WO2010022769A1

WO2010022769A1 - Sunshade assembly and open roof construction provided therewith

Info

Publication number: WO2010022769A1
Application number: PCT/EP2008/061201
Authority: WO
Inventors: Marcel Johan Christiaan Nellen; Stephan Christiaan Vervoort
Original assignee: Inalfa Roof Systems Group B.V.
Priority date: 2008-08-27
Filing date: 2008-08-27
Publication date: 2010-03-04
Also published as: DE212008000124U1

Abstract

A sunshade assembly comprises a flexible sunscreen (4) having opposed longitudinal edges and opposed transversal edges, a rotatable winding' shaft (5) configured for winding and unwinding the sunscreen at a first one of its transversal edges, and an operating beam (8) connected to the second one of the transversal edges of the sunscreen. Elongated longitudinal guiderails (6, 7) each include a guide channel (11) in which the respective guide strip (10) is accommodated when the sunscreen is unwound. The guide channel is oriented at an acute angle transversely to accommodate the strips at an acute angle with respect to the sunscreen. The guide channel is bounded on the side facing the sunscreen by a guide edge (12) being in engagement with and guiding one of the sides of the flexible sunscreen.

Description

Sunshade assembly and open roof construction provided therewith

The invention relates to a sunshade assembly. A major field of application of sunshade assemblies of the type according to the invention is defined by open roof constructions for vehicles comprising a roof open- ing in a stationary roof part and a movable closure panel for opening and closing said roof opening, wherein below said roof opening there is provided such a sunshade assembly.

A known sunshade assembly comprises a rotatable winding shaft configured for winding and unwinding a sunscreen. An operating beam is connected to a free transversal edge of the sunscreen and is guided in guides extending along longitudinal sides of the sunscreen. A long torsion spring positioned inside the winding shaft loads latter in a direction for winding the sunscreen and for keeping the sunscreen taut.

Another known sunshade assembly is disclosed in EP 1 588 880 A2. In this document the flexible sunscreen is provided on its longitudinal axis with guide strips which act to guide the sunscreen in lateral direction and also act as a torsion spring to wind the sunscreen on the winding shaft .

It is an object of the present invention to further improve the prior art sunshade assembly. For this purpose, the sunshade according to the invention is characterized in that the guide channel is bounded on the side facing the sunscreen by a guide edge being in engagement with and guiding one of the sides of the flexible sunscreen. Due to this feature, the height position of the sunscreen will always be the same and it is also easier to obtain substantially constant frictional forces between the guide rails and the guide strips/sunscreen. Due to the engagement of the sunscreen by the guide edge it is made possible that the guide channels are dimensioned such that each guide strips has freedom of move^¬ ment in a direction within its plane and substantially per- pendicularly to its longitudinal extent. As a result, the guide strips may run free from the guide channels at their longitudinal edges which has a positive effect on the fric- tional forces.

The guide edge can be used to provide each guide strip with an equilibrium position within the guide channel in said direction substantially perpendicularly to the longitudinal extent, in which equilibrium position the portion of the sunscreen between the respective guide strip and its point of contact with the guide edge extends perpendicular to the main plane of the strip.

Due to this equilibrium position, the guide strip will always return to this position after an external distortion, when the sunscreen is subsequently moved and the static friction has thereby disappeared. This returning movement of the guide strips to their equilibrium position ensures that the equilibrium position, in which the fric- tional forces are relatively low, is obtained automatically and therefore the forces on the strip will be rather constant regarding external influences. Thus, the slide resis- tance in the guide remains substantially constant. This will prevent the guide strip from buckling or bending more than was foreseen, because the forces on the strip can be predicted and controlled.

To further reduce the frictional forces, it is preferred that the guide edge is rounded in cross section, preferably in both directions from the point of contact with the sunscreen. This minimizes the contact of the sunscreen with the guide edge and therefore the frictional forces.

In one embodiment the sunscreen is attached to the upper edge of the guide strip (i.e. the forces from the sunscreen act on the upper edge of the guide strip) , and it is preferred therein that the guide channel is shaped such that the guide strip, in its equilibrium position, is in contact with the guide channel only with its lower portion on the side facing away from the sunscreen in and with its upper portion on its side facing the sunscreen.

Due to these features, the guide channel is reduced to the portions that are actually used for guiding the guide strip. Due to the openness of the guide channel, the chances of particles becoming wedged between the guide strip and the guide channel are reduced.

Preferably at least a part of the flexible sunscreen is elastic, at least in transverse direction.

Due to this elasticity, stresses as a result of temperature differences and tolerances can be neutralized without resulting in a very high slide resistance. This is particularly the case if the elastic part of the sunscreen has a low spring constant so that a small tolerance or shrinking/expanding difference does not immediately lead to a high slide resistance. In a preferred embodiment, the guide strips are provided with means to provide rigidity in transverse direction and promote bendability along its length. Such means may comprise at least one of transverse grooves, ribs, slits, holes, slots, teeth, and the like. It is preferred to use means that create a small package when the guide strip is wound on the winding shaft.

The invention further relates to an open roof construction for a vehicle, comprising a roof opening in a stationary roof part and a movable closure panel for opening and closing said roof opening, wherein below said roof opening there is provided at least one sunshade assembly according to the invention.

Hereinafter the invention will be further elucidated with referring to the drawing schematically showing embodiments of the invention by way of example. Fig. 1 shows, schematically and in a perspective view, a sunshade assembly applied to an open roof construc^¬ tion;

Fig. 2 shows a transverse cross section according to the lines II-II in Fig. 1.

Figs. 3a, 3b and 3c show the guide strip of Fig. 3 in three different positions and showing forces on the guide strip.

Figs. 4a, 4b, 4c and 4d are views corresponding to that of Fig. 3 and showing embodiments of the guide channel with different angles of the guide strip.

Figs. 5, 6, 7, 8, 9 are views corresponding to that of Fig. 3 but showing further embodiments of the guide strip and guide channel of the sunshade assembly according to the invention.

Fig. 10a, b, c, shows a part of the flexible sunscreen and guide strip in three different positions.

Fig. 11-15 show different embodiments of a guide strip having means to provide rigidity in transverse direc- tion and promote bendability along the length.

Firstly referring to Fig. 1, an open roof construction for a vehicle is illustrated schematically in dotted lines. Said open roof construction comprises a roof opening 1 in a stationary roof part 2 of the vehicle, such as a passenger car, and a movable closure panel 3 which, by means not illustrated in detail but known per se, can be moved for opening and closing said roof opening 1. In Fig. 1 the closure panel 3 has been illustrated in a position in which it opens the roof opening 1. Below the roof opening 1 a sunshade assembly in accordance with the present invention is positioned. Basically, said sunshade assembly comprises a flexible sunscreen 4, a rotatable winding shaft 5 for winding and unwinding the sunscreen 4, and two opposite guiderails 6 and 7 for coop- eration with two opposite longitudinal edges of the sunscreen 4. In so far the sunshade assembly has a conventional shape. Further, in a way known per se, the end of the sun^¬ screen 4 opposite the end which is wound onto the winding shaft 5 is provided with an operating beam 8 which may be gripped manually for operating the sunscreen 4 and locating it in a desired position. The opposite ends of the operating beam 8 are guided in guides not illustrated here (extending along with or integrated into the guiderails 6, 7) . Now reference is made to Figs. 2 and 3. Fig. 2 shows a cross section of one transverse edge of the sunscreen 4 and of the guide rail 7. There is shown a side portion 9 of the sunscreen 4 which in this case is elastically stretchable at least in transverse direction (the remainder of the sunscreen may be substantially inelas- tic) . This portion 9 may be made from stretch textile such as fabric which is treated so as to obtain a low frictional resistance when sliding along the guide rail 6 or 7. It may also be made from other materials such as plastic or a rubber like material, or may be constructed as or provided with an elastic connection. Alternatively, the whole sunscreen may be made from stretch material or may have an elastic structure.

Attached to the lateral outer end of each side portion 9 of the sunscreen 4 is a guide strip 10, which is thus provided on each longitudinal edge of the sunscreen 4. This guide strip 10 is accommodated in a guide channel 11 of the guide rails 6, 7. The guide channel 11 is shaped such that the guide strip 10 is guided in the guide channel 11 with such orientation that it makes an acute angle with the main portion of the sunscreen 4 in transverse direction. In this embodiment, in which the sunscreen portion 9 is attached to the upper edge of the guide strip 10 (or at least the forces from the sunscreen are exerted on the upper edge) , the guide strip is only in contact with the guide channel in its upper portion on the side facing the sunscreen 4 (guide channel portion lla) and in its lower por- tion on its side facing away from the sunscreen 4 (guide channel portion lib) . In height direction, that is in a di^¬ rection perpendicular to the longitudinal axis of the guide strip 10 and within the plane of the guide strip 10, there is freedom of movement for the strip and normally the strip remains clear with its longitudinal edges from the upper and lower walls of the guide channel 11. The guide channel 11 is bounded on the side facing the sunscreen 4 by a guide edge 12 which, in the position shown in Fig. 2, is in contact with the lower side of the portion 9 of the sunscreen 4. At least the guide edge 12 and preferably the whole guide rails is made from a suitable low friction material such as aluminium or plastic. The guide edge and/or guide channel may be treated to further reduce frictional resistance. By means of Fig. 3 it is shown that the position according to Fig. 2 is an equilibrium position to which the guide strip 10 will return after it has been displaced by external influences, for example if somebody pushes against the sunscreen from below. Fig. 3 shows with arrows the forces exerted on the guide strip 10 in three different positions. Fig. 3a shows the position of the guide strip 10 when the sunscreen portion 9 is moved upwardly over a small distance. The force exerted by the elastic portion 9 of the sunscreen 4 on the guide strip is represented by arrow F which can be resolved in force Fi perpendicular to the plane of the guide strip 10 and force F₂ parallel to the guide strip 10. This latter force F₂ is directed downwardly as a result of the angled orientation of the guide strip 10 and urges the guide strip 10 back to its equilibrium position in which this force F₂ is zero (Fig. 3c) . In Fig. 3b, the strip is moved downwardly from its equilibrium position and in this downwardly moved position, there is a large upward force F₂ within the plane of the guide strip 10 urging it upwardly back to its equi- librium position. In the equilibrium position according to Fig. 3c, the combined forces on the guide strip 10 are at a minimum, so that the sliding behaviour is most favourable in this position, to which the guide strip 10 returns automati^¬ cally.

Fig. 4 shows the influence of the angle between the guide strip 10 and the sunscreen 4. In Fig. 4a, the guide strip 10 is at right angles to the sunscreen 4, which means that there is no returning force on the guide strip 10 when the guide strip 10 is moved from its normal position with the elastic portion 9 of the sunscreen 4 just in con- tact with the guide edge 12. Fig. 4b shows the guide strip 10 in a configuration of Fig. 3. This is more or less the angle at which there is a minimum force to return the guide strip to its equilibrium position. In Fig. 4c, the guide strip 10 is positioned under a more severe (acute) angle with respect to the sunscreen 4, thereby enlarging the returning force F₂ urging the guide strip 10 back to its equilibrium position. However, in this configuration, the friction between the lower side of the elastic portion 9 of the sunscreen 4 and the guide edge 12 will be increased due to the larger angle of contact. In Fig. 4d the angle between the guide strip 10 and the sunscreen 4 is increased, so as to reduce the angle of contact between the lower side of the elastic portion 9 of the sunscreen 4 and the guide edge 12. This is more or less a good compromise between friction at normal use and returning power of the guide strip. Of course, the angle will generally depend on the particular embodiment .

Figs. 5 and 6 show a comparison between resulting forces in two different embodiments of the guide strip 10 according to the invention. In Fig. 5, the arrangement is similar to that of Fig. 3, but in Fig. 6, the guide strip 10 has a curved shape in transverse direction, that is a curve which extends around a centre line parallel to the longitudinal direction of the guide strip 10. When this curved guide strip 10 is moved upwardly from its equilibrium position, the angle between the upper portion of the guide strip and the sunscreen 4 decreases, thereby increasing the re^¬ turning force F₂ urging the guide strip 10 back to its equi^¬ librium position. Of course, the guide channel 11 should be adapted to accommodate such curved guide strip 10. Figs. 7-9 show further comparisons between embodi^¬ ments Fig. 7 depicts the embodiment as shown in Figs. 5 and

3. In Fig. 8, the upper wall of the guide channel 11 is provided with a guide protrusion 13. This guide protrusion 13 is positioned oppositely to the guide edge 12 such that the elastic portion 9 of the sunscreen 4 extends between the guide edge 12 and the guide protrusion 13. In the equilibrium position, the elastic portion 9 is in contact with the guide edge 12, but in the upwardly displaced position according to Fig. 8, the elastic portion 9 of the sunscreen 4 comes in contact with the guide protrusion 13, which thereby exerts a returning force on the guide strip 10 through the elastic portion 9 of the sunscreen 4. As the guide protrusion 13 is positioned close to the guide strip 10, the angle between the guide strip 10 and the elastic portion 9 de- creases rapidly when the guide strip 10 moves upwardly, the returning forces F₂ are relatively large.

In Fig. 9 the guide protrusion 13 is slightly offset with respect to the guide edge 12 and has a position that is at a larger distance from the guide strip 10, so that the returning force F₂ is smaller than in the embodiment of Fig. 8.

In Fig. 10 some characteristics of the sunscreen

4, the elastic portion 9 and the guide strip 10 are illustrated. In Fig. 10a it is shown that the elastic portion 9 may be stretched from its original width X to its stretched width X₃ which is almost double the original width. In Fig. 10b, it is shown that in order to be able to wind the sunscreen 4 with the guide strip 10 onto the winding shaft 5, the guide strip 10 may be turned over to a position outside the elastic portion 9 in order to be wound together with the sunscreen 4 without forming a double layer. Guiding devices to turn over the guide strip to a position in extension of the sunscreen 4 are known in the prior art. Another possi^¬ bility for the guide strip 10 is to be turned over to the inside in order to be doubled with the elastic portion 9 of the sunscreen 4 and thus to be wound in a double layer (see Fig. 10c) . This is known from the prior art.

In order to ensure that the guide strip 10 is sufficiently rigid in transverse direction on the one hand and is sufficiently bendable in longitudinal direction on the other hand, the guide strip could be provided with means to accomplish this.

Figs. 11-15 show different embodiments thereof. Figs. 11, 12 and 13 show means to reduce the bending resistance in guide strips which are sufficiently rigid in trans- verse direction. Such means may comprise slots 14 (Fig. 11), holes 15 (Fig. 12), notches 16 (Fig. 13) and grooves 17 (Fig. 15) . Figs. 14 shows means that provide rigidity to guide strips 10 that are already sufficiently bendable. These means in this case include small ribs 18. Other means are conceivable.

From the foregoing it is clear that the invention provides a sunshade assembly which has a simple yet effective guide means for the sunscreen, which excels in low and constant friction properties. The invention is not limited to the embodiments described before, which may be varied widely within the scope of the invention as defined by the appending claims. For example, the closure panel can be replaced by one or more other closures, such as slats, a foldable cover or a plurality of panels. Furthermore, it is possible to drive the sunscreen electrically, for example by small electric motors which comprise drive wheels that engage the guide strips, in particular the means to provide rigidity, such as the slots or holes. Such electric drive is disclosed in the copending application of the same date, the contents of which are incorporated herein by reference thereto.

Claims

1. Sunshade assembly comprising: a flexible sunscreen having an upper and lower side, opposed longitudinal edges and opposed transversal edges, the longi^¬ tudinal edges being provided with guide strips which are bendable along its length and substantially rigid in transverse direction; a rotatable winding shaft configured for winding and unwinding the sunscreen and the guide strips at a first one of its transversal edges; and elongated longitudinal guiderails each including a guide channel in which the respective guide strip is accommodated when the sunscreen is unwound, the guide channel is oriented at an acute angle transversely to accommodate the strips at an acute angle with respect to the sunscreen; characterized in that the guide channel is bounded on the side facing the sunscreen by a guide edge being in engagement with and guiding one of the sides of the flexible sunscreen.

2. Sunshade assembly according to claim 1, wherein the guide channels are dimensioned such that the guide strips have freedom of movement in a direction within its plane and substantially perpendicularly to their longitudinal extent.

3. Sunshade assembly according to claim 1 or 2, wherein each strip has an equilibrium position within the guide channel in said direction substantially perpendicular to the longitudinal extent, in which equilibrium position the portion of the sunscreen between the respective guide strip and its point of contact with the guide edge extends perpendicular to the main plane of the strip.

4. Sunshade assembly according to claim 2 or 3, wherein the strip is spaced from the upper and lower edge of the guide channel when the strip is in its equilibrium position.

5. Sunshade assembly according to any of the previous claims, wherein the sunscreen is free from the guide edge between the point of contact with the guide edge and the point of attachment to the respective guide strip in its equilibrium position.

6. Sunshade assembly according to any of the previous claims, wherein the guide edge is rounded in cross section, preferably in both directions from the point of contact with the sunscreen.

7. Sunshade assembly according to any of the previous claims, wherein the sunscreen is attached to the upper edge of the strip.

8. Sunshade assembly according to claim 7, wherein the guide channel is shaped such that the guide strip, in its equilibrium position, is in contact with the guide channel only with its lower portion on the side facing away from the sunscreen and with its upper portion on its side facing the sunscreen.

9. Sunshade assembly according to anyone of the preceding claims, wherein at least a part of the flexible sunscreen is elastically stretchable, at least in transverse direction.

10. Sunshade assembly according to claim 9, wherein the sunscreen comprises a main part, which is sub- stantially inelastic, and connection portions between the main part and the guide strips, which are stretchable and are in contact with the guide edge of the guiderails.

11. Sunshade assembly according to anyone of the preceding claims, wherein the strip is substantially straight in cross section.

12. Sunshade assembly according to anyone of the preceding claims, wherein the guide strips are provided with means to provide rigidity in transverse direction and to promote bendability along its length.

13. Sunshade assembly according to claim 12, wherein the means comprises at least one of transverse grooves, ribs, slits, holes, slots, teeth or the like.

14. Open roof construction for a vehicle, comprising a roof opening in a stationary roof part and a movable closure panel for opening and closing said roof opening, wherein below said roof opening there is provided at least one sunshade assembly according to any of the preceding claims .