This invention concerns a luminous false-wall device to be attached to a panel such as a wall or a ceiling. The invention thus pertains to the technical field of stretched false ceilings and false walls, behind which a light source is placed.
False-wall devices comprising a stretched canvas fixed at the base of a chassis frame, generally rectangular, which is made of an association of profiles forming each one of its sides, are known in the prior art. To this end, the canvas comprises an attachment means fixed along its periphery. For example, as described in patent FR 2,630,476, the canvas may be provided with a peripheral hook-shaped outer edge. Another attachment means consists in clips inserted in the profiles, in which the canvas may be secured by pinching. The stretched canvas may be, for example, a textile material or a synthetic polymer material, such as polyvinyl chloride (PVC). The light source illuminates the canvas, which is translucent so as the light may propagate through the canvas and lighten the room in which the luminous false-wall device is installed.
In particular, in an application of the light box type, the assembly canvas/frame is placed in an external frame provided with lateral sides, a bottom side and lighting means. In the latter case, the chassis is fixed to the external frame and the light emitted by the lighting means passes through the translucent canvas.
Whether a false ceiling, a false wall or a light box, the light intensity on the outer side of the canvas is sometimes insufficient relative to the desired effect. On the one hand, the translucent canvas generally has a transmittance in the order of 50%, meaning that 50% of the light intensity is lost. On the other hand, the source of light may be far away from the canvas, which weakens the intensity of light striking it.
Solutions consist in bringing the light source closer to the canvas, to multiply the number of light sources or to increase their power. However, the implementation of these solutions has drawbacks. Moreover, a minimal safety distance is required between the light sources and the canvas to avoid degrading it. In spite of these solutions, there remains a problem of insufficient light intensity.
On the other hand, the profiles forming the chassis generally have a rectangular cross-section, with an upper side facing the wall or ceiling and a lower side facing the canvas. The canvas covers generally the entire lower side of the profile. Thus, when the stretched canvas is observed, the lower side of the profile is visible by transparency or by the shadow they cast on the canvas, creating an unsightly shaded area on all the perimeter of the chassis.
A known solution, described in patent EP 2,494,121, consists in using profiles with a triangular cross-section, with the tip directed toward the canvas and the two others edges are directed towards the wall or ceiling. In this way, only the tip directed toward the canvas can still be visible and the light may pass along the hypotenuse. This solution improves the lighting of the canvas's perimeter, but still does not allow a homogeneous lighting to be obtained on the whole of the canvas surface. Indeed, the profile itself, even if triangular in shape, still casts a shadow on the canvas, creating a shaded area along the perimeter of canvas, with a lighting intensity lower than the rest of the canvas.
The present invention aims at solving the various drawbacks mentioned above, by means of a device allowing to generally increase the intensity of light which passes through the canvas, and to homogenize the light intensity over the whole of the canvas surface area, while suppressing the conventional shaded area at the periphery. The device must simple to implement, and adaptable to a false wall, a false ceiling and a light box alike.
This aim is achieved by a luminous false-wall device comprising:
This device is mainly characterised in that the chassis is provided with means of increasing the intensity of the lighting means.
The main idea of this invention consists in using the chassis itself to increase the light intensity outside the canvas, instead of playing directly on the lighting means parameters as was the case in the prior art.
More specifically, said means of increasing the light intensity consist in a reflective surface suitable for reflecting the incident rays from the lighting means toward the canvas. This invention is thus focused on optical principles, especially on the principle of total reflection, by using the reflecting surface of the chassis. According to the orientation of this surface, its reflective properties, its shape and the direction of the incident light rays from the lighting means, the intensity of the light emitted from the canvas may be increased.
According to various embodiments of this invention, which may be taken together or separately:
This invention also concerns the use of the luminous false-wall device, such as described above, for making light boxes.
The invention will be better understood and other purposes, details, characteristics, and advantages of the invention will appear more clearly on reading the following description given solely by way of an illustrating and non-limiting example and with reference to the accompanying schematic drawings.
In these drawings:
It is to be noted that in the figures, structural and/or functional elements which are common to various embodiments may have identical reference numbers. Thus, unless otherwise indicated, such elements have identical structural and functional properties.
This device contains a chassis 1 constituted by a set of profiles having a complex structure. It is fixed to the vertical walls of a room by screws or any other attachment means.
For example, in order to mount a false-wall on a ceiling, the chassis comprises four profiles extending on the four walls of the room.
A canvas 2 is stretched between these four profiles, at the level of the lower part of the chassis, i.e. the part which is distal to the ceiling. This canvas 2 is provided along its peripheral edges with hook-shaped attachment means 5.
Each profile comprises, in its lower part, a groove 16 with a U-shaped cross-section, defined by two lateral sides 17, 18 and a bottom side 19. The ends of the lateral U-shaped sides, opposed to the bottom side 19, define an aperture for the passage of the hook 5 of the canvas 2 in the groove 16. In order to ensure the hooking of the hook 5 in the groove 16, the internal side of one of the lateral sides has a lip 20 for the longitudinal hooking. In the shown example, the lip 20 is provided on the inner side of the lateral side 17.
Several techniques exist for the hooking of the stretched canvas 2.
Instead of a hook, a beading may be sown on the peripheral edges of the canvas 2. This beading comprises a boss allowing it to be fixed to the lip of the groove.
It is also possible to insert a clip in the groove, the fixing of which still being ensured by the lip. The naked peripheral edges of the canvas 2 are then slid into the clip and retained by pinching.
Other techniques are also encompassed in the scope of the present invention.
In order that the room in which this luminous false-wall device is installed may be lighted, lighting means are provided on the ceiling, and the canvas 2 stretched under the lighting means diffuses the light.
Preferably, this diffusing canvas 2 is translucent, with a light transmission rate of at least 50%. This canvas may be made of textile fabric or PVC, or of any other suitable material.
Another canvas, which will be called “sheet” 3 to avoid any confusion, may optionally be interposed between the lighting means and the canvas 2. This sheet 3 is also diffusing and translucent, with a light transmission rate of at least 50%, in order to let through a maximum of light. This sheet 3 may serve various functions, namely:
This sheet 3 is stretched and fixed to chassis 1 in the same manner as canvas 2, but in another groove 21 located in an upper part of chassis 1, closer to the ceiling. In the example shown, the sheet 3 is provided at its peripheral edges with hooks 6 suitable to be inserted into the groove 21.
This groove 21 has a U-shaped cross-section and is defined by two lateral sides 23, 24 and a bottom side 25.
The hook 6 is retained in the groove 21 by a lip 22 located on the internal side of the lateral wall 23.
In this example, the lateral wall 24 constitutes the upper wall of chassis 1. This wall 24 casts a shadow 7 on the canvas 2 at the vicinity of its peripheral edges. When the canvas 2 is observed from its internal side, a shaded area 7 is seen on the whole perimeter of the canvas 2.
This box comprises a chassis 1 of rectangular shape, also formed by an assembly of four profiles. The profiles have a different shape than those of
In this example, unlike in
In this case, the lower part of chassis 1, directly in contact with the canvas, casts a shadow 7 on all the perimeter of the canvas 2, as it prevents the light rays from lighting means 8 to illuminate the perimeter of the canvas 2 located just beneath the chassis.
In order to avoid this, profiles with triangular cross-sections, as shown in
However, the upper part of the profiles still casts a shadow 7 on the perimeter of the canvas, albeit less obvious than in the case of
On each of
In all cases, these sets of chassis/canvas are adapted to cover a wall of a room, thus being placed vertically, or a ceiling, thus being placed horizontally. The chassis 1 may be fixed directly to ceiling by railings, or indirectly by being suspended, or fixed to the wall by screws as in
With reference to
More specifically, the profile has an upper side 9 directed toward the panel to cover, an external side 10 and an internal side 11 facing the external side 10, the internal side 11 and external side 10 being joined at the tip 14 of the triangle.
The canvas 2 covers this tip 14 and is fixed in the profile at the level of a groove 26, equivalent to the groove 16 in
A groove 27, made on the internal side of the upper part of the profile, is provided to optionally accommodate a protection sheet 3.
The upper side 9 of the profile casts a shadow 7 on the periphery of canvas 2, as explained previously.
The internal side 11 is coated with a reflective layer. In particular, this reflective surface 28 reflects the light emitted by the lighting means 8. In this example, the lighting means is a LED tile, thus a multiple source device.
The reflective layer may be obtained by applying a coat of specific paint on the internal side 11, or by fixing a reflective plate on the internal side 11, or by fixing a mirror on the internal side 11, or by any other means allowing a reflective surface 28 with total reflection to be obtained, i.e. with a reflectance in the order of 100% and a transmittance in the order of 0%.
Some incident rays i1, i2, i3 directly impact the canvas 2, without touching the profile. Then, they are slightly refracted by the canvas 2, forming refracted rays t1, t2, t3. These rays are present in the shaded area 7, whether the profile has a reflective surface 28 or not.
Other incident rays i7, i8, i9 impact the reflective surface 28, and are reflected toward the canvas 2, and more particularly in the direction of the shaded area 7. These reflected rays r7, r8, r9 are then slightly refracted by the canvas 2, and form the rays t7, t8, t9 illuminating the outside of the canvas. In the prior art, these incident rays i7, i8, i9 were stopped or absorbed by the profile and consequently not reflected. The existence of the reflective surface 28 thus allows the quantity of light rays striking the canvas 2 to be increased.
The incident rays i10, i11, i12 also strike the reflective surface 28 at the level of a section 11b of the internal side 11 having a different angle from the section 11a of the internal side 11 where the rays i4 to i9 strike. This section 11b thus reflects the light under a different angle, so forming the reflected rays r10, r11, r12 hitting the canvas 2, then forming the refracted rays t10, t11, t12 leaving the canvas 2. These rays also strike the shaded area 7, whereas they were stopped by the profile in the prior art.
In this example, rays t1, t2, t3, t7, t8, t9, t10, t11, t12 all strike the periphery of the canvas, whereas in the prior art only rays t1, t2, t3 succeeded to do so. This considerable increase of the number of rays reaching the periphery of canvas 2 allows the shaded area 7 to be strongly abated, or even suppressed.
This reflective surface 28 thus allows the distribution of light on the canvas 2 to be homogenized, in order to improve the aesthetic qualities of the device.
On the other hand, this reflective surface 28 also allows the general level of lighting on the canvas 2 to be increased.
Indeed, for example, the incident rays i4, i5, i6 are reflected by the reflective surface 28, forming reflected rays r4, r5, r6 directed on the canvas 2 outside the shaded area, i.e. in the central area of the canvas 2. These rays are then slightly refracted and form the rays t4, t5, t6 on the outside of the canvas 2. These incident rays i4, i5, i6 were stopped by the profile of the prior art, and are now projected on the canvas 2, thus generating a global increase of the lighting power at the output of canvas 2, even outside the shaded area 7.
This is better represented in
However, it is to be noted that the paths of the light rays are purely indicative and that other angles of incidence, reflection and refraction may be obtained by exploiting numerous parameters, such as the orientation of the light sources, the slope of the internal side 11, the reflection properties of the reflective surface 28, the refractive properties of the canvas 2, etc. The addition of a sheet 3 also changes the path of the incident rays.
In particular, the internal side 11 may have various shapes according to the desired result at the output of the canvas.
In
In
In
In
Of course, other shapes may be envisioned, in order to better reflect the rays coming from the light sources 8.
Referring to
The reflective surface 28 may be implemented on all the examples shown in
The intensity of the light coming out of the canvas 2 will be generally increased.
In addition, the light will be distributed homogeneously on the total surface area of canvas 2, even in the shaded area 7, except for the device of
In the examples described, the chassis 1 forms a rectangle with four profiles so as to adopt the conventional rectangular shape of a ceiling, a wall or a box. However, it is possible to envision a chassis having a circular or oval shape, with one or a plurality of appropriately shaped profiles. This invention encompasses all these embodiments.
Concerning the above description, the optimal dimensional relations of the parts of the invention, including any variations in size, materials, shapes, function and modes of working, assembly and use, are considered as apparent and obvious to the person skilled in the art, and all relations equivalent to those shown in the drawings and those detailed in the description are intended to be included in the present invention.
Number | Date | Country | Kind |
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16 56506 | Jul 2016 | FR | national |
Filing Document | Filing Date | Country | Kind |
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PCT/EP2017/064742 | 6/16/2017 | WO | 00 |
Publishing Document | Publishing Date | Country | Kind |
---|---|---|---|
WO2018/007125 | 1/11/2018 | WO | A |
Number | Name | Date | Kind |
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5029422 | Scherrer | Jul 1991 | A |
8054407 | Imojo | Nov 2011 | B2 |
8689505 | Cousin | Apr 2014 | B2 |
8955998 | Wong | Feb 2015 | B2 |
10101002 | Richter | Oct 2018 | B2 |
20160312987 | Danesh | Oct 2016 | A1 |
20190086057 | Kim | Mar 2019 | A1 |
Number | Date | Country |
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10253343 | May 2004 | DE |
2494121 | Sep 2012 | EP |
2722454 | Apr 2014 | EP |
2630476 | Oct 1989 | FR |
2009099465 | May 2009 | JP |
Entry |
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International Search Report dated Aug. 10, 2017 for PCT/EP2017/064742. |
Number | Date | Country | |
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20190242123 A1 | Aug 2019 | US |