Abstract:
A surge discharging device for releasing electric surge due to high voltage so as to avoid destroy of an electric apparatus having the device, the surge discharging device comprises a body having a hollow space; a channel connected between the hollow space and an exterior of the body; two terminals spaced at two sides of the hollow space; front ends of the terminals being exposed in the hollow space and rear ends of the terminals being exposed out of the body. The body includes a first enclosure and a second enclosure. A plurality of connecting bars are extended from the first enclosure; and the second enclosure is formed with a plurality of connecting holes. An inner wall of each of the first enclosure and the second enclosure has a recess; as the first enclosure and the second enclosure are combined, the two recesses are formed as the hollow space.

Description:
FIELD OF THE INVENTION 
   The present invention relates to surges, and particularly to a surge discharging device, in that, no varistor is used. Furthermore the surge discharging device has a smaller size and has a standard specification so that it can be used to various electric devices. Furthermore a hollow space and electrodes of the surge discharging device are allowed to be changed within the allowable margin of the specification so as to match the requirements of the applications. 
   BACKGROUND OF THE INVENTION 
   For reducing the component size of the electronic device, semiconductors have become the main components for the processors and controller in the electronic devices so as to reduce the size of the electronic devices and the functions of the devices are promoted greatly. However, these kinds of components are weak in the preventing of surge waves generated in the circuit. Thus it is important to prevent the destroy from surge waves in the electronic devices. Generally, there are two conditions which will induce surges in the circuit. One is switching surges due to the switching of the electric power switching. The other is from the nature phenomenon, such as lighting surges due to the thunderbolt to buildings. However all these surges will affect the operation of the electric device indoors, even the device will be destroyed or induce fire accident. 
   Generally, in electric devices or power system, fuse or fuseless switch are used as short circuit protection for transient high voltage or overload. However the reaction times of generally electric elements are about 2 ms, while the reaction time of the surge is several micro seconds (μs) which are very shorter than the transient reaction time of the electric elements. Thus, the fuse or fuseless switch is not enough for preventing the destroy from surges. 
   The prior art principle for the surge discharging device is by using a kernel element, varistor. The resistance of the varistor is changeable based on the voltage difference between two ends of the elements. The technologies are disclosed in Taiwan Patent No. M297037. Besides, in Taiwan Patent Publication No. 200623573, at lease one semiconductor field emission over-voltage protection device is disclosed. A semiconductor field emission over-voltage protection device is forwardly connected in parallel or forwardly connected with anti-parity. The protection device is also coupled to a front end of an I/O of a high frequency circuit, or is connected between an input end and a ground end. Above mentioned applications used in the normal voltage. The resistance of the varistor is very high. When the voltage has achieved to a predetermined value, the resistance will decrease rapidly with a react time of about several nano-second (ns). Thus, when a varistor is used to a surge discharging device, the surge discharging device is connected in parallel to a front end of an electric device. As a result, in normal operation voltage, the surge discharging device is used as in open circuit. When the voltage increases abnormally, it is used as in short circuit for prevent high energy from flowing into the electric device so that the surge has no effect to the electric device. 
   SUMMARY OF THE INVENTION 
   Accordingly, the primary object of the present invention is to provide a surge discharging device, in that, no varistor is used. Furthermore the surge discharging device has a smaller size and has a standard specification so that it can be used to various electric devices. Thereby a hollow space and electrodes of the surge discharging device are allowed to be changed within the allowable margin of the specification so as to match the requirements of the applications. 
   Effect of the present invention is that the manufacturing work is simple and no parallel connected varistor is used. When voltage increases in several nanoseconds abnormally, a hollow space is used to generate charges by discharge electrodes. The charges are drained out from a channel so as to protect the circuit from thunderbolt, electric static charges, and surges. 
   To achieve above objects, the present invention provides a surge discharging device for releasing electric surge due to high voltage of a circuit so as to avoid destroy of an electric apparatus having the device, the surge discharging device comprising a body having a hollow space; a channel connected between the hollow space and an exterior of the body; two terminals spaced at two sides of the hollow space; front ends of the terminals being exposed in the hollow space and rear ends of the terminals being exposed out of the body. The body includes a first enclosure and a second enclosure; a plurality of connecting bars are extended from the first enclosure; and the second enclosure is formed with a plurality of connecting holes. An inner wall of each of the first enclosure and the second enclosure has a recess; as the first enclosure and the second enclosure are combined, the two recesses are formed as the hollow space. The hollow space has a rectangular shape or an elliptical shape. Each of the front ends is a rectangular discharging end, or a cambered discharging end or a tip discharging end. 
   The various objects and advantages of the present invention will be more readily understood from the following detailed description when read in conjunction with the appended drawing. 

   
     BRIEF DESCRIPTION OF THE DRAWINGS 
       FIG. 1  is an exploded perspective view of the surge discharging device of the present invention. 
       FIG. 2  is an assembled perspective view of the surge discharging device of the present invention. 
       FIG. 2A  shows the cross sectional view of the surge discharging device of the present invention. 
       FIG. 3  is a schematic view showing that the surge discharging device of the present invention is applied to a circuit. 
       FIG. 4  shows another embodiment of the present invention. 
       FIG. 4A  is an assembled perspective view of a further embodiment of the present invention. 
       FIG. 4B  shows the application of  FIG. 4A . 
       FIG. 5  shows a yet embodiment of the present invention. 
       FIG. 6  shows a variation of the present invention, wherein the front ends of the terminals are changed. 
       FIG. 7  is a schematic view showing another embodiment of the front ends of the terminals of the present invention. 
       FIG. 8  is a schematic view showing a further embodiment of the front ends of the terminals of the present invention. 
       FIG. 9  is a schematic view showing a yet embodiment of the front ends of the terminals of the present invention. 
   

   DETAILED DESCRIPTION OF THE INVENTION 
   In order that those skilled in the art can further understand the present invention, a description will be provided in the following in details. However, these descriptions and the appended drawings are only used to cause those skilled in the art to understand the objects, features, and characteristics of the present invention, but not to be used to confine the scope and spirit of the present invention defined in the appended claims. 
   Referring to  FIG. 1 , the surge discharging device of the present invention is illustrated. In this embodiment, the present invention has the following elements. 
   A first enclosure  11  is extended with at least one connecting bar  111 . The first enclosure  11  has a wall  112 . A recess  113  is formed in the wall  112 . 
   A second enclosure  12  has at least one connecting hole  121  corresponding to the connecting bar  111 . In this embodiment, there are four connecting bars  111  and four connecting holes  121 . The second enclosure  12  has a wall  122 . A recess  123  is formed in the wall  122 . A hollow space  13  is formed by the recess  113  and recess  123  as the first enclosure  11  is combined with the second enclosure  12  (referring to  FIG. 2A ). There are various shapes suitable for the hollow space  13 , preferably, the hollow space  13  has a round shape or a rectangular shape which is based on the rule of electric safety. It will be described hereinafter. 
   Referring to  FIG. 2 , when the first enclosure  11  and second enclosure  12  are combined, a channel  14  is formed between the first enclosure  11  and the second enclosure  12 . The channel  14  causes that the hollow space  13  can communicate with exterior through the channel  14 . 
   Each of the two terminals  15 ,  16  has a part embedded in the first enclosure  11  and the other part extends downwards to be out of the first enclosure  11 . Two tip ends of the front ends  151 ,  161  of the terminals  15 ,  16  are arranged at two sides of the hollow space  13  and are faced to one another. The hollow space  13  and channel  14  are formed as a discharging path for protecting a circuit from thunderbolt or electrostatic effect. 
     FIG. 2  shows the assembly view of the elements in  FIG. 1 . Thus the surge discharging device is formed as a small electric part. The terminals  15 ,  16  serve for being installed to a circuit substrate  3  (referring to  FIG. 2 ) of such as a transformer, or a charging base of a handset. 
   In the present invention, the surge discharging device is used to a circuit substrate for preventing surges. To enhance the protection of the electric device, the present invention is suitable to be installed to a primary end or secondary end of a transformer of a power input end.  FIG. 3  shows that a circuit substrate of a transformer is installed with two surge discharging devices at the primary end and secondary end. In the safety rule, if the voltage in the primary end is 110V, at the primary end, the distance between the two terminals are 1.5 mm. At the secondary end, the distance between the two terminals are 2.0 mm. If the voltage in the primary end is 200V, at the primary end, the distance between the two terminals are 2.0 mm. At the secondary end, the distance between the two terminals is 4.0 mm. 
     FIG. 4  shows another embodiment of the present invention, similarly, 
   A first enclosure  21  is extended with at least one connecting bar  211 . The first enclosure  21  has a wall. A recess is formed in the wall. 
   A second enclosure  22  has at least one connecting hole  221  corresponding to the connecting bar  211 . In this embodiment, there are four connecting bars  211  and four connecting holes  221 . The second enclosure  22  has a wall. A recess  23  is formed in the wall. A hollow space is formed by the recesses of the first enclosure  21  and the second enclosure  22  as the first enclosure  21  is combined with the second enclosure  22 . There are various shapes suitable for the hollow space, preferably, the hollow space  13  has a round shape or a rectangular shape which is based on the rule of electric safety. It will be described hereinafter. 
   A channel  24  is formed in the lower side of the second enclosure  12 . The channel  24  causes that the hollow space can communicate with exterior through the channel  24 . 
   Each of the two terminals  25 ,  26  has a part embedded in the second enclosure  22  and the other part extends out of the second enclosure  22 . Two upper ends of the terminals  25 ,  26  are arranged at two sides of the hollow space  13  and are faced outwards. The hollow space  23  and channel  24  are formed as a discharging path.  FIG. 4A  shows the assembly of the first enclosure  21  and the second enclosure  22  and  4 B shows that the present invention is used to a circuit substrate. 
     FIG. 5  shows a further embodiment of the present invention. In this embodiment, those identical to the first embodiment will not be further described herein. Only those different from above embodiment are described. In this embodiment, the front ends  151 ,  161  of the terminals  15 ,  16  are bent so as to have a preferred positioning to the first enclosure  11  and second enclosure  12 . 
   The principle of the present invention will be described herein. In a strong electric field, a surface with a great curvature, such as a tip end or an apex of a small object, has greater electric field, as a result, the air nearby will be ionized so as to discharge, this is so called corona discharge. Thus, as the surge discharging device of the present invention is applied to a circuit substrate, when a surge generates, charges accumulated in the circuit board will discharge with the front ends of the terminals and thus flow through the hollow space and channel. 
   Some embodiments of the present invention will be described hereinafter with reference to the appended drawings. 
   Referring to  FIG. 6 , in this embodiment, those identical to the first embodiment will not be further described herein. Only those different from above embodiment are described. In  FIG. 6 , it is illustrated that the front ends  151 ,  161  of the terminals  15 ,  16  are bended from other portion and have a rectangular shape. The distance between the two terminals  15 ,  16  serve to control the voltage in discharging so as to be worked in different working mode. Thus each of the terminals  15 ,  16  has four tip edges at the front end so that more electrons can be discharged as surges occur. As a surge occurs, the air is ionized into positive ions and negative ions in the hollow space  13  and especially the space between the two terminals  15 ,  16  (which are now as electrodes). The insulating strength of the body  1  is very stronger than that of the air so that the ionized particles will form a discharging path through the hollow space  13  and the channel  14 . Thus the high voltage and large current induced from the surge will be guided to the ground. 
   Referring to  FIGS. 7 and 9 , another application of the present invention is illustrated. In this embodiment, those identical to the first embodiment will not be further described herein. Only those different from above embodiment are described. In the embodiments illustrated in  FIGS. 7 to 9 , the hollow space  13  is elliptical. In  FIG. 7 , the front ends  151 ,  161  of the terminals  15 ,  16  are bended from other portion and have a rectangular shape. In  FIG. 8 , the front ends  151 ,  161  of the terminals  15 ,  16  are bended from other portion and have a cambered shape. In  FIG. 9 , the front ends  151 ,  161  of the terminals  15 ,  16  are bended from other portion and have a tip shape. The distance between the two terminals  15 ,  16  serve to control the voltage in discharging so as to be worked in different working mode. Thus each of the terminals  15 ,  16  has four tip edges at the front end so that more electrons can be discharged as surges occur. As a surge occurs, the air is ionized into positive ions and negative ions in the hollow space  13  and especially the space between the two terminals  15 ,  16  (which are now as electrodes). The insulating strength of the body  1  is very stronger than that of the air so that the ionized particles will form a discharging path through the hollow space  13  and the channel  14 . Thus the high voltage and large current induced from the surge will be guided to the ground. 
   In above embodiments, it is illustrated that the hollow space  13  may have a rectangular shape or an elliptical shape. Thereby the front ends  151 ,  161  of the terminals  15 ,  16  may be rectangular, cambered or tipped. However the main feature of the present invention is that the front ends  151 ,  161  of the terminals  15 ,  16  can induce the tip discharge so that air is ionized and thus the current is drained out through the hollow space  13 , the channel  14  and to the exterior of the body  1 . Thus the high voltage and current can be guided to the ground. 
   The present invention is thus described, it will be obvious that the same may be varied in many ways. Such variations are not to be regarded as a departure from the spirit and scope of the present invention, and all such modifications as would be obvious to one skilled in the art are intended to be included within the scope of the following claims.