Patent Publication Number: US-6712488-B2

Title: Globe type electrodeless lighting apparatus

Description:
BACKGROUND OF THE INVENTION 
     1. Field of the Invention 
     The present invention relates to an electrodeless lighting apparatus, and particularly, to a globe type electrodeless lighting apparatus which is able to extend a lighting area with a simple structure. 
     2. Description of the Background Art 
     Generally, an electrodeless lighting apparatus is a device emitting visible rays or ultraviolet rays by radiating microwave to an electrodeless bulb. In addition, the electrodeless lighting apparatus has longer life span than that of an incandescent lamp or a fluorescent lamp, and has superior lighting effect. 
     FIG. 1 is a longitudinal cross-sectional view showing an electrodeless lighting apparatus according to the conventional art. 
     As shown therein, the conventional electrodeless lighting apparatus comprises: a case  10 ; a high voltage generator  20  installed in the case  10  for generating high voltage; a magnetron  30  installed in the case  10  apart a certain distance from the high voltage generator  20  for generating microwave using the high voltage generated in the high voltage generator  20 ; a waveguide  40  for guiding the microwave generated in the magnetron  30 ; an electrodeless bulb  60  protruded in front of the waveguide  40  for emitting light as a material filled in the bulb  60  becomes plasma by the microwave energy; and a mesh screen  50  covered on front side of the bulb  60  for blocking the microwave and passing the light emitted from the bulb  60 . 
     Also, the lighting apparatus comprises: a mirror  70  installed on an outlet portion of the waveguide  40  for reflecting the light generated in the bulb  60  to frontward; and a reflector  80  installed on outer side of the case  10  for reflecting the light generated in the bulb  60 . 
     On the other hand, the case  10  includes a bulb motor  90  for rotating the bulb  60 , and a bulb shaft  91  for connecting the bulb motor  90  to the bulb  60 . Also, a cooling fan  100  for releasing heat generated in the high voltage generator  20  and in the magnetron  30  and a fan motor  101  for driving the cooling fan  100  are installed in the case  10 . In addition, an air guide  110  for guiding an air flow generated by the cooling fan  100  to the high voltage generator  20  and to the magnetron  30  is included in the case  10 . 
     An operation of the electrodeless lighting apparatus according to the conventional art constructed as above will be described as follows. 
     When an electric source is applied to the high voltage generator  20 , the magnetron  30  generates microwave by the high voltage generated in the high voltage generator  20 . The microwave generated in the magnetron  30  is transmitted into the mesh screen  50  through the waveguide  40  to discharge the material filled in the bulb  60 , and thereby plasma is generated. 
     The light emitted by generating plasma in the bulb  60  is reflected on the mirror  70  and the reflector  80  and radiated to frontward. 
     At the same time, the bulb motor  90  is operated to rotate the bulb  60 , and accordingly, the bulb  60  is cooled down. In addition, the bulb motor  90  is operated to rotate the cooling fan  100 , and accordingly, outer air is induced through the air guide  110  to cool down the high voltage generator  20  and the magnetron  30 . 
     On the other hand, as shown in FIG. 2, the reflector  80  which reflects the light generated in the bulb  60  comprises a parabola surface portion  81  including an opening hole  83  formed on front surface, and a coupling portion  82  extended from a rear part of the parabola surface portion  81  and coupled to the case  10 . 
     The reflector  80  is made using a metal material, and a reflection film is coated on an inner surface of the parabola surface portion  81 . 
     The coupling portion  82  of the reflector  80  is fixedly coupled to the case  10 , and at that time, the bulb  60  and the mesh screen  50  are located inside of the reflector  80 . 
     In addition, a light guide  120  of long cylinder shape having a diameter corresponding to the diameter of the opening hole  83  of the reflector in order to illuminate outdoor and indoor with the light generated in the bulb  60  is coupled so as to be connected to the opening hole  83  of the reflector  80 . One or more light guide  120  may be coupled. 
     In the above structure of the lighting apparatus, the light generated in the bulb  60  is reflected on the mirror  70  and the reflector  80 , and then goes to the light guide  120 . And the outdoor or indoor is illuminated as the light reflected on the mirror  70  and the reflector  80  passes through the light guide  120 . 
     However, according to conventional electrodeless lighting apparatus, the reflector  80  and the light guide  120  should be included in order to illuminate the outdoor or the indoor, and therefore, initial cost is increased. In addition, lengths of the reflector  80  and the light guide  120  are very long, and therefore, it needs a large installation area, and the installation area is limited. 
     Also, the reflector  80  is formed to have parabola cross section for reflecting the light straightly, and therefore, the reflector  80  is heated by the heat generated from the bulb  60  which is located inside of the reflector  80 . In addition, a life span is reduced by the heat of the reflector  80 . 
     SUMMARY OF THE INVENTION 
     Therefore, an object of the present invention is to provide a globe type electrodeless lighting apparatus which is able to illuminate omnidirection with a simple structure. 
     Another object of the present invention is to provide a globe type electrodeless lighting apparatus which is able to minimize glaring phenomenon and to release the heat generated therein by installing an irregularly reflecting globe around a bulb. 
     Still another object of the present invention is to provide a globe type electrodeless lighting apparatus which is able to prevent globe from being distorted or being reduced its life span by the heat generated in the bulb. 
     To achieve these and other advantages and in accordance with the purpose of the present invention, as embodied and broadly described herein, there is provided a globe type electrodeless lighting apparatus comprising: a waveguide for transmitting microwave which is generated in a magnetron; a mesh screen coupled on an outlet portion of the waveguide for blocking a leakage of the microwave and passing the light; a bulb located in the mesh screen for emitting light as generating plasma by the microwave; and a globe installed outer periphery of the mesh screen so that the light generated in the bulb to omnidirections. 
     Also, the globe is formed using a material having irregularly reflecting characteristic, 50%˜95% light permeability, and heat resistance temperature of higher than 100° C. 
     A location of the bulb and a shape of the globe are decided so that an illuminating angle can be larger than 270° C. centering around the bulb. 
     The waveguide is fixed on inside of the case, and the globe is fixed on outer side of the case. In addition, the globe of spherical or polyhedral shape comprises a permeation portion through which the light passes, and a mounting portion extended from the permeation portion as a cylindrical shape and coupled to the case. 
     According to an embodiment of the present invention, the globe may be formed as a sphere or a polyhedron. 
     According to another embodiment of the present invention, the globe includes a plurality of fine protrusions at least one surface between an inner surface and an outer surface of the globe. 
     The fine protrusion is formed as a pentahedron or as a hemisphere. 
     According to still another embodiment of the present invention, a heat blocking member is installed between the bulb and the globe which is close to the bulb so that the heat transmitted from the bulb can be blocked. 
     The heat blocking member of ring shape comprises a plurality of louvers located between the mesh screen and the globe, and the plurality of louvers are connected to each other using connecting portions. 
     The louver is formed to have a structure which is gradually enlarged toward the front side. 
     According to the electrodeless lighting apparatus of the present invention as described above, the structure of the lighting apparatus can be simple and omnidirectional lighting effect can be performed by installing the globe around the bulb instead of using a reflector and a light guide. 
     The foregoing and other objects, features, aspects and advantages of the present invention will become more apparent from the following detailed description of the present invention when taken in conjunction with the accompanying drawings. 
    
    
     BRIEF DESCRIPTION OF THE DRAWINGS 
     The accompanying drawings, which are included to provide a further understanding of the invention and are incorporated in and constitute a part of this specification, illustrate embodiments of the invention and together with the description serve to explain the principles of the invention. 
     In the drawings: 
     FIG. 1 is a longitudinal cross-sectional view showing an electrodeless lighting apparatus according to the conventional art; 
     FIG. 2 is a cross-sectional view showing a state that a light guide is connected to the conventional lighting apparatus; 
     FIG. 3 is a longitudinal cross-sectional view showing an electrodeless lighting apparatus according to a first embodiment of the present invention; 
     FIG. 4 is a cross-sectional view showing operation state of principal parts in the electrodeless lighting apparatus according to the first embodiment of the present invention; 
     FIG. 5 is a cross-sectional view showing principal parts of an electrodeless lighting apparatus according to a second embodiment of the present invention; 
     FIG. 6 is a longitudinal cross-sectional view showing an electrodeless lighting apparatus according to a third embodiment of the present invention; 
     FIGS. 7 and 8 are views showing various modified embodiments of the electrodeless lighting apparatus according to the third embodiment of the present invention; 
     FIG. 9 is a cross-sectional view showing an electrodeless lighting apparatus according to a fourth embodiment of the present invention; 
     FIG. 10 is a cross-sectional view showing an electrodeless lighting apparatus according to a fifth embodiment of the present invention; and 
     FIG. 11 is a cross-sectional view showing an operation state of the electrodeless lighting apparatus according to the fifth embodiment of the present invention. 
    
    
     DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS 
     Reference will now be made in detail to the preferred embodiments of the present invention, examples of which are illustrated in the accompanying drawings. 
     For same components as those of the conventional art, same reference numerals are used. 
     FIG. 3 is a longitudinal cross-sectional view showing an electrodeless lighting apparatus according to a first embodiment of the present invention. 
     As shown therein, the electrodeless lighting apparatus according to the first embodiment of the present invention comprises: a high voltage generator  20  for generating high voltage mounted on inner front surface of a case  10 ; and a magnetron  30  located on a position a predetermined distance apart from the high voltage generator  20  for generating microwave by being transmitted the high voltage generated in the high voltage generator  20 . 
     In addition, a waveguide  40  for transmitting the microwave generated in the magnetron  30  is installed between the magnetron  30  and the high voltage generator  20 , and a mesh screen  50  for forming a resonating region of the microwave transmitted from the waveguide  40  is installed on an outlet portion  41  of the waveguide  40 . 
     Herein, the mesh screen  50  is formed as a cylinder having a mesh structure so as to block the microwave and pass the light. 
     In addition, a bulb  60 , in which illuminant materials are filled, is located in the mesh screen  50 , and the filled material may include metal which emits light as generating plasma by the microwave. 
     A bulb motor  90  for rotating the bulb  60  and a bulb shaft  91  for connecting the bulb motor  90  to the bulb  60  are included in the case  10 . In addition, a cooling fan  100  and a fan motor  101  driving the fan  100  are installed on the case  10  in order to release the heat generated from the high voltage generator  20  and the magnetron  30 , and an air guide  110  for guiding an air flow generated by the cooling fan  100  to a direction of the high voltage generator  20  and the magnetron  30  is included. 
     Especially, a globe  130  which is formed as a sphere so as to cover the mesh screen  50  is installed on a front surface of the case  10 . Therefore, the mesh screen  50  is located inside of the globe  130 , and the bulb  60  is located in the mesh screen  50 . 
     The globe  130  of spherical shape comprises a permeation portion  131  through which the light is permeated to outside, and a mounting portion  132  protruded from the permeation portion  131  and coupled to the case  10 . Herein, the mounting portion  132  includes a neck portion  132   a  which is inserted into an outer side of the outlet portion  41  on the waveguide  40 , and a flange portion  132   b  which is extended to a radial direction so as to be coupled to the case  10  using a bolt  135  and fixed thereon is formed on an end of the neck portion  132   a.    
     It is desirable that the globe  130  is formed using an irregularly reflecting material such as polymer. In addition, it is desirable that a permeability of the material is 50%˜95%, and a heat resistance temperature is 100° or more. 
     On the other hand, a mirror  70  for reflecting the light generated in the bulb  60  forward is mounted on a rear side of the bulb  60  in the outlet portion of the waveguide  40 . The microwave can be passed through the mirror  70 . 
     In addition, it is desirable that the location of the bulb  60  and the shape of the globe  130  are decided so that a lighting angle is to be 270°. 
     An operation and an effect of the electrodeless lighting apparatus according to the first embodiment of the present invention will be described as follows. 
     When an electric source is applied to the high voltage generator  20 , the magnetron  30  generates microwave by the high voltage generated in the high voltage generator  20 . The microwave generated in the magnetron  30  is transmitted into the mesh screen  50  through the waveguide  40 , and then, a strong microwave electric field is generated in the mesh screen  50  to generate plasma as exciting the material filled in the bulb  60 . 
     The light emitted by the plasma generated in the bulb  60  is permeated through the globe  130  formed as a sphere, and then radiated to omnidirection in the lighting area. In addition, the light radiated to a rear direction of the bulb  60  is reflected forward by the mirror  70 , and then radiated to outer side after permeating the globe  130 . 
     Herein, the globe  130  is made by the irregularly reflecting material, and therefore, the light permeating the globe is irregularly reflected to omnidirection. Therefore, the glaring phenomenon that a user in the lighting area may feel can be minimized. 
     On the other hand, as the electric source is applied, the bulb motor  90  is operated to rotate the bulb  60 , and thereby, the bulb  60  is cooled down. Also, the fan motor  101  is operated and rotates the cooling fan  100 , and accordingly, the outer air is induced into the case  10  through the air guide  100  to cool down the high voltage generator  20  and the magnetron  30 . 
     In the electrodeless lighting apparatus according to the present invention, the light emitted as the material filled in the bulb  60  becomes plasma by the microwave is the light having same characteristics as those of natural rays such as visible rays or ultraviolet rays. As described above, the light generated in the bulb  60  permeates the globe  130  of spherical shape and illuminated indoors or outdoors, and therefore, the light is radiated to omnidirection. 
     Also, the globe  130  is made using the irregularly reflecting material, and therefore, the light emitted from the bulb  60  is irregularly reflected as passing through the globe  130 . Thereby the glaring phenomenon that the user may feel can be minimized. 
     Also, according to the present invention, the light generated in the bulb  60  is radiated to outer side using the globe  130 , and therefore, the omnidirectional lighting can be made and the entire structure of the lighting apparatus can be simplified. That is, according to the conventional art, the light guide  120  should be included in the lighting apparatus as shown in FIG. 1, however, the present invention requires only the globe  130 . Therefore, the entire structure of the lighting apparatus can be constructed simply. 
     FIG. 5 is a cross-sectional view showing principal parts of an electrodeless lighting apparatus according to a second embodiment of the present invention. 
     The lighting apparatus according to the second embodiment of the present invention has same construction as that of the lighting apparatus of the first embodiment except a shape of a globe  140 . 
     That is, the globe  130  in the first embodiment is formed as a pure sphere, however, the globe  140  of the second embodiment is formed as a polyhedron having a plurality of planes as shown in FIG.  5 . 
     The polyhedron globe  140  is also formed using an irregularly reflecting material same as the first embodiment, and it is desirable that the material has 50%˜95% light permeability, and 100° C. heat resistance temperature. 
     Herein, the shape of the polyhedron globe  140  is not limited to the shape shown in FIG. 5, however, may be formed variously such as a hexahedron, or an octahedron besides the tetrahedron shown in FIG.  5 . 
     In the electrodeless lighting apparatus according to the second embodiment of the present invention, the light emitted from the bulb  60  is omnidirectionally reflected through the polyhedron globe  140  formed as a polyhedron shape, and illuminates the lighting area. 
     FIG. 6 is a longitudinal cross-sectional view showing an electrodeless lighting apparatus according to a third embodiment of the present invention. 
     The electrodeless lighting apparatus according to the third embodiment of the present invention comprises: a high voltage generator  20  for generating high voltage in a case  10 ; a magnetron  30  for generating microwave by being transmitted the high voltage from the high voltage generator  20 ; and a waveguide  40  for guiding the microwave generated in the magnetron  30 . 
     Also, a bulb motor  90  and a bulb shaft  91  for rotating the bulb  60 , a cooling fan  100  and a fan motor  101  for cooling down inner components, and an air guide  110  are included in the case  10 . 
     In addition, a mesh screen  50  of mesh structure so as to block the microwave and pass the light formed on an outlet portion of the waveguide  40 , and a bulb  60  for generating the light by the microwave in the mesh screen are installed on a front side of the case  10 . 
     Especially, a globe  150  according to the third embodiment of the present invention includes a plurality of fine protrusions (E) formed on an outer surface of the globe  150 , unlike the above first and second embodiments. 
     The globe  150  of spherical shape comprises a permeation portion  151  through which the light generated in the bulb  60  permeates to outer side by forming fine protrusions (E) on the outer surface of the globe  150 , and a mounting portion  152  extended from the permeation portion  151  and coupled to the case  10 . 
     Herein, the mounting portion  152  is constructed as same as the mounting portion of the first embodiment. 
     In addition, the fine protrusions (E) formed on the permeation portion  151  are formed to be protruded as a pentahedron on a crossed areas of vertical corrugations (L) and horizontal corrugations (N), as shown in FIG.  7 . 
     Herein, the vertical corrugations (L) are formed with a predetermined distance therebetween making a vertical shaft, which connects a point (a) on the side where the bulb  60  locates and a point (a′) facing the point (a), a standard. In addition, the horizontal corrugations (N) are formed with a predetermined distance therebetween making a horizontal shaft which has a phase of 90° with the vertical shaft a standard. 
     It is desirable that an apex angle (α) of the fine protrusion of pentahedron shape is 70°˜130°, and a distance between the bases is 5 mm or less. 
     As a modified example of the fine protrusions (E) of pentahedron shape, the fine protrusion may be protruded as a hemisphere shape on the crossed area of the vertical corrugations (L) and the horizontal corrugations (N), as shown in FIG.  8 . 
     It is desirable that the globe is formed using the irregularly reflecting material such as the polymer, the light permeability is 50%˜95%, and the heat resistance temperature is 100° C. or more. 
     FIG. 9 is a cross-sectional view showing principal parts of an electrodeless lighting apparatus according to a fourth embodiment of the present invention. 
     A structure of the electrodeless lighting apparatus according to the fourth embodiment of the present invention is similar to that of the third embodiment, however, the fine protrusions (E′) formed on the globe  160  are successively formed on an inner surface of the globe  160 . 
     The fine protrusion (E′) is formed to have a pentahedron shape having an apex or have a hemisphere shape, as in the third embodiment. 
     Operations and effects of the electrodeless lighting apparatus according to the third and forth embodiments of the present invention will be described as follows. 
     When the microwave generated in the magnetron  30  is transmitted to the mesh screen  50  through the waveguide  40 , then, the plasma is generated in the bulb  60  to emit the light. 
     The light emitted from the bulb  60  passes through the mesh screen  50  having a mesh structure, and then radiated to outer side through the globe  150  or  160 . 
     At that time, the fine protrusions (E or E′) are formed on the globe  150  or  160 , and therefore, these are functioned as irregular reflection by forming various permeance angles when the light passes through the globe  150  or  160 . Therefore, the glaring phenomenon that the user in the lighting area may feel can be reduced. 
     Also, the fine protrusions (E or E′) on the globe  150  or  160  form large entire surface area, and therefore, the heat releasing area is large. Therefore, the heat generated in the globe  150  or  160  during using the lighting apparatus can be released smoothly, and therefore, heating of the bulb  60  and the globe  150  or  160  can be prevented. 
     FIG. 10 is a cross-sectional view showing an electrodeless lighting apparatus according to a fifth embodiment of the present invention, and FIG. 11 is a cross-sectional view showing an operation state of the electrodeless lighting apparatus according to the fifth embodiment of the present invention. 
     The electrodeless lighting apparatus according to the fifth embodiment comprises a high voltage generator  20 , a magnetron  30 , a waveguide  40 , a bulb motor  90  and a bulb shaft  91 , a cooling fan  100  and a fan motor  101 , and an air guide  110  installed in a case  10 , same as the structure of the previously described embodiments. 
     Also, a mesh screen  50  and a bulb  60  are installed in front of the case  10  same as in the previous embodiments. 
     However, according to the fifth embodiment of the present invention, a heat blocking louver  180  for preventing a globe from being heated by the heat generated from the bulb is disposed between the mesh screen  50  and the globe  170 . 
     Herein, the globe  170  comprises a permeation portion  170  having spherical shape, and a mounting portion  172  extended from the permeation portion  171  to be inserted into the outlet portion  41  of the waveguide  40  and coupled to the case  10 . 
     The mounting portion  172  comprises a neck portion  172   a  of cylindrical shape, and a flange portion  172   b  extended from the neck portion  172   a  to radial direction, as shown in FIG.  11 . And the neck portion  172   a  is formed to have an inner diameter which can be apart a certain distance from the outlet portion  41  of the waveguide  40  so that the heat blocking louver  180  can be installed. 
     Referring to FIG. 11, the heat blocking louver  180  comprises a first louver portion  181  of a ring shape fixedly coupled to the case  10  for blocking the heat by interrupting between the mesh screen  50  and the globe  170 ; a second louver portion  183  of a ring shape for blocking the heat by interrupting between the mesh screen  50  and the globe  170  at a position apart from the first louver portion  181 ; and a connecting portion  182  for connecting the first louver portion  181  and the second louver portion  183 . 
     The first louver portion  181  is located between the inside of the neck portion  172   a  in the globe  170  and a periphery of the mesh screen  50 , and the second louver portion  183  is located on a position on a straight line which connects the bulb  60  and the neck portion  172   a  of the globe  170 . 
     In addition, the connecting portions  182  is formed as a bar having both ends connected to the first louver portion  181  and to the second louver portion  183  so as to connect the first louver portion  181  and the second louver portion  183  with a predetermined distance therebetween. 
     Herein, the first louver portion  181  and the second louver portion  183  comprise horizontal portions  181   a  and  183   a  formed in vertical direction for the length direction of the mesh screen  50 , vertical portions  181   b  and  183   b  bent from the horizontal portions  181   a  and  183   a  and extended toward the length direction of the mesh screen  50 , and slant portions  181   c  and  183   c  extended from the vertical portions  181   b  and  183   b  to be slant toward the direction of widening. 
     In addition, both ends of the connecting portion  182  are coupled to the horizontal portion  181   a  of the first louver portion  181  and to the horizontal portion  183   a  of the second louver portion  183 . 
     The heat blocking louver  180  has two louver portions in the description above, however, one, two, or more louver portions may be formed according to the conditions. 
     Operation and effect of the electrodeless lighting apparatus according to the fifth embodiment of the present invention will be described as follows. 
     When the lighting apparatus is operated, the heat of high temperature is generated during the light emitting process by the bulb  60 . 
     The heat generated in the bulb  60  as described above is blocked by the heat blocking louver  180 , and thereby the intensive heating on the globe  170  near the bulb  60  can be prevented. 
     That is, the bulb  60  is located right over the neck portions  172   a  of the globe due to structural and functional reasons. Therefore, the heat generated when the bulb  60  emits the light is concentrated on the neck portions  172   a  of the globe  170  near the bulb  60  and on the permeation portion  171  connected to the neck portion  172   a.    
     At that time, the heat transmitted to the neck portion  172   a  of the globe  170  and to the permeation portion  171  near the neck portion  172   a  is reflected by the first louver portion  181  constituting the heat blocking louver  180 , and then, the heat is induced to the permeation portion  171  of the globe which is far from the bulb  60 . Thereby, a distortion or a breakdown of the globe  170  near the bulb  60  by being heated intensively can be prevented. 
     In addition, the second louver portion  183  constituting the heat blocking louver  180  reflects forward the light energy and the heat energy which passed through the mesh screen, and guides the heat blocked by the first louver portion  181  to the front side. 
     Consequently, the heat blocking louver  180  blocks the heat of high temperature generated from the bulb  60 , and thereby prevents the globe from being distorted or damaged. 
     As described above, according to the electrodeless lighting apparatus of the present invention, the globe is installed around the bulb instead of the reflector and the light guide, and thereby, the structure of the lighting apparatus can be made simply and the omnidirectional lighting can be performed. 
     Also, according to the electrodeless lighting apparatus of the present invention, the irregular reflection is made when the light emitted from the bulb is passed through the globe, and thereby, the glaring phenomenon is prevented and a comfortable lighting environment can be made. 
     Also, according to the electrodeless lighting apparatus of the present invention, the fine protrusions are formed on an inner or outer surface of the globe for enlarging the surface area of the globe, and thereby, the light can be reflected irregularly and the heat releasing function is improved. Therefore, the life span of the product can be increased and the reliability of the apparatus can be improved. 
     Also, according to the electrodeless lighting apparatus of the present invention, the heat blocking louver is installed between the globe and the bulb, and thereby the distortion or breakdown of the neck portions on the globe by the heat generated from the bulb can be prevented. And therefore, the reliability of the apparatus can be improved. 
     As the present invention may be embodied in several forms without departing from the spirit or essential characteristics thereof, it should also be understood that the above-described embodiments are not limited by any of the details of the foregoing description, unless otherwise specified, but rather should be construed broadly within its spirit and scope as defined in the appended claims, and therefore all changes and modifications that fall within the metes and bounds of the claims, or equivalence of such metes and bounds are therefore intended to be embraced by the appended claims.