Abstract:
A cable lighting system includes two conductive cables and a flat illumination device supported by the two conductive cables. The flat illumination device uses a flat illumination body for providing uniform illumination, which greatly reduces illumination concentration as a convention spot light source does. Furthermore, the flat illumination body is supported by the two conductive cables through two supports disposed spaced at two opposite sides of the flat illumination body. Each support is supported at one point for each conductive cable, so the flat illumination device as a whole is supported by the two conductive cables at the four points and can keep steady easily. Therein, the flat illumination body is pivotally connected to the two supports disposed spaced, so the flat illumination body can be rotated relative to the supports individually for a required orientation without excessive change in the relative disposition of the supports to the conductive cables.

Description:
BACKGROUND OF THE INVENTION 
       [0001]    1. Field of the Invention 
         [0002]    The invention relates to a lighting system, and especially relates to a cable lighting system. 
         [0003]    2. Description of the Prior Art 
         [0004]    For conventional cable lighting systems, two electric cables, of which ends usually are fixed on walls, support at least one illumination device and provide electricity thereto. The illumination device usually includes a single supporting structure and a spot light source. The single supporting structure hangs on two electric cables and carries the spot light source. Because of noticeable illumination concentration of spot light, it is difficult to establish uniform illumination onto a larger area even by a plurality of spot light sources. 
       SUMMARY OF THE INVENTION 
       [0005]    An objective of the invention is to provide a cable lighting system which uses a flat illumination device, of which a flat illumination body is supported by two cables through two supports disposed spaced at two opposite sides of the flat illumination body, for establishing uniform illumination. 
         [0006]    A cable lighting system according to the invention includes two conductive cables and a flat illumination device. The two conductive cables are disposed spaced. Each end of the two conductive cables is fixedly disposed, for example on walls. The flat illumination device includes two supports and a flat illumination body. The two supports disposed spaced. Each support is supported by the two conductive cables. The flat illumination body is pivotally connected to and between the two supports. The flat illumination body is electrically connected to the two conductive cables through at least one of the two supports. Because the flat illumination body can provide more uniform illumination than a convention spot light source, the cable lighting system can establish uniform illumination onto a relatively larger area easily. In addition, each support is supported at one point for each conductive cable, so the flat illumination device as a whole is supported by the two conductive cables at the four points and can keep steady easily. Furthermore, the flat illumination body can be rotated relative to the supports individually for a required orientation without excessive change in the relative disposition of the supports to the conductive cables. 
         [0007]    These and other objectives of the present invention will no doubt become obvious to those of ordinary skill in the art after reading the following detailed description of the preferred embodiment that is illustrated in the various figures and drawings. 
     
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         [0008]      FIG. 1  is a schematic diagram illustrating a cable lighting system of an embodiment according to the invention. 
           [0009]      FIG. 2  is a partially exploded view of a flat illumination device of the cable lighting system in  FIG. 1 . 
           [0010]      FIG. 3  is an exploded view of a flat illumination body of the flat illumination device in  FIG. 2 . 
           [0011]      FIG. 4  is an exploded view of a support of the flat illumination device in  FIG. 2 . 
           [0012]      FIG. 5  is an enlarged section view of a portion of the cable lighting system in  FIG. 1 . 
           [0013]      FIG. 6  is a schematic diagram illustrating a cable lighting system of another embodiment according to the invention. 
           [0014]      FIG. 7  is a partially exploded view of the cable lighting system in  FIG. 6 . 
           [0015]      FIG. 8  is an exploded view of a support of a flat illumination body of the cable lighting system in  FIG. 6 . 
           [0016]      FIG. 9  is a top view of the cable lighting system in  FIG. 6 . 
       
    
    
     DETAILED DESCRIPTION 
       [0017]    Please refer to  FIG. 1 .  FIG. 1  is a schematic diagram illustrating a cable lighting system  1  of an embodiment according to the invention. The cable lighting system  1  can be used for indoor illumination and includes two conductive cables  10  and  11  and a flat illumination device  12 . The two conductive cables  10  are disposed spaced and extend in a direction D 1 . Both ends of each conductive cable  10  and  11  are fixedly disposed, for example on walls. The flat illumination device  12  includes two supports  120  and  121  and a flat illumination body  122 . The two supports  120  and  121  are disposed spaced. Each support  120  and  121  is supported by the two conductive cables  10  and  11 . The flat illumination body  122  is pivotally connected to and between the two supports  120  and  121 , so that the flat illumination body  122  hangs on the two conductive cables  10  and  11  through the two supports  120  and  121  (at two opposite sides of the flat illumination body  122 ) and can rotate relative to the two conductive cables  10  and  11  (as shown in dashed lines). The two conductive cables  10  and  11  carry electricity for providing a voltage (or electric potential difference) required by the flat illumination body  122 . The flat illumination body  122  is electrically connected to the two conductive cables  10  and  11  through at least one of the two supports  120  and  121 , so that the flat illumination body  122  can be powered to emitting light. 
         [0018]    Please also refer to  FIG. 2  to  FIG. 3 .  FIG. 2  is a partially exploded view of the flat illumination device  12 .  FIG. 3  is an exploded view of the flat illumination body  122 . In the embodiment, the flat illumination body  122  includes a back cover  1220 , two opposite side frames  1222  and  1223 , a light guiding plate  1224 , and two light bars  1226 . The back cover  1220  has a back portion  12200  and two side slots  12202  disposed at two opposite sides of the back portion  12200 . The two side frames  1222  and  1223  are connected to the back cover  1220  at another two opposite sides of the back portion  12200  respectively. The back cover  1220  and the side frames  1222  and  1223  substantially form a recess for receiving the light guiding plate  1224  and the two light bars  1226 . The flat illumination body  122  is pivotally connected to the two supports  120  and  121  through the two opposite side frames  1222  and  1223  respectively. In the embodiment, the back cover  1220  can be an integrated part formed by pressing a metal plate, but the invention is not limited thereto. For example, the back cover  1220  can be an assembly of several components. 
         [0019]    The light guiding plate  1224  has a light-emitting surface  12240 , a back surface  12242  opposite to the light-emitting surface  12240 , and two edge portions  12244  at two opposite sides of the light-emitting surface  12240 . The two edge portions  12244  are disposed in the two side slots  12202  respectively. The back surface  12242  is toward the back portion  12200 . The two light bars  1226  are disposed in the two side slots  12202  toward the corresponding edge portions  12244  respectively. Thereby, light produced by the light bars  1226  can enter the light guiding plate  1224  from the edge portions  12244  and then is emitted out of the light guiding plate  1224  from the light-emitting surface  12240 . For enhancement of emitting efficiency, it is practicable to dispose a reflection layer or sheet between the back surface  12242  and the back portion  12200  (e.g. on the back surface  12242  or on the surface of the back portion  12200  facing the back surface  12242 ). In addition, in the embodiment, each light bar  1226  is attached into the corresponding slot  12202  through a heat conductive adhesive or tape  1227 , which is conducive to dissipating heat produced by the light bars  1226  in operation through the back cover  1220 . 
         [0020]    In the embodiment, each side frame  1223  has a step. Another two edge portions  12246  of the light guiding plate  1224  are disposed on the steps. In other words, the circumference of the light guiding plate  1224  is held by the two side slots  12202  of the back cover  1220  and the two steps of the two side frames  1223 , which is conducive to the fixity of the light guiding plate  1224 . In addition, in the embodiment, the flat illumination body  122  is pivotally connected to the two supports  120  and  121  through two pivots  124  and  125  respectively. The pivots  124  and  125  are integrated into the side frames  1222  and  1223  respectively, but the invention is not limited thereto. For example, the pivots  124  and  125  are integrated into the supports  120  and  121  respectively, or the pivots  124  and  125  are individual parts. Therefore, the two side frames  1222  and  1223  are pivotally connected to the two supports  120  and  121  through the two pivots  124  and  125  respectively. 
         [0021]    Please also refer to  FIG. 4  and  FIG. 5 .  FIG. 4  is an exploded view of the support  120 .  FIG. 5  is an enlarged section view of a portion of the cable lighting system  1 . In the embodiment, the support  120  includes a structural member  1200 , two electrical joining members  1202  and  1203 , and two conducting parts  1204  and  1205 . The support  120  is pivotally connected to the corresponding side frame  1222  through the structural member  1200 . The structural member  1200  is achieved by a casing capable of accommodating other components therein, such as the electrical joining members  1202  and  1203  and the conducting parts  1204  and  1205 . The structural member  1200  has a pivot hole engaging with the pivot  124 , so that the structural member  1200  is pivotally connected to the corresponding side frame  1222  through the pivot  124 . 
         [0022]    The two electrical joining members  1202  and  1203  are fixedly disposed on the structural member  1200  and electrically join the two conducting parts  1204  and  1205  with the two conductive cables  10  and  11  respectively. The electrical joining member  1203  includes a conductive main body  12030  and a conductive screw  12032 . The conductive main body  12030  is fixedly disposed on the structural member  1200  and has a thread hole  12030   a  and an open slot  12030   b  passing through the thread hole  12030   a . The corresponding conductive cable  11  passes through the open slot  12030   b . The conductive screw  12032  is screwed into the thread hole  12030   a  to fix the corresponding conductive cable  11  in the open slot  12030   b  and electrically connected with the corresponding conductive cable  11 . In the embodiment, the conductive screw  12032  has a sharp tip  12032   a . The sharp tip  12032   a  pricks the corresponding conductive cable  11 . Thereby, the sharp tip  12032   a  contributes the fixing of the corresponding conductive cable  11  in the open slot  12030   b  and the electrical connection of the corresponding conductive cable  11  with the conductive main body  12030 . Furthermore, in the embodiment, the corresponding conductive cable  11  includes a central conductor  110  and an insulation jacket  112 . The central conductor  110  is sheathed with the insulation jacket  112 . The conductive screw  12032  pricks the insulation jacket  112  with the sharp tip  12032   a  and then contacts the central conductor  110 . In addition, for a case that the corresponding conductive cable  11  is a bare cable, the conductive screw  12032  without the sharp tip  12032   a  still can clamp the corresponding conductive cable  11  in the open slot  12030   b  firmly. 
         [0023]    The two conducting parts  1204  and  1205  are disposed on the structural member  1200 . The conducting part  1205  is electrically connected to the electrical joining member  1203  by attaching one end of the conducting part  1205  to the conductive main body  12030  of the electrical joining member  1203 . The attachment is achieved by a similar way to that for electrically connecting the cable  11  with the electrical joining member  1203 ; however, the invention is not limited thereto. For example, the end of the conducting part  1205  can be soldered onto the conductive main body  12030 , or the end of the conducting part  120  wraps around a post or screw attached the conductive main body  12030 , or the end of the conducting part  1205  is clamped by a clip attached the conductive main body  12030 . In addition, in the embodiment, the conducting part  1205  is a conductive wire, but the invention is not limited thereto. For example, the conducting part  1205  can be a bare wire, or a conductive part embedded in the structural member  1200  (e.g. by an insert molding process used for forming the structural member  1200 ). The two conducting parts  1204  and  1205  are also electrically connected to the flat illumination body  122 . In the embodiment, the pivot  124  has a through hole  124   a , which the conducting parts  1204  and  1205  pass through into the flat illumination body  122  for electrically connecting with at least one light bar  1226 . In addition, in the embodiment, the light bars  1226  use LEDs mounted on a circuit board as lighting source. The conductive cables  10  and  11  carry low voltage about 12V. However, the invention is not limited thereto. In practice, what kind of voltage the conductive cables  10  and  11  carry depends on what the flat illumination devices  1  needs or more exactly what the light bars  1226  need. Furthermore, the conductive cables  10  and  11  are not limited to be identical. For example, one is a cable with sheath while the other is a bare cable. 
         [0024]    In addition, in the embodiment, the two electrical joining members  1202  and  1203  are the same, the conducting parts  1204  and  1205  are the same, and the conductive cables  10  and  11  have the same structure. For the details of the electrical joining member  1202 , the conductive cable  10 , and the conducting part  1204 , please refer to the relevant description of the electrical joining member  1203 , the conductive cable  11 , and the conducting part  1205  respectively and will not be described repeatedly. However, the invention is not limited thereto. In addition, the electrical joining member according to the invention is not limited to the above electrical joining member  1203 . For example, an electrical joining member according to the invention can use a conductive clip to clip a conductive cable (e.g. a bare conductive cable), which also can achieve the purposes of fixing the support on the conductive cable and electrically connecting the electrical joining member with the conductive cable. 
         [0025]    In addition, in the embodiment, the supports  120  and  121  are substantially symmetrical, so the details of the support  121  can be understood by referring to the relevant description of the support  120  and will not be described repeatedly. In the embodiment, the two lighting bars  1226  are powered through the supports  120  and  121  respectively. However, the invention is not limited to the fact that the supports  120  and  121  are substantially symmetrical. For example, the support  120  can be used for providing supporting and electricity to the flat illumination body  122  while the support  121  can be used only for supporting the flat illumination body  122  without supply of electricity. In this case, the support  121  can be provided without conducting parts (such as the conducting parts  1204  and  1205 ) and can be realized by a rod part with a clip at each end thereof for clipping the two conductive cables  10  and  11 . 
         [0026]    Furthermore, in the embodiment, each support  120  and  121  shows a straight bar, so when the supports  120  and  121  are installed onto the conductive cables  10  and  11  by their end portions, the flat illumination device  1  and the conductive cables  10  and  11  are disposed on the same plane in logic and the flat illumination body  122  is located between the two conductive cables  10  and  11 . In another aspect, the flat illumination body  122  and the two cables  10  and  11  are substantially coplanarly disposed, and the flat illumination body  122  is between the conductive cables  10  and  11 . Therefore, the cable lighting system  1  occupies less space than a conventional cable lighting system of which a spot light source is much lower than cables. In practice, such feature makes the flat illumination device  12  capable of being used like an embedded ceiling light when the conductive cables  10  and  11  are disposed close to a ceiling. 
         [0027]    In addition, the two side frames  1222  and  1223  are pivotally connected to the two supports  120  and  121  in an axis A 1  (indicated by a center line) parallel to the direction D 1  in which the two conductive cables  10  and  11  extend. When the flat illumination body  122  shows a rectangle profile of which the long side is parallel to the axis A 1 , a rotation adjustment operation on the flat illumination body  122  (e.g. rotating the flat illumination body  122  about the axis A 1  for a required orientation) involves a smaller space. Furthermore, the supports  120  and  121  is located at two opposite sides of the flat illumination device  12 , so a user can easily arrange a plurality of flat illumination devices  1  one after another in a row on the conductive cables  10  and  11  without interference with each other. By the arrangement of the flat illumination devices  1 , a uniform illumination extension can be easily obtained. 
         [0028]    As discussed above, the flat illumination device  1  and the conductive cables  10  and  11  are substantially coplanarly disposed, but the invention is not limited thereto. Please refer to  FIG. 6  and  FIG. 7 .  FIG. 6  is a schematic diagram illustrating a cable lighting system  3  of another embodiment according to the invention.  FIG. 7  is a partially exploded view of the cable lighting system  3 . In the embodiment, the cable lighting system  3  is logically similar to the cable lighting system  1 . For simplification of the cable lighting system  3 , the cable lighting system  3  is illustrated with the same reference numbers used in the cable lighting system  1  for the same components. For other descriptions about these components, please refer to the relevant descriptions of the components with the same reference numbers in the cable lighting system  1 . In the embodiment, the cable lighting system  3  includes two conductive cables  10  and  11  and a flat illumination device  32 . The flat illumination device  32  includes two supports  320  and  321  and a flat illumination body  122 . The flat illumination body  122  is pivotally connected to the two supports  320  and  321  through pivots  124  and  125  respectively. Each of the two supports  320  and  321  is supported by the two conductive cables  10  and  11 . Thereby, the flat illumination body  122  hangs on the two conductive cables  10  and  11  through the two supports  320  and  321  and can rotate relative to the two conductive cables  10  and  11  (as shown in dashed lines). 
         [0029]    Please also refer to  FIG. 8 .  FIG. 8  is an exploded view of the support  320 . The support  320  includes a structural member  3200 , two conductive extension members  3202  and  3203 , two electrical joining members  3204  and  3205 , and two conducting parts  3206  and  3207 . The support  320  is pivotally connected to the corresponding side frame  1222  through the structural member  3200 . The structural member  3200  is achieved by a casing capable of accommodating other components therein, such as the conducting parts  3206  and  3207 . The structural member  3200  has a pivot hole engaging with the pivot  124 , so that the structural member  3200  is pivotally connected to the corresponding side frame  1222  through the pivot  124 . The two conductive extension members  3202  and  3203  are connected to the structural member  3200 . The two electrical joining members  3204  and  3205  electrically join the two conductive extension members  3202  and  3203  with the two conductive cables  10  and  11  respectively. Thereby, the support  320  is supported by the two conductive cables  10  and  11  through the two electrical joining members  3204  and  3205 . 
         [0030]    In the embodiment, the electrical joining member  3205  is fixedly connected to the corresponding conductive extension member  3203  and includes a conductive main body  32050  and a conductive screw  32052 . The conductive main body  32050  has a thread hole  32050   a  and an open slot  32050   b  passing through the thread hole  32050   a . The corresponding conductive cable  11  passes through the open slot  12030   b . The conductive screw  32052  is screwed into the thread hole  32050   a  to fix the corresponding conductive cable  11  in the open slot  32050   b  and electrically connected with the corresponding conductive cable  11 . In the embodiment, the conductive screw  32052  has a sharp tip  32052   a . The sharp tip  32052   a  pricks the corresponding conductive cable  11 . Thereby, the sharp tip  32052   a  contributes the fixing of the corresponding conductive cable  11  in the open slot  32050   b  and the electrical connection of the corresponding conductive cable  11  with the conductive main body  32050 . For a case that the corresponding conductive cable  11  includes a central conductor  110  sheathed with an insulation jacket  112 , the conductive screw  32052  pricks the insulation jacket  112  with the sharp tip  32052   a  and then contacts the central conductor  110 . For another case that the corresponding conductive cable  11  is a bare cable, the conductive screw  32052  without the sharp tip  32052   a  still can clamp the corresponding conductive cable  11  in the open slot  32050   b  firmly. In addition, the electrical joining member according to the invention is not limited to the above electrical joining member  3205 . For example, an electrical joining member according to the invention can use a conductive clip to clip a conductive cable (e.g. a bare conductive cable), which also can achieve the purposes of fixing the support on the conductive cable and electrically connecting the electrical joining member with the conductive cable. 
         [0031]    In the embodiment, the conductive extension member  3203  is a metal rod. The conductive main body  32050  has a through hole  32050   c . The corresponding conductive extension member  3203  passes through the through hole  32050   c  for fixing the electrical joining member  3205  thereon. The location of the conductive main body  32050  on the conductive extension member  3203  can be adjusted by sliding the conductive main body  32050  relative to the conductive extension member  3203 . In practice, the conductive extension member  3203  can be joined with the electrical joining member  3205  by a similar way to that for electrically connecting the cable  11  with the electrical joining member  3205 ; however, the invention is not limited thereto. For example, the conductive extension member  3203  and the electrical joining member  3205  are joined by a screw and a thread hole engaging with each other. For example, the through hole  32050   c  can be implemented by a rotatable nut (of which a thread hole functions as the through hole  32050   c ) disposed on the conductive main body  32050 . Correspondingly, the conductive extension member  3203  has a threaded portion engaging with the rotatable nut. By rotating the nut, the conductive main body  32050  can move along the conductive extension member  3203 . In other words, the location of the flat illumination body  122  relative to the two conductive cables  10  and  11  is adjustable. 
         [0032]    In the embodiment, the two conducting parts  3206  and  3207  are disposed on the structural member  3200  and are electrically connected to the two conductive extension members  3202  and  3203  through two conducting posts  3208  and  3209  respectively. Each conducting post  3208  and  3209  includes a mounted boss with a thread hole, and a fixing screw. The conducting posts  3208  and  3209  pass through a side wall of the structural member  3200  so that two ends of the conducting parts  3206  and  3207  are connected to the conducting posts  3208  and  3209  inside respectively (for example by wrapping around the posts  3208  and  3209 ) and two ends of the conductive extension members  3202  and  3203  are connected to conducting posts  3208  and  3209  outside respectively (further with a fixing part for fixing the two ends on the posts  3208  and  3209 ). In the embodiment, the two conducting parts  3206  and  3207  are conductive wires, but the invention is not limited thereto. For example, the conducting parts  3206  and  3207  can be bare wires, or conductive parts embedded in the structural member  3200  (e.g. by an insert molding process used for forming the structural member  3200 ). In the embodiment, the two conducting parts  3206  and  3207  are also electrically connected to the flat illumination body  122 . The conducting parts  3206  and  3207  pass through the through hole  124   a  of the pivot  124  into the flat illumination body  122  for electrically connecting with at least one light bar  1226 . 
         [0033]    In addition, in the embodiment, the supports  320  and  321  are substantially symmetrical, so the details of the support  321  can be understood by referring to the relevant description of the support  320  and will not be described repeatedly. In the embodiment, the two lighting bars  1226  are powered through the supports  320  and  321  respectively. However, the invention is not limited to the fact that the supports  320  and  321  are substantially symmetrical. For example, the support  320  can be used for providing supporting and electricity to the flat illumination body  122  while the support  321  can be used only for supporting the flat illumination body  122  without supply of electricity. In this case, the support  321  can be provided without conducting parts (such as the conducting parts  3206  and  3207 ) and can be realized by a pivotal part and two extension members connected to the pivotal part. A clip is provided at each end of the two extension members for clipping the two conductive cables  10  and  11 . 
         [0034]    In the above embodiment, the flat illumination devices  12  and  32  hang on the conductive cables  10  and  11  by four points, so the structural stability is better than that of a convention spot light source which hangs on cable lights usually by two points. For more details, please also refer to  FIG. 9  which is a top view of the cable lighting system  1 . 
         [0035]    A plane is defined, on which the two conductive cables  10  and  11  are located. The view plane of  FIG. 9  can be considered as the plane for simplification of illustration. The electrical joining members of the two supports  320  and  321  connect with four points P 1 , P 2 , P 3  and P 4  (indicated by cross marks) of the two conductive cables  10  and  11 . The four points P 1 , P 2 , P 4  and P 3  form an area (presented by a polygon in dashed lines with hatch lines inside) on the plane parallel to the two conductive cables  10  and  11 . A profile projection of the flat illumination body  122  on the plane is within the area. When the flat illumination device  12  is vertical hanged on the conductive cables  10  and  11 , the line of gravity of the flat illumination device  12  will always pass through the area even with change in the gravity of the flat illumination device  12  (for example due to a rotation). In another aspect, a change in the gravity of the flat illumination device  12  may induce a new state of equilibrium (involving new balanced forces at the four points P 1 , P 2 , P 3  and P 4 ), but no torque (or moment) is produced at the four points P 1 , P 2 , P 3  and P 4  in principle. The above feature also exists in the cable lighting system  3 . Therefore, the flat illumination devices  12  and  32  can be stably supported when vertically hanging on the conductive cables  10  and  11 . 
         [0036]    In addition, in the cable lighting system  1  (referring to FIG.  1 ), the two supports  120  and  121  are connected to the side frames  1222  and  1223  individually. That is, each support  120  and  122  can be rotate relative to the flat illumination body  122  individually. For a case that the conductive cables  10  and  11  are a little non-parallel, supports  120  and  121  can adapt to the non-parallel problem by being rotated relative to the conductive cables  10  and  11  individually, so that the flat illumination body  122  can remain its original orientation. The above feature also exists in the cable lighting system  3 . The adaptation of the supports  320  and  321  to the proper non-parallel problem of the conductive cables  10  and  11  can be understood by referring to the above description and will not be repeated in addition. 
         [0037]    Those skilled in the art will readily observe that numerous modifications and alterations of the device and method may be made while retaining the teachings of the invention. Accordingly, the above disclosure should be construed as limited only by the metes and bounds of the appended claims.