OPERATING SAID LIGHT FIXTURE"

Cross-Reference to Related Applications

This Patent Application claims priority from Italian Patent Application No . 102022000001925 filed on February 3 , 2022 , the entire disclosure of which is incorporated herein by reference .

Technical Field

The present invention relates to a light fixture for producing scenic effects and to a method for operating said light fixture .

Background

The light fixtures of the type identi fied above are used in the entertainment sector for creating scenic ef fects by means of plays of light .

In such sector, the research for new ef fects and plays of light is constant . Over the last years , in particular, most of the efforts have been concentrated on the creation of new scenic ef fects by means of the use of high power light beams .

However, generating high power light beams requires suitable cooling systems .

Suitable cooling systems can however increase the overall bulk of the light fixture and/or have di f ficulty in integrating in a structure , already complex in itsel f and comprising one or more beam processing elements . Summary

Therefore , an obj ect of the present invention i s to manufacture a light fixture of the type identi fied above , capable of generating innovative scenic ef fects by means of the use of high power light beams and which is exempt from the drawbacks of the prior art .

In accordance with such obj ects , the present invention relates to a light fixture extending along a longitudinal axis and configured to produce scenic ef fects ; the light fixture comprising :

- a frame ;

- at least one main reflector, which is supported by the frame and has a concave and at least partly reflective surface ;

- a source assembly supported by the frame and configured to generate at least one light beam to illuminate the surface of the main reflector ; the source assembly comprising at least one first linear light source arranged outside the inner volume o f the main reflector ; the light fixture being configured so that the relative distance between the main reflector and the at least one linear light source is variable .

A further obj ect of the present invention is to provide a method for operating said light fixture .

In accordance with such obj ects , the present invention relates to a method for operating a light fixture as claimed in claim 19 .

Brief Description of the Drawings

Further characteristics and advantages of the present invention will be clear from the following description of a non-limiting example embodiment thereof , with re ference to the figures of the accompanying drawings , wherein :

- Figure 1 is a perspective view of the light fixture according to the present invention;

- Figure 2 is a section view along plane I I of the light fixture of Figure 1 in a first operating position;

- Figure 3 is a section view along plane I I of the light fixture of Figure 1 in a second operating position;

- Figure 4 is a section view along plane I I of the light fixture of Figure 1 in a third operating position;

- Figure 5 is a section view, with parts removed for clarity, of a detail of Figure 4 ;

- Figure 6 is a schematic perspective view, with parts removed for clarity, of a detail of the light f ixture of Figure 1 in a first operating configuration;

- Figure 7 is a schematic perspective view, with parts removed for clarity, of a detail of the light f ixture of Figure 1 in a second operating configuration;

- Figure 8 is a top schematic view, with parts removed for clarity, of a detail of Figure 6 ;

- Figure 9 is a top schematic view, with parts removed for clarity, of the detail of Figure 6 in accordance with an alternative embodiment ; - Figure 10 is a schematic representation of the optical path of the light radiations in the light fixture according to the present invention .

Description of Embodiments

In Figure 1 , reference numeral 1 indicates a light fixture .

The light fixture 1 is preferably used, alone or in combination with other light fixtures ( identical or also of di f ferent type ) , within the entertainment field for generating light ef fects and plays of light .

The light fixture 1 extends along a longitudinal axis A and comprises a frame 2 , at least one main reflector 3 (better visible in Figures 2 -4 ) supported by the frame 2 and comprising a concave and at least partly reflective surface 4 , at least one source assembly 6 supported by the frame 2 and comprising at least one linear light source 7 (visible in Figure 2 ) and arranged externally to the inner volume defined by the main reflector 3 and towards which the surface 4 is faced .

In particular, as it will be speci fically evident in the following, the light fixture 1 is configured such that the relative distance between the main reflector 3 and the at least one linear light source 7 is variable . In other words , one of the main reflector 3 and the at least one linear light source 7 is movable .

With reference to Figure 1 and to Figure 2 , the frame 2 is configured to define a main chamber 8 , provided with an inner base 9 and with at least one side wall 10 which surrounds the inner base 9 . Preferably, the frame 2 is configured to also define a bottom chamber 12 provided with an outer base 13 and with at least one side wall 14 which surrounds the outer base 13 .

Preferably, the inner base 9 and the outer base 13 have a quadrangular shape and are surrounded by four side walls 10 and 14 , respectively .

The bottom chamber 12 is closed at the top by the inner base 9 . In other words , the inner base 9 defines the roof of the bottom chamber 12 .

As it will be speci fically evident in the following, the inner base 9 is provided with two openings 15 ( only one of which is visible in Figure 2 ) .

Preferably, two opposite walls 10b of the four side walls 10 of the main chamber 8 are made in one piece with respective two opposite walls 14b of the four side walls of the bottom chamber 12 ( see also Figure 1 in which the walls 14a and 14b are visible externally) , the other opposite walls 10a are preferably separated from the remaining opposite walls 14a .

Preferably, the walls 10a are arranged parallel to the longitudinal axis A, whereas the walls 10b are arranged orthogonal to the longitudinal axis A.

More preferably, the side walls 10b extend beyond the side walls 10a for providing support to possible further elements of the l ight fixture 1 ( as it will be speci fically evident in the following) .

With reference to Figure 2 , the main reflector 3 , preferably movable , is arranged in the main chamber 8 . In the bottom chamber 12 a moving device 16 is at least partly housed, configured to move the main reflector 3 , as it will be speci fically evident in the following .

The separation into a main chamber 8 and a bottom chamber 12 allows selectively intervening on the elements housed in one of the chambers without running the risk of accidentally damaging the elements contained in the other chamber of the two chambers .

A variation not illustrated provides for the frame to define one single chamber .

With reference to Figures 2 , 3 and 4 , the main reflector 3 comprises a wall 17 provided with the surface 4 .

Preferably, the wall 17 extends along a direction parallel to the longitudinal axis A and is shaped such that the surface 4 is , as already mentioned, concave .

Preferably, the wall 17 is shaped such that the surface 4 is a portion of a cylindrical surface .

Advantageously, a curvature having a cylindrical symmetry determines an exiting elongated beam .

The surface 4 can be completely reflective ( for example completely shiny) or can comprise reflective parts and non-ref lect ive parts ( for example textured or facetted) . Further variations provide for the surface 4 to be anisotropically reflective so as to proj ect a speci fic configuration .

As mentioned, the main reflector 3 is housed in the main chamber 8 and is movable along a direction C orthogonal to the longitudinal axis A between a collimated beam position, al so called NARROW ( illustrated in Figure 3 ) and a divergent beam position, also cal led WIDE ( illustrated in Figure 4 ) . In the collimated beam position the main reflector 3 is arranged distal to the at least one linear light source 7 , whereas in the divergent beam position the main reflector 3 is arranged proximal to the at least one linear light source 7 .

Therefore , in the collimated beam position, the distance between the main reflector 3 and the linear light source 7 is maximum, whereas in the divergent beam position, the distance between the main reflector 3 and the linear beam source 7 is minimum .

In Figure 2 , the main reflector 3 is arranged in an intermediate position between the divergent beam position and the collimated beam position .

As it will be evident in the following, the movement of the main reflector 3 determines a variation of the opening of the light beam emitted by the light fixture 1 .

As already mentioned, the main reflector 3 is moved by a moving device 16 , which is preferably at least partly housed in the bottom chamber 12 .

The operation of the moving device 16 is preferably adj usted by a control device (not visible in the accompanying figures ) . The control device can also be managed remotely, preferably by means of communications with DMX protocol .

According to a variation not illustrated, the operation of the moving device is manual .

With reference to Figure 2 , in the non-limiting example described and illustrated herein, the moving device 16 comprises an articulated transmission system 19 , a support plate 20 coupled to the main reflector 3 and an actuator device 21 .

Here and in the following, the definition "articulated transmission system" means a transmission system de fined by a plurality of bodies , preferably levers or bars , mutually bound by means of spherical or cylindrical hinges .

With reference to Figure 6, the articulated transmission system 19 comprises two pairs of levers 24 articulated to each other .

The pairs of levers 24 are arranged spaced apart from each other and are coupled to respective portions of the reflector 3 .

Each lever 24 is provided with an end 27 coupled to the support plate 20 in a rotatable manner, and with an end 28 coupled to the actuator device 21 in a rotatable manner .

With reference to Figure 6 and to Figure 7 , preferably the levers 24 are articulated to each other by means of a pin 25 . More preferably, the pin 25 is a pivot pin provided with a bearing ( not visible in the accompanying figures ) , which engages a circular hole 29 of one lever 24 and a shaped eyelet 30 of the other lever 24 . The eyelet 30 is shaped so as to guide the movement of the pin 25 during the relative movement of the levers 24 for li fting and lowering the support plate 20 ( and thus the main reflector 3 coupled thereto ) .

The eyelet 30 is shaped so as to contain the pin 25 for binding the levers 24 together, ensuring the perpendicularity of the reflector 3 with respect to the direction C during the movement between the WIDE and NARROW positions .

The actuator device 21 comprises two carriages 31 , at least one guide 32 , at least one motor 33 for moving the carriages 31 and a transmission device 34 configured to transmit motion from the motor 33 to the carriages 31 .

The guide 32 and the motor 33 are fixed to the frame 2 . In the speci fic example described and illustrated herein, the guide 32 and the motor 33 are fixed to the inner base 9 .

One lever 24 of each pair of levers 24 has the end 28 coupled to a carriage 31 , the other lever 24 of the pair has the end 28 coupled to the other carriage 31 .

The carriages 31 are slidable along the guide 32 between a first position in which the carriages 31 are arranged distal to each other ( Figure 7 ) and a second position in which the carriages 31 are arranged proximal to each other ( Figure 6 and Figure 8 ) .

In other words , the movement of the carriages 31 is a mutual moving away movement in the passage from the second position to the first position and a mutual approaching movement in the passage from the first position to the second position .

During the moving away of the carriages 31 , the support plate 20 coupled to the main reflector 3 lowers approaching the reflector 3 to the collimated beam position (NARROW - Figure 3 ) , whereas during the approaching of the carriages 31 , the support plate 20 li fts approaching the main reflector 3 to the divergent beam position (WIDE - Figure 4 ) .

Preferably, the guide 32 along which the carriages 31 slide , extends along a direction substantially parallel to the longitudinal axis A.

Preferably, the guide 32 is defined by at least one support element 35 , which slidably engages respective through-holes 36 of the carriages 31 .

In the non-limiting example described and illustrated herein, the guide 32 comprises two support elements 35 , arranged parallel , which slidably engage respective holes 36 of the carriages 31 .

In other words , the support elements 35 define a track on which the carriages 31 slide .

The motor 33 is an electric motor, preferably of the stepper type .

The transmission device 34 is configured to transmit motion from the motor 33 to the carriages 31 and comprises at least one screw 40 moved, directly or indirectly, by the shaft of the motor 33 and coupled to the carriages 31 .

In the non-limiting example described and illustrated herein, the transmission device 34 comprises two threaded screws 40a 40b having the same thread direction ( see also Figure 8 ) .

The screw 40a engages respective through-holes 42a of the carriages 31 . The through-holes 42a are aligned with each other .

The screw 40b engages respective through-holes 42b of the carriages 31 . The through-holes 42b are aligned with each other .

Preferably, both screws 40a 40b are arranged between the support elements 35 of the guide 32 .

At least one of the through-holes 42a of one carriage 31 is provided with a nut screw 43a ( inside the carriage and not completely visible in the accompanying figures ) configured to mesh with the screw 40a .

At least one of the through-holes 42b of the other carriage 31 is provided with a nut screw 43b ( inside the carriage and not completely visible in the accompanying figures ) configured to mesh with the screw 40b .

With reference to Figure 6 and to Figure 8 , the screws 40a 40b are provided with respective ends 44a 44b, which are coupled to each other by means of respective gear wheels 45a 45b .

The coupling by means of the gear wheels 45a 45b allows the transmission of the rotation movement from one screw to the other . In particular , the rotation movement of the screws is opposite .

In other words , it is suf ficient to move in the necessary direction only one screw of the two screws 40a 40b in order to obtain the movement of the other screw 40b 40a in the opposite direction .

The movement of the screws 40a 40b determines the movement of the carriages 31 as is clearly illustrated in Figure 8 .

Preferably, the transmission device 34 further comprises a belt 46 , which transmits the motion of the shaft 47 of the motor 33 to one of the screws 40a 40b .

In particular, the belt 46 connects the shaft 47 with the screw which is closer to the shaft 47 ( in the nonlimiting example described and illustrated herein it corresponds to the screw 40b ) .

Therefore , in use , the rotation of the shaft 47 of the motor 33 determines a rotation in the same direction of the screw 40b and a consequent rotation, in oppos ite direction, of the screw 40a as is illustrated in Figure 8 .

With reference to Figure 2 , as already partly mentioned, the moving device 16 is preferably at least partly housed in the bottom chamber 12 . In particular, the actuator device 21 is housed in the bottom chamber 12 of the frame 2 , the pairs of levers 24 pass through the openings 15 of the inner base 9 and the support plate 20 coupled to the main reflector 3 is arranged in the main chamber 8 .

In particular, the motor 33 is fixed to the inner base 9 along the surface which faces the bottom chamber 12 and the support elements 35 of the guide 32 are coupled to supports 39 which are also fixed to the surface of the inner base 9 which faces the bottom chamber 12 .

Figure 9 schematically illustrates a variation of the transmission device 34 , which comprises one single screw 40 , which is divided into a portion 48a with a thread direction and a portion 48b with an opposite thread direction .

The carriages 31 are provided with holes 42 for the passing of the screw 40 and are both provided with nut screw (not illustrated) configured to mesh with the respective threaded portion of the screw 40 .

In this embodiment it is thus suf ficient to move the sole screw 40 in a direction or in the opposite direction for obtaining the approaching or the moving away of the carriages 31 .

The screw 40 can be moved directly or indirectly ( for example by means of belt not illustrated) .

With reference to Figure 2 , the source assembly 6 is supported by the frame 2 and comprises at least one linear light source 7 and is arranged externally to the inner volume defined by the main reflector 3 and towards which the surface 4 is faced .

The linear light source 7 is preferably coupled to the side wall 10 which surrounds the inner base 9 of the main chamber 8 of the frame 2 .

In the non-limiting example described and illustrated herein, in which the frame 2 comprises four side walls 10 , it comprises two linear light sources 7 arranged on opposite walls 10a of the frame 2 . The linear light sources 7 are both external to the inner volume defined by the main reflector 3 .

In particular, the linear light sources 7 are fixed to the opposite walls 10a along the inner surface 50 which faces the main chamber 8 .

In this manner, the linear light sources 7 face the main chamber 8 in which the main reflector 3 is arranged .

Preferably, the linear light sources 7 are rectilinear and extend along a respective longitudinal axis Bl , B2 parallel to the longitudinal axis A.

More preferably, the linear light sources 7 extend along the entire axial length of the respective wal l 10a to which they are coupled .

In the non-limiting example described and illustrated herein, the linear light sources 7 are substantially identical .

Preferably, each linear light source 7 comprises a plurality of light elements 51 aligned along the direction of extension of the linear light source . Preferably, the light elements 51 are arranged equally distant from each other .

In accordance with a variation not illustrated, the light elements are arranged at irregular distances and/or are not all aligned . Each light element 51 is preferably configured to generate light radiations of di fferent colour .

Each light element 51 is controllable in an independent manner by a control device (not illustrated) . The control can be carried out also remotely .

For example , the control can provide for the activation/ turning of f of the high frequency light elements 51 so as to obtain stroboscopic ef fects or a variation of the colours and of the intensities of the light elements 51 .

In the non-limiting example described and illustrated herein, each light element 51 comprises four LEDs of the RGBW (Red Green Blue White ) type . A variation not illustrated provides for arranging light elements comprising single LEDs having di f ferent emission spectrum . In other words , the LEDs having di f ferent emission spectrum are next to each other so as to form the linear light source .

For example , the light source can comprise light elements with single LEDs in sequence according to the following pattern R-G-B-W-R-G-B-W-R-G-B-W ....

In accordance with a further variation not illustrated, the LEDs can be arranged on at least two parallel rows .

The source assembly 6 further comprises a cooling device 52 , which is arranged in the proximity of the linear light source 7 and is configured to dissipate the heat generated by the linear light source 7 .

In the non-limiting example described and illustrated herein, the cooling device 52 is a passive cooling device and comprises two f inned dissipating elements 53 (normally defined heat sinks ) , which are fixed along the outer surface of the walls 10a of the frame 2 which support the linear light sources 7 .

Substantially, the walls 10a of the frame 2 support on one side the linear light source 7 and on the opposite side a respective dissipating element 53 .

The structure of the light fixture 1 thus allows having linear light sources 7 suf ficiently close to the respective dissipating element 53 . This allows using high power linear light sources 7 without running risks of overheating .

In particular, each dissipating element 53 is defined by a base 54 , from which a plurality of cooling fins 56 protrude , preferably parallel to each other . The base 54 is coupled to the wall 10a of the frame 2 .

The cooling fins 56 are also preferably parallel to the longitudinal axis A. The cooling device 52 is preferably made of die-cast or extruded metal .

In accordance with a variation not illustrated, the cooling device is of active type and comprises air cooling fans or diaphragms .

Preferably, the dissipating elements 53 are fixed to the walls 10b of the frame 2 , in addition to the side walls 10a, as is illustrated in Figure 1 .

Preferably, the dissipating elements 53 have an axial length (understood as the length measured along the axis A) equal to at least the axial length of the linear light source 7 which they have to cool .

In the non-limiting example described and illustrated herein, the source assembly 6 comprises at least one light guide 60 associated with the at least one linear light source 7 .

In particular, the light guide 60 is coupled to the at least one linear light source 7 so as to collect the light beam emitted by the linear light source 7 and define a determined optical path .

In the speci fic example described and illustrated herein, wherein the linear light sources 7 are two , the source assembly 6 comprises two light guides 60 , each of which is associated with a respective linear light source 7 .

In accordance with a variation not illustrated, the source assembly comprises one single light guide , configured to collect the light beams from one or more linear light sources and define , for the collected beams , a determined optical path .

Preferably, the light guides 60 are substantially identical and are planar .

In the non-limiting example described and illustrated herein, the light guides 60 extend along a respective plane . Preferably, the light guides 60 extend along a same plane Z substantially orthogonal to the direction C and are configured to substantially close the main chamber 8 .

In the non-limiting example described and illustrated herein, the plane Z is arranged along the focal line of the main reflector 3 when the reflector is in the NARROW position . In other words , the plane Z is arranged along the focal line of the main reflector 3 when the reflector 3 is arranged distal to the at least one linear light source 7 , i . e . when the distance between the reflector 3 and the at least one linear light source 7 is maximum .

Focal line means the line containing the focal points identi fied by each section of the reflector 3 along a plane orthogonal to the longitudinal axis A.

In particular, each light guide 60 is defined by a plate having a determined thickness (measured orthogonally to the plane on which the light guide extends ) , which is provided with an edge 62 , with an inner wall 63 (which faces , in use , the main reflector 3 ) and an outer wall 64 (which faces , in use , the zone external to the light fixture 1 ) .

In the non-limiting example described and illustrated herein, the edge 62 has a quadrangular shape and is supported, preferably on at least two sides (preferably three ) , by the frame 2 .

Preferably, the frame 2 has along the walls 10a and 10b grooves 65a 65b suf ficiently deep for allowing the housing of a portion of the edge 62 suf ficient to ensure a stable support of the light guide 60 .

In the grooves 65a along the walls 10a also the linear light sources 7 are preferably housed .

In this manner, the linear light sources 7 are not visible from the outside .

In the non-limiting example described and illustrated herein, the light guide 60 is provided, along the edge 62 , with at least one input side 67 , which faces the respective linear light source 7 , and at least one output side 68 , which is arranged on an opposite side with respect to the input side 67 .

Between the input side 67 and the output side 68 , the edge 62 comprises two resting sides 69 , which engage the grooves 65b of the walls 10b of the frame 2 .

In the non-limiting example described and illustrated herein, the inner wall 63 and the outer wall 64 are arranged parallel . In accordance with a variation, the inner wall and the outer wall can be inclined with a divergence towards the output side 68 . Preferably, the input side 67 is arranged at a distance with respect to the respective linear light source 7 less than a threshold value so as to collect most of the light radiations emitted by the linear light source 7 .

In the non-limiting example described and illustrated herein, the input side 67 extends orthogonal to the inner wall 63 and to the outer wall 64 .

With reference also to Figure 5 , the output side 68 is preferably inclined with respect to the inner wall 63 and to the outer wall 64 .

Preferably, the output side 68 forms an acute angle with the inner wall 63 .

It is understood that the inclination of the output side 68 can be suitably adj usted so as to optimi ze the redirecting of the light radiations towards the main reflector 3 .

In the non-limiting example described and illustrated herein, the output side 68 is coupled to a further reflector 70 .

The further reflector 70 , in particular, is provided with two reflective sides 71 inclined and convergent to one another so as to form between each other an angle a . Each reflective side 71 faces a respective output side 68 of the light guide 60 .

In the non-limiting example described and illustrated herein, the reflective side 71 is arranged in contact with the output side 68 of the light guide 60 and substantially has the same inclination of the respective output side 68 .

The further reflector 70 is arranged along the plane Z and extends along a direction parallel to the longitudinal axis A.

Preferably, the further reflector 70 is supported by the frame 2 . In particular, the further reflector 70 extends from one side wall 10b to the other and is fixed to the side walls 10b .

In other words , the further reflector 70 is arranged between the light guides 60 in contact with the output sides 68 of the light guides 60 .

Each light guide 60 is configured such that the inner wall 63 and the outer wall 64 are transparent to radiations coming from the main reflector 3 and are reflective , by total internal reflection ( TIR) , for light radiations entering through the input side 67 and exiting through the output side 68 , as is illustrated in Figure 10 .

The light guides 60 are thus made of a transparent material . For example , the light guides 60 are made of glass .

According to a variation not illustrated, on the output side a layer of reflective material is arranged, for example isotropic reflective silver aluminium .

In this manner, it is possible to prevent the use of the further reflector .

The source assembly 6 preferably also comprises a di f fuser element 77 ( represented by a dashed line in Figures 3 and 4) , which is arranged at the output of the further reflector 70.

In the non-limiting example described and illustrated herein, the diffuser element 77 comprises a plano-convex longitudinal lens.

The plano-convex longitudinal lens, when present, contributes towards making the light radiation exiting the light guide 60 converge towards the reflector 3, increasing the overall optical efficiency.

In accordance with a variation, the diffuser element can comprise a layer of diffusive material coupled to the inner walls 63 of the light guides 60 or can comprise a diffuser body to which also a lens is coupled.

In accordance with further variations not illustrated, the diffuser element can have a different diffusive structure depending on the needs (isotropic, elliptical, prismatic, etc.)

With reference to Figure 10, in use, the light radiations emitted by the linear light sources 7 are guided through the respective light guides 60 towards the further reflector 70, which reflects them towards the main reflector 3.

The light rays which strike the main reflector 3 pass through the light guides 60 and are projected towards the outside of the light fixture 1 originating a light beam.

Optionally, at the output of the reflector 70, the diffuser element 77 can generate a controlled diffusion so as to obtain a beam with a controlled blending effect particularly useful in the projection of coloured light beams .

The movement of the main reflector 3 between the collimated beam position, also called NARROW (illustrated in Figure 3) and the divergent beam position, also called WIDE (illustrated in Figure 4) , determines a variation of the amplitude of the projected beam (as is highlighted in the schematic representations of Figures 3 and 4) . Advantageously, in this manner the beam exit angle (indicated by p in the accompanying figures) can vary from a minimum of 5° (Figure 3) to a maximum of 70° (Figure 4) .

Furthermore, the light guides 60, in addition to substantially collecting all the light radiations emitted by the linear light sources 7 and conveying them towards the further reflector 70 and then towards the main reflector 3, have a protective and closing function of the main chamber 8 in which the main reflector 3 is housed.

Finally, it is evident that modifications and variations can be made to the light fixture and to the method described herein without departing from the scope of protection of the appended claims.