EP1984651A1

EP1984651A1 - Rotation control mechanism especially for a window wiping device pertaining to a motor vehicle

Info

Publication number: EP1984651A1
Application number: EP07704431A
Authority: EP
Inventors: Marcel Trebouet; Franck Cathala
Original assignee: Valeo Systemes dEssuyage SAS
Current assignee: Valeo Systemes dEssuyage SAS
Priority date: 2006-02-13
Filing date: 2007-02-07
Publication date: 2008-10-29
Also published as: JP2009526696A; US20090025173A1; WO2007093545A1; FR2897408A1; FR2897408B1

Abstract

The invention relates to a rotation control mechanism (1) characterised in that the control mechanism (1) comprises: a primary shaft (10) that can be driven in an alternating axially rotating manner; a drive carrier fixed to the primary shaft (10); a secondary shaft (30) which is mounted in an axially rotatable manner in relation to the drive carrier; a fixed cam (40) provided with a specific profiled element (41); and a control element (50) which is fixed to the secondary shaft (30) and can co-operate in a sliding manner with the cam profiled element (41) during the displacement of the drive carrier (20) in relation to the fixed cam (40). The invention is also characterised in that the sliding of the control element (50) along the cam profiled element (41) can control the axial pivoting of the secondary shaft (30).

Description

ROTATION CONTROL MECHANISM, IN PARTICULAR FOR A VEHICLE WIPING DEVICE

AUTOMOBILE

The present invention relates to a mechanism which is intended, on the one hand, to drive a secondary shaft rotating alternately around a primary shaft, and secondly, to control the axial pivoting on itself of said shaft secondary.

The invention finds an interesting application, but not exclusive, in the field of wiper systems for windshields of motor vehicles.

[0003] Today, car manufacturers want to equip vehicles with windshields with complex or panoramic surfaces, the particularity of which is to have side portions with strong curvatures.

In order to obtain optimum wiping quality on such complex surfaces, it is known to use windscreen wiper systems using wiping brushes with variable angles of attack. With this type of device indeed, the inclination of the wiper relative to the normal to the surface of the windshield, changes according to the angular position of the associated wiper arm. This characteristic makes it possible to comply with the recommendations of angle of attack, and this throughout the scan cycle.

The wiper devices of the state of the art, which have this feature, generally comprise a brush holder arm which is mounted to pivot axially, and which is controlled on the move by means of operating control means. the primary scanning motion of the system.

Such control means may in particular be in the form of a wiper which is integral with the wiper arm and which is able to cooperate by sliding with a fixed cam whose profile extends in three dimensions. from space.

This type of arrangement, however, has the disadvantage of being particularly bulky, especially in height, by precisely the three-dimensional shape of the cam. Its use is moreover limited to relatively progressive corrections, which proves to be somewhat inadequate in the case of a windscreen with complex or panoramic surface which requires rather rapid variations of the angle of attack when the broom wiping reaches one of the side edges with strong curvatures.

To remedy these difficulties, it has been developed control means implementing a planar cam much less voluminous, in association with a mechanism converting the linear motion conventionally generated by said cam into a rotary motion transmittable to the swing arm arm.

However, this type of embodiment still has significant disadvantages which are essentially related to its great structural complexity. The motion conversion mechanism requires the implementation and cooperation of a very large number of parts.

A first consequence is that such a system is ultimately extremely expensive, because of the cumulative value of the intrinsic cost of different parts, but also because of the additional cost of assembly that their presence in large numbers implies .

Another disadvantage of this second embodiment lies in the fact that the control means also present too much space, even if it is manifested here above all in the direction of the length. The motion conversion mechanism must indeed be implanted along the axis of the brush arm.

A final disadvantage inherent in the very large number of parts and therefore links involved, is the inevitable existence of geometric dispersions problems that are likely to cause malfunctions, see even irreversible damage.

Also, the technical problem to be solved by the object of the present invention is to provide a rotation control mechanism that would avoid the problems of the state of the art being notably significantly less expensive to manufacture. , while offering a small footprint.

The solution to the technical problem posed consists, according to the present invention, in that the rotation control mechanism comprises:

a primary shaft capable of being driven in alternating axial rotation,

a drive support secured to the primary shaft,

a secondary shaft mounted for axial rotation with respect to the drive support,

a fixed cam with a specific profile,

a control member secured to the secondary shaft and able to slide-cooperate with the cam profile during the displacement of the drive support with respect to the fixed cam, and in that the sliding of the control member along the cam profile is suitable for Lemmander the axial pivoting of the secondary shaft.

It should be noted that throughout this text, the term profile very generally refers to the active surface of the cam, whether it is for example its outer periphery or an inner contour delimiting a through groove.

Anyway, the invention as defined thus has the advantage of having a relatively simple structure compared to the rotation control mechanisms of the state of the art.

The cam of the invention is not conventionally used to transform a rotational movement into a linear movement, knowing that this linear movement must then be compulsorily converted into a rotary motion to be transmitted to the swing arm arm. The cam of the invention is indeed used to generate a pivoting of the control member, which will then directly cause the axial rotation of the brush holder arm.

This is a much simpler operating principle than those of the prior art, which implies that its implementation requires considerably fewer parts. This results in a significant gain in terms of manufacturing cost, whether at the level of the intrinsic cost of each constituent element of the mechanism, or that of assembly.

The combination of a planar cam and a directly adjacent control member further allows to limit the dimensions of the rotational control mechanism. The latter can thus offer an optimal compactness to promote its integration, for example in a windshield wiper device for a motor vehicle.

The present invention also relates to the features that will emerge during the following description, which should be considered in isolation or in all their possible technical combinations.

This description, given by way of non-limiting example, is intended to better understand what the invention is and how it can be achieved. It is furthermore given with reference to the accompanying drawings, in which: FIG. 1 is a perspective view from above and in transparency, which partly illustrates a wiper device incorporating a rotation control mechanism according to a first embodiment of FIG. realization of the invention. Figure 2 is a top view which shows the wiper device of Figure 1 in a position called fixed stop.

Figure 3 is a view similar to Figure 2, but with the wiper in a so-called opposite fixed stop position. Figure 4 is a perspective view from above showing the relative disposition of the main components of the rotational control mechanism.

Figure 5 shows the rotation control mechanism in section along a plane passing through both the axis of the secondary shaft and the axis of the control member.

Figure 6 is a perspective view from above which illustrates a variation of the first embodiment of the invention.

Figure 7 is a view similar to Figure 6, but in perspective from below.

Figure 8 is a bottom and side perspective view showing a rotational control mechanism according to a second embodiment of the invention.

Figure 9 is a view similar to Figure 8, but more frankly in perspective from below.

For the sake of clarity, the same elements have been designated by identical references. Likewise, only the essential elements for understanding the invention have been represented, and this without regard to the scale and in a schematic manner.

Figures 1 to 5 illustrate a wiper device which is intended to equip a panoramic windshield of a motor vehicle, and which incorporates a rotational control mechanism 1 according to a first embodiment of the invention.

It should be noted that these different representations are only partial, in that all the components of the wiper device are not systematically represented for obvious reasons of clarity. This is particularly the case of the motor means, the wiper arm and the wiper blade.

Anyway, and in accordance with the object of the present invention, the rotational control mechanism 1 is first provided with a primary shaft 10 which is intended to be driven in alternating axial rotation. For this, the primary shaft 10 is also coupled to motor means which are in this case classically constituted by an electric gear motor.

The rotational control mechanism 1 is then provided with a drive support 20 which is integral with the primary shaft 10. In this particular embodiment, chosen solely by way of example, the drive carrier 20 is concretely in the form of a housing 21 which is composed of a body 22 and a cover 23. The body 22 is in fact fitted on a tronoonic portion 11 of the primary shaft 10, where it is held by through a locking nut 12 which is screwed to the end 13 of said primary shaft 10.

The rotating control mechanism 1 also carries a secondary shaft 30 which is mounted to rotate axially with respect to the drive support 20. In this embodiment, this secondary shaft 30 is positioned so that substantially perpendicular to the primary axis 10. Its mobility in rotation is further guided by two rings 32, 33 which are integrated in the body 22 of the housing 21. Finally, the secondary shaft 30 is directly integral with a head rotary 31 which is responsible for supporting the wiper arm of the wiper device, mounted articulated.

The rotational control mechanism 1 further comprises a fixed cam 40 having a specific profile 41 which is a function of the effective curvature of the windshield surface to be treated. Limmobilisation of the cam 40, relative to the rest of the control mechanism 1, is effected by means of a fixing lug 47 which is intended to be rigidly secured to the motor vehicle. Note that this attachment can operate directly by coming to anchor on the body, or indirectly by coming attached to the motor means for example.

The rotational control mechanism 1 finally has a control member 50 which is integral with the secondary shaft 30, and which is able to cooperate by sliding with the profile 41 of the fixed cam 40, during the relative displacement between the drive support 20 and said fixed cam 40. In this embodiment, the control member 50 is positioned substantially perpendicular to the axis of the secondary shaft 30. This means that in the end it extends substantially coplanar with the axis of the primary shaft 10, regardless of the pivot angle of the secondary shaft 30.

Anyway, the assembly is also arranged so that the sliding of the control member 50, along the profile 41 of the fixed cam 40, is able to control the axial pivoting of the secondary shaft 30.

It should be noted that in theory, the control member 50 can take any form and / or structure that can enable it to fulfill its simple function of control arm.

In this embodiment, however, and according to a feature of the invention, the control member 50 preferably comprises a lever 60, one end 61 is secured to the secondary shaft 30, a free mounted contact member 70 in axial rotation on the lever 60, as well as elastic return means 80 able to maintain the contact element 70 bearing against the profile 41 of the fixed cam 40.

According to another feature of the invention implemented in this embodiment, the contact element 70 is further mounted slidably movable along the lever 60. This feature is primarily intended to ensure contact between the contact element 70 and the cam profile 41, regardless of the angular value of the pivoting of the secondary shaft 30. Depending on the nature of the control member 50 used, this mobility may be essential for the proper functioning of the mechanism, or to be purely incidental with a simple objective of optimization. In the case of the embodiment object of Figures 1 to 5, its presence is mandatory.

Indeed, according to a first embodiment of the invention, the contact element 70 which is intended to cooperate by sliding with the cam profile 41 is constituted by a substantially spherical ball 71. Furthermore, the profile corresponding cam 41 is in the form of a through groove 42 which is formed in the thickness of the fixed cam 40.

In a particularly interesting way, the cross section of the through groove 42 is substantially complementary to that of the corresponding portion of the ball 71. This means in other words that the inner edge of the fixed cam 41, which defines the groove through 42, has walls that are substantially concave.

According to a complementary feature of this first embodiment, the elastic return means 80 are able to drive the ball 71 moving along the lever 60 to a position of contact with the profile 41 of the fixed cam 40 .

In this exemplary embodiment, the elastic return means 80 are concretely constituted by a compression spring 81, one end of which bears against a stop 62 formed at the distal portion of the lever 60, and whose other end exerts a pushing force on the sliding ball 71, via an anti-friction washer 82 (Figure 5).

The sliding assembly of the ball 71, combined with the action of the compression spring 81, makes it possible to compensate for the variations in geometry that appear at the mobile connection connecting the secondary shaft 30 and the cam 40, when the implementation of the rotation control mechanism 1.

The distance between the attachment point of the lever 60 on the secondary shaft 30 on the one hand, and the contact point of the control member 50 on the cam profile 41 on the other hand, is indeed not constant. It evolves progressively with the rotation of the drive support 20, since the cam profile 41 does not extend concentrically with respect to the axis of the primary shaft 10. [0040] However, the sliding mobility of the ball 71 makes it possible to vary the length of the lever arm of the control member 50. It is thus possible to automatically adapt this length according to the actual existing gap. between the point of attachment on the secondary shaft 30 and the contact point on the cam profile 41. The role of the compression spring 81 is absolutely complementary, since it consists in ensuring, just as automatically, an effective contact between the ball 71 and the cam profile 41 when the length of the lever arm of the control member 50 is changing.

In this particular embodiment, it is observed that the cam 40 has in fact a composite structure. It consists in fact of a support piece 43 which incorporates an insert 44 supporting the profile 41. This configuration makes it possible to optimize the choice of materials according to the effective role of each part of the cam 40.

But of course, and perfectly equivalent, it is quite possible to use a fixed cam 40 in the form of a single piece in which the profile 41 is directly formed.

Figures 2 and 3 are used to better visualize the kinematics of the rotary control mechanism 1 as previously described.

It can be seen in FIG. 2 that when the wiper device is in the fixed stop position, the rotary head 31 is disposed in a plane which does not have a particular inclination with respect to the axis of the primary shaft 10.

By cons, and in accordance with Figure 3, it is noted that the rotary head 31 has tilted axially about 25 ° when the wiper arrives in the opposite fixed stop position, that is to say that the drive support 20 has rotated a little more than 90 °.

Between these two extreme positions of fixed stop and opposite fixed stop, the pivoting of the rotary head 31 will not vary linearly, but it will follow a specific law dictated by the cam profile 41. Thus, in this example, the rotation of the head 31 will only begin around 75 ° rotation of the drive carrier 20, then continue with acceleration and deceleration phases adapted to the curvature of the associated windshield.

Figures 6 and 7 illustrate a variant of the first embodiment of Figures 1 to 5, which is distinguished mainly by the particular nature of its resilient biasing means 80. It is indeed a spring sheet 83 which is used here to maintain the contact element 70 bearing against the profile 41 of the fixed cam 40.

In practice, this plate spring 83 is secured along the groove 42, on the face of the cam 40 which is not oriented in opposition to the secondary shaft 30. It thus extends substantially symmetrically with respect to the insert 44, and its section is substantially complementary to that of the portion of the ball 71, which n is not introduced into the cam profile 41.

The fact that the ball 71 is finally sandwiched between the insert 44 and the spring plate 83, combined with the elastic deformation capacity of said spring plate 83, allows said ball 71 to remain in contact with the cam profile. 41 without any compression spring being necessary. It therefore means that the ball 71 is simply slidably mounted along the lever 60.

Figures 8 and 9 correspond to a second embodiment of the invention, which is distinguished by the fact that the contact element 70 is constituted by a roller 72 substantially cylindrical, while the cam profile 41 is itself conventionally constituted by the outer periphery 45 of the fixed cam 40. It is understood here that the generatrices of the cylindrical roller 72 may be a priori any, that is to say, concave, convex or just straight.

In a complementary manner, the roller 72 has a side wall 73 whose curvature is substantially complementary to that of the outer periphery 45 of the fixed cam 40. We are here precisely in the case where the generatrices of the cylindrical roller 72 are not not strictly straight.

According to another characteristic of this second embodiment, the elastic return means 80 are able to drive the secondary shaft 30 in axial pivoting to a position corresponding to a contact between the roller 72 and the profile 41 of the fixed cam 40.

In this embodiment, the elastic return means 80 are in fact constituted by a cylindrical spring with angular action 84. The latter is implanted so that its body extends around the proximal end 34 of the secondary shaft 30, that one of its ends 85 abuts against the drive support 20, and that its other end 86 exerts a thrust force on the lever 60 of the control member 50.

Unlike the first previously described, the second embodiment has the advantage of not requiring the presence of any system able to compensate for variations in distance between the secondary shaft 30 and the effective contact point of the control member 50 on the cam profile 41. The roller 72 is in fact shaped and dimensioned so as to have a very large contact surface intended to cooperate by sliding with the cam profile 41. The concavity and the height of its side wall 73 are indeed chosen so as to always ensure an ∞ntact between the roller 72 of the mandrel member 50 and the fixed cam 40.

According to another feature of the invention, the drive support 20 is in the form of a housing 21 in which the fixed cam 40 and the control member 50 take place. This implies first of all that the assembly is arranged so that the primary shaft 10 and the secondary shaft 30 penetrates inside the housing 21. But the fixed cam 40 is destined to remain stationary relative to the rest of the control mechanism 1, this sub- also means that the assembly is arranged so that the housing 21 can rotate despite the presence of the fixed cam 40 therein.

This feature allows to consolidate most of the components of the control mechanism 1 within a relatively tight assembly to the outer elements and other soils. It is thus possible to significantly improve the reliability and the lifetime of the rotary control mechanism 1.

In this embodiment, the housing 21 is composed of a hollow body 22 whose opening is closed by a cover 23. These two elements are associated detachably. For this, the lid 23 is provided with four elastically deformable tabs 24 which are distributed at each of its sides, and which are able to come to fit after deformation on bosses 25 formed adequately to the outer surface of the body 22.

As can be seen in Figures 4 and 5, the housing 21 is also provided with sealing means 90 which are able to perfect its impermeability at the areas where are located the movable shafts 10, 30 Note in particular the presence of a first O-ring 91 which is positioned between the body 46 of the cam 40 and the cover 23, as well as a second O-ring 92 which is positioned for its part between the secondary shaft 30 and the body 22 of the housing 21.

According to another feature of the invention, the control mechanism 1 is further provided with indexing means 100 which are able to demobilize the drive support 20 in a reversible manner with respect to the fixed cam 40 (FIGS. 1 to 4). . This feature makes it possible to temporarily lock its various moving parts during the transport and storage phases, until the final assembly of the wiper device on the motor vehicle that is intended for it.

In this particular embodiment, chosen solely by way of example, the indexing means 100 comprise a pin 101 whose body is housed through a holding housing 102 formed in the cover 23, and whose end distal is able to sins in a locking hole 103 formed through the leg fixing 47.

But of course, any other locking system ∞nnu of the state of the art could be used in an equivalent manner.

More generally, the invention also relates to any wiper device comprising motor means capable of generating an alternating rotational movement, and a swing arm at the end of which is mounted a wiper blade, and further comprising a rotational control mechanism 1 as previously described, the drive means being coupled to the primary shaft 10 while the brush arm is integral with the secondary shaft 30.

However, more generally, the invention also relates to any motor vehicle having at least one wiper device as previously described.

Claims

claims

Rotating control mechanism (1), characterized in that it comprises:

a primary shaft (10) capable of being driven in alternating axial rotation,

a drive support (20) secured to the primary shaft (10),

a secondary shaft (30) mounted to rotate axially with respect to the drive support (20),

a fixed cam (40) having a specific profile (41),

- a control member (50) integral with the secondary shaft (30) and able to cooperate by sliding with the cam profile (41) during the displacement of the drive carrier (20) relative to the fixed cam (40); ), and in that the sliding of the control member (50) along the cam profile (41) is adapted to control the axial pivoting of the secondary shaft (30).

Control mechanism (1) according to claim 1, characterized in that the control member (50) comprises a lever (60), one end (61) is integral with the secondary shaft (30), a contact element (70) mounted freely in axial rotation on the lever (60), as well as elastic return means (80) able to hold the contact element (70) against the profile (41) of the fixed cam (40).

Control mechanism (1) according to one of claims 1 or 2, characterized in that the contact element (70) is further slidably mounted along the lever (60).

Control mechanism (1) according to one of claims 2 or 3, characterized in that the contact element (70) is constituted by a substantially spherical ball joint (71), and in that the cam profile (41 ) is in the form of a through groove (42) formed in the thickness of the fixed cam (40).

Control mechanism (1) according to claim 4, characterized in that the section of the groove (42) is substantially complementary to that of the corresponding portion of the ball (71).

Control mechanism (1) according to any one of claims 2 to 5, characterized in that the elastic return mo} ens (80) are adapted to drive the ball (71) moving along the lever (60) to a position of contact with the cam profile (41).

Control mechanism (1) according to one of claims 2 or 3, characterized in that the contact element (70) is constituted by a roller (72) substantially cylindrical, and in that the cam profile (41) is constituted by the outer periphery (45) of the fixed cam (40).

Control mechanism (1) according to claim 7, characterized in that the roller (72) has a side wall (73) whose curvature is substantially complementary to that of the outer periphery (45) of the fixed cam (40). ).

[0009] Control mechanism (1) according to one of claims 7 or 8, characterized in that the elastic spring return means (80) are capable of driving the secondary shaft (30) in axial pivoting to a contact position between the roller (72) and the cam profile (41).

Control mechanism (1) according to any one of claims 1 to 9, characterized in that the drive carrier (20) is constituted by a housing (21) inside which take place in particular the fixed cam ( 40) and the control member (50).

Control mechanism (1) according to claim 10, characterized in that the housing (21) comprises m} s sealing (90) able to seal particular areas crossed by the primary shaft 10 and by l secondary shaft 30.

[0012] Control mechanism (1) according to any one of claims 1 to 11, characterized in that it further comprises m} s indexing (100) able to reversibly immobilize the drive carrier (20). relative to the fixed cam (40).

Wiper device comprising motor units capable of generating an alternating rotational movement, as well as a brush-carrying arm at the end of which a wiper blade is mounted, characterized in that it further comprises a rotation control mechanism (1) according to any one of the preceding claims, in that the motor units are coupled to the primary shaft (10), and in that the brush arm is integral with the shaft secondary (30).

Motor vehicle, characterized in that it comprises at least one wiper device according to the preceding claim.