Abstract:
A circuit breaker includes: a housing; a stator accommodated in the housing and connected to a terminal unit; a mover selectively brought into contact with the stator; an opening and closing unit manipulating the mover such that the mover is selectively brought into contact with the stator; and an insulating cover provided in the housing and shielding the mover and the stator from the exterior of the housing, wherein the housing or the insulating cover is made by molding an electrical insulating material.

Description:
CROSS-REFERENCE TO RELATED APPLICATION 
       [0001]    Pursuant to 35 U.S.C. §119(a), this application claims the benefit of earlier filing date and right of priority to Korean Application No. 10-2012-0074703, filed on Jul. 9, 2012, the contents of which is incorporated by reference herein in its entirety. 
       BACKGROUND OF THE INVENTION 
       [0002]    1. Field of the Invention 
         [0003]    The present disclosure relates to a circuit breaker having an insulating cover. 
         [0004]    2. Background of the Invention 
         [0005]    In general, a circuit breaker refers to a device for opening and closing a load device or interrupting a current in the event of an accident such as earthing, short-circuit, or the like, in a transmission &amp; sub-station system or an electrical circuit. Also, a circuit breaker, in which a circuit breaking part is insulated by an insulator and assembled, may generally manually open or close a line in use or may open or close it from a remote area through an electrical manipulator, or the like, outside a metal container. Also, in the event of overload or short-circuit, the circuit breaker automatically cuts off the line to protect an electric power system and a load device. 
         [0006]    A circuit breaker may be classified into an air operation method, a hydraulic operating method, a spring operation method, and the like according to the way in which a circuit breaking part is operated. A circuit breaker may also be classified into an air circuit breaker (ACB) that extinguishes arc by blowing air, a gas circuit breaker (GCB) that extinguishes arc by blowing gas, and the like, according to the way in which arc generated when a mover is separated from a stator by manipulating a circuit breaking part is extinguished. 
         [0007]    In order to cut off an electric circuit as mentioned above, a stator and a mover are installed in a circuit breaking part of a circuit breaker. The stator and the mover are usually in contact to allow a current to flow therethrough, and when a large current flows due to a fault generated in somewhere of the line, the mover is rapidly separated from the stator to interrupt current. 
         [0008]    In the related art circuit breaker, when an overcurrent or a fault current occurs, an operating part rotates a mover to separate it from a stator. The operating part also includes a shaft assembly made of a metal. The shaft assembly is connected to the mover through a link structure. A housing accommodating the mover, or the like, has a hole in which the link structure is inserted and operated. 
         [0009]    When the mover is separated from the stator, a high temperature high pressure arc is generated from a contact between the mover and the stator, and due to the high temperature high pressure arc, a metal component such as the shaft assembly, or the like, may be melted and leaked to the outside through the hole formed in the housing. In this case, phase-to-phase insulation may be weakened by the molten metal residue. 
         [0010]    Meanwhile, when the shaft assembly of the related art breaker is made of plastic, a size of the circuit breaker may be increased. 
       SUMMARY OF THE INVENTION 
       [0011]    Therefore, an aspect of the detailed description is to provide a circuit breaker where it is prevented that a component thereof is molten and leaked out due to high temperature heat resulting from a generation of arc according to separation of a mover and a stator. 
         [0012]    To achieve these and other advantages and in accordance with the purpose of this specification, as embodied and broadly described herein, a circuit breaker includes: a housing; a stator accommodated in the housing and connected to a terminal unit; a mover selectively brought into contact with the stator; an opening and closing unit manipulating the mover such that the mover is selectively brought into contact with the stator; and an insulating cover provided in the housing and shielding the mover and the stator from the exterior of the housing, wherein the housing or the insulating cover is made by molding an electrical insulating material. 
         [0013]    According to an embodiment of the present invention, a phenomenon in which a metal component within the circuit breaker is melted due to an arc generated as a mover and a stator are separated, and the molten metal residue is leaked to the outside to degrade insulating function of the circuit breaker can be prevented. 
         [0014]    Further scope of applicability of the present application will become more apparent from the detailed description given hereinafter. However, it should be understood that the detailed description and specific examples, while indicating preferred embodiments of the invention, are given by way of illustration only, since various changes and modifications within the spirit and scope of the invention will become apparent to those skilled in the art from the detailed description. 
     
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         [0015]    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 exemplary embodiments and together with the description serve to explain the principles of the invention. 
           [0016]    In the drawings: 
           [0017]      FIG. 1  is a view illustrating a circuit breaker according to an embodiment of the present invention. 
           [0018]      FIG. 2  is a partially cut-out view of the circuit breaker according to an embodiment of the present invention. 
           [0019]      FIG. 3  is a view illustrating an insulating cover according to an embodiment of the present invention. 
           [0020]      FIG. 4  is a view illustrating an insulating cover according to another embodiment of the present invention. 
           [0021]      FIG. 5  is a view illustrating a mover assembly according to an embodiment of the present invention. 
           [0022]      FIG. 6  is a view illustrating a coupled state of an insulating cover and a holder according to an embodiment of the present invention. 
           [0023]      FIG. 7  is a view illustrating a coupled state of a bracket and the holder according to an embodiment of the present invention. 
       
    
    
     DETAILED DESCRIPTION OF THE INVENTION 
       [0024]    Hereinafter, a circuit breaker according to an embodiment of the present invention will be described in detail with reference to the accompanying drawings. In the following description, usage of suffixes such as ‘module’, ‘part’ or ‘unit’ used for referring to elements is given merely to facilitate explanation of the present invention, without having any significant meaning by itself. 
         [0025]      FIG. 1  is a view illustrating a circuit breaker according to an embodiment of the present invention, and  FIG. 2  is a partially cut-out view of the circuit breaker according to an embodiment of the present invention. 
         [0026]    Referring to  FIGS. 1 and 2 , a circuit breaker according to an embodiment of the present invention includes a housing  10 , a mover assembly  20 , and an insulating cover  30 . The mover assembly  20  and the insulating cover  30  may be accommodated in the housing  10 . A stator  24  connected to a terminal unit may be provided in the housing  10 . The housing  10  may be fabricated by molding an electrical insulator. 
         [0027]    The mover assembly  20  includes a mover  23  that may be brought into contact with the stator  24 . In a normal state, the mover  23  is maintained in a state of being in contact with the stator  24 , and when an overcurrent or a fault current is generated, the mover  23  rotates about a rotational shaft (by being centered thereon) so as to be separated from the stator  24 . A state in which the mover  23  is in contact with the stator  24  to allow a current therethrough may be an ON state, and a state in which the mover  23  and the stator  24  are separated to prevent a current to flow therethrough may be an OFF state. 
         [0028]    An opening and closing unit for manipulating the mover  23  to an ON position or an OFF position is provided in the housing  10 . For example, the opening and closing unit includes a link  21  and a latch  22 . The link  21  may be connected to a power transmission unit (not shown) by a first shaft  200 . For example, the power transmission unit may be a handle. When an overcurrent or a fault current is generated, the link  21  connected to the other portion of the first shaft  200  may be rotated by manipulating the handle connected to one portion of the first shaft  200 . The power transmission unit is not limited to the example of the handle. The power transmission unit may serve to transmit power to the first shaft  200  upon receiving external power. 
         [0029]    The link  21  and the latch  22  may be connected by the second shaft  201 . The latch  22  may be rotatably connected to the second shaft  201 . Thus, the latch  2  may be manipulated according to a rotation of the link  21 . According to a movement of the latch  22 , the mover  23  may be manipulated to move to an ON or OFF position. 
         [0030]    As the structure in which the mover  23  is turned on or off by the opening and closing unit, a conventional structure may be applied, so a detailed description thereof will be omitted. The first shaft  200 , the second shaft  201 , the link  21 , the latch  22 , and the like, may be made of a metal. 
         [0031]    The insulating cover  30  may be installed in one surface of the housing  10 . In detail, the insulating cover  30  shields the first shaft  200  in which the link  20  is installed and the power transmission unit (not shown), and the like, against a contact point between the mover  23  and the stator  24 . Thus, a molten residue of the first shaft  200 , or the like, due to an arc that may be generated from a contact point between the mover  23  and the stator  24  is prevented from being leaked to an outer side of the housing  10 . 
         [0032]    Hereinafter, a structure of the insulating cover  30  will be described. The insulating cover  30  may be fabricated by molding an electrical insulator. 
         [0033]      FIG. 3  is a view illustrating an insulating cover according to an embodiment of the present invention. 
         [0034]    Referring to  FIG. 3 , the insulating cover  30  according to an embodiment of the present invention includes a link accommodation portion  301 , a shaft insertion hole  302 , and a latch insertion hole  303 . As illustrated in  FIG. 3 , the insulating cover  30  may be coupled to the housing  10  such that one surface thereof is in contact with one surface of the housing  10 . 
         [0035]    The link accommodation portion  301  may be formed in consideration of a size and an operation range of the link  21  such that the link  21  is accommodated and operated therein. The link accommodation portion  301  may be formed as a recess. The link accommodation portion  301  may be formed as a recess having a size sufficient for the link  21  to operate without being interrupted. Since the link accommodation portion  301  is provided as a recess, rather than being open, although a molten residue is generated due to an arc within the insulating cover  30 , leakage of the molten residue to the outside is prevented. 
         [0036]    The latch  22  may be inserted into the latch insertion hole  303  and movable therein. The latch insertion holes  303  may be provided as openings are formed in both sides of the insulating cover  30 . 
         [0037]    Also, the second shaft  201 , to which the latch  22  is connected, may be movably inserted into the shaft insertion hole  302 . The shaft insertion hole  302  may be formed as a portion of an extending surface protruded from a portion of the insulating cover  30  is opened. The shaft insertion holes  302  may be formed in both sides of the insulating cover  30  such that they correspond to the positions of the latch insertion holes  303 . 
         [0038]    The latch insertion hole  303  and the shaft insertion hole  302  may be formed in consideration of operational coverage of the latch  22  and the second shaft  20 , respectively. Namely, the latch insertion hole  303  and the shaft insertion hole  302  may be formed to be open to have a size with which operations of the latch  22  and the second shaft  201  are not interfered. 
         [0039]    Meanwhile, a surface in which the latch insertion hole  303  is formed and a surface in which the shaft insertion hole  302  is formed may be perpendicular to each other. Since the shaft insertion hole  302  and the latch insertion hole  303  are formed not to be positioned on the same plane, a metal residue molten within the insulating cover  30  is prevented from being leaked to the outside through the shaft insertion hole  302  and the latch insertion hole  303 . 
         [0040]    The insulating cover  30  may include a plurality of fastening member insertion holes  304 , and holes (not shown) corresponding to the fastening member insertion holes  304  may be formed in the housing  10 . The insulating cover  30  may be coupled to the housing  10  by fastening members penetrating the fastening member insertion holes  304  and the holes (not shown) formed in the housing  10 . 
         [0041]      FIG. 4  is a view illustrating an insulating cover according to another embodiment of the present invention. 
         [0042]    Referring to  FIG. 4 , the insulating cover  30  according to another embodiment of the present invention includes the link accommodation portion  301  and the shaft insertion hole  302 . The insulating cover  30  may be coupled to the housing  10  such that one surface thereof is in contact with one surface of the housing  10 . 
         [0043]    The link accommodation portion  301  may be formed in consideration of a size and an operation range of the link  21  such that the link  21  is accommodated and operated therein. The link accommodation portion  301  may be formed as a recess. 
         [0044]    The second shaft  201 , to which the latch  22  is connected, may be movably inserted into the shaft insertion hole  302 . The latch insertion hole  303  and the shaft insertion hole  302  may be formed in consideration of operational coverage of the second shaft  20 . Namely, the shaft insertion hole  302  may be formed to be open to have a size with which operations of the latch  22  and the second shaft  201  are not interfered. 
         [0045]    Meanwhile, a latch accommodation portion  305  may be formed in one side of the insulating cover  30  to allow the latch  22  to be positioned and operated therein. The latch accommodation portion  305  may be formed by cutting away a portion of the insulating cover  30  such that it is sufficient for the latch  22  to move therein. 
         [0046]    The surface in which the latch accommodation portion  305  is formed may be at a right angle to the surface in which the shaft insertion hole  302  is formed. Since the shaft insertion hole  302  and the latch accommodation portion  305  are formed such that they are not connected parallelly, a molten metal residue within the insulating cover  30  is prevented from being leaked to the outside through the shaft insertion hole  302  and the latch accommodation portion  305 . 
         [0047]    The insulating cover  30  may include a plurality of fastening member insertion holes  304 , and holes (not shown) corresponding to the fastening member insertion holes  304  may be formed in the housing  10 . The insulating cover  30  may be coupled to the housing  10  by fastening members penetrating the fastening member insertion holes  304  and the holes (not shown) formed in the housing  10 . 
         [0048]    However, the shape of the insulating cover  30  is not limited to the foregoing embodiment. The insulating cover  30  may have any shape as long as it has a structure preventing a molten residue due to an arc, which may be generated as the mover  23  and the stator  24  are separated, from being leaked to the outside. 
         [0049]      FIG. 5  is a view illustrating a mover assembly according to an embodiment of the present invention. 
         [0050]    Referring to  FIG. 5 , a mover assembly according to an embodiment of the present invention includes the mover  23 , a holder  40 , and a bracket  50 . The holder  40  and the bracket  50  are connected to the latch  22 . In detail, a shaft (not shown) penetrating through the holder  40  and the bracket  50  may be connected to the latch  22 . The holder  40  and the bracket  50  may be operated in direction ‘A’ or ‘B’ by the latch  22 . The holder  40  and the bracket  50  may be operated in direction ‘A’ or ‘B’ by the latch  22  together with the mover  23 . With the presence of the holder  40 , the mover  23  can be brought into contact with the stator  24  without wobbling, and contact pressure is provided to the mover  23  to allow the mover  23  to be stably brought into contact with the stator  24 . 
         [0051]      FIG. 6  is a view illustrating a coupled state of an insulating cover and a holder according to an embodiment of the present invention, and  FIG. 7  is a view illustrating a coupled state of a bracket and the holder according to an embodiment of the present invention. 
         [0052]    Referring to  FIGS. 6 and 7 , the bracket  50  may be provided to be in contact with an inner surface of the holder  40 . The bracket  50  may be provided to be in contact with both inner surfaces of the holder  40  opposing thereto. Holes  202  are formed on the bracket  50  and the holder  40  in a connected manner. A shaft (not shown) connected to the latch  22  may be inserted into the hole  202 . 
         [0053]    A hole  41  allowing the mover  23  to be inserted therein may be formed in the holder  40 . One side of the holder  40  may be positioned to be in contact with the insulating cover  30 . When the holder  40  is moved in the direction ‘B’, it may come into contact with the insulating cover  30 . 
         [0054]    The bracket  50  may be formed to extend downwardly from the holder  40 . A hole  51  is formed in the extending portion. A pin (not shown) may be inserted into the hole  51 . The pin (not shown) may connect two brackets  50  positioned to be in contact with both inner surfaces of the holder  40 . 
         [0055]    The side of the holder  40  may extend to the insulating cover  30 , rather than to the bracket  50 . Both sides of the holder  40  may extend to the insulating cover  30 , so when viewed from the inner side of the bracket  50 , the holder  40  may be protruded toward the insulating cover  30  so as to be formed as large as the area ‘S’ relative to the bracket  50 . The holder  40  may be formed such that a portion of the side thereof overlaps with a portion of an outer side of the insulating cover  30 . Since both sides of the holder  40  further extend toward the insulating cover  30 , relative to the bracket  50 , a residue, or the like, due to an arc generation is prevented from being introduced to the interior of the circuit breaker through a space between the bracket  50  and the insulating cover  30 . Since the introduction of the residue, or the like, to the interior of the circuit breaker is prevented, insulating performance of the circuit breaker can be enhanced. 
         [0056]    The foregoing embodiments and advantages are merely exemplary and are not to be considered as limiting the present disclosure. The present teachings can be readily applied to other types of apparatuses. This description is intended to be illustrative, and not to limit the scope of the claims. Many alternatives, modifications, and variations will be apparent to those skilled in the art. The features, structures, methods, and other characteristics of the exemplary embodiments described herein may be combined in various ways to obtain additional and/or alternative exemplary embodiments. 
         [0057]    As the present features may be embodied in several forms without departing from the 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 considered broadly within its scope as defined in the appended claims, and therefore all changes and modifications that fall within the metes and bounds of the claims, or equivalents of such metes and bounds are therefore intended to be embraced by the appended claims.