WINDSCREEN WIPER DEVICE FOR LARGE CURVED WINDSCREENS

Abstract

A windshield wiper device for large size curved windshields comprising first and second arms hingedly connected to each other at a distal end by a main spacer and reciprocatingly operable. The device further comprises a windshield wiper blade rockingly mounted relative to said main spacer through rocking means and a secondary spacer mounted on the distal end in redundancy with said main spacer. The rocking means comprise a first toothed member integral with said secondary spacer and a second toothed member integral with said wiper blade, which are mounted meshed with one another to cause the rocking of said wiper blade about time longitudinal axis thereof in the rocking direction opposite to the direction of reciprocating movement of said first and second arms.

Claims

1. A windshield wiper device for large size curved windshields comprising: first and second arms hingedly connected to each other at a distal end by a main spacer, said first and second arms being reciprocatingly operable at a proximal end and a windshield wiper blade rockingly mounted about a longitudinal axis relative to said main spacer through rocking means characterized in that it further comprises a secondary spacer mounted on said distal end and which works redundantly with said main spacer, in that said rocking means comprise: a first toothed member integral with said secondary spacer and a second toothed member integral with said wiper blade, and in that said first and second toothed members are mounted meshed with one another to cause the rocking of said wiper blade about said longitudinal axis in the rocking direction opposite to the direction of reciprocating movement of said first and second arms.

2. A windshield wiper device of claim 1, characterized in that it further comprises a support member, said second toothed member being fixedly mounted in said support member and said wiper blade being rockingly mounted on said support member about an axis transversal to the longitudinal direction of said wiper blade.

3. A windshield wiper device according to claim 1, characterized in that said first toothed member a straight rack and said second toothed member is a toothed circular segment.

4. A windshield wiper device according to claim 1, characterized in that it comprises longitudinal walls adjacent both sides of said first or second toothed members, said longitudinal walls having a height such that in the engaged state of said first and second toothed members it is at least the same as the height of the teeth of said first and second toothed members.

5. A windshield wiper device according to claim 4, characterized in that said first or second toothed members include said longitudinal walls forming an integral part.

6. A windshield wiper device according to claim 1, characterized in that said secondary spacer is farther removed from said proximal end than said main spacer.

7. A windshield wiper device according to claim 1, characterized in that it comprises a windshield wiper liquid spray member integral with said wiper blade and which comprises at least one windshield wiper liquid outlet, arranged to apply said windshield wiper liquid ahead of said wiper blade, in the direction of forward movement of said wiper blade.

8. A windshield wiper device according to claim 7, characterized in that said spray member is mounted in the direction transversal to the longitudinal direction of said wiper blade.

9. A windshield wiper device according to claim 7, characterized in that said windshield wiper liquid outlet is oriented such that in an operative position said windshield wiper liquid is applied substantially in the longitudinal direction of said wiper blade and in the opposite direction to the force of gravity.

10. A windshield wiper device according to claim 8, characterized in that it comprises two windshield wiper liquid outlets on opposite sides of said spray member and a lower outlet oriented towards said windshield, such that windshield wiper liquid is applied along the entire length of said wiper blade.

11. A windshield wiper device according to claim 9, characterized in that said spray member comprises at least two windshield wiper liquid outlets arranged on both sides of said wiper blade, alternately operable to apply windshield wiper liquid ahead of said wiper blade in the direction of forward movement of said wiper blade.

Description

BRIEF DESCRIPTION OF THE DRAWINGS

[0030] Further advantages and features of the invention will become apparent from the following description, in which, without any limiting character, preferred embodiments of the invention are disclosed, with reference to the accompanying drawings in which:

[0031] FIG. 1 is a schematic exploded perspective view of the windshield wiper device of the invention.

[0032] FIG. 2 is an enlarged perspective view of the first toothed member of the windshield wiper device of FIG. 1.

[0033] FIG. 3 is an enlarged perspective view of the second toothed member of the windshield wiper device of FIG. 1.

[0034] FIG. 4 is a front perspective detail view of the distal portion of the windshield wiper device of FIG. 1.

[0035] FIG. 5 is a rear perspective detail view of the distal portion of the windshield wiper device of FIG. 1.

[0036] FIGS. 6A and 6B are schematic views from above of the windshield wiper device in a central position and in an end position, respectively.

[0037] FIGS. 7A and 7B are schematic front views of the windshield wiper device of FIGS. 6A and 6B in a central position and in an end position, respectively.

[0038] FIGS. 8A and 8B are kinematic diagrams seen from above of the windshield wiper device in a central position and in an end position, respectively.

[0039] FIGS. 9A and 9B are front kinematic diagrams of the windshield wiper device in a central position and in an end position, respectively.

DETAILED DESCRIPTION OF EMBODIMENTS OF THE INVENTION

[0040] FIG. 1 shows the windshield wiper device 1 for large size curved windshields according to the invention.

[0041] The pantograph type device 1 comprises first and second arms 2, 4 made in the form of metallic rods defining two links of the kinematic chain. Both arms are hingedly connected together at the distal end 8 through the main spacer 10 by way of main pins 38 and main bearings 40. This main spacer 10 forms the link closing the kinematic chain of the four bar mechanism of the device 1. The main spacer 10 is made from a folded sheet with two assembly tabs 52 on which the longitudinal axis 48, around which the wiper blade 12 can rock to compensate the attack angle, may be mounted.

[0042] At the proximal end 6, namely the end opposite to the distal end 8, the first and second arms 2, 4 are fixedly mounted on first and drive shafts 32, 34. The first shaft 32 is the shaft of an assembly having a motor 28 and gear train 30. The second shaft 34 is attached to the first shaft 32 by means of a bar linkage mechanism 36. Through the motor 28, the gear train 30 and the bar mechanism 36, both shafts drive the first and second arms 2, 4 synchronously in a reciprocating movement.

[0043] At the distal end 8 and preferably at a position further removed from the proximal end 6 than the main spacer 10, the device 1 is provided with a secondary spacer 22. This is provided in extensions 60 projecting from the joints of the main spacer 10 in the first and second arms 2, 4. The secondary spacer 22 is also hinged relative to the arms by the secondary pins 42 and the secondary bearings 44.

[0044] Alternatively, the secondary spacer 22 may be closer to the proximal end 6 than the main spacer 10, but this configuration is less advantageous, since it complicates the assembly and accessibility of the assembly. This secondary spacer 22 is formed by a C-shaped sheet.

[0045] The secondary spacer 22 works redundantly with the main spacer 10 and the purpose thereof is to cause the rocking movement of the wiper blade 12 by way of the rocking means 14. This is to be seen in detail in FIGS. 6A to 9B and will be explained hereinafter.

[0046] The rocking means 14 are formed by first and second toothed members 16, 18 engaging one another. The first toothed member 16 is a straight rack which is fixedly mounted to the secondary spacer 22 through the screws 58. In turn, the second toothed member 18 is a toothed sector fixedly mounted to the wiper blade 12 for the rocking movement thereof to compensate the attack angle. Alternatively, the first toothed member 16 could be, for example, a crown gear.

[0047] As is to be seen in the figures, the wiper blade 12 is mounted in holes provided in the tabs of the U-shaped support member 46 by bolts 50, being able to rock around an axis transverse to the longitudinal direction thereof.

[0048] In order to achieve the rocking movement of the wiper blade 12 relative to the first and second arms 2, 4 for compensating the attack angle, the support member 46 holding the wiper blade 12 is rockingly mounted on the tabs 52 of the main spacer 10 through the axis 48.

[0049] Since it is fixedly mounted on the secondary spacer 22, the first toothed member 16 converts the reciprocating movement of the arms of the device 1 into a rocking movement, plus a slight movement of translation of the second toothed member 18, which is to be seen in FIGS. 6A to 9B. Thus, starting out from the central position of FIGS. 6A and 7A, when the arms are driven to the right of the figures, the secondary spacer 22 moves relative to the position of the axis 48 and this causes a rotational torque on the support member 46 which causes the rocking of the support member 46 and the wiper blade 12 about the axis 48 which is to be seen in FIGS. 6B and 7B. It is to be seen in them how the rocking occurs in the opposite direction to the reciprocating movement of the first and second arms 2, 4.

[0050] There is a quantifiable relationship between the stroke angle of the first and second arms 2, 4 and the leaning angle assumed by the support member 46 and, consequently, the attack angle of the wiper blade 12.

[0051] To this end, for a greater understanding of the mechanism, there is given with reference to FIGS. 1 and 8A to 9B a kinematic scheme where the different links (7 in all) are identified. The number of joints or kinematic pairs (9 in all) are identified with small letters, a, b, c, d, e, f, g, h, i, being distributed according to the following classes. [0052] Rotary or lower pairs: a, b, c, d, e (*) f (*) h, i (8 in all, Class I, two redundant ones being indicated with the sign (*)). [0053] Rolling and sliding or upper pairs: g (1 in all, Class V).

[0054] The mobility m of the device 1 according to Grublers formula is:

m=3(n1)2j.sub.1j.sub.2

where n is the number of links, j.sub.1 is the number of lower kinematic pairs (each one constrains two degrees of freedom on the plane) and j.sub.2 the number of upper kinematic pairs (each one constrains one degree of freedom on the plane). Therefore, applied to the device 1:

m=3(71)2(61)=1810=8

[0055] It is a mechanism of grade 8 (positive).

[0056] To determine the relationship between the wipe angle of the arm and the attack angle the following formula is available:

=arctan (DIR sin ()

[0057] Note that the attack angle and, consequently, the distance x can vary, by modifying the distance of the engagement R such than when R is increased, the attack angle is reduced or vice versa.

[0058] The lip 56 forms the wiping rubber profile which is located on the windshield surface. Thus, depending on the angular positions adopted by the support member 46, the lip 56 is positioned according to the desirable attack angle.

[0059] A further object of the invention is that the device should be as robust as possible and should allow operations in environments with demanding conditions such as dust, mud, branches or other agents highly prejudicial for the life of the device 1. To this end, in this case, the first toothed member 16, namely the rack, is provided with longitudinal walls 20 adjacent the teeth which are to be seen in detail in FIG. 2. Preferably, the longitudinal walls are arranged adjacent the rack forming an integral part. Nevertheless, these walls could be independent members. As is to be seen in this figure, these longitudinal walls 20 have such a height that in the engaged state of the first and second toothed members 16, 18 it is at least the same as the height of the corresponding teeth. It is also to be seen in this embodiment that the height of the longitudinal walls 20 is greater at the head of the teeth, whereby the engagement zone is perfectly protected against the entry of items such as branches or the rest and also greatly hinders the penetration of dust or mud.

[0060] It is to be seen in FIGS. 4 and 5 that to improve the cleaning of the device 1, there is provided a spray member 24 for windshield wiper liquid integral with the wiper blade 12. The spray member 24 is arranged transversely to the longitudinal direction of the wiper blade 12. On the other hand, in the preferred embodiment of FIGS. 4 and 5, the spray member 24 is provided with six windshield wiper liquid outlets 26, arranged to apply windshield wiper liquid ahead of said wiper blade 12, in the forward moving direction thereof. Thanks to this configuration, the spray member 24 rocks with the wiper blade 12 during the modification of the attack angle in a fixed position. Consequently, the jets ejected by the spray member 24 are always applied in a constant position relative to the wiper blade 12 and therefore the efficiency of cleaning is maintained constant for any attack angle assumed by the wiper blade in its entire windshield wiping stroke.

[0061] In order to optimize the washing capacity of the spray member, four of the windshield wiper liquid outlets 26 are oriented to apply the liquid in the longitudinal direction of the wiper blade 12. Thus, the two outlets 26 of FIG. 4 eject the jet of windshield wiper liquid in the opposite direction to the force of gravity, such that the jet in the operative and assembled position of the device 1 is always ejected at least upwards. In turn, the two rear outlets 26, to be seen in FIG. 5, eject the jet towards the proximal end 6. On the other hand, the spray member 24 is also provided with lower outlets 26 ejecting the jet in a direction substantially perpendicular to the windshield. In any case, for reasons of efficiency, it is preferred that in the embodiments having a single outlet 26 the windshield wiper liquid is always ejected in the direction opposite to the force of gravity to take maximum advantage of the liquid.

[0062] In this case, in spite of it not being essential for the invention, the spray member comprises windshield wiper liquid outlets 26 which can apply liquid to both sides of the wiper blade 12. Thus, windshield wiper liquid is applied along the entire length of the wiper blade 12.

[0063] The embodiments described this far represent non-limiting examples, such that the man of the art will understand that beyond the examples shown, multiple combinations among the claimed features are possible within the scope of the invention.