FR2998945A1 - ADJUSTABLE COLOR TEMPERATURE LIGHTING DEVICE - Google Patents

Abstract

This device (1) comprises a light source (2) arranged to emit light into a first mixing chamber (4) comprising a leakage orifice (6) and a filtering structure (8) intended to modify the length of the light source. wave of light emitted by the light source (2), giving access to a second mixing chamber (14) for mixing the light output from the first mixing chamber (4) via the filtering structure (8) and via the leakage orifice (6), the lighting device (1) further comprising a closure member (20) for closing at least partially the leakage orifice (6), the orifice (6). leakage device and the closure member (20) being movable relative to each other under the action of a control member allowing a user to control the relative movement of the member (20) shutter with respect to the leakage orifice (6) for calibrating the leakage of light via the leakage orifice (6).

Description

The present invention relates to a lighting device with adjustable color temperature. It is known to produce lighting devices with variable color temperature by using several light sources, each emitting in different color temperatures, and by controlling the extinction and ignition frequency of each of these light sources by the intermediary, for example, a PWM clock. The modification of the switching on and off frequency of each of these light sources makes it possible, taking into account the retinal persistence, to obtain a change in the color temperature perceived by a user. However, these lighting devices require the use of several light sources each emitting light in different color temperatures, which implies a large number of light sources, and an imbalance in the color temperature balance when one or more of these light sources are defective. Also the present invention aims to overcome all or part of these disadvantages by providing an adjustable color temperature lighting device, to vary the color temperature of the light emitted at the output of the lighting device, reliably and reproducible. To this end, the present invention relates to an adjustable color temperature lighting device, characterized in that the lighting device comprises a light source, arranged to emit light in a first mixing chamber, the first mixing chamber comprising a leakage orifice and a filtering structure for modifying the wavelength of the light emitted by the light source, the filtering structure and the leakage orifice giving access to a second mixing chamber, intended to mixing the light output from the first mixing chamber via the filter structure and via the leakage orifice, the lighting device further comprising a closure member for closing at least partially the leakage orifice for allow or prohibit the passage of the light emitted by the light source through the leakage orifice, the leakage orifice and the shutter member being movable one p relative to the other under the action of a control member allowing a user to control the relative movement of the shutter member with respect to the leakage orifice to calibrate the light leaks via the leakage orifice in order to adjust the color temperature of the light emitted at the output of the lighting device.

Thus, the lighting device according to the invention offers the possibility of adjusting the color temperature of the light emitted at the output of the device. This adjustment is obtained by a mechanical solution offering the possibility to the user to generate calibrated leaks of the light emitted by the light source, which may correspond to blue light. These calibrated leaks of blue light are then mixed in the second mixing chamber with the blue light emitted by the light source and having been filtered by the filtering structure (the blue light may correspond to white light after filtration), so that different color temperature lights are mixed in the second mixing chamber (e.g., blue light leaking via the leakage port and white light filtered by the filtering structure). Thus, by controlling the amount of light passing through the leakage orifice by relative displacement of the shutter member and the leakage orifice, the user controls the colorimetry at the output of the device. According to one embodiment, the control member corresponds to a rod movable in rotation with respect to the second mixing chamber, the rod having a proximal end attached to one of the elements selected from the first mixing chamber. shutter member or the filtering structure for pivoting said member about the axis of the rod 20 and thereby relatively relocating the closure member and the leakage orifice relative to each other . Advantageously, the stem further comprises a distal end extending out of the first mixing chamber and out of the second mixing chamber. Thus, the rod can be controlled from outside the second mixing chamber, for example manually by a user, or via an assistance, such as a motor, in particular a stepper motor, controlled remotely. by the user or via a control switch. Advantageously, the device comprises a motor, in particular a stepper motor, connected to the control member to actuate the control member and consequently cause the relative displacement of the shutter member relative to the leakage orifice. According to one embodiment, the second mixing chamber 35 comprises a central sleeve projecting from the bottom of the second mixing chamber, the central sleeve comprising a bore traversed by the rod so that the central sleeve forms a bearing for the rotation of the rod relative to the second mixing chamber. Advantageously, the lighting device comprises means for indicating the relative position of the shutter member with respect to the leakage orifice. According to one possibility, the first mixing chamber is contained in the second mixing chamber, the first mixing chamber and the second mixing chamber being arranged head to tail. Thus, the lighting device according to the invention offers the advantage of compactness. In addition, the light coming out of the first mixing chamber is oriented towards the bottom of the second mixing chamber. Advantageously, the leakage orifice and an opening defined by the first mixing chamber, through which the filtering structure is arranged, are arranged facing the bottom of the second mixing chamber. Thus, the light emerging from the first mixing chamber via the leakage orifice and the one passing through the filtering structure are both reflected against the bottom of the second mixing chamber, which ensures a more efficient mixing. According to one embodiment, the leakage orifice comprises a filtering wall intended to convert the wavelength of the light emitted by the light source into a wavelength distinct from that obtained during the conversion of the length of light. wave of light emitted by the light source by the filtering structure. According to one possibility, the shutter member comprises a shutter superimposed on the filtering structure, the shutter being movable relative to the filtering structure to cover or disengage the leakage orifice, the leakage orifice being formed in the filtering structure. . Advantageously, a side wall of the first mixing chamber comprises a shoulder on which is intended to bear the shutter member, the shoulder being arranged to take the closure member sandwiched with the filtering structure. According to one embodiment, the filtering structure comprises a remote phosphor layer.

By remote phosphor layer means phosphor layer arranged at a distance from the LED chip, as opposed to a layer comprising phosphorus deposited directly on the LED chip.

Other characteristics and advantages of the present invention will emerge clearly from the following description of a particular embodiment, given by way of non-limiting example, with reference to the appended drawings in which: FIG. 1 is a view in perspective of a lighting device according to one embodiment of the invention, - Figure 2 is a sectional and side view of a lighting device according to one embodiment of the invention, - the FIGS. 3 to 5 are top and perspective views of various elements of a lighting device according to one embodiment of the invention; FIGS. 6 to 8 are sectional and side views of a device; according to one embodiment of the invention, in different operating positions, - Figures 9 to 11 are sectional and side views of a lighting device according to another embodiment of the invention. , in different positions of FIGS. 12 and 13 are perspective views of a portion of the illumination device of FIGS. 9 to 11, FIGS. 14 and 15 are top views of a portion of a lighting device. according to another embodiment, in different operating positions. FIG. 1 shows an adjustable color temperature lighting device 1 according to one embodiment of the invention.

As can be seen in FIGS. 1 and 2, the lighting device 1 comprises a light source 2, arranged to emit light in a first mixing chamber 4. As can be seen in FIGS. 2 and 3, the first mixing chamber 4 comprises a leakage orifice 6 and a filtering structure 8 intended to modify the wavelength of the light emitted by the light source 2.

The first mixing chamber 4 comprises for example a bottom 10 from which extends a side wall 12. The first mixing chamber 4, in particular the lateral wall 12, advantageously delimits an opening through which the filtering structure 8 is arranged. The opening 5 opens advantageously inside a second mixing chamber 14. The second mixing chamber 14 comprises for example a bottom 16 from which extends a side wall 18. The second mixing chamber 14, in particular the side wall 18, defines an outlet opening for the mixed light in this second mixing chamber 14, as can be seen for example in FIG. 1. The filtering structure 8 and the orifice 6 of leakage give access to the second mixing chamber 14, for mixing the light output of the first mixing chamber 4, via the filtering structure 8 on the one hand and via the leakage port 6 on the other hand. As shown in Figures 1 and 2, the first mixing chamber 4 may be integrally contained in the second mixing chamber 14. Advantageously, the first mixing chamber 4 and the second mixing chamber 14 can be arranged head to tail. In other words, the leakage orifice 6 and the opening defined by the first mixing chamber 4 across which the filtering structure 8 is arranged can be arranged facing the bottom 16 of the second mixing chamber 14. The lighting device 1 also comprises a closure member 25, shown in FIG. 4, for closing at least partially the leakage orifice 6, that is to say to allow or prohibit the passage of light. emitted by the light source 2 through the leakage orifice 6. The leakage orifice 6 and the closure member 20 are movable relative to each other, for example between a first position, shown in FIGS. 8, 9 and 14, in which the member 20 shutter completely closes the leakage orifice 6 to prevent the light emitted by the light source 2 from passing through the leakage orifice 6 (the light emitted by the light source 2 is constrained in this case to pass in totality through the filtering structure 8), and a second position, shown in FIGS. 6 and 11, in which the closure member 20 completely clears the passageway through the leakage orifice 6. Figures 7, 10 and 15 show an intermediate position between the first position and the second position, the shutter member 20 partially closing the leakage orifice 6 by releasing a partial passage for the light emitted by the source 2 light . The relative displacement of the closure member 20 and the leakage orifice 6 is achieved by means of a control member, which can correspond to a rod 22, rotatable relative to the second mixing chamber 14 . The rod 22 may have a proximal end 24 attached to one of the elements selected from the first mixing chamber 4, the closure member 20 or the filtering structure 8. More particularly, it will be noted that the rod 22 may be integral with the closure member 20, which it rotates while the element on which the leakage orifice 6 is formed (for example the first chamber 4 of FIG. mixing, or the filtering structure 8 as in the examples shown) remains stationary relative to the second mixing chamber 14. The rod 22 may alternatively be secured to the element on which the leakage orifice 6 (for example the first mixing chamber 4, or the filtering structure 8 according to the examples shown) is formed, and in fact cause this element and the 6 orifice leakage in rotation, while the shutter member 20 remains stationary relative to the second chamber 14 mixing. According to the example of FIGS. 1 to 8, the proximal end 24 of the rod 22 is integral with the first mixing chamber 4, so that the first mixing chamber 4 and all the elements which are integral therewith, 25 for example the closure member 20 are rotatable relative to the second mixing chamber 14. According to this example, the leakage orifice 6 is provided on the filtering structure 8, mounted motionless relative to the second mixing chamber 14. The rod 22 further comprises a distal end 26 extending out of the first mixing chamber 4 and out of the second mixing chamber 14. The lighting device 1 may comprise means for indicating the relative position of the closure member 20 with respect to the leakage orifice 6, comprising, for example, notches 27 or marks on the second mixing chamber 14 and a lug 29 integral with the rod 22, arranged to face one of the notches 27 or marks when the closure member 20 and the leakage orifice 6 are in a predetermined relative position. As can be seen in FIGS. 3 and 4, the filtering structure 8 and the closure member 20 may have a disc shape, of different diameters (that of the closure member 20 is smaller than that of the filtering structure 8), intended to be arranged concentrically. The closure member 20 and the filtering structure 8 may each have a central bore 31, 33, for the passage of the rod 22. As can be seen for example in FIG. 2, the second mixing chamber 14 comprises a sleeve 28 central projecting from the bottom 16 of the second chamber 14 mixing. The central sleeve 28 may comprise a bore 30 through which the rod 22 passes; the central sleeve 28 thus forms a bearing for the rotation of the rod 22 relative to the second mixing chamber 14.

The central sleeve 28 may comprise an upper support surface 32 allowing the assembly formed by the first mixing chamber 4, the filtering structure 8 and the closure member 20 to rest on the central sleeve 28. Thus, the first mixing chamber 4 is held in position inside the second mixing chamber 14 via the central sleeve 28. As can be seen in FIGS. 9 to 11, the first mixing chamber 4, the closure member 20 or the filtering structure 8 may comprise a sleeve 34 designed to cooperate in complementary form with the central sleeve 28 of the second mixing chamber 14. This arrangement offers the advantage of greater stability and greater robustness of the lighting device 1. The leakage orifice 6 may comprise a filtering wall, shown diagrammatically in FIG. 3 for one of the three leakage orifices 6, intended to convert the wavelength of the light emitted by the light source 2 into a length wave different from that obtained during the conversion of the wavelength of the light emitted by the light source 2 by the filtering structure 8. As illustrated in FIG. 3, the filtering structure 8 comprises, for example, a layer 36 comprising a filtering material. The layer 36 may be supported by a support portion 38 defining an opening in which the layer 36 comprising the filter material extends.

As can be seen in FIG. 1, the lateral wall 12 of the first mixing chamber 4 may comprise a shoulder 40 on which the support portion 38 of the filtering structure 8 is to bear. As illustrated in FIG. 4, the closure member 20 may comprise a flap 42 superimposed on the filtering structure 8, the flap 42 being movable relative to the filtering structure 8 to cover or disengage the leakage orifice 6 , the leakage orifice 6 being here formed in the filtering structure 8. The side wall 12 of the first mixing chamber 4 may comprise a shoulder 44 on which the closure member 10 is intended to bear, the shoulder 44 being arranged to take the closure member 20 in sandwich with the filtering structure 8. The closure member 20 can be secured to the first mixing chamber 4, for example by being glued to the shoulder 44. The filtering structure 8 can in turn be secured to the second mixing chamber 14, by example being glued or force-fitted on the sleeve 28 of the second central chamber 14 of mixing. The leakage orifice 6 may be formed in the filtering structure 8 as shown in FIGS. 1 to 15, in particular in the support portion 38 of the filtering structure 8, or possibly in one of the walls of the first mixing chamber 4 among the side wall 12 or the bottom 10 of the first mixing chamber 4. According to the example of FIGS. 9 to 13, the leakage orifice 6 may be arranged on an outside diameter of the filtering structure 8. According to the example of FIGS. 14 and 15, the leakage orifice 6 may be provided on an inside diameter of the filtering structure 8. As shown in Figure 2, the second mixing chamber 14 may include a diffuser 48 arranged to at least partially cover the outlet opening. The diffuser 48 can be supported on a shoulder 46 formed on the side wall 18 of the second mixing chamber 14. The outlet opening may also include a layer comprising a filter material. This layer of filtering material may thus comprise phosphorus, for example making it possible to modify the color temperature of the light mixed in the second mixing chamber in a color temperature range which may be between 7000 ° K. and 9000 ° K. in particular of the order of 8000 ° K.

The light source 2 can be arranged at the bottom 10 of the first mixing chamber 4 to emit light towards the opening delimited by the lateral wall 12 of the first mixing chamber 4, thus towards the bottom 16 of the second chamber 14 mixing.

The light source 2 may correspond to a light emitting diode (LED according to the acronym). It can emit blue light of wavelength for example between 400 nm and 550 nm. The color temperature of the light emitted by the light source may be greater than 5500 ° K, for example between 6000 ° K and 7000 ° K.

The filtering structure 8 may comprise phosphorus. Thus, the filter material of the layer 36 may correspond to phosphorus. The phosphor of the filtering structure 8 may, for example, make it possible to convert the light emitted by the light source into white light, whose color temperature may be between 1000 ° K and 4000 ° K, in particular between 2000 ° K and 3000 ° K. . Similarly, when present, the filter wall arranged across the leakage port 6 may comprise phosphor, for converting the light emitted by the light source 2 into a color temperature distinct from that of the light. emitted by the light source 2, and which also differs from the color temperature of the light filtered by the filtering structure 8, to maintain a mixing of two different color temperatures in the second mixing chamber 14. In operation, it suffices for the user to rotate the rod 22 to move the closure member 20 relative to the leakage orifice 6, which has the effect of calibrating the light leak emitted by the light source 2 through the first mixing chamber 4. Thus, the user can control the proportion of light emitted by the light source 2 which is intended to pass through the leakage orifice 6. Since this light is mixed with the light filtered by the filtering structure 8, which is of a different color temperature, the user, by controlling the quantity of light leaking via the leakage orifice 6, thus controls the colorimetry of the light. at the output of the device 1. Of course, the invention is not limited to the embodiment described above, this embodiment having been given by way of example. Modifications are possible, in particular from the point of view of the constitution of the various elements or by the substitution of technical equivalents, without departing from the scope of the invention.

Thus, the closure member 20 may for example correspond to a diaphragm.

Claims (12)

REVENDICATIONS1. Adjustable color temperature illumination device (1), characterized in that the illumination device (1) comprises a light source (2) arranged to emit light into a first mixing chamber (4). first mixing chamber (4) comprising a leakage orifice (6), and a filtering structure (8) intended to modify the wavelength of the light emitted by the light source (2), the filtering structure (8) and the leakage orifice (6) giving access to a second mixing chamber (14) for mixing the light output from the first mixing chamber (4) via the filtering structure (8) and via the orifice (6) ), the lighting device (1) further comprising a closure member (20) for closing at least partially the leakage orifice (6) to allow or prohibit the passage of the light emitted by the source (2) illuminated through the leakage orifice (6), the leakage orifice (6) and the closure member (20) ation being movable relative to one another under the action of a control member allowing a user to control the relative movement of the closure member (20) with respect to the orifice (6) leakage device for calibrating light leakage via the leakage orifice (6) to adjust the color temperature of the light emitted at the output of the lighting device (1). 2. Device (1) for lighting according to claim 1, characterized in that the control member corresponds to a rod (22) rotatable relative to the second chamber (14) mixing, the rod (22). having a proximal end (24) attached to one of the selected ones of the first mixing chamber (4), the closure member (20) or the filtering structure (8) to rotate said member around the axis of the rod (22) and thus move relatively relative to each other the closure member (20) and the orifice (6) of leakage. 3. Device (1) for lighting according to claim 2, characterized in that the rod (22) further comprises a distal end (26) extending out of the first mixing chamber (4) and out of the second mixing chamber (14) .35 4. Device (1) for lighting according to claim 2 or 3, characterized in that the second mixing chamber (14) comprises a sleeve (28) central projecting from the bottom (16) of the second chamber (14), the central sleeve (28) comprising a bore (30) through which the rod (22) passes so that the central sleeve (28) forms a bearing for the rotation of the rod (22) relative to the second chamber (14) mixing. 5. Lighting device (1) according to one of claims 1 to 4, characterized in that the lighting device (1) comprises means for indicating the relative position of the closure member (20). relative to the leakage orifice (6). 6. Lighting device (1) according to one of claims 1 to 5, characterized in that the first mixing chamber (4) is contained in the second mixing chamber (14), the first chamber (4) mixer and the second mixing chamber (14) being arranged upside down. 7. Device (1) for lighting according to one of claims 1 to 6, characterized in that the orifice (6) of leakage and an opening defined by the first chamber (4) mixing, across which is arranged the filtering structure (8), are arranged facing the bottom (16) of the second chamber (14) mixing. 8. Lighting device (1) according to one of claims 1 to 7, characterized in that the leakage orifice (6) comprises a filter wall (35) intended to convert the wavelength of the light. emitted by the light source (2) at a wavelength distinct from that obtained during the conversion of the wavelength of the light emitted by the light source (2) by the filtering structure (8). 30 9. Device (1) for lighting according to one of claims 1 to 8, characterized in that the member (20) shutter comprises a flap (42) superimposed on the structure (8) filtering, the flap ( 42) being movable relative to the filtering structure (8) to cover or disengage the leakage orifice (6), the leakage orifice (6) being formed in the filtering structure (8). 10. Device (1) for lighting according to one of claims 1 to 9, characterized in that a wall (12) side of the first mixing chamber (4) comprises a shoulder (44) on which is intended to support the closure member (20), the shoulder (44) being arranged to take the closure member (20) sandwiched with the filter structure (8). 11. Device (1) for lighting according to one of claims 1 to 10, characterized in that the structure (8) filter comprises a layer (36) of remote phosphor. 12. Device (1) for lighting according to one of claims 1 to 11, characterized in that the device (1) comprises a motor, in particular a stepper motor, connected to the control member for actuating the control member and consequently causing the relative displacement of the closure member (20) with respect to the leakage orifice (6).