. The raising operation is performed in the opposite direction to the arrow 24 and thus in the opposite direction to the contact force. In another wiping operation in the opposite direction of the arrow 32, the mirror image of FIG. 3 is thus obtained.

In FIG. 4, which is shown enlarged relative to the wiper blade of FIG. 1, a cross-sectional profile 40 with a rectangular cross section of width b and thickness d is shown. In addition, a coordinate system is shown above the support element 12. 6, the s coordinate which conforms to the curvature of the support element 12 is described as a 3rd coordinate, The y coordinate and z coordinate are perpendicular | vertical to this s coordinate.

Now when the wiper blade 10 is pressed against the windshield 26 by the force F _wf (arrow 24), in particular by the wiper arm 18, a constant force distribution p (s) appears and the distribution of the force is supported. The moment (M (s)) at the center of the element 12 is generated. Constant contact force distribution desirable for wiper operation

In this case, the moment is

Becomes and thus

Becomes

In the case of an outwardly decreasing contact force distribution, especially suitable for tilting the wiper lips, the moment (M (s)) over the entire length of the lip is slightly smaller than the moment calculated for the constant force distribution:

Now assuming that the coefficient of friction μ for dry windows is about 1, the side moments in operation are equal to the bending moment M (s), which is obtained in particular from the preset contact force distribution p (s).

The side bias angle γ is obtained from the side bending moment, which is calculated by integrating the individual biases from the operating point of the wiper arm to the wiper blade to the end of the wiper blade. When the connecting device 16 is arranged centrally, the angle of convenience is calculated as follows:

Taking into account the relationship of moments to constant contact force distributions, we obtain the following simple estimate of the angle γ:

By integration we get

The present invention is based in particular on the fact that good wiping quality can be obtained, especially by the prevention of vibration, when the angle γ does not exceed a size of 0.5 ° (= 0.009 rad), in particular a size of 0.3 ° (= 0.005 rad). I put it. Thus a simple relationship can be derived between the contact force and the geometric size of the wiper blade,

In particular, it is <0.005.

For the most frequent rectangular profile 40, as shown in FIG. 3, the moment of inertia is as follows:

Where

d = thickness of the support element,

b = width of the support element.

therefore,

In particular, the width b and the thickness d are selected so that <0.005.

If the support element 12 is divided into two separate elastic bars 42 and 44 as shown in FIG. 4, the width b is the width of the individual widths b1 and b2 when the above first approximation is taken into account. The sum can be taken. B = b1 + b2. Thus, for such other systems, a simple relationship between the width and the thickness of the support element can be derived.

If the rectangular cross-sectional profile is not selected, it is necessary to determine the moment of inertia I _zz and use it appropriately in the above relation. In addition, the above considerations should be taken into account in which the cross section changes over the entire length of the wiper blade or the point of action off the center of the wiper arm in the wiper blade.

The support element 12, which serves to distribute the contact force (arrow 24) in order to allow the wiper lip 28 to switch as little as possible from its one drag position to the other drag position, is a wiper for the windshield surface 26. The contact force of the strip 24 or wiper lip 28 is designed to be greater at its central portion 36 (FIG. 10) than at at least one of the two end portions 38.

The distribution of the pressing force over the support element depends on several parameters of the support element, such as, for example, the cross sectional profile, the transverse cross section over the length of the support element or the radial elongation (R (s)) along the support element. The optimization of the support element towards a given contact force distribution p (s) is thus very complicated. The present invention now provides that for a support element having a constant, particularly rectangular cross-section, over the length of the support element, the contact force distribution p (s) has a curvature K (s) along a coordinate s extending along the support element. Based on the fact that can be determined by presetting)). The curvature K (s) is equal to the inverse of the radius as a function of s:

In the support element, there is a relation between the bending moment M, the radius of the support element R, its elastic modulus E, and the surface moment of inertia I prevailing at each position. This relation is particularly simple with respect to the coordinate (s) associated with the support element:

By two derivatives of position (s) we obtain the following relation:

Since the second derivative of the bending moment M according to the coordinates s interlocking is the same as the contact force distribution p according to the coordinates s generated when the support element is pressed against a flat window, the coordinates s interlocking The second derivative of the curvature K (s) is determined to be consistent with the contact force distribution p on the flat window, except for the constant. The constant depends on the modulus of elasticity (E) and the surface moment of inertia (I), which moments are obtained very simply when in a rectangular cross section. In addition, in the case of a preset contact force distribution p which decreases as it goes outwards, the profile of the curvature K can be obtained either by calculation or by a simple test. The external shape of the support element and the parameters necessary for its manufacture can thus be obtained simply by one skilled in the art.

In order to take into account the shape of the windshield in which the wiper blade is to be used, the relation must be corrected on the basis of the contact force distribution p according to the coordinate s, which coordinates are preset for the flat windshield and are directed outwards. And then divided by the modulus of elasticity (E) and the surface moment of inertia (I). The second derivative of the curvature of the window (K _Scheibe (s)) according to the coordinate (s) should be added to it:

This makes it simple for a person skilled in the art to construct a support element for a particular window as follows:

The experience points determine the length (L) and the cross-sectional profile, in particular the width (b) and thickness (d),

The contact force (F _wf ) or the contact force distribution (p) on the flat glass window, which ensures a good wiping quality, is likewise determined by empirical value,

_Measuring the curvature of the window (K _Scheibe (s)),

_{Differentiating} the curvature K _Scheibe (s) of the window twice according to the coordinate s associated with the curvature,

Calculating the second derivative of the curvature K (s) of the support element according to the above relation,

By two integrations, the curvature (K (s)) of the support element is obtained.

When the wiper blade is pressed against a flat window, the curvature K along the interlocking coordinates s is made such that the dominant contact force distribution is greater at the end of the wiper blade in the region approximately half way between the center and the end of the wiper blade. When present, it has been found that good wiping results can be obtained. 8 and 9 show this area for one side. The present invention is based on the fact that the progress of the contact force distribution p of the region 40 is less important than the relationship of the contact force in the region 40 to the contact force distribution p at the end of the wiper blade. 8 and 9 show the total length of the wiper blade, respectively, and the wiper blade end has a value of 0.5L since the connecting device 16 is arranged in the center of the wiper blade.

The coordinate s along the curvature K along the length of the support element 12 is such that the contact force distribution p given when the wiper blade is pressed against the flat window to be wiped is approximately half way between the center and the end of the wiper blade. Very good wiping results are obtained with a larger value at the end of the wiper blade in the region of. By taking into account the progress of the windshield provided with the wiper blades, the general suitability for any windshield is limited and the selected windshield is optimally wiped.

FIG. 10 shows the possible curvature K of the support element 12, which can generate a contact force distribution p of the wiper lip 28 of the windshield 15, decreasing towards the wiper blade end. In the case of the spring resilient support element 12 which is unloaded and has more void curvature with respect to the windshield than is curved in the wiping region wiped by the wiper blade, the curvature K is the support element 12. It is formed so that the curvature is larger in the center part 36 than the end part 38 of the ().

By reducing the contact force of the wiper lip to the windshield surface 26 at one or both ends of the wiper blade, sudden flips or snaps are prevented when the wiper lip 28 changes from one drag position to another. Rather, in the case of the wiper blade according to the invention, the wiper lip can be gently tilted from the wiper blade end to the center of the wiper lip or to the other wiper lip end. FIG. 3, in connection with FIG. 1, shows that even in the case of a spherically curved glass window, the end portion of the lightly loaded wiper lip 28 is still effectively in contact with the glass window surface.

All embodiments are common in that the pressing force (arrow 24) on the windshield 15 of the wiper strip 14 is greater than in at least one of its end portions 38 at least in its central portion 36. . This is the same even when the support element is composed of several parts, unlike in the case of the specifically shown wiper blade 10 with the integrated support element 12 shown as a spring rail. However, depending on the situation, it may be necessary to preset other contact force distributions. However, wiper blades may also be envisioned that achieve excellent wiping results by the relationships shown.

In the method according to the invention for producing a wiper blade, the contour and curvature K are first determined as already described above, and then the support element 12 is assembled with the wiper strip 14 and the connecting device 16. In the case of a support element consisting of two parallel flat bars, the bars are preferably pre-bent with each other, ie directly in succession, which ensures a very symmetrical and thus torsionally stable structure of the wiper blades. Both halves of the support element are further machined together to avoid accidental separation in a continuous process. After bending the support element, it is first installed by means of a coupling element, for example by installing the wiper strip, for example by gluing or vulcanizing, or by inserting the support element halves in the longitudinal groove of the wiper strip, in particular in the case of two support element halves. In particular, when welding the coupling element, the wiper strip is installed after sufficient time so as not to damage the wiper rubber.

Claims (18)

At least one support element 12, a wiper strip 14, and a connecting device 16 for the wiper arm 18, the support element 12 being an elongated flat bar, the bar having the wiper In the windshield wiper blade, in which the strip 14 and the connecting device 16 are fixed, The support element 12 has a cross-sectional profile according to the following formula,

_Wherein F _wf is the contact force exerted on the wiper blade by the wiper arm 18 or the contact force originally designed for the wiper blade, L is the length of the support element 12, and E is the support element 12 And I _zz is the moment of inertia of the cross-sectional profile around the z axis perpendicular to the y axis and perpendicular to the s axis interlocking with the support element (12). The method of claim 1,

Wiper blades, characterized in that. The wiper blade according to claim 1 or 2, characterized in that the support element (12) has a cross-sectional profile (40) which is rectangular with a constant width (b) and a constant thickness (d). 3. The support element (12) according to claim 1 or 2, wherein the support element (12) consists of at least two individual bars (42, 44) and the widths (b1, b2) of the individual bars (42, 44) add up to give a total width ( b) to be a wiper blade. The width b and the thickness d of the support element 12 according to claim 1 or 2,

The wiper blades, characterized in that selected to be. The width b and the thickness d of the support element 12 according to claim 1 or 2,

The wiper blades, characterized in that selected to be. delete At least one support element 12, a wiper strip 14, and a connecting device 16 for the wiper arm 18, the support element 12 being a long elongated flat bar, the bar having the wiper strip In the windshield wiper blade for an automobile window to which the 14 and the connecting device 16 are fixed, The support element is given by L in meters and b and d in millimeters, A wiper blade having a length L, a width b, and a thickness d so that a relationship of 20L ² <bd ² <40L ² is established. 9. The wiper blade according to claim 8, wherein said support element comprises at least two elastic bars whose widths add up. At least one elongated support element 12, a wiper strip 14, and a connecting device 16 for the wiper arm 18 for pressing the wiper blade 10 against the windshield 15 in an operating position. The support element 12 is a long flat, the bar is fixed to the wiper strip 14 and the connecting device 16 and the bar is unloaded by the wiper arm 18 In the windscreen wiper blade having a curvature of The curvature along the coordinate s along the length of the support element 12 is such that when the second derivative of the curvature according to the coordinate s is pressed against the flat window 15, the wiper blade 10 is pressed. And a value proportional to the contact force distribution (P (s)) occurring, and wherein the contact force distribution decreases toward at least one end. The method of claim 10,

Where s = coordinates along the support element K (s) = curvature of the support element M (s) = bending moment E = modulus of elasticity I = surface moment of inertia of the support element about the neutral axis p (s) = specific load per unit length = contact force distribution Wiper blades, characterized in that the formula. At least one elongated support element 12, a wiper strip 14, and a connecting device 16 for the wiper arm 18 for pressing the wiper blade 10 against the windshield 15 in an operating position. The support element 12 is elongated, and the bar is fixed to the wiper strip 14 and the connecting device 16 and the bar is unloaded by the wiper arm 18. In the windshield wiper blade having a curvature, The curvature along the coordinate s according to the length of the support element 12 is the difference between the second derivative of the curvature according to the coordinate s and the second derivative of the curvature of the glass window 15 from the center region 40 to the end. A wiper blade, characterized in that it has a value that decreases as it is directed. 13. The wiper blade according to claim 12, wherein the central region (40) is a mounting position of the connecting device (16). The formula according to claim 12 or 13, wherein

Where s = coordinates along the support element K (s) = curvature of the support element M (s) = bending moment E = modulus of elasticity I = surface moment of inertia of the support element about the neutral axis p (s) = specific load per unit length = contact force distribution K _Scheibe (s) = curvature of the window Wiper blades, characterized in that. At least one elongated support element 12, a wiper strip 14, and a connecting device 16 for the wiper arm 18 for pressing the wiper blade 10 against the windshield 15 in an operating position. The support element 12 is a long flat, the bar is fixed to the wiper strip 14 and the connecting device 16 and the bar is unloaded by the wiper arm 18 For a windshield wiper blade having a curvature at The curvature along the coordinate s along the length of the support element 12 is such that the contact force distribution P (s) given when the wiper blade 10 is pressed against the flat window 15 is the wiper blade 10. Wiper blade having a greater value at the end of the wiper blade (10) in an area (40) approximately half way between the center and the end of the blade. At least one elongated support element 12, a wiper strip 14, and a connecting device 16 for the wiper arm 18 for pressing the wiper blade 10 against the windshield 15 in an operating position. The support element 12 is a long flat, the bar is fixed to the wiper strip 14 and the connecting device 16 and the bar is unloaded by the wiper arm 18 For a windshield wiper blade having a curvature at The curvature along the coordinate s along the length of the support element 12 is such that the contact force distribution p (s) given when the wiper blade 10 is pressed against the windshield 15 to be wiped is the wiper A wiper blade, characterized in that it has a larger value at the end of the wiper blade in the region (40) approximately halfway between the center and the end of the blade (10). delete In the manufacturing method of the wiper blade, Determining a cross-sectional profile comprising the length (L) and width (b) and thickness (d) required for the window to be wiped, Determining a contact force (F _wf ) or a contact force distribution (p) for the flat window, which ensures good wiping quality, _Measuring the curvature of the window (K _Scheibe (s)), _{Differentiating} the curvature K _Scheibe (s) of the window twice according to a coordinate s associated with the curvature, A calculation step of obtaining a second derivative of the curvature K (s) of the support element according to the following relational expression,

here, s = coordinates along the support element K (s) = curvature of the support element E = modulus of elasticity I = surface moment of inertia of the support element about the neutral axis p (s) = specific load per unit length = contact force distribution K _Scheibe (s) = curvature of the window Obtaining the curvature K (s) of the support element by two integrations; Bending the support element according to the obtained curvature K (s); A method of manufacturing a wiper blade comprising the step of coupling a support element, a wiper blade and a connecting device.

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