You are an expert at summarizing long articles. Proceed to summarize the following text:

You are an expert at summarizing long articles. Proceed to summarize the following text: 
FIELD OF THE INVENTION 
     The present invention relates generally to a roadblock, and more particularly to a light-emitting device for use in covering a conic roadblock in such a way that the light-emmiting device can be removed from the conic roadblock which is not in use. 
     BACKGROUND OF THE INVENTION 
     As shown in FIG. 1, a conic roadblock  10  of the prior art is provided in the outer surface with a coating of fluorescence capable of producing light while it is being acted upon by radiant energy. The prior art conic roadblock  10  is defective in design in that its warning effect is easily undermined by a poor visibility at night or in an inclement weather. 
     SUMMARY OF THE INVENTION 
     The primary objective of the present invention is to provide a light-emitting device which is designed for use along with a conic roadblock. 
     In keeping with the principle of the present invention, the foregoing objective of the present invention is attained by the light-emitting device comprising a conic body of a fabric material, a plurality of light-emitting elements, a battery bag, and a battery box. The conic body is formed of two fabric layers and is removably fitted over a conic roadblock. The light-emitting elements are sandwiched between the two fabric layers of the conic body and are connected with a power core line of the battery box. The battery bag is fastened with the conic body for containing the battery box. 
     The conic body is provided with a poll ring to facilitate the removing of the light-emitting device of the present invention from the conic roadblock which is no longer in use. 
     The conic body of the light-emitting device of the present invention is made of a soft material, such as a waterproof canvas, or polyvinyl chloride (PVC). The light-emitting device of the present invention can be thus folded to facilitate the storage of the device while not in use. 
     The conic body of the light-emitting device of the present invention is provided with a zipper extending from the base to the vertex of the conic body. The conic body can be therefore spread out by opening the zipper. 
     The features, the functions, and the advantages of the present invention will be more readily understood upon a thoughtful deliberation of the following detailed description of the present invention with reference to the accompanying drawings. 
    
    
     BRIEF DESCRIPTION OF THE DRAWINGS 
     FIG. 1 is a schematic view of a roadblock of the prior art. 
     FIG. 1A is a schematic view of a plurality of the prior art roadblocks which are stacked together. 
     FIG. 2 is a perspective view of the present invention. 
     FIG. 3 shows a sectional view of the present invention. 
     FIG. 4 is a sectional view of a warning unit of the present invention. 
     FIG. 5A is an exploded view of the warning unit of the present invention. 
     FIG. 5B is a schematic view of a circuit board of the present invention. 
     FIG. 6 is a schematic view of a flattened device of the present invention. 
     FIG. 7 is a schematic view of the present invention being fitted over a conic roadblock. 
     FIG. 8 is another schematic view of the present invention being fitted over a conic roadblock. 
     FIG. 9 is a perspective view of a second preferred embodiment of the present invention. 
     FIG. 10 is a sectional schematic view of a warning unit of the second preferred embodiment of the present invention. 
     FIG. 11 is a front view of the second preferred embodiment of the present invention being spread out. 
     FIG. 12 is a rear view of the second preferred embodiment of the present invention being spread out. 
     FIG. 13A is an exploded view of the warning unit of the second preferred embodiment of the present invention. 
     FIG. 13B is a schematic view of the rear side of a circuit board of the second preferred embodiment of the present invention. 
     FIG. 14 is a schematic view of the second preferred embodiment of the present invention being fitted over a conic roadblock. 
     FIG. 15 is another schematic view of the second preferred embodiment of the present invention being fitted over a conic roadblock. 
    
    
     DETAILED DESCRIPTION OF THE INVENTION 
     As shown in FIGS. 2-4, a light-emitting device of the present invention comprises a hollow conic body  20  of a fabric material, and a plurality of warning units  30  fastened to the conic body  20 . The conic body  20  is formed of an inner fabric layer  21  and an outer fabric layer  22 , as shown in FIG.  4 . The inner layer  21  and the outer layer  22  are made of PVC. The inner layer  21  and the outer layer  22  are joined together such that the fringes of the outer layer  22  are attached to the fringes of the inner layer  21 , thereby resulting in formation of a space  23  between the inner layer  21  and the outer layer  22 . The outer layer  22  is provided with a plurality of through holes  221  which are arranged at an interval. The conic body  20  is provided in proximity of vertex with a pull ring  201 , as shown in FIG.  2 . The space  23  is used to dispose a press switch  202  which has a key projection forward the outer layer  22 . 
     Referring to FIG. 3, the inner layer  21  is provided with a battery bag  40  and a battery box  50 . The battery bag  40  has an opening  41 , a magic tape  42 , and an outer cover  43 . The outer cover  43  has a root portion  431  which is fastened with the inner layer  21 . The outer cover  43  has a free end  432 , which covers the opening  41  of the battery bag  40 . The free end  432  is provided with a magic tape  433 . The outer cover  43  is joined securely with the battery bag  40  by the magic tape  433  of the outer cover  43  and the magic tape  42 . The magic tapes  42  and  433  are also known as Velcro tapes which can be pressed together or pulled apart for easy fastening and unfastening. The battery box  50  has a power core line  51  and a poll grip  52 . The power core line  51  is connected to the press switch  202  and the warning units  30 . The battery box  50  serves to provide the warning units  30 . The battery box  50  serves to provide the warning units  30  with power in conjunction with the press switch  202 . The pull grip  52  is located at the top of the battery box  50  out of the battery bag  40 . 
     Referring to FIGS. 4 and 5, the warning units  30  are disposed in the space  23  such that the warning units  30  are corresponding in location to the through holes  221  of the outer layer  22 , and that the warning units  30  are connected with the power core line  51 . The warning units  30  are formed of a light reflecting layer  31 , a waterproof layer  32  pervious to light, a circuit board  33 , a protective jacket  34 , a padded plated  35 , and a light-emitting diode  36 . The light reflection layer  31  is attached to the outer layer  22  and provided with a plurality of through holes  311  corresponding in location to the through holes  221  of the outer layer  22 . The waterproof layer  32  is attached to the light reflecting layer  31  such that the fringe of the waterproof layer  32  is adhered to the edges of the through holes  311  of the light reflecting layer  31 . The circuit board  33  is disposed in the space  23  and is provided with a plurality of wiring holes  331  for putting therethrough the power core line  51 . Located between the opposite wiring holes  331  is a conductive area  332  for conducting the wiring holes  331 . The circuit board  33  is further provided with a plurality of soldering holes  333  for soldering the pins  361  of the light-emitting diode  36 . The soldering holes  333  are provided in the periphery with a plurality of retaining holes  334  for retaining the wedge-shaped ends  342  of the clamps  341  of the protective jacket  34 . 
     Referring to FIGS. 4 and 5A, the protective jacket  34  is provided with at least one padded plate  35 . The protective jacket  34  is provided in the top with a center through hole  343 , and in the bottom with a plurality of clamps  341 , with each having a wedge-shaped end  342 , which is retained in the retaining hole  334  of the circuit board  33  via the through hole  311  of the light reflecting layer  31  and the through hole  211  of the outer layer  22 . As a result, the outer layer  22  and the light reflecting layer  31  are securely retained by the circuit board  33  and the padded plate  35 . The light-emitting diode  36  is inserted into the center through hole  343  of the protective jacket  34  and is provided with two pins  361  which are fastened in the soldering holes  333  of the circuit board  33  by soldering. The soldering holes  333  are located in the conductive area  332  of the circuit board  33 . The power is transmitted from the power core line  51  to the light-emitting diode  36  via the conductive area  332  of the circuit board  33 . 
     Referring to FIGS. 6,  7  and  8 , the present invention is designed for use along with the conventional conic roadblock  10 . In operation, as soon as the press switch  202  is pressed, the power is transmitted from the battery box  50  to the circuit board  33  via the power core line  51 . The power is then made available to the light-emitting diode  36  via the conductive area  332  of the circuit board  33 . The roadblock  10  is thus vividly visible, thanks to the light emitted by the light-emitting diode  36 . When the roadblock  10  is no longer in use, the roadblock  10  can be easily stripped of the present invention by lifting the present invention with finger holding the pull ring  201 . In light of the present invention being made of PVC, the present invention can be easily folded to facilitate the storage of the present invention. 
     Referring to FIGS. 9-12, the second preferred embodiment of the present invention comprise a hollow conic body  20 ′ which is provided with a meshed layer  24 , a plurality of outer fabric layers  25 , and a plurality of light reflecting layers  26 . The outer fabric layer  25  is adhered to the meshed layer  24 , as shown in FIG.  10 . The light reflecting layers  26  are attached to the outer fabric layers  25  such that the fringes of the light reflecting layers  26  are adhered to the fringes of the outer fabric layers  25 , thereby resulting in formation of a receiving space  27  between the outer fabric layers  25  and the light reflecting layers  26 . The light reflecting layers  26  are provided with a plurality of through holes  261  which are arranged at an interval. The conic body  20 ′ is provided with a zipper  28  extending in the direction from the base to the vertex of the conic body  20 ′, as shown in FIG.  9 . As the conic body  20 ′ is unzipped, the conic body  20 ′ can be spread out to have a sectoral shape, as shown in FIGS. 11 and 12. The conic body  20 ′ is provided in proximity of the vertex thereof with an upright pull ring  201 ′. The roadblock  10  is stripped of the conic body  20 ′ with finger holding the pull ring  201 ′. The receiving space  27  serves to house a press switch  202 ′ which has a key projecting toward the light reflecting layers  26 , as shown in FIG.  11 . 
     Referring to FIG. 12 the battery bag  60  and the battery box  70  are disposed on the back side of the meshed layer  24  of the conic body  20 ′. The battery bag  60  has an opening  61 , a magic tape  62 , and an outer cover  63  which is provided at the free end thereof with a magic tape  632 . The opening  61  is covered by the outer cover  63  such that the magic tape  62  is fastened with the magic tape  632  of the outer cover  63 . The battery box  70  is kept in the battery bag  60  and is provided with a power core line  71  and at least one dry battery. The power core line  71  is disposed in the receiving space  27  and is serially connected with the warning units  80 . The illuminating of the warning units  80  is regulated by the press switch  202 ′. 
     Referring to FIGS. 10,  13 A, and  13 B, the warning units  80  are housed in the receiving space  27  such that they are corresponding in location to the through holes  261  of the light reflecting layer  26 . The warning units  80  are formed of a waterproof layer  81  pervious to light, a circuit board  82 , a light-emitting diode (LED)  83 , a protective jacket, and a padded plate  85 . The waterproof layer  81  is attached to the light reflecting layer  26  such that the fringe of the waterproof layer  81  is adhered to the fringes of the through holes  261  of the light reflecting layer  26 . The circuit board  82  is disposed in the receiving space  27  and is provided in two opposite sides thereof with two wiring holes  821 . The circuit board  82  is provided with a conductive area  822  via which the wiring holes  821  are connected. The conductive area  822  is provided with a plurality of soldering holes  823  for fixing the pins  831  of the LED  83 , and a plurality of retaining holes  824  circumventing the soldering holes  823 . The protective jacket  84  is provided with a center through hole  841  and a plurality of clamps  842  which are provided with a wedge-shaped end  843 . The light reflecting layer  23  is held between the circuit board  82  and the padded plate  85 . The wedge-shaped end  843  is retained in the retaining hole  824  via the through hole  261  of the light reflecting layer  23 . The protective jacket  84  is provided with at least one padded plate  85 . The light-emitting diode  83  has two pins  831 . The top of the light-emitting diode  83  is inserted into the center through hole  841  of the protective jacket  84  such that the pins  831  are fixed in the soldering holes  823  of the circuit board  82 . As a result, the pins  831  of the light-emitting diode  83  are connected with the conductive area  822  of the circuit board  82 . 
     Referring to FIGS. 11 and 12, the meshed layers  24  of the conic body  20 ′ are provided with a magic tape  241  and a plurality of round holes  242 . In the event that the zipper  28  is out of order, the magic tapes  241  of the meshed layers  24  may be used. The conic body  20 ′ of the second preferred embodiment of the present invention can be also folded to facilitate the storage of the conic body  20 ′. 
     Referring to FIGS. 7,  8 ,  14 , and  15 , the light reflecting layer  31  may be designed in accordance with the circumstance of the road construction. 
     The power source of the warning units of the present invention may be solar energy, car battery, or and alternating current source. The warning units may be provided with a photosensor by which the warning units are automatically activated in case of a poor visibility or inclement weather.

Summary:
A light-emitting device is designed to cover removably a conic roadblock and is formed of a hollow conic body and a plurality of warning units. The hollow conic body is formed of an outer fabric layer and an inner fabric layer. The warning units are disposed on the outer fabric layer of the conic body. The conic body is fitted over the conic roadblock. The warning units are provided with a light-emitting diode to make the conic roadblock vividly visible to the operator of an approaching motor vehicle.