FR3069507B1 - MANET-CRANK ASSEMBLY OF A MOVEMENT TRANSMISSION MECHANISM OF A WIPER SYSTEM - Google Patents

Abstract

The invention proposes an assembly belonging to a movement transmission mechanism for driving in rotation a motor vehicle wiper, this assembly comprising a crank (40) and an axially oriented crankpin (42) (A). ) which is carried by the crank (40) and of which an axial section (80) is received in a hole (60) of the crank (40), characterized in that the crank (40) is retained axially on the axial section ( 80) of the component (42) by a retaining piece (90), a portion of which is received radially in a complementary housing of the axial portion (80) of the component (42).

Description

Crankpin assembly of a motion transmission mechanism of a windscreen wiper system

TECHNICAL FIELD OF THE INVENTION The invention relates to an assembly such as a crank pin assembly belonging to a motion transmission mechanism, such as a wheelhouse, for driving a windscreen wiper in rotation.

BACKGROUND OF THE INVENTION The invention relates to a motion transmission mechanism of the type comprising a rotating shaft rotatably connected to a first end of a crank whose second end carries a crankpin which is intended to be connected to a connecting rod. via a spherical box, for example a driving link, belonging to a linkage of motion transmission for driving in rotation of a motor vehicle wiper.

The design of the assembly comprising the crank, the crankpin extending in a generally axial direction substantially orthogonal to the plane in which the crank extends, and the rotating shaft which also extends in a generally axial axial direction orthogonal to the plane in which the crank extends, is such that the crankpin and the bearing shaft must be rotatably connected to the crank and reliably attached thereto.

For example, for the crankpin-crank connection, an axial portion of the crank pin is received axially through a complementary hole in the crank and is immobilized axially with respect to the crank. In known manner, the axial section is for example mounted by crimping in the complementary hole.

The crankpin and the crank thus form a structural subset.

The crank-drive shaft connection can also meet the same design.

When the three crankpin-crank-drive shaft components are thus assembled into a non-dismountable assembly, the assembly operations of the wheelhouse to which such a unit belongs may be complex, in particular depending on the environment of the vehicle in which the wheelhouse and other components and subassemblies of a wiper drive system shall be installed. The aim of the invention is to propose a new design of the connection between the crank and an axially oriented component, such as the crankpin or the drive shaft, making it easier to assemble the aforementioned mechanisms for transmitting motion. previously.

The object of the invention is also to facilitate mounting between the crank and an axially oriented component, such as the crankpin or the drive shaft during delivery of the components of the transmission mechanism at the car manufacturer. In this case, the crankpin already being mounted in the ball joint which is itself housed in the rod, it was necessary to find a way to bind and fix quickly and reliably the crank and an axially oriented component, such as the crankpin or the drive shaft.

BRIEF SUMMARY OF THE INVENTION The invention proposes an assembly belonging to a mechanism for transmitting motion for driving a motor vehicle wiper in rotation, this assembly comprising a crank and an axially oriented component which is carried by the crank and of which an axial section is received in a hole of the crank, characterized in that the crank is retained axially on the axial portion of the component by a retaining piece of which a portion is received radially in a complementary housing of the section axial component.

According to other features of the invention: the portion of the retaining piece is received in a groove of the axial portion of the component; the portion of the retaining piece comprises two opposite branches each of which is received in an associated groove of the axial section; - the retaining piece is a split elastic ring; - The retaining piece is carried by the crank relative to which it is mounted radially movable between a retracted position for mounting the crank on the component, and an active axial retention position of the crank relative to the crankpin or the crank. drive shaft; - The retaining piece comprises a handling rod of the retaining piece which is guided in sliding on the crank; - The handling rod comprises an abutment surface which, when the retaining piece is in the active position for retaining the component, cooperates with a bearing surface vis-à-vis the crank; - The crank comprises a sliding guide window of the handling rod of the retaining piece which is arranged opposite the hole; - The retaining piece is carried by the crank captively; the axial portion of the component is connected in rotation to the crank; - The axial portion of the component has a non-revolution contour and a portion is received axially in the hole whose contour is complementary; the groove belongs to a portion of a radial groove; - The assembly comprises a connecting rod, and the component is a crankpin which is mounted articulated on the connecting rod; - The crank pin comprises a hinge joint which is housed in a ball joint carried by the connecting rod; - The component is a drive shaft of a wiper.

BRIEF DESCRIPTION OF THE FIGURES Other features and advantages of the invention will emerge during the reading of the following detailed description for the understanding of which reference will be made to the appended drawings in which: FIG. 1 is a perspective view which illustrates an exemplary design of a wiper rotation drive system which comprises a crank-crank assembly according to the invention; - Figure 2 is a perspective view on a larger scale which shows the crank-crank assembly of Figure 1 in association with an associated end portion of the connecting rod connected to the crank pin; - Figure 3 is a view similar to that of Figure 2 without the connecting rod; - Figure 4 is a top view of the crank belonging to the crank-crank assembly of the preceding figures; FIG. 5 is a perspective view of the crankpin belonging to the crankpin assembly of the preceding figures; FIG. 6 is a view from below of the elements illustrated in FIG. 2; - Figure 7 is a detail view in section along the vertical plane 7-7 of Figure 4; - Figure 8 is a detail view in section along the vertical plane 8-8 of Figure 6; - Figure 9 is a detail view in section along the vertical plane 9-9 of Figure 4; FIGS. 10A to 10D are bottom views which illustrate various stages of assembly of the elements belonging to the crank pin assembly illustrated in the previous figures; - Figure 11 is a perspective view similar to that of Figure 3 which illustrates an alternative embodiment of the retaining piece of the crank pin; and - Figure 12 is a perspective view of the retainer shown in Figure 11.

DETAILED DESCRIPTION OF THE FIGURES

In the remainder of the description, elements having identical structure or similar functions will be designated by the same references.

In the remainder of the description, without reference to terrestrial gravity, the longitudinal, vertical and transverse orientations indicated by the "L, V, T" trihedron of the figures will be adopted in a nonlimiting manner. We also define a horizontal plane that extends longitudinally and transversely.

The windscreen wiper drive system 20 (not shown) of FIG. 1 comprises in particular a geared motor 22 comprising an output shaft 24 which constitutes here a first drive shaft for a first windscreen wiper ( not shown) a drive arm is adapted to be fixed on the upper free end section 26 of the drive shaft 24.

FIG. 1 also shows a plate 23 for mounting and fixing the gear motor 22 on a motor vehicle.

The system 20 comprises a connecting rod 30 for transmitting the rotational movement of the output shaft 24 of the geared motor 22 to a second shaft 32 driving in rotation a second wiper (not shown), including an arm The drive is adapted to be fixed on the upper free end section 34 of the drive shaft 32.

The connecting rod 30 has a first end 29 which is connected to the output shaft 24 by a first crank 36 which is rotatably connected to the output shaft 24.

The first crank 36 carries a first axially oriented crank pin 38 to which it is connected in rotation.

The first crank pin is connected to the first end 29 of the connecting rod 30 by a connection of the type of ball joint known design not shown in the figures.

The connecting rod 30 has a second end 31 which is connected to the drive shaft 32 by a second crank 40 which is rotatably connected to the drive shaft 32.

The second crank 40 carries a second pin 42 (not visible in Figure 1) of axial orientation to which it is connected in rotation.

The second crankpin 42 is connected to the second end 31 of the connecting rod 30 by a connection of the known type of ball joint.

Finally, there is shown in Figure 1 a support 33 for mounting and guiding in rotation of the second drive shaft 32 on the motor vehicle.

As illustrated in detail in FIG. 2 and following, the crank 40 is in the form of a sheet metal plate cut and stamped 44.

The plate 44 is defined by an upper face 46 and a lower face 48.

The plate 44 is of rectangular general contour which is delimited by two opposite longitudinal edges 50 and by two convex rounded opposite end transverse edges 52 and 54 including a proximal edge 52 and a distal edge 54.

As can be seen in particular in FIGS. 6 to 9, the edges 52, 54 and 56 are successive portions of a continuous vertical edge which extends downwards from the horizontal plane of the plate 44.

This vertical edge gives the crank 40 a very high rigidity while allowing to achieve the latter by cutting and stamping in a sheet of suitable thickness.

The crank 40 has a general design symmetry with respect to a median vertical and longitudinal plane PVM.

In the vicinity of its distal end edge 56, and in a transversely centered manner, the plate 44 of the crank 40 comprises a hole 58 of square section which is designed to receive an axial section (not shown in the figures) which is a lower section the second drive shaft 32 of complementary section which is fixed for example by crimping.

The hole 58 is made by cutting into the plate 44.

In the vicinity of its proximal end edge 54, and in a transversely centered manner, the plate 44 of the crank 40 comprises a hole 60 of rectangular section with rounded corners which is designed to receive a complementary axial portion of the associated crank pin 52.

The hole 60 belongs to a projecting portion 62 which is made by stamping and which extends vertically projecting upwards above the upper face 46 of the plate 44.

The protruding portion 62 is delimited by a planar annular upper surface 64 which surrounds the hole 60 and which extends in a horizontal plane parallel to the general plane of the crank 40.

In the vicinity of its proximal end edge 54, each of the longitudinal edges 52 has a rectangular window 66 made by cutting.

The two windows 66 are aligned transversely and are aligned with the rectangular hole 60.

Each window 66 is delimited longitudinally by two opposite vertical edges 68 which define the width "I" of the window 66.

Each window 66 is delimited vertically upwards by an upper edge 70 coplanar with the lower face 48 of the plate 44 and by a lower edge 72 which, with the upper edge 70, defines the height "h" of the window 66.

The crank pin, shown in detail in Figure 5, is an axially oriented component along a central axis "A". The general axis A of the crankpin 42 corresponds to the vertical axis of the trihedron L, V, T and is oriented from bottom to top.

The crank pin 42 has an upper portion 74 in the form of a portion of a spherical ball centered on the axis A.

This upper portion is defined axially downwards by a radial annular surface 76 facing downwards.

Beyond the annular surface 76, the crank pin 42 comprises a circular cylindrical lower section 80 which is delimited by a lower end radial face 78 and a circular cylindrical lateral wall 82.

The lower section 80 comprises two opposite flat surfaces 84 parallel to the central axis A and parallel to them which extend here over the entire axial height of the lower section 80.

The dimensions of the lower section 80 and the arrangement of the flats 84 are such that the lower section 80 has, in section by a horizontal plane, a generally rectangular contour with two rounded sides which is complementary to that of the crank hole 60 40.

Thus, the lower portion 80 of the pin 42 can be introduced axially, here from top to bottom, in the hole 60, with a slight radial clearance, until the axial abutment of the annular surface 76 on the flat annular upper face 64 of the crank 40 which surrounds the hole 60.

As the concave internal contours of the hole 60 and external convex of the lower section 80 are not of revolution, this ensures a connection in rotation between the crankpin 42 and the crank 40.

These contours can be of any suitable profiles immobilizing the crankpin in rotation relative to the crank.

The lower portion 80 of the crank pin 42 has an internal radial groove 86.

Due to the presence of the flats 84, the radial groove 86 forms two diametrically opposed grooves 88 whose bottom is a convex circular cylinder section.

The groove 86 is formed at a vertical dimension determined relative to the annular surface 76 so that, as can be seen in particular in Figures 7 to 9, the groove 86 is located substantially immediately below the lower face 48 of the plate 44 at the same height as the windows 66.

The axial height of the groove 86 is also substantially equal to the height "h" of the windows 66.

When the lower portion 80 of the crankpin 42 is mounted in the hole 60 of the crank 40, each groove 88 extends substantially transversely facing the windows 66.

To retain axially the crank pin 42 relative to the crank 40, there is provided a retaining piece 90 which, by way of non-limiting example, is here produced in the form of a split elastic ring capable of being received in the throat radial radial 66 of the lower portion 80 of the crank pin 42. The split elastic ring is of circular general contour delimited by an inner concave cylindrical wall 92 and an outer convex cylindrical wall 94. The elastic ring is split and radially open with two chamfered legs 95 mounting. The split elastic ring thus has two branches in a circular arc opposite diametrically. The axial thickness of the split elastic ring is slightly less than the height of the radial groove 86 and the windows 66 so as to allow its transverse insertion through one or the other of the two windows 66, then into the groove 86.

As can be seen in FIGS. 7 to 9, in the mounted position of the split elastic ring, the lower section 80 is retained axially without play or almost without clearance with respect to the plate 44 of the crank 40.

In order to facilitate the handling and implementation of the split retaining elastic ring, the latter is here provided with a shank or shank 96 for gripping and manipulation which extends the split elastic ring in the plane of the latter.

The rod 96 is in the form of a hairpin with two branches 98 each of which is extended by a branch in an arc of the split elastic ring.

The rod 96 is elastically deformable in such a way that the two branches 98 can be brought closer to one another (according to the arrows F2 of FIG. 10A) or spaced apart from one another in the horizontal plane in which they extend.

The branches 98 of the rod 96 are coplanar with the split elastic ring and are dimensioned so that they can be received simultaneously in one or the other of the windows 66 and slide there freely or with a slight friction, depending on the direction cross.

As can be seen in Figures 10A and 10B, the elastic approximation of the two branches 98 reduces the outer diameter "overall" of the split elastic ring to allow its transverse introduction through one or the other of the two windows 66 .

The mounting and fixing of the crankpin 42 on the crank is illustrated in FIGS. 10A to 10D.

The crank 40 is first equipped with its retaining elastic retaining ring by introducing the latter as illustrated in FIG. 10A.

By introducing the tabs 94 into a window 66 and then pushing transversely on the rod 96 (along arrow F1 of FIG. 10A), the outer convex cylindrical wall 94 of the split elastic ring cooperates with the lateral edges of the window 66 which causes a radial compression of the ring according to the arrows F2 of Figure 10A until the crossing of the window to reach the position and the relaxed state illustrated in Figure 10B. The split elastic ring is then retained under the lower face 48 of the plate 44 and the rod 96 can slide transversely in the window 66. Without limitation, the design shown makes the elastic ring split with its handling rod 96 mounted in a "captive" manner "under" the crank 40.

This is achieved because the overall length L1 of the split elastic ring with its shank 96 is greater than the internal distance L2 separating the two opposite longitudinal edges 50 as shown in FIG. 10B.

As illustrated in Figure 10C, it is necessary to introduce the lower portion 80 of the crank pin 42 into the hole 60 to bring the face 64 and the surface 76 in contact with each other.

It is then possible to push transversely on the handling rod 96 according to the arrow F3 of FIG. 10C to cause the elastic engagement of the split ring in the grooves 88 defined by the internal radial groove 86.

The reduction in the length of the portion of the handling rod 96 located outside the crank 40 attests to the setting in active position said retention of the elastic ring split in the groove 96.

It is also possible to provide marking means on the outer surface of the handling rod 96 representative of different transverse positions of the split elastic ring relative to the hole 60 and / or relative to the lower portion 80 of the crankpin 42.

According to the variant embodiment illustrated in FIGS. 11 and 12, the handling rod 96 may be modified to include a section 97 bent at right angles to the horizontal plane of the split elastic ring and the handling rod 96.

Thus, the transverse position of the bend is such that the operator brings the bent section 97 bearing by its face 99 against the portion vis-à-vis the longitudinal edge 50 in which is formed the associated window 66 to reach the active position of the split elastic ring.

In addition, the bent section 97 facilitates the gripping and the operation of the handling rod 96. The split elastic ring, with or without its bent section, can be introduced indifferently into one or other of the windows 66.

In known manner, as can be seen in FIG. 8, the upper section 74 or head in the form of a ball is housed, and lubricated in a sealed manner in the inner housing 100 of a spherical box 102 which is itself carried by the second end 31 in the form of a plate of the connecting rod 30 which has a hole 104 provided for this purpose.

In the case of the arrangement of a system such as that illustrated in FIG. 1, the implementation of the invention makes it possible to deliver the system 20 in three parts, thus being able to carry out the assembly and fixing of the second end. 31 of the rod equipped with the spherical box 102 and the crank pin 42 by inserting the crank pin 42 into the crank 40 connected to the second drive shaft 32 carried by the support 33.

According to an embodiment not shown, the principle according to the invention can be implemented in the same way to achieve the connection and the attachment between the lower section of the second drive shaft 32 and the crank 40.

Claims (14)

An assembly belonging to a motion transmission mechanism (20) for rotating a motor vehicle windscreen wiper, said assembly comprising a crank (40) and an axially oriented component (42) (A). ) which is carried by the crank (40) and an axial portion of which is received in a hole (60) of the crank (40), characterized in that the crank (40) is retained axially on the axial portion (80) of the component (42) by a retaining piece (90), a portion of which is received radially in a complementary housing of the axial portion (80) of the component (42), said retaining piece (90) being carried by the crank (40) by ratio to which it is radially movable between a retracted position and an active retaining position. 2. An assembly according to claim 1, characterized in that the portion of the retaining piece (90) is received in a groove (88) of the axial portion (80) of the component (42). 3. An assembly according to claim 2, characterized in that the portion of the retaining piece (90) comprises two opposite branches each of which is received in an associated groove (88) of the axial section (80). 4. The assembly of claim 3, characterized in that the retaining piece (90) is a split elastic ring. 5. An assembly according to any one of the preceding claims, characterized in that the retaining piece (90) comprises a rod (96) for handling which is slidably guided on the crank (40). 6. An assembly according to claim 5, characterized in that the rod (96) for manipulation comprises an abutment surface (99) which, when the retaining piece (90) is in the active position of retaining the component (42), cooperates with a support surface vis-à-vis (50) of the crank (40). 7. An assembly according to any one of the preceding claims, characterized in that the crank (40) comprises a window (66) slidably guiding the rod (96) for handling the retaining piece (90) which is arranged facing said hole (60). 8. An assembly according to any one of the preceding claims, characterized in that the retaining piece (90) is carried by the crank (40) captively. 9. An assembly according to claim 1, characterized in that the axial portion (80) of the component (42) is rotatably connected to the crank (40). 10. The assembly of claim 9, characterized in that the axial portion (80) of the component (42) has a contour which is not of revolution and a part of which is received axially in said hole (60) whose contour is complementary. 11. The assembly of claim 2 or 3, characterized in that said groove (88) belongs is a portion of a radial groove (86). 12. An assembly according to any one of the preceding claims, characterized in that it comprises a connecting rod (30), and in that the component is a crankpin (42) which is pivotally mounted on the connecting rod (30). 13. The assembly of claim 12, characterized in that the crankpin (42) comprises a hinge ball which is housed in a ball joint (102) carried by the connecting rod (30). 14. Assembly according to any one of claims 1 to 11, characterized in that the component is a shaft (32) for driving a wiper.