Patent Description:
Such an open roof construction is known e.g. from <CIT> or from <CIT> and comprises a light guide in a guide rail for a sunscreen device, the light guide fits into a cavity of the guide rail and emits light into a narrow gap towards the part of the sunscreen device which is visible for the occupants in the interior of the vehicle.

This prior art lighting device works well when the sunscreen is closed and thus the lower side of the sunscreen is illuminated, it does not give satisfying results if the sunscreen is opened.

<CIT> discloses an open roof construction in which the guide rail comprises a light guide. On one hand, an opening in the guide rail guides light from the light guide to a sunscreen on the one hand and light pipes direct light from the light guide vertically downwardly on the other hand to act as spotlights.

In view of the above it is an object of the present invention to solve the above-described problem and to provide an improved open roof construction.

In accordance with the present invention the open roof construction is characterized by the features of the characterizing portion of claims <NUM>.

According to the invention, the light guiding device directs light in two directions, one will result in an illumination of the closed sunscreen, the other will provide an (indirect) illumination of the interior when the sunscreen is opened. The light will preferably be directed such that the panel of the open roof construction is never illuminated directly from below to prevent reflection of light in the panel when the sunscreen is open.

In one embodiment, the first light guide comprises means to direct light in two different directions.

This is the simplest solution since only one light guided is needed for the two lighting modes.

One of the possibilities to direct light in two directions is to use means that include a non-transparent shield partly surrounding the first light guide.

In this way, the shield can be used to block light in all but two (or more if desired) directions.

The shield may include transparent windows at the positions where light must be directed out of the first light guide to allow maintaining an integral shield, but at least one of the windows of the shield may be open to be able to use this opening to introduce the light guide into the shield in a direction perpendicularly to it, in particular if the shield is a part clamped around the first light guide.

In another embodiment, the shield is co-extruded with the first light guide, which simplifies the assembly.

Instead of or in addition to the shield, the means may include light directing members on the outer circumference of the first light guide directing light out of the first light guide at a position opposite to the light directing members.

The light directing members may include at least one of a prism, or a light reflecting print or co-extrusion on the circumference of the first light guide.

To further block light the shield of each light guiding device may include a projecting part above the window directing light towards a central part of the sunscreen. Such projecting part may be used to prevent light coming from the light guide to reflect on the transparent panel, typically made from glass or plastic.

In a particular embodiment, the light guiding device includes a second light guide directing light to an upright cover covering at least a part of the area between the respective guide rail and the panel.

Although such cover may also be used in the embodiment with only the first light guide, one can create more special effects if a separate second light guide is used, for example with an integrated cover, for example formed by a part of the shield. The second light guide itself may also be provided with an upright projection directing light from the second light guide directly to the interior. Such second light guide will generally be positioned above the level of the sunscreen.

In order to attach the first and/or second light guide to a stationary part of the open roof construction, it may include an attachment to attach the shield to the guide rail. To further integrate the shield with the guide rail, a part of the shield may form a sliding surface for the sunscreen.

The first and/or second light guide may be either a solid core or a bundle of light guiding fibres surrounded by a cladding.

Hereinafter the invention will be elucidated while referring to the drawing.

<FIG> shows a part of vehicle, in this case a passenger car, comprising an open roof construction in its fixed roof <NUM>. The open roof construction comprises a transparent or semi-transparent panel <NUM> (or a panel with variable transparency) which is able to close or at least partly open a roof opening <NUM> in fixed roof <NUM>. The open roof construction further comprises along and below each (left and right) longitudinal edge <NUM> of roof opening <NUM> a guide rail <NUM>. The panel <NUM> is slidably guided in an outer part <NUM> of guide rail <NUM> and is also movable in vertical direction in order to enable panel <NUM> to slide above or below fixed roof <NUM>. Adjacent to, in this case behind, movable semi-transparent panel <NUM> there is arranged a second panel <NUM>', this panel may be a fixed panel and may be semi-transparent like front panel <NUM>. However it may be conceivable as well that second panel <NUM>' is also a movable panel for instance it may be a tiltable panel.

The open roof construction further comprises a retractable sunscreen device <NUM>, comprising a flexible cloth like sunscreen <NUM> or a rigid plate sunscreen both of which are retractable, such that in a retracted or open mode, light coming from the exterior side of the vehicle may enter an interior space <NUM> in the vehicle, and daylight is blocked when sunscreen device <NUM> is in an extended or a rolled-out mode. The retractable sunscreen <NUM> is slidably guided in a pair of the guide rails <NUM>.

In <FIG> the open roof construction is shown partly whereby first and second panels <NUM>, <NUM>' are omitted for clarity and only a basic frame <NUM> of the open roof system is shown comprising one of guide rails <NUM>. The retractable sunscreen <NUM> is shown as a rollo comprising a flexible cloth 8A and an operating beam 8B. Below each of first and second panels <NUM>, <NUM>' there may be a light guiding device <NUM>. The light guiding device <NUM> may be attached to guide rails <NUM> and may extend along the complete length of guide rails <NUM> or only for a part. In <FIG> it should be understood that two separate light guiding devices <NUM> are arranged at each left and right side of mirror-imaged guide rails <NUM>, such that each of light guiding devices <NUM> extend over the length of a longitudinal edge of one or each of panels <NUM>, <NUM>'. Each light guiding device <NUM> comprises at least a first light guide <NUM> for guiding light from a light source <NUM> (<FIG>) to interior space <NUM> in the vehicle. Such a light guiding device <NUM> is shown in <FIG>.

In <FIG> a part of guide rail <NUM> is shown and further showing a part of flexible sunscreen <NUM> which is kept in a groove <NUM> of guide rail <NUM> by means of a folded edge part <NUM> of flexible sunscreen <NUM>. Adjacent and below sunscreen <NUM> guide rail <NUM> is equipped with light guiding device <NUM>. In this embodiment, the upper side of light guiding device <NUM> is substantially at the same level as the bottom of groove <NUM>. This means that a part of light guiding device <NUM> can act as a support for sunscreen <NUM>, which will be further elucidated later on.

The light guiding device <NUM> comprises the first light guide <NUM> here consisting of a solid transparent core which is able to transmit light that is introduced into the light guide <NUM> at one or both ends by one or more of said light sources <NUM> (not shown here). The first light guide <NUM> extends substantially parallel to the respective guide rail <NUM>, <NUM> and therefore generally also follows any curvature thereof. In the embodiment shown, the cross-section of the first light guide <NUM> is circular, however, other cross-sections are conceivable, such as polygonal, e.g. rectangular or square, in which edges could be rounded to avoid bright lines at the sharp edges.

In the first embodiment of <FIG> and <FIG>, light guide <NUM> is surrounded by a light blocking (non-transparent) shield <NUM> having a first window <NUM> and a second window <NUM>. Light guide <NUM> is able to direct light through first window <NUM> towards a central part of sunscreen <NUM>, in particular when this is closed, and to direct light through second window <NUM> to parts above groove <NUM> of guide rail <NUM>, a seal <NUM> mounted on guide rail and a reinforcement <NUM> below panel <NUM> cooperating with seal <NUM> when panel <NUM> is in its closed position. These parts can only be illuminated if sunscreen is retracted or rolled-up on its winding roller.

It is shown in <FIG>, <FIG> that shield <NUM> is equipped with a projecting part <NUM> projecting towards the centre of sunscreen <NUM>. The length of projecting part <NUM> is such that light is blocked in the direction of panel <NUM> thereby preventing reflection of light by panel <NUM> when sunscreen <NUM> is retracted. Due to the height of the upper side of shield <NUM> and in this case also of its projecting part <NUM>, the shield <NUM> can be used to support and guide sunscreen <NUM>. The material of shield <NUM> can be chosen such that it has good sliding properties.

Light guide <NUM> may e.g. be made of transparent PMMA, while shield <NUM> could be made of white coloured PMMA with a low light efficiency. The light guide <NUM> and shield <NUM> could be made by co-extrusion, but it would be best to have some kind of surface separation to minimize light entering shield <NUM>.

In the embodiment of <FIG>, the surface separation is accomplished by means of small distance holders <NUM> on the outer surface of light guide <NUM>.

<FIG> shows an embodiment where light guide <NUM> and shield <NUM> are separate parts. Windows <NUM>, <NUM> could be transparent parts of shield <NUM> formed by co-extrusion. However, windows <NUM> could also be left open, and as a result, light guide <NUM> could be inserted into shield <NUM> from the side through window <NUM>, instead of being inserted from an end of shield <NUM>. Shield <NUM> could then be fixed on light guide <NUM> by a clamping fitting. Other means of attachment could be welding, gluing etc..

In the <FIG> embodiment, light guide <NUM> is not a solid core, but comprises a plurality of fibres 23A bundled together by means of a cladding 23B. Shield <NUM> is formed as a separate element.

<FIG> shows an embodiment in which cladding and shield are integrated and thus shield <NUM> as shown also functions as cladding for the fibre bundle light guide <NUM>.

<FIG> shows another embodiment in which shield <NUM> is left out and in which light guide <NUM> is provided on its outer surface with two prisms <NUM>, <NUM> at a position <NUM> degrees opposite to the position of windows <NUM>, <NUM>. Prisms <NUM>, <NUM> direct the light internally away to the other side, so that the same effect is accomplished as in the former embodiments. The prisms <NUM>, <NUM> can be formed by or replaced by e.g. a light reflecting print, a rough texture or co-extrusion on the circumference of the first light guide co-extrusion or the like (<FIG>).

<FIG> shows that the embodiment of <FIG> can also be combined with shield <NUM> precluding any light from leaving light guide <NUM> at a non-desired position.

The light guiding device <NUM> in the embodiment of <FIG> comprises not only first light guide <NUM> but also a second light guide <NUM>. Second light guide <NUM> is arranged above the level of sunscreen <NUM>. Light guides <NUM>, <NUM> both receive light from the same light source <NUM>, for example a LED light source. Of course, the light guides <NUM>, <NUM> could also receive light from different light sources. The cross-section of the light guide <NUM> and/or <NUM> at the position of the light source(s) could be different from that where the interior is illuminated. Also in the latter position, the cross section could vary along the length.

Each light guide <NUM>, <NUM> illuminates its own area, in this case first light guide <NUM> illuminates the lower side of sunscreen <NUM> and second light guide <NUM> the area between sunscreen <NUM> (or groove <NUM> of guide rail <NUM>) and panel <NUM>. For this purpose, light guide <NUM> has a projecting part <NUM> protruding in a substantially vertical direction. Thus, light guide <NUM> emits light from this area instead of illuminating this area and thus indirectly emitting light therefrom. This latter would also be possible of course. Such a vertical projecting part <NUM> may also have a function as a cover which protects against objects being trapped by a slidable mechanism for opening and closing one or both of the first and second panels <NUM>, <NUM>'. The vertical projection <NUM> is covered by a shield <NUM>' at its side facing outer part <NUM> of guide rail <NUM>, said shield <NUM>' thereby forming a part of the cover.

<FIG> show two embodiments in which light guiding device <NUM>, and in this case shield <NUM> thereof is integrated in guide rail <NUM> and also performs an additional function already mentioned above. This additional function is to support and guide sunscreen <NUM> from below without resting on a part of guide rail <NUM>. For this purpose, shield <NUM> is provided with an attachment portion <NUM> with which shield <NUM> is attached to an (upright) wall of guide rail <NUM>, e.g. by means of a rivet <NUM> or by any other suitable means, such as screwing, gluing, welding etc. In the embodiment of <FIG> shield <NUM> also forms a lower wall of groove <NUM> for folded edge part <NUM> of sunscreen <NUM>.

Claim 1:
Open roof construction for a vehicle, comprising at least one at least semi-transparent panel (<NUM>) for closing an opening (<NUM>) in a fixed roof part (<NUM>) of the vehicle, a retractable sunscreen device (<NUM>) capable of blocking daylight entering through the panel, said sunscreen device including a sunscreen (<NUM>) slidably guided in a pair of guide rails (<NUM>) each extending below and along a longitudinal edge (<NUM>) of the opening in the fixed roof in a longitudinal direction, a light guiding device (<NUM>) attached to each of the guide rails, said light guiding device comprising at least a first light guide (<NUM>) for guiding light from a light source (<NUM>) to an interior space (<NUM>) in the vehicle, wherein said light guiding device (<NUM>) on each of the guide rails (<NUM>) comprises means (<NUM>, <NUM>; <NUM>, <NUM>) to direct light at least in two different directions, one direction is towards a central part of the sunscreen (<NUM>), characterised in that the other direction is towards or from an area between the respective guide rail (<NUM>) and the panel (<NUM>) such that this light provides an illumination of the interior space (<NUM>) only when the sunscreen (<NUM>) is retracted.