SE1650838A1

SE1650838A1 - Windshield wiper device

Info

Publication number: SE1650838A1
Application number: SE1650838A
Authority: SE
Inventors: Schmidt Klaus
Original assignee: Scania Cv Ab
Priority date: 2016-06-15
Filing date: 2016-06-15
Publication date: 2017-12-16
Also published as: WO2017217918A1; EP3472005A4; SE540687C2; EP3472005A1; CN109311454A; KR20190006555A

Abstract

The invention relates to a windshield wiper device (3), in particular for a motor vehicle (1), comprising a drive unit (29) which is coupled via a transmission device (31) to a wiper shaft (13), having a wiper arm (15) arranged to hold a wiper blade (17), the wiper shaft (13) being arranged so as to rotate about a rotation axis (19), wherein at least the wiper shaft (13) of the wiper device (3) is mounted pivotally about a pivoting axis (27), wherein the rotation axis (19) and the pivoting axis (27) are arranged at an angle to each other. The wiper device (3) further comprises a pivoting motor (21) arranged to pivot at least the wiper shaft (13) of the wiper device (3) about the pivoting axis (27). The invention also relates to a vehicle (1) and a method for wiping a windshield (5).

Description

WINDSHIELD WIPER DEVICE TECHNICAL FIELD The present invention relates to a windshield wiper device, a vehicle with such awiper device, and a method for wiping a windshield comprising a curvature.

BACKGROUND AND PRIOR ART The present invention relates to a windshield wiper device, a vehicle with such awiper device, and a method for wiping a windshield comprising a curvature accordingto the appended claims.

Vehicles, and in particular heavy goods vehicles, such as trucks and buses, areusually equipped with a windshield in the front regions of said vehicles. Thewindshield serves to protect the driver and passengers from weather conditions suchas rain and wind. As rain, or water from other sources, impair the visibility for thedriver, windshield wipers are commonly used to wipe the windshield by means of awiper blade swiping over the windshield. Windshield wiper devices and systems areknown in the art and typically comprise a drive unit coupled to a wiper shaft via atransmission device, wherein the transmission device rotates the wiper shaft backand forth by means of the power provided by the drive unit. The wiper shaft is furtherequipped with a wiper arm upon which a wiper blade suitable for the particularvehicle can be mounted.

Windshield wiper devices and systems may be designed in several ways dependingon the vehicle. Said wiper devices and systems may have one wiper arm and wiperblade swiping over the majority of the windshield, or a plurality of wiper arms andwiper blades, wherein each arm and blade covers separate portions of the windshield. Usually the speed of the movement of the wiper device may becontrolled by means of a control unit, which control unit typically has a user interfacewithin reach of the driver operating the vehicle.

Wiper devices and systems as described above are well designed to wipe anessentially flat surface with good results. However, as aerodynamics is of greatimportance for the wind resistance affecting the vehicle when driving, the shape ofthe windshield may not always be essentially flat in shape. To decrease windresistance and increase the aerodynamic behaviour of vehicles it is more and morecommon, for heavy goods vehicles in particular, to design the windshield with a sharper curvature, and/or having curved lateral edges to lower said wind resistance.

This however creates issues for wiping such windshields as the wiper devices andsystems cannot handle windshields with too sharp curves. ln such circumstances thewiper blades extends past the curvature in an essentially straight direction and thuscannot wipe said curved portion of the windshield.

This is an imperative problem as heavy goods vehicles are not, in some countries,authorized to de driven if large enough portions of the windshield in front of the drivercannot be wiped from water sufficiently.

The document EP 1939054 A2 discloses a windshield wiper device which attemptsto alleviate the above described problem. The wiper device according to thisdocument comprises a wiper shaft which is coupled to a drive unit via a transmissiondevice. The drive unit is further mechanically coupled to an actuator which shifts therotating axis for the wiper shaft by means of mechanically pivot the wiper devicewhen it is operated, wherein the rotation of the wiper shaft automatically pivot theaxis of rotation of the wiper shaft to shift the angle of attack of the wiper arm in relation to the windshield.

SUMMARY OF THE INVENTION Despite prior art there is a need to develop a windshield wiper device, which canwipe a windshield having a curvature. Also, there is a need to develop a wiper device, which can be used with high accuracy to guarantee good results to ensuresafety when driving a vehicle equipped with such a wiper device. Furthermore, thereis a need to develop a windshield wiper device which is customizable for windshieldshaving different designs with different shaped curvatures.

An object of the present invention is thus to provide a windshield wiper device, whichcan wipe windshield having a curvature with high accuracy. Another object of theinvention is to provide a wiper device which is customizable so as to be able to use for windshields having different designs with different shaped curvatures.

The herein mentioned objects are achieved by a windshield wiper device, a vehiclewith such a windshield wiper device, and a method for wiping a windshield, whichwindshield comprises at least one curved portion according to the independent claims.

According to an aspect of the invention the windshield wiper device, in particular fora motor vehicle, comprises a drive unit which is coupled via a transmission device toa wiper shaft, having a wiper arm arranged to hold a wiper blade. The wiper shaft isbeing arranged so as to rotate about a rotation axis, wherein at least the shaft of thewiper device is mounted pivotally about a pivoting axis. The rotating axis and thepivoting axis are arranged at an angle to each other. The wiper device furthercomprises a pivoting motor arranged to pivot at least the shaft of the wiper deviceabout the pivoting axis.

This has the advantage that the pivoting motor can pivot the wiper shaft in such away that the wiper arm and thus the wiper blade can be aligned with the curvature ofthe windshield. This further has the advantage that the pivoting motor can beadjusted for different curvatures or disabled if the wiper device is coupled to a windshield without a curvature present.

According to another aspect of the invention the pivoting motor is a servo motor.

This has the advantage that high accuracy is achieved for the pivoting movement ofthe wiper shaft.

According to yet another aspect of the invention the wiper device further comprises acontrol unit arranged to control the pivoting of at least the shaft provided by the pivoting motor.

This has the advantage that said pivoting is controlled in a very precise way bymeans of the control unit. This is advantageous as the control unit is adapted tocontrol the pivoting only and can therefore be designed for this object with high accuracy.

According to a further aspect of the invention the wiper device further comprises asensor, arranged to determine the position of the wiper arm and provide said positionto the control unit.

This has the advantage that the position of the wiper arm, and thus the wiper blade,always is available for the control unit, wherein the control unit therefore can controlthe pivoting of the wiper shaft in a very precise manner.

According to an even further aspect of the invention the sensor determines theposition of the wiper arm by means of determining a rotational position of the wipershaft.

This has the advantage that the sensor is easy to install into the wiper device andthat it can be securely attached to the wiper device where it is protected from outersources such as weather conditions. This further has the advantage that thewindshield is not obscured by the need of placing a sensor thereupon, or in the vicinity thereof.

According to an aspect of the invention the pivoting motor pivots the wiper shaft andthe transmission device when pivoting is performed.

This has the advantage that the transmission device is easier and less expensive tomanufacture as only the rotational movement of the wiper shaft needs to be providedby the transmission device.

According to another aspect of the invention the pivoting motor further pivots the drive unit when pivoting is performed.

This has the advantage that the wiper device is easy to manufacture as it can bedesigned and assembled as a whole without adding additional parts to achieve thepivoting of the wiper shaft within the wiper device. This is advantageous as thecoupling between the drive unit and the transmission device, and the couplingbetween the transmission device and the wiper shaft may be designed as awindshield wiper device without the pivoting aspect, but with the possibility to add thepivoting aspect to the wiper device with ease if desired.

According to yet another aspect of the invention a vehicle is provided, which vehicle comprises a windshield wiper device according to the present invention.

This has the advantage that a vehicle with a windshield wiper device which can wipea windshield having a curvature is provided.

According to a further aspect of the invention a method for wiping a windshield isprovided, which windshield comprises at least one curved portion, by using awindshield wiper device comprising a drive unit which is coupled via a transmissiondevice to a wiper shaft, having a wiper arm arranged to hold a wiper blade. Thewiper shaft is arranged so as to rotate about a rotation axis, wherein at least theshaft of the wiper device is mounted pivotally about a pivoting axis, wherein therotating axis and the pivoting axis are arranged at an angle to each other. Themethod comprising the steps of: a) rotating the wiper shaft by means of the drive unit and the transmission device soas to generate an angular movement of the wiper arm and the wiper blade, whereinsaid angular movement of the wiper blade wipes a portion of the windshield, which portion is defined by said angular movement; b) determining if the wiper blade is in the proximity of the at least one curved portionof the windshield; and c) adjusting the direction of the rotation axis of the wiper shaft by means of a pivotingmotor which pivots said rotation axis about the pivoting axis, wherein said pivoting aligns the wiper blade with a curvature of the curved portion of the windshield.

This has the advantage that a method is provided, which method can wipewindshield having a curvature. The pivoting motor can pivot the wiper shaft in such away that the wiper arm and thus the wiper blade can be aligned with the curvature ofthe windshield. This further has the advantage that the pivoting motor can beadjusted for different curvatures.

According to an even further aspect of the invention the wiper device of the methodfurther comprises a control unit, which is arranged for ca|cu|ating a position of thewiper blade during step a), which position is used by the control unit to perform stepb), wherein the control unit transmits an output signal to the pivoting motor so as to perform the adjustment of step c) based on the result of step b).

This has the advantage that the control unit can operate the pivoting motor in a veryprecise and controlled way. This further has the advantage that the control unit maybe adapted for windshields with different curvatures, thus making the methodcustomizable without having to mechanically re-design the windshield wiper device being used.

According to an aspect of the invention the wiper device of the method furthercomprises a sensor, which sensor is arranged to determine a rotational position ofthe wiper shaft, wherein the rotational position of the wiper shaft, in combination withdesign data for the wiper arm and the wiper blade, is used for ca|cu|ating the position of the wiper blade.

This has the advantage that the method can use a sensor which is easy to install intothe wiper device, and achieve a position of the wiper arm and blade with highaccuracy as the angular position of the wiper shaft is easy to determine with such a SGFISOI".

According to another aspect of the invention the control unit compares the position ofthe wiper blade to surface curvature data for the windshield to perform step b).

This has the advantage that the control unit at any given time will know if the wiperblade is located near a curvature present in the windshield. As the surface curvaturedata for the windshield tells the control unit where curvature is present the controlunit can easily be adapted to perform step b) knowing the position of the wiper blade.

According to yet another aspect of the invention a method for wiping a windshield isprovided, wherein the windshield comprises a first essentially flat portion, anintermediate curved portion and a second essentially flat portion, the first and secondessentially flat portions being at an angle to each other, wherein the methodcomprises the steps of: d) wiping the first essentially flat portion in a directiontowards the curved portion, by means of performing step a); e) wiping the curvedportion in a direction towards the second essentially flat portion, by means ofperforming step a), b) and c) simultaneously; and f) wiping the second essentially flatportion in a direction away from the curved portion, by means of performing step a)using the adjusted direction of the rotation axis of the wiper shaft of step e).

This has the advantage that the method may be used to wipe a type of windshieldwhich is suitable for heavy goods vehicles, wherein the windshield is adapted for lowwind resistance due to the added curvature. The method further has the advantagethat the method wipes both the windshield in front of, and on the side towards meeting traffic in relation to the driver driving said vehicle.

BRIEF DESCRIPTION OF THE DRAWINGS Below is a description of, as examples, preferred embodiments of the invention withreference to the enclosed drawings, in which: Figure 1 schematically illustrates a vehicle provided with a windshield wiper device according to the invention, Figure 2a schematically i||ustrates a perspective view of a windshield provided with awindshield wiper device according to the invention, Figure 2b schematically i||ustrates a top down sectional view of a windshield provided with a windshield wiper device according to the invention, Figure 3a schematically i||ustrates a schematically front view of a windshield wiperdevice with a wiper blade in a first position according to the invention, Figures 3b and 3c schematically illustrate front views of exemplary embodiments of awindshield wiper device with a wiper blade in a second position according to the invention, and Figures 4a and 4b show flowcharts of a method according to different embodiments for wiping a windshield according to the invention.

DETAILED DESCRIPTION OF PREFERRED EIVIBODIIVIENTS OF THE INVENTION Figure 1 schematically i||ustrates a vehicle 1 provided with a windshield wiper device3 according to the invention. The vehicle 1 comprises a windshield 5 whichcomprises a front portion 7 and a side portion 9. The windshield further comprises acurved portion 11, which curved portion 11 couples the front portion 7 and the sideportion 9 to each other. The windshield wiper device 3 comprises a wiper shaft 13, awiper arm 15 extending from the wiper shaft 13, and a wiper blade 17, detachablycoupled to the wiper arm 15. The front and the side portion 7, 9 of the windshield 5 ofthis example are essentially flat surfaces, which essentially flat surfaces areextending in two planes being essentially perpendicular to each other. The curvedportion 11 comprises a curvature which couples said two essentially perpendicularplanes to each other so as to provide a windshield 5 with a curved edge. Thus, thewindshield 5 is to be viewed as a one sheet of material covering the front portion 7,the side portion 9, and the intermediate curved portion 11 in relation to a driver and/or a passenger within the vehicle 1.

As is known in the art, windshields 5 are commonly provided with curvatures forbetter aerodynamic behaviour, wherein said curvatures may be oriented in variousdirections in relation to the area the windshield 5 is meant to cover. For curvatureshaving large radiuses, in the range of about 1500 mm to about 2000 mm and above,the design of the wiper arms 15 and wiper blades 17, being supported with springsand flexible joints, usually provides enough flexibility so as to wipe such curvatureswith good results. However, for a windshield 5 such as exemplified in figure 1 orsimilar, wherein the windshield 5 comprises a curved portion 11 provided to bridge afront portion 7 and a side portion 9, the radius of such a curvature is much smaller,typically going down in the region of a few hundred mm. As will be realized, theobject of the present invention is to be able to wipe such curvatures with radiusesbelow the range of about 1500 mm to about 2000 mm, which should be viewed assharp curvatures. The term curvature used in the patent application should thereforebe viewed as a curvature which cannot be wiped by means of a windshield wiperdevice 3 only relying of the flexibility of the wiper blade 17, and the typically springloaded mountings of such wiper blades 17.

Figure 2a schematically illustrates a perspective view of a windshield 5 provided witha windshield wiper device 3 according to the invention. The windshield 5 comprisesan essentially flat front portion 7, two curved edge portions 11, and two laterallyessentially flat side portions 9. The windshield wiper device 3 of this example isschematically illustrated and comprises a wiper shaft 13, arranged to rotate about arotation axis 19, a wiper arm 15 extending radially from the wiper shaft 13 andextending essentially parallel to the windshield 5. The windshield wiper device 3further comprises a wiper blade 17, detachably coupled to the wiper arm 15 andbeing arranged to wipe the windshield 5 in a back and forth swiping movement bymeans of an alternating clockwise and anti-clockwise rotation of the wiper shaft 13about the rotation axis 19. Said rotation is being provided by a drive unit andtransferred to the wiper shaft via a transmission device (the drive unit and thetransmission device are not shown in figure 2a). The windshield wiper device 3further comprises a pivoting motor 21 and a control unit 23. The control unit 23 is inthis example arranged in communication with the wiper shaft 13 wherein the controlunit 23 receives data for the rotational movement of the wiper shaft 13 by means of a sensor 25. The sensor 25 is in this example a sensor arranged on, or in the proximity of, the wiper shaft 13 wherein the sensor 25 can read the rotational displacement,the speed of said rotation and the direction of said rotation of the wiper shaft 13. Asthe wiper arm 15 holding the wiper blade 17 is attached on the wiper shaft 13, thecontrol unit 23 can thus calculate the position of the wiper blade 17. The control unit23 further comprises surface curvature data for the windshield 5 to which thewindshield wiper device 3 is mounted, wherein said data can be stored in the controlunit 23, on a separate memory or in a computer feeding the data to the control unit23. By means of a computer program P comprising computer code the control unit23 can then determine if the wiper blade 17 is in proximity of, and moving in adirection towards, a curvature of the windshield 5. When this occurs, the control unit23 operates the pivoting motor 21 to pivot the rotation axis 19 about a pivoting axis27 so as to align the wiper blade 17 with the present curvature of the windshield 5,wherein the contact between the wiper blade 17 and the windshield surface area ismaximized. As seen in figure 2a, the wiper blade is movable so as to wipe asegment of the essentially flat front portion 7, a segment of one of the curved edgeportions 11 and one of the laterally essentially flat side portions 9. This is performedby means of pivoting the wiper shaft 13 and thus the rotation axis 19 about thepivoting axis 27. Said pivoting is performed by means of the pivoting motor 21 whichis pivotally coupled to the windshield wiper device 3, or parts of said wiper device 3.The pivotal coupling may be arranged to pivot the wiper shaft 13, the wiper shaft 13and the transmission device, or the wiper shaft 13, the transmission device and thedrive unit (the transmission device and the drive unit are not shown in figure 2a). Thepivoting motor 21 may be a servo motor, but other types of motors known in the artmay also be used. By means of controlling the pivoting of the rotation axis 19, adevice is thus provided which can wipe windshields 5 of various designs comprisingvarious curvatures. Further, depending on the need and/or desire regarding how farthe wiper blade 17 needs to move in a rotational direction in relation to a driver in avehicle, the control unit 23 may be programmed to pivot the rotation axis 19 to acorresponding desired angle. lt is thus easy to modify the windshield wiper device 3according to the invention to different types of windshields 5 and vehicles, as thepivoting provided by the pivoting motor 21 can be adjusted to different predetermined angles, or even turned off if no curvature is present. 11 Figure 2b schematically i||ustrates a top down sectional view of a windshield 5provided with a windshield wiper device 3 according to the invention. The section ofthe windshield 5 can be viewed as part of the windshield 5 shown in figure 2a. Thisfigure further i||ustrates how the rotation of the wiper shaft 13 about the rotation axis19 and the pivoting of said rotation axis 19 about the pivoting axis 29 provides awiper device 3 which can wipe a curved portion 11 of a windshield 5 as well as theessentially flat front portion 7 in front of the driver, and an essentially flat side portion 9 on the side of the driver.

Figure 3a schematically i||ustrates a schematically front view of a windshield wiperdevice 3 with a wiper blade 17 in a first position P1 according to the invention. Thewindshield wiper device 3 comprises a drive unit 29 which is coupled via atransmission device 31 to a wiper shaft 13, having a wiper arm 15 arranged to hold awiper blade 17. The wiper shaft 13 is arranged so as to rotate about a rotation axis19, wherein at least the wiper shaft 13 of the wiper device 3 is mounted pivotallyabout a pivoting axis 27, wherein the rotating axis 19 and the pivoting axis 27 arearranged at an angle to each other. ln this example, said axles are arrangedessentially perpendicular to each other but other angles are also possible. Thewindshield wiper device 3 comprises first fastening means 33 arranged so as toattach the device to a vehicle, in particular a heavy goods vehicle comprising awindshield with at least one curved portion. The first fastening means 33 areprovided with bearing or similar to allow at least the wiper shaft 13 of the wiperdevice 3 to be pivoted about the pivoting axis 27. The wiper device 3 furthercomprises a pivoting motor 21 arranged to pivot at least the wiper shaft 13 of thewiper device 3 about said pivoting axis 27. The pivoting motor 21 may be a servomotor. The pivoting motor 21 is attached to the vehicle by means of secondfastening means 35. The pivoting motor 21 further comprises a pivoting shaft 37which pivots at least the wiper shaft 13 of the wiper device 3. Even further, thewindshield wiper device 3 comprises a control unit 23, which is arranged incommunication with the wiper shaft 13 and the pivoting motor 21, and a sensor 25,arranged to determine the position of the wiper arm 15 and provide said position tothe control unit 23. The sensor 25 in this example is a sensor 25 which determinesthe position of the wiper arm 15 by means of determining a rotational position of thewiper shaft 13, being arranged in proximity to the wiper shaft 13. The control unit 23 12 comprises a computer, or a link to a computer, comprising a computer program Pwith programme code for receiving the data containing the current position of thewiper arm 15 to calculate the position of the wiper blade 17 in relation to thewindshield of a vehicle. The control unit 23 further comprises stored data in amemory l\/l, or a link to readable data, containing the design parameters of thewindshield to control the pivoting of the rotation axis 19 when the wiper blade 17 is moved towards a curvature in the windshield.

As is illustrated in figure 3a, a rotation of the wiper shaft 13 rotates the wiper arm 15holding the wiper blade 17 about the rotation axis 19. This is illustrated by the wiperarm 15 and wiper blade 17 in a first position P1, and the wiper arm 15' and wiperblade 17' drawn with dotted lines being in an angled position Pa in relation to the firstposition P1. Said rotation is used to wipe essentially flat portions of a windshield of avehicle on which the windshield wiper device 3 is arranged.

Figures 3b and 3c schematically illustrate front views of exemplary embodiments of awindshield wiper device 3 with a wiper blade 17 in a second position P2 according to the invention.

Figure 3b schematically illustrates a front view of an exemplary embodiment of awindshield wiper device 3 with a wiper blade 17 in a second position P2 according tothe invention. ln this exemplary embodiment the pivoting motor 21 has pivoted thewiper shaft 13 and the transmission device 31 about the pivoting axis 27 to a positionwhich is perpendicular to the position of the wiper shaft 13 and transmission device31 seen in figure 3a. This in turn moves the rotation axis 19 of the wiper shaft 13 to adirection which extends in a direction perpendicular to the rotation axis 19 seen infigure 3a. Hence, a windshield wiper device 3 is provided which can wipewindshields having a curvature as the wiper blade 17 can be pivoted about a pivotingaxis 27, which pivoting aligns the wiper blade 17 with a curved portion of thewindshield as well as a side portion if present. This can be applied to wipewindshields with essentially flat portions coupled with an intermediate curved portion,wherein the windshield wiper device is mounted in such a way that the pivotingaligns the wiper blade 17 with said curvature. lt may also further be applied to wipewindshields having one essentially flat portion and one curved portion, wherein the 13 pivoting pivots the rotation axis 19 to align the wiper blade 17 with the curvatureduring the wiping procedure. The control unit 23 comprising a computer program Pwith program code can thus control the pivoting motor 21 so as to be adapted to anexisting curvature in a windshield to which the windshield wiper device 3 is mounted.The example seen in figure 3a pivots both the wiper shaft 13 and the transmissiondevice 31 which makes manufacturing of the wiper shaft 13 and the transmissiondevice 31 easy as the rotation of the wiper shaft 13 within the transmission device 31only needs to be designed for a rotationa| movement of the wiper shaft 13 within thetransmission device 31. That means mechanically simple bearings can be used forsaid rotation which provides a precise rotationa| movement with good results but stillbeing cost effective and easy to manufacture. The wiper shaft 13 can thus bemounted to the transmission device 31 by means of single axis rotationa| bearings,and the transmission device 31 can also be mounted to the drive unit 29 by means ofsingle axis rotationa| bearings. This allows for a simple design as bearings allowing for a three dimensional movements are not needed.

Figure 3c schematically illustrates a front view of an exemplary embodiment of awindshield wiper device 3 with a wiper blade 17 in a second position P2 according tothe invention. This exemplary embodiment is similar to that of figure 3b, but differs inthat the pivoting of the rotation axis 19 is performed by pivoting the wiper shaft 13,the transmission device 31 and the drive unit 29. This provides an embodiment of awindshield wiper device 3 which can be assembled as a whole without the pivotingfunction, but then add said pivoting function by means a hinged mounting of thewiper device 3 to a vehicle and the addition of a pivoting motor 21 rotationallycoupled to the windshield wiper device 3. This in turn leads to a very customizablewindshield wiper device 3 where the pivoting function may be optional at a laterstage of the assembly of said wiper device 3 to a specific vehicle. This ensures acost effective manufacturing process wherein windshield wiper devices 3 can bemanufactured for vehicles having essential flat windshields as well as windshield comprising curved portions in the same process line.

Figure 4a shows a flowchart of a method according to a first embodiment for wipinga windshield comprising a curvature according to the invention. The windshield wiperdevice 3 and the windshield 5 may according to this embodiment be viewed as 14 described in accordance with figure 2a. The method is performed by means of usinga windshield wiper device 3 comprising a drive unit 29 which is coupled via atransmission device 31 to a wiper shaft 13, having a wiper arm 15 arranged to hold awiper blade 17, the wiper shaft 13 being arranged so as to rotate about a rotationaxis 19, wherein at least the wiper shaft 13 of the wiper device 3 is mounted pivotallyabout a pivoting axis 27, wherein the rotating axis 19 and the pivoting axis 27 arearranged at an angle to each other. The method comprises the steps of a) rotatingthe wiper shaft 13 by means of the drive unit 29 and the transmission device 31 soas to generate an angu|ar movement of the wiper arm 15 holding the wiper blade 17,wherein said angu|ar movement wipes a portion of the windshield 5 with the wiperblade 17, which portion is defined by said angu|ar movement. Further, the methodcomprises the steps of b) determining if the wiper blade 17 is in the proximity or inthe area of a curved portion 11 of the windshield 5, and c) adjusting the direction ofthe rotation axis 19 of the wiper shaft 13 by means of a pivoting motor 21 whichpivots said rotation axis 19 about a pivoting axis 27, wherein said pivoting aligns thewiper blade 17 with a curvature of the curved portion 11 of the windshield 5. Steps a)and b) are simultaneously performed by means of a control unit 23 which operatesstep b) and c). Step a) is continuously performed by means of the drive unit 29 of thewiper device 3, wherein a sensor 25 provides the control 23 unit with data regardingthe position of the wiper blade 17 in relation to the surface area of the windshield 5underneath, and in proximity of the position of the wiper blade 17. By means ofdetermining the direction and speed of the wiper blade 17 during step a), andcomparing said variables with surface area design data of the windshield 5, thecontrol unit 23 can determine if a pivoting of the rotation axis 19 of the wiper device 3is needed by means of a computer program P and operate the pivoting motor 21accordingly. This means that step a) is continuously performed as long as the driveunit 29 provides power to the transmission device 31, and that step b)simultaneously is performed by means of the input data from step a) which is beingfed into the control unit 23. Based on the results of step b), the control unit 23performs step c) if a curvature is present in relation to the movement of the wiperblade 17.

This provided a method for wiping windshields 5 comprising curvatures wherein themethod can wipe several types of curvatures without the need to mechanically redesign the windshield wiper device 3. For example, if a windshield 5 consists of acurved portion 11 only, the steps a), b) and c) are all performed simultaneously so asto constantly adjust the rotation axis 19 of the wiper shaft 13 while the wiper blade 17is moved back and forth over said curved portion 11.

Figure 4b shows a flowchart of a method according to a second embodiment forwiping a windshield 5 comprising a first essentially flat portion 7 and a secondessentially flat portion 9, coupled with an intermediate curved portion 11. Thisembodiment may be as described in accordance with figure 2a and 2b, wherein thefirst essentially flat portion 7 may be a portion covering a front view for a driverdriving a vehicle, and the second essentially flat portion 9 may be a portion coveringa side view of a driver driving the vehicle, but other similar arrangements are alsopossible. ln the example described herein, the windshield wiper device 3 can bearranged to perform the method according to the invention by the steps of d), e) andf), wherein step d) comprises wiping the first essentially flat portion 7 in a directiontowards the curved portion 11, by means of performing step a). The step e) thencomprises wiping the curved portion 11 in a direction towards the second essentiallyflat portion 9, by means of performing step a), b) and c) simultaneously. Step f)further comprises wiping the second essentially flat portion 9 in a direction away fromthe curved portion 11, by means of performing step a) using the adjusted direction ofthe rotation axis 19 of the wiper shaft 13 of step e). Hence all three portions 7, 11, 9of the windshield 5 are wiped in a correct and precise manner by means of themethod of the invention.

Due to the pivoting of the rotation axis 19 being performed and adjusted by means ofa separate control unit 23, the wiper device 3 and the method according to theinvention may easily be adjusted to work on different types of windshields 5 and invarious different ways. Different modes of operation are easily obtainable bychanging mode and/or programing of the control unit 23. The wiper device 3 andmethod can for example be set to primarily wipe an essentially flat portion 7 of awindshield 5 and periodically wipe a curved portion 11 as well, or to wipe oneportion, being either essentially flat or curved, exclusively. The wiper device 3 andmethod may further also be set to wipe a plurality of essentially flat and curvedportions 7, 9, 11 together in one stroke of the wiper blade 17 by means of a 16 clockwise rotation and then wipe the same area of the windshield 5 in a single strokeby means of a following anti-clockwise rotation. Or as another example, the wiperdevice 3 and method may be set to first wipe one portion of the windshield 5 bymeans of the back and forth rotation of the wiper shaft 13, and then pivot the rotationaxis 27 to wipe a second portion of the windshield. Hence, a versatile wiper device 3and method for wiping windshields 5 are provided, wherein the wiper device 3 andmethod can be customized for several types of windshields 5 and different types ofneeds, the different types of need being based on, for example, different weather conditions.

As should be realized, the components and features specified above may within theframework of the invention be combined between the different embodiments specified.

Claims

17 CLAIIVIS

_ A windshield wiper device, in particular for a motor vehicle (1), comprising a drive unit (29) which is coupled via a transmission device (31) to a wiper shaft(13), having a wiper arm (15) arranged to hold a wiper blade (17), the wipershaft (13) being arranged so as to rotate about a rotation axis (19), wherein atleast the wiper shaft (13) of the wiper device (3) is mounted pivotally about apivoting axis (27), wherein the rotation axis (19) and the pivoting axis (27) arearranged at an angle to each other, characterized in that the wiper device (3) further comprises a pivoting motor (21) arranged to pivotat least the wiper shaft (13) of the wiper device (3) about the pivoting axis(27).
_ The wiper device according to claim 1, wherein the pivoting motor (21) is a SGFVO mOtOF.
_ The wiper device according to any of the preceding claims, wherein the wiper device (3) further comprises a control unit (23) arranged to control the pivotingof at least the wiper shaft (13) provided by the pivoting motor (21 )_
_ The wiper device according to claim 3, wherein the wiper device (3) further comprises a sensor (25), arranged to determine the position of the wiper arm(15) and provide said position to the control unit (23).
_ The wiper device according to claim 4, wherein the sensor (25) determines the position of the wiper arm (15) by means of determining a rotationalposition of the wiper shaft (13).
_ The wiper device according to any of the preceding claims, wherein the pivoting motor (21) pivots the wiper shaft (13) and the transmission device(31) when pivoting is performed. 18
7. The wiper device according to claim 6, wherein the pivoting motor (21) further pivots the drive unit (29) when pivoting is performed.
_ A vehicle (1 ), characterized in that the vehicle (1) comprises a windshield wiper device (3) according to any of the preceding claims.
_ A method for wiping a windshield (5), provided with at least one curved portion (11), by using a windshield wiper device (3) comprising a drive unit(29) which is coupled via a transmission device (31) to a wiper shaft (13),having a wiper arm (15) arranged to hold a wiper blade (17), the wiper shaft(13) being arranged so as to rotate about a rotation axis (19), wherein at leastthe wiper shaft (13) of the wiper device (3) is mounted pivotally about apivoting axis (27), wherein the rotating axis (19) and the pivoting axis (27) arearranged at an angle to each other, comprising the steps of: a) rotating the wiper shaft (13) by means of the drive unit (29) and thetransmission device (31) so as to generate an angular movement of the wiperarm (15) and the wiper blade (17), wherein said angular movement of thewiper blade (17) wipes a portion of the windshield (5), which portion is definedby said angular movement, characterized in that the method further comprises the steps of: b) determining if the wiper blade (17) is in the proximity of the at least onecurved portion (11) of the windshield (5); and c) adjusting the direction of the rotation axis (19) of the wiper shaft (13) bymeans of a pivoting motor (21) which pivots said rotation axis (19) about thepivoting axis (27), wherein said pivoting aligns the wiper blade (17) with acurvature of the curved portion (11) of the windshield (5).
10.The method according to claim 9, wherein the wiper device (3) further comprises a control unit (23), which is arranged for calculating a position ofthe wiper blade (17) during step a), which position is used by the control unit(23) to perform step b), wherein the control unit (23) transmits an output signalto the pivoting motor (21) so as to perform the adjustment of step c) based on the result of step b). 19
11.The method according to claim 10, wherein the wiper device (3) further comprises a sensor (25), which sensor (25) is arranged to determine arotational position of the wiper shaft (13), wherein the rotational position of thewiper shaft (13), in combination with design data for the wiper arm (15) andthe wiper blade (17), is used for calculating the position of the wiper blade(17).
12.The method according to any one of claims 10 and 11, wherein the control unit (23) compares the position of the wiper blade (17) to surface curvaturedata for the windshield (5) to perform step b).
13.The method according to any of claims 9 to 12, wherein the windshield (5) comprises a first essentially flat portion (7), an intermediate curved portion(11) and a second essentially flat portion (9), the first and second essentiallyflat portions (7, 9) being at an angle to each other, wherein the methodcomprises the steps of: d) wiping the first essentially flat portion (7) in a direction towards the curvedportion (11), by means of performing step a); e) wiping the curved portion (11) in a direction towards the second essentiallyflat portion (9), by means of performing step a), b) and c) simultaneously; andf) wiping the second essentially flat portion (9) in a direction away from thecurved portion (11), by means of performing step a) using the adjusteddirection of the rotation axis (19) of the wiper shaft (13) of step e).
14.A computer program (P), wherein said computer program (P) comprises programme code for causing a control unit (23) or a computer connected tothe control unit (23) to perform the steps according to any of the claims 9-13.
15.A computer programme product comprising a programme code stored on a computer-readable medium for performing the method steps according to anyof claims 9-13, when said computer programme (P) is run on a control unit (23) or a computer connected to the control unit (23).