Abstract:
An illumination device includes a lamp housing component, a main bone disposed inside the lamp housing component, and at least one light emitting component. The light emitting component has a heat sink member and a light emitting member. The heat sink member is locked on the main bone, and the light emitting member is disposed on the lamp housing component and contacts the heat sink member. According to the demand for luminance, the number of light emitting components is optionally increased or decreased on the main bone, or the main bone inside the lamp housing component is replaced by an extended main bone, so as to increase the number of light emitting components.

Description:
BACKGROUND OF THE INVENTION 
     1. Field of Invention 
     The present invention relates to an illumination device, and more particularly to an illumination device having an expandable structure, which has desirable heat dissipation effects and is easily maintained. 
     2. Related Art 
     Currently, a light emitting diode (LED) has already been used on a road lamp for illumination. The LED has advantages of a low power consumption, high luminance, and long lifetime, and thus can solve the problems such as a high power consumption and short lifetime of a conventional mercury road lamp. However, when the LED is applied to the road lamp, the problem of poor heat dissipation still occurs, and the high-temperature heat source generated by the LED causes the heats to be accumulated inside the lamp. As a result, the circuit substrates or electronic devices are damaged due to being overheated. 
     Therefore, a heat dissipation device is needed to divert the high-temperature heat source generated by the LED out of the lamp, so as to entirely reduce the high-temperature heat energy accumulated inside the lamp, and thus, the LED can operate to emit lights normally at a low temperature. A commonly adopted technical means is to utilize the forced convection principle of an auxiliary fan to generate forced heat exchange convection inside the lamp. The forced heat dissipation by using the auxiliary fan requires opening ventilation holes, so as to realize the purpose of rapid heat dissipation. However, the lifetime of the fan is shortened if it is operated under various severe climatic conditions, such that the cost of the lamp is increased. Moreover, the maintenance and replacement of the fan inside the lamp are rather inconvenient. 
     Furthermore, in the conventional heat dissipation manner, a heat-sink lamp housing having heat sink fins is manufactured by die casting molding, and the elements such as an LED and the heat-sink lamp housing are enabled to contact each other. Thus, after the heat-sink lamp housing absorbs the heat energy generated by the LED, a natural convection is directly formed by the exposed heat sink fins of the heat-sink lamp housing with the outside air, thereby dissipating the heat energy via the heat sink fins. In such a heat dissipation manner by using the housing, since the heat sink fins are exposed outside the heat-sink lamp housing, the problem of dust accumulation or bird nesting easily occurs, thereby influencing the heat dissipation effect of the natural convection and greatly reducing the heat dissipation effect of the road lamp. 
     However, in order to increase the heat dissipation area without compromising the structural strength, the heat-sink lamp housing formed through die casting is likely to have defects of an increased weight, restricted form, and difficulties in die sinking. On the other hand, considering the designing flexibility of products, the heat-sink lamp housing formed through die casting has a fixed structure. With such a structural design, the number of light emitting components inside the lamp cannot be increased timely depending upon the demand for the luminance of the lamp, such that the problem of lacking expandability still exists. Consequently, in order to enhance the luminance of the lamp in the heat-sink lamp housing formed through die casting, the entire set of light emitting components inside the lamp unavoidably needs to be replaced. 
     Therefore, how to effectively improve the air convection structure inside the road lamp and the expandable structure of the lamp is urgently researched by relevant manufacturers in this industry. 
     SUMMARY OF THE INVENTION 
     Currently, a road lamp is configured with a heat-sink lamp housing manufactured by die casting, which has a high material cost and a high manufacturing cost. The light emitting components (for example, LED elements) are directly locked on the heat-sink lamp housing, and cannot be easily disassembled and assembled during maintenance. In addition, the heat-sink lamp housing is a main supporting architecture of the entire lamp, which increases the entire weight of the lamp while enhancing the strength thereof. Moreover, due to the fixed external structure of the heat-sink lamp housing, the size and form of the heat-sink lamp housing need to be redesigned if the luminance of the lamp is to be enhanced by increasing the number of the light emitting components. 
     In an embodiment of the present invention, an illumination device is provided. The illumination device comprises a lamp housing component, a main bone, and at least one light emitting component. The main bone is disposed inside the lamp housing component. The light emitting component has a heat sink member and a light emitting member. The heat sink member is disposed inside the lamp housing component and is connected to the main bone, and the light emitting member is disposed on the lamp housing component and contacts the heat sink member. 
     In addition, the light emitting member further comprises a circuit board, at least one LED, and a secondary optical member. The circuit board is a low-thermal-resistance metal core printed circuit board (MC-PCB) and contacts the heat sink member. The LED is electrically connected to the circuit board. The secondary optical member is disposed on the circuit board and covers the LED. 
     The efficacy of the present invention is that, according to the demand for luminance, the light emitting components are optionally increased or decreased on the main bone, or the main bone inside the lamp housing component is replaced by an extended main bone, so as to increase the number of the light emitting components. Moreover, if one of the light emitting components fails, the failed light emitting component is directly disassembled from the main bone and a new light emitting component for replacement is directly assembled on the main bone, and thus, the light emitting components can be easily assembled, dissembled, and replaced. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
       The present invention will become more fully understood from the detailed description given herein below for illustration only, and thus is not limitative of the present invention, and wherein: 
         FIG. 1  is a schematic outside view of an embodiment of the present invention; 
         FIG. 2  is a schematic partially exploded view of an embodiment of the present invention; 
         FIG. 3  is a schematic exploded view of an embodiment of the present invention; 
         FIG. 4  is a schematic outside view of a lamp shade erected on a lamp base by using a supporting rod according to an embodiment of the present invention; 
         FIG. 5  is a schematic exploded view of a heat sink member and a light emitting member according to an embodiment of the present invention; 
         FIG. 6  is a schematic assembled view of the heat sink member and the light emitting member according to an embodiment of the present invention; 
         FIG. 7  is a schematic outside view of an embodiment of the present invention, as seen from another viewing angle; 
         FIG. 8  is a schematic view of flowing motions of an air flow according to an embodiment of the present invention; 
         FIG. 9  is a schematic outside view of another embodiment of the present invention; and 
         FIG. 10  is a schematic view of flowing motions of an air flow according to another embodiment of the present invention. 
     
    
    
     DETAILED DESCRIPTION OF THE INVENTION 
     To make the objectives, structures, features, and functions of the present invention more comprehensible, the present invention is illustrated below in detail through the embodiments. 
       FIG. 1  is a schematic outside view of an embodiment of the present invention,  FIG. 2  is a schematic partially exploded view of an embodiment of the present invention, and  FIG. 3  is a schematic exploded view of an embodiment of the present invention. As shown in  FIGS. 1 ,  2 , and  3 , an illumination device disclosed in the present invention substantially comprises a lamp housing component and a light emitting component. 
     The lamp housing component has a lamp base  10  and a lamp shade  20 . The lamp base  10  comprises a case  11 , a main bone  12 , and two side plates  13  and  14 . The case  11  has a bottom surface  111  (as shown in  FIG. 7 ) and is opened with at least one accommodation hole  113  and a plurality of first air-inlet holes  114 . The accommodation holes  113  are provided for assembling and positioning light emitting members  40 . The accommodation holes  113  may be opened in the bottom surface  111 , and the plurality of first air-inlet holes  114  is adjacent to side edges of the accommodation holes  113 . 
     The main bone  12  has a sleeve  121 , a rod  122 , and at least one reinforcing member  123 . The sleeve  121  is disposed at one end of the main bone  12  and has a slot  1211 . The rod  122  is disposed at the other end of the main bone  12  and is joined to the sleeve  121 , which is provided for locking and positioning heat sink members  30 . One end of the reinforcing member  123  is locked on the rod  122 , and the other end thereof is locked on the case  11 . It should be particularly noted that, the accommodation holes  113  are respectively disposed at left and right sides of the main bone  12 , and the heat sink members  30  are assembled on the rod  122  of the main bone  12  after the heat sink members  30  and the light emitting members  40  are installed in the accommodation holes  113 . With such a structural design, if the light emitting luminance of the illumination device needs to be enhanced, only an extended main bone  12  and a case  11  with more accommodation holes  113  are required for replacement, so as to install more light emitting components (i.e., heat sink members  30  and light emitting members  40 ), such that the illumination device has the light source expandability. 
     Moreover, the two side plates  13  and  14  are respectively disposed at two opposite sides of the case  11 . A plurality of second air-inlet holes  131  and an insertion hole  132  are opened in a surface of the first side plate  13 , and a plurality of second air-outlet holes  141  is opened in a surface of the second side plate  14 . 
     The lamp shade  20  is disposed on the lamp base  10  and forms an accommodation space with the case  11 , the first side plate  13 , and the second side plate  14 . The lamp shade  20  comprises a plurality of first air-outlet holes  21 . The structural configuration of the first air-outlet holes  21  is substantially described as follows. A plurality of grooves  23  is recessed in a surface  22  of the lamp shade  20 , such that the grooves  23  and the surface  22  of the lamp shade  20  form stepped structures, and the stepped structures are formed into the first air-outlet holes  21 . 
     During the assembly of the lamp base  10  and the lamp shade  20 , firstly, the two side plates  13  and  14  are respectively soldered at two opposite sides of the case  11 , and then the sleeve  121  of the main bone  12  is locked on the first side plate  13 , such that the insertion hole  132  of the first side plate  13  is corresponding to the slot  1211  of the sleeve  121 . In addition, the sleeve  121  further comprises a first shaft portion  1212 , the lamp shade  20  similarly comprises a second shaft portion  24 , and an axial rod  25  passes through the first shaft portion  1212  and the second shaft portion  24 , such that the lamp base  10  and the lamp shade  20  are pivotally connected to each other. In this way, the lamp shade  20  is pivotally movable with respect to the lamp base  10 . 
     The lamp base  10  further receives a power supply component  50 , and the power supply component  50  may comprise a power supply, a power supply transformer, or other electronic control circuits (as shown in  FIG. 3 ). 
     In addition,  FIG. 4  is a schematic outside view of a lamp shade erected on a lamp base by using a supporting rod according to an embodiment of the present invention. As shown in  FIG. 4 , the lamp shade  20  further comprises a supporting rod  26  and has an accommodation groove  221  opened in the surface  22  (as shown in  FIG. 2 ). The supporting rod  26  is pivotally mounted at one side edge of the lamp shade  20  and is pivotally moved between a receiving position where the supporting rod  26  is received in the accommodation groove  221  and an upright position where the lamp shade  20  is erected on the lamp base  10 . In the receiving position, the supporting rod  26  is received in the accommodation groove  221  and is snapped to the second side plate  14  (as shown in  FIG. 1 ). In the upright position, the supporting rod  26  rotates for over 180 degrees at the side edge of the lamp shade  20  and opens the lamp shade  20  to erect the lamp shade  20  on the lamp base  10  (as shown in  FIG. 4 ), so as to facilitate the maintenance and replacement of the components inside the lamp base  10 . 
     It should be particularly noted that, since the heat sink members  30  and the light emitting members  40  are assembled together as modular structures, when one of the light emitting members  40  fails or is damaged, only the corresponding heat sink member  30  needs to be individually dissembled from the rod  122  and the damaged light emitting member  40  needs to be taken out for maintenance, or the light emitting component is directly replaced by another new light emitting component (i.e., a heat sink member  30  and a light emitting member  40 ). In the actual application, the entire set of lamp does not need to be dissembled and replaced completely, such that the lamp can be rapidly and conveniently assembled and dissembled in the assembly or the future maintenance. 
     In addition, the light emitting components (i.e., the heat sink members  30  and the light emitting members  40 ) are locked at two opposite sides of the main bone  12  in a left-right symmetrical manner, which thus have desirable light distribution characteristics. Moreover, with the structural design of disposing the plurality of light emitting components at the two opposite sides of the main bone  12 , the light emitting components are respectively corresponding to the plurality of first air-inlet holes  114 , and the plurality of first air-inlet holes  114  respectively guides an air flow to blow the corresponding light emitting components, such that each light emitting component effectively enjoys the heat dissipation effects realized in a manner of heat exchange, thereby achieving a desirable flow field design. 
     Moreover,  FIG. 5  is a schematic exploded view of a heat sink member and a light emitting member according to an embodiment of the present invention,  FIG. 6  is a schematic assembled view of the heat sink member and the light emitting member according to an embodiment of the present invention, and  FIG. 7  is a schematic outside view of an embodiment of the present invention, as seen from another viewing angle. 
     As shown in  FIGS. 5 to 7 , the light emitting component has a heat sink member  30  and a light emitting member  40 . The heat sink member  30  further comprises a contact portion  31  and a heat sink portion  32 . The heat sink portion  32  is disposed on the contact portion  31  in a form of a plurality of fins, in which an air flow channel is formed among the fins. The light emitting member  40  comprises a circuit board  41 , an LED  42 , and a secondary optical member  43 . The circuit board  41  is low-thermal-resistance MC-PCB, at least one LED  42  is electrically connected to the circuit board  41 , and the secondary optical member  43  is disposed on the circuit board  41  and covers the LED  42 . 
     Then, the heat sink member  30  and the light emitting member  40  are assembled together, such that the contact portion  31  of the heat sink member  30  is attached to the circuit board  41  of the light emitting member  40 . When the LED  42  works, the heat energy generated by the LED  42  is transferred from the circuit board  41  to the contact portion  31  and then uniformly conducted to the heat sink portion  32  by the contact portion  31 . Afterwards, the assembled heat sink member  30  and light emitting member  40  are disposed in the accommodation hole  113  of the lamp base  10 , and then at least one locking element  33  passes through at least one locking hole  321  of the heat sink portion  32  and is locked in a corresponding locking hole  1221  on the rod  122 , such that the heat sink member  30  is fixed on the rod  122 . In addition, at least one fixing member  15  is further disposed on the lamp base  10  and erected at a side edge of the accommodation hole  113 . After being locked on the rod  122 , the heat sink member  30  is further securely positioned on the lamp base  10  by using the fixing member  15 , in which the fixing member  15  is connected to the other side edge of the heat sink portion  32  in a locking manner or a snapping manner. 
     It should be particularly noted that, after the heat sink members  30  and the light emitting members  40  are assembled in the accommodation holes  113 , a set of first air-inlet holes  114  may be opened adjacent to each accommodation hole  113 . In other words, a set of first air-inlet holes  114  is provided at one side edge of each heat sink member  30  in a one-to-one corresponding manner (as shown in  FIG. 3 ). In this way, after entering via each set of first air-inlet holes  114 , an outside cold air flow performs a heat exchange convection for each heat sink member  30 , such that each heat sink member  30  is blown by the cold air flow to remove the heat energy and each heat sink member  30  is subjected to the same heat dissipation condition. Thus, a uniform temperature status is maintained in the accommodation space, so as to prevent the heat energy from being accumulated at a certain specific position of the lamp base  10 . 
     Moreover,  FIG. 8  is a schematic view of flowing motions of an air flow according to an embodiment of the present invention. As shown in  FIG. 8 , a lamp rod  60  is inserted into the slot  1211  of the sleeve  121  through the insertion hole  132  of the first side plate  13 , and then the lamp rod  60  is clamped and fixed towards the slot  1211  by a clamper  124  (as shown in  FIGS. 3 and 8 ), such that the lamp housing component forms an inclined illumination angle. When a plurality of LEDs  42  emits lights, the light source may be diffused uniformly by the secondary optical members  43 , and the secondary optical members  43  of the light emitting members  40  have the same lighting pattern. Once the circuit board  41  absorbs the high-temperature heat energy generated by the LED  42 , the contact portion  31  rapidly absorbs the high-temperature heat energy due to the close attachment between the contact portion  31  of the heat sink member  30  and the circuit board  41 , and then uniformly conducts the heat energy to the heat sink portion  32 . In this way, the heat energy is uniformly diffused to any position of the heat sink portion  32  and a heat collecting area is formed in the accommodation space between the lamp base  10  and the lamp shade  20 . 
     In other words, the heat collecting area is full of hot air flow, and the volume of the hot air flow is expanded and the density thereof is reduced, such that a temperature difference is generated between the temperatures inside and outside the lamp housing component. Due to the temperature difference, the air flows inside and outside the lamp housing component have different densities, so that the hot air flow gradually rises and is discharged from the first air-outlet holes  21  or the second air-outlet holes  141 , and meanwhile the cold air flow enters the lamp base  10  for supplement from the first air-inlet holes  114  or the second air-inlet holes  131  and removes the heat energy on the heat sink portion  32  once again, and so forth. Thus, the heat energy of the heat sink members  30  is transmitted out of the lamp housing component through the air flows, so as to form a cyclic natural convection cooling. 
       FIG. 9  is a schematic outside view of another embodiment of the present invention, and  FIG. 10  is a schematic view of flowing motions of an air flow according to another embodiment of the present invention. The specific implementation in this embodiment is substantially the same as that of the above embodiment, and only the difference there-between is illustrated below. In this embodiment, a plurality of first air-inlet holes  114  is opened in the lamp base  10  and a plurality of first air-outlet holes  21  is opened in the lamp shade  20 , without opening air-inlet holes or air-out holes in the first side plate  13  and the second side plate  14 , such that the hot air flow is discharged out of the lamp housing component from the plurality of first air-outlet holes  21 , and the cold air flow enters the lamp housing component from the plurality of first air-inlet holes  114 , so as to form a single cyclic heat exchange convection.