Abstract:
Disclosed is a circuit breaker. The circuit breaker includes an arc exhaust port for exhausting an arc generated in the inner box; an outer box receiving the inner box and including an arc passage for exhausting the arc from the exhaust port to an outside; and an arc guide part for guiding the arc from the arc exhaust port into the arc passage, wherein the arc guide part includes: an upper guide; a lower guide spaced apart from the upper guide; and a connecting part connecting the upper and lower guides to each other in a longitudinal direction.

Description:
CROSS-REFERENCE TO RELATED APPLICATIONS 
     Pursuant to 35 U.S.C. §119(a), this application claims the benefit of earlier filing date and right of priority to Korean Patent Application No. 10-2012-0079902, filed on Jul. 23, 2012, the contents of which is incorporated by reference herein in its entirety. 
     BACKGROUND 
     The disclosure relates to a circuit breaker. 
     In general, a circuit breaker is a device for maintaining safety by blocking a circuit in an abnormal state such as an overload or a short circuit. That is, when a current exceeding a rated current flows through an electric circuit, the circuit breaker performs a function of blocking the current flow in order to protect a worker. 
     Hereinafter, a circuit breaker will be described with reference to accompanying drawings. 
       FIG. 1  is a perspective view showing a circuit breaker according to the related art. 
     Referring to  FIG. 1 , the circuit breaker  1  includes an upper outer box (refer to reference numeral  20  in  FIG. 2 ) which defines an upper appearance, a lower outer box  10  which defines a lower appearance, and an inner box  30  disposed in the upper and lower outer boxes  20  and  10 . When a user operates a switch lever to control an operation of the circuit breaker  1 , fixed and movable contactors placed in the circuit breaker  1  are separated from each other, so that a high-temperature thermal arc is generated between both contactors. The arc damages an electric conductor and a forming component in the circuit breaker  1 . Therefore, there is a need to rapidly exhaust the arc generated in the circuit breaker  1  to an outside. 
       FIG. 2  is a view showing an exhaust port structure of a load part of a circuit breaker according to the related art. 
     Referring to  FIG. 2 , the exhaust port structure of the load part of the circuit breaker includes an inner box  30 , a load part arc exhaust port  12  connected to the inner box  30 , an arc guide part  14  for guiding a movement of an arc passing through the load part arc exhaust port  12 , and an arc passage forming part  13  for providing an passage through which an arc guided by the arc guide part  14  is exhausted. The acr guide part  14  is inclined upward about a horizontal direction such that the arc guide part  14  may be connected to a load part arc passage  15 . 
     The arc passage forming part  13  includes the load part arc passage  15  for providing an exit and entry passage of an arc and a protrusion part  11  adjacent to the load part arc passage  15 . The protrusion part  11  may include a plurality of inclined parts  11   a  and for example, may have a shape of a trigonal prism. 
     A moving path of the arc generated from the load part of the circuit breaker  1  is as follows. 
     An arc initially generated from the inner box  30  of the circuit breaker  1  passes through the load part arc exhaust port  12  and the arc, which passes through the load part arc exhaust port  12 , passes through the load part arc passage  15  along the arc guide part  14  to be exhausted to an outside of the circuit breaker  1 . 
     However, since the load part arc exhaust port  12  is spaced apart from the load part arc passage  15  and a configuration of continuously guiding the arc exhausted from the load part arc exhaust port  12  into the load part arc passage  15  does not exist, the arc, which passes through the load part arc exhaust port  12 , is not rapidly exhausted to an outside of the circuit breaker  1  so that voltage leakage and reverse current phenomenons occur in the circuit breaker  1 . 
       FIG. 3  is a view showing an arc exhaust structure of a power source part of a circuit breaker according to the related art. 
     Referring to  FIG. 3 , the arc exhaust structure of the circuit breaker includes an inner box  30 , a power source arc exhaust port  25  connected to the inner box  30 , a power source arc passage forming part  22  for guiding a movement of an arc passing through the power source arc exhaust port  25 . 
     The power source arc passage forming part  22  includes a passage guide part  22   a  having a round shape and a passage inclined part  22   b  connected to the passage guide part  22   a  and inclined at a predetermined angle. An arc may be exhausted into an outside of the circuit breaker  1  through a power source arc passage  21  which is an inner space in which the passage guide part  22   a  and the passage inclined part  22   b.    
     A moving path of the arc generated from the power source part of the circuit breaker  1  is as follows 
     An arc initially generated from the inner box  30  of the circuit breaker  1  passes through the power source arc exhaust port  25  and the arc, which passes through the power source arc exhaust port  25 , passes through the power source arc passage  21  to be exhausted into an outside of the circuit breaker  1 . 
     However, since the power source arc exhaust port  25  is spaced apart from the power source arc passage  21  and a configuration of continuously guiding the arc exhausted from the power source arc exhaust port  25  into the power source arc passage  21  does not exist, the arc, which passes through the power source arc exhaust port  25 , is not rapidly exhausted to an outside of the circuit breaker  1 , so that voltage leakage and reverse current phenomenons may occur in the circuit breaker  1 . 
     SUMMARY 
     The embodiment provides a circuit breaker in which an arc generated by operating the circuit breaker is rapidly exhausted so that a residual or leakage arc is minimized in the circuit breaker. 
     According to one embodiment, there is provided a circuit breaker including an inner box including an arc exhaust port for exhausting an arc generated in the inner box; an outer box receiving the inner box and including an arc passage for exhausting the arc from the exhaust port to an outside; and an arc guide part for guiding the arc from the arc exhaust port into the arc passage, wherein the arc guide part includes: an upper guide; a lower guide spaced apart from the upper guide; and a connecting part connecting the upper and lower guides to each other in a longitudinal direction. 
     According to another embodiment, there is provided a circuit breaker including an inner box including an arc exhaust port for exhausting an arc generated in the inner box; an outer box receiving the inner box and including an arc passage for exhausting the arc from the arc exhaust port to an outside; and an arc guide part having one side making contact with the arc exhaust port for guiding the arc from the arc exhaust port into the arc passage, wherein the arc guide part protrudes at a predetermined length from a portion making contact with the arc exhaust port to the arc passage. 
     The details of one or more embodiments are set forth in the accompanying drawings and the description below. Other features will be apparent from the description and drawings, and from the claims. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         FIG. 1  is a view showing a touch window according to the related art. 
         FIG. 2  is a view showing an exhaust port structure of a load part of a circuit breaker according to the related art. 
         FIG. 3  is a view showing an arc exhaust structure of a power source part of a circuit breaker according to the related art. 
         FIG. 4  is a perspective view showing a circuit breaker according to the embodiment. 
         FIG. 5  is a view of the circuit breaker when viewed at the load part of the circuit breaker. 
         FIG. 6  is a view showing the first arc exhaust structure according to an embodiment. 
         FIG. 7  is a perspective view showing the first arc exhaust structure according to an embodiment. 
         FIG. 8  is a perspective view showing a lower guide according to an embodiment. 
         FIG. 9  is a perspective view showing a bottom surface of a lower outer box before the lower outer box is assembled with a lower guide according to an embodiment. 
         FIG. 10  is an enlarged view of portion A in  FIG. 9 . 
         FIG. 11  is a perspective view showing a lower outer box after the lower outer box is assembled with a lower guide according to an embodiment. 
         FIG. 12  is a perspective view showing a lower surface of a lower outer box after the lower outer box is assembled with a lower guide according to an embodiment. 
         FIG. 13  is a view showing a circuit breaker when viewed from a power source part. 
         FIG. 14  is a view showing a second arc exhaust structure according to an embodiment. 
     
    
    
     DETAILED DESCRIPTION OF THE EMBODIMENTS 
     Hereinafter, the structure and the operation according to the embodiment will be described in detail with reference to accompanying drawings. In the following description based on the accompanying drawings, the same elements will be assigned with the same reference numerals regardless of drawing numbers, and the repetition in the description of the same elements having the same reference numerals will be omitted in order to avoid redundancy. Although the terms “first” and “second” may be used in the description of various elements, the embodiment is not limited thereto. The terms “first” and “second” are used to distinguish one element from the other elements. 
     Reference will now be made in detail to the embodiments of the present disclosure, examples of which are illustrated in the accompanying drawings. 
     In the following detailed description of the preferred embodiments, reference is made to the accompanying drawings that form a part hereof, and in which is shown by way of illustration specific preferred embodiments in which the invention may be practiced. These embodiments are described in sufficient detail to enable those skilled in the art to practice the invention, and it is understood that other embodiments may be utilized and that logical structural, mechanical, electrical, and chemical changes may be made without departing from the spirit or scope of the invention. To avoid detail not necessary to enable those skilled in the art to practice the invention, the description may omit certain information known to those skilled in the art. The following detailed description is, therefore, not to be taken in a limiting sense. 
       FIG. 4  is a perspective view showing a circuit breaker according to the embodiment. 
     Referring to  FIG. 4 , the circuit breaker  100  according to the embodiment includes an upper outer box  200  of defining an upper appearance and a lower outer box  300  of defining a lower appearance. A user may operate a switch lever  500  for controlling a power source of the circuit breaker  100 . 
     For example, if the user operates the switch lever  500  to turn off the power source of the circuit breaker  100 , fixed and movable contactors are separated from each other, so that a high-temperature thermal arc is generated between both contactors. In this case, since an electric conductor and a forming component in the circuit breaker  100  may be damaged by the arc, there is a need to rapidly exhaust the arc in the circuit breaker  100  to an outside. 
     Therefore, when an arc is generated, the arc is exhausted to an outside through a power source arc passage  210  in a power source part of the circuit breaker and the arc is exhausted to an outside through a load part arc passage (refer to reference number  310  in  FIG. 5 ) in a load part of the circuit breaker. 
     Hereinafter, a first arc exhaust structure provided in the load part of the circuit breaker and a second arc exhaust structure provided in a power source part of the circuit breaker will be described in detail. 
     First, the first arc exhaust structure will be described. 
       FIG. 5  is a view of the circuit breaker when viewed at the load part of the circuit breaker.  FIG. 6  is a view showing the first arc exhaust structure according to an embodiment.  FIG. 7  is a perspective view showing the first arc exhaust structure according to an embodiment.  FIG. 8  is a perspective view showing a lower guide according to an embodiment. 
     First, referring to  FIGS. 5 and 6 , the first arc exhaust structure includes an inner box  400 , a load part arc exhaust port  330  connected to the inner box  400 , a load part arc passage  310  for exhausting the arc exhausted from the load part arc exhaust port  330  to an outside of the circuit breaker  100 , and lower and upper guides  320  and  340  for guiding the arc exhausted from the load part arc exhaust porting  330  to the load part arc passage  310 . 
     The lower guide  320  includes a lower inclined surface  321  and the upper guide  340  includes an upper inclined surface  341 . A distance between the upper and lower inclined surfaces  341  and  321  may be gradually narrowed from the load part arc exhaust port  330  to the load part arc passage  310 . 
     For example, the lower inclined surface  321  may be gradually inclined upward from the load part arc exhaust port  330  to the load part arc passage  310 . 
     The upper inclined surface  341  may be gradually inclined downward from the load part arc exhaust port  330  to the load part arc passage  310 . 
     In some cases, an inclined surface may be formed on either the upper guide  340  or the lower guide  320 . 
     The upper inclined surface  341  and the lower inclined surface  321  may be connected to each other through a connecting part (refer to reference number  350  in  FIG. 7 : which may be called a side surface guide) extending in a longitudinal directions. Further, one side of the connecting part (refer to reference number  350  in  FIG. 7 ) is connected to the load part arc passage  310 . 
     Thus, the arc passing through the load part arc exhaust port  330  may be continuously guided by the upper inclined surface  341 , the lower inclined surface  321  and the connecting part (refer to reference number  350  in  FIG. 7 ), so that the arc may flows into the load part arc passage  310 . 
     The arc traveling between the upper and lower inclined surfaces  341  and  321  is exhausted to an outside of the circuit breaker  100  through the load part arc passage  310 . 
     Hereinafter, the lower guide  320  will be described in detail with reference to the accompanying drawings. 
     Referring to  FIGS. 7 and 8 , the lower guide  320  includes an extension surface  322  placed at a lower side of the inner box  400  and formed in a horizontal direction, and the lower inclined surface  321  connected to the extension surface  322  and inclined upward at a predetermined angle. The lower inclined surface  321  may include a plurality of guide protrusions  323 , each of which has, for example, a triangular shape. Further, the lower inclined surface  321  may include a plurality of partition parts  324  for partitioning the passage of the arc exhausted from each load part arc exhaust port  330 . 
     The plurality of protrusions  323  and a plurality of supporting parts  324  may be disposed alternately with each other. The shape and position of the protrusions  323  are not limited to the above. Hereinafter, a path, along which an arc travels in the load part of the circuit breaker, will be described. 
     If an arc is generated while the fixed and movable contactors are being separated from each other, the arc moves into the inner box  400  which constitutes an interior of the circuit breaker  100 . The arc, which passes through the inner box  400 , passes through the load part arc exhaust port  330  which has a narrow passage, and then, travels along the space between the upper and lower inclined surfaces (refer to reference numerals  341  and  321  in  FIG. 6 ) which are connected to the upper and lower sides of the load part arc exhaust port  300 , respectively. Then, the arc travels along the load part arc passage  310 . 
     According to a first arc exhaust structure of the embodiment, since the arc, which passes through the load part arc exhaust port  330 , may move into the load part arc passage  310  by the upper and lower guides (refer to reference numerals  340  and  320  in  FIG. 6 ), it is possible to exhaust the arc to an outside of the circuit breaker  100 . 
     In addition, since the distance between the upper and lower inclined surfaces (refer to reference numerals  341  and  321  in  FIG. 6 ) is gradually narrowed in the moving direction of the arc, the moving speed of the arc is increased so that the arc can be rapidly exhausted to an outside of the circuit breaker  100 . 
       FIG. 9  is a perspective view showing a bottom surface of a lower outer box before the lower outer box is assembled with a lower guide according to an embodiment.  FIG. 10  is an enlarged view of portion A in  FIG. 9 .  FIG. 11  is a perspective view showing a lower outer box after the lower outer box is assembled with a lower guide according to an embodiment.  FIG. 12  is a perspective view showing a lower surface of a lower outer box after the lower outer box is assembled with a lower guide according to an embodiment. 
     Referring to  FIGS. 9 to 12 , the lower outer box  300  includes the upper guide  340  for guiding an arc into the load part arc passage  310 . The upper guide  340  may be formed integrally with the lower outer box  300 . Also, the upper guide  340  may be coupled to the lower outer box  300 . 
     The upper guide  340  includes a guide groove  342  corresponding to a guide protrusion  323  formed in the lower guide  320 . The guide protrusion  323  may be inserted into the guide groove  342 . For example, the guide protrusion  323  may have a triangular shape, and the guide groove  342  may be formed in a triangular shape corresponding to that of the guide protrusion  323 . 
     The lower guide  320  is coupled to the upper guide  340 . In detail, the guide protrusion  332  of the lower guide  320  may be coupled to the guide groove  342  of the upper guide  340 . For another example, by forming a plurality of couplers at mutually correspond positions in sides of the upper and lower guides  340  and  320 , the upper and lower guides  340  and  320  may be coupled to each other. 
     A space is formed by coupling the upper and lower guides  340  and  320  to each other, such that the arc generated from the load part arc exhaust port (refer to reference numeral  330  in  FIG. 7 ) may travel into the load part arc passage (refer to reference numeral  310  in  FIG. 7 ) through the space. 
     In detail, when the guide protrusion  323  of the lower guide  320  is coupled into the guide groove  342  of the upper guide  340 , the space, through which an arc travels, is formed between the upper and lower guides  340  and  320 . 
     The arc generated from the load part arc exhaust port (refer to reference numeral  330  in  FIG. 7 ) may travel into the load part arc passage (refer to reference numeral  310  in  FIG. 7 ) along the arc travelable space formed between the upper and lower guides  340  and  320 , so that the arc may be exhausted to an outside. 
     Although it has been described in the embodiment that the guide groove is formed in the upper guide and the guide protrusion is formed in the lower guide, to the contrary, it is possible that the guide protrusion is formed in the upper guide and the guide groove is formed in the lower guide. 
     Hereinafter, the second arc exhaust structure and a moving flow of an arc will be described. 
       FIG. 13  is a view showing a circuit breaker when viewed from a power source part.  FIG. 14  is a view showing a second arc exhaust structure according to an embodiment. 
     Referring to  FIGS. 13 and 14 , the second arc exhaust structure includes an inner box  400 , a power source arc guide part  240  connected to the inner box  400 , a power source arc exhaust port  250  through which the arc guided by the power source arc guide part  240  is exhausted, and a passage guide part  230  and a passage inclined part  220  which form a power source arc passage. 
     The power source arc guide part  240  may protrude from the inner box  400  by a predetermined length. A cross sectional area of a passage of the power source arc exhaust port  250  may be gradually decreased as the power source arc guide part  240  is closed to the passage guide part  230  in the inner box  400 . Further, the passage guide part  230  may have a round shape. 
     The power source arc guide part  240  may make contact with the passage guide part  230 . For another example, the power source arc exhaust port  250  may make contact with the power source arc guide part  240 . 
     The arc, which passes through the power source arc exhaust port  250 , travels along the passage guide part  230 . The arc, which passes through the passage guide part  230 , travels along the passage inclined part  220  which has a top surface inclined downward at a predetermined angle. Then, after the arc travels along the power source arc passage  210 , the arc is exhausted to an outside of the circuit breaker  100 . 
     Hereinafter, a moving path of an arc in the power source part of the circuit breaker will be described. 
     If an arc is generated while the fixed and movable contactors are being separated from each other, the arc moves in the inner box  400  which constitutes an interior of the circuit breaker  100 . The arc passing through the inner box  400  passes through the power source arc exhaust port  250 , which is a narrow passage, along the power source arc guide part  240 . Then, after a moving direction of the arc is guided by the passage guide part  230  so that the arc travels along the passage inclined part  220 , the arc is exhausted through the power source arc passage  210  to an outside of the circuit breaker  100 . 
     According to the embodiment, since an arc may be guided into the passage guide part through the power source arc guide part  240 , a leakage voltage occurring in the circuit breaker due to the arc can be prevented. 
     Further, since the cross sectional area of the passage is gradually decreased toward the passage guide part  230  so that the moving speed of the arc is increased, the arc can be rapidly exhausted to an outside of the circuit breaker  100 . 
     Further, the top and side surfaces of the passage inclined part  220  are inclined at a predetermined angle, so that the cross sectional area of the passage is gradually decreased as going away from the passage guide part  230 , thereby gradually increasing the moving speed of the arc. Thus, the arc can be rapidly exhausted to an outside of the circuit breaker  100 . 
     In the disclosure, the upper guide, the lower guide and the connecting part may be generally called “load-side arc guide part”. 
     Although embodiments have been described with reference to a number of illustrative embodiments thereof, it should be understood that numerous other modifications and embodiments can be devised by those skilled in the art that will fall within the spirit and scope of the principles of this disclosure. More particularly, various variations and modifications are possible in the component parts and/or arrangements of the subject combination arrangement within the scope of the disclosure, the drawings and the appended claims. In addition to variations and modifications in the component parts and/or arrangements, alternative uses will also be apparent to those skilled in the art.