Abstract:
The present invention relates to a device for cleaning contaminants on a contact portion of an electromagnetic contactor, and more particularly, a device for cleaning contaminants on a contact portion of an electromagnetic contactor in which a magnetic force the acting direction of which is changed in time is generated to the outside of the electromagnetic contactor for cleaning contaminants generated at a contact portion thereof with an arc extinguishing method, thereby effectively and broadly performing the cleaning of contaminants.

Description:
CROSS-REFERENCE TO RELATED APPLICATIONS 
       [0001]    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. 10-2013-0079885, filed on Jul. 8, 2013, 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 invention relates to a device for cleaning contaminants on a contact portion of an electromagnetic contactor, and more particularly, a device for cleaning contaminants on a contact portion of an electromagnetic contactor in which a magnetic force the acting direction of which is changed in time is generated to the outside of the electromagnetic contactor for cleaning contaminants generated at a contact portion thereof with an arc extinguishing method, thereby effectively and broadly performing the cleaning of contaminants. 
         [0004]    2. Description of the Related Art 
         [0005]    In general, electromagnetic contactor is a type of electrical circuit switching device for transferring a mechanical drive and current signal using the principle of an electromagnet, and provided in various industrial facilities, machines, vehicles, and the like.  FIG. 1  is a longitudinal cross-sectional view illustrating an electromagnetic contactor in the related art used in electric vehicles. The configuration of an electromagnetic contactor for electric vehicles may include a case  1 , a housing  2 , a stationary contact point  3  and a movable contact point  4 , and typically further include electrical actuators  5 ,  6 ,  7 ,  8  for driving the movable contact point  4  to control the switching of contact points by an electrical signal. 
         [0006]    Contaminants are adhered to the contact portion (a stationary contact point and a movable contact point) of the electromagnetic contactor. The contaminants may increase a contact resistance of the contact portion and thus a surface thereof can be clearly maintained through a cleaning or conditioning operation. 
         [0007]    A conventional method used for the cleaning operation has been carried out in such a manner that an arc is artificially generated on the contact portion to burn contaminants existing on an electrode surface thereof.  FIG. 2  is a view illustrating an operation diagram according to the cleaning method.  FIG. 2  is a transverse cross-sectional view illustrating a contact portion of an electromagnetic contactor in the related art. A magnetic body for arc extinction  9  is provided in a direction perpendicular to the stationary contact point  3  and movable contact point  4 . An arc is generated in such a form that it is started from any one (indicated by ⊙) of the stationary contact point  3  and enters into the other one (indicated by {circle around (×)}) of the stationary contact point  3  while forming an arc shape. Here, a magnetic force (B) flowing from the top to bottom on the drawing is generated, and an arc is formed with the flow of a current (I) and thus a force according to the Fleming&#39;s left hand rule (F=B×I) is generated between the stationary contact point  3  and movable contact point  4 . Accordingly, the ⊙ indicated electrode receives a force (F) exerted in the “→” direction and {circle around (×)} indicated electrode receives a force (F′) in the “←” direction, thereby cleaning contaminants on a surface of the electrode. 
         [0008]    However, according to a contaminant cleaning method in the related art, the acting direction of a magnetic force (B) is fixed in a predetermined direction so as to generate the magnetic force (B) due to the magnetic body for arc extinction  9  fixed and provided within the electromagnetic contactor and thus forces (F, F′) generated on the arc is also exerted only in a particular direction (horizontal direction (← or →) in  FIG. 2 ), and as a result, the cleaning range of contaminants is restricted, thereby causing a problem in which there is a limit in the cleaning performance. 
       SUMMARY OF THE INVENTION 
       [0009]    The present invention is contrived to solve the foregoing problems, and an aspect of the present invention is to provide a device for cleaning contaminants on a contact portion of an electromagnetic contactor in which a magnetic force the acting direction of which is changed in time is generated to the outside of the electromagnetic contactor for cleaning contaminants generated at a contact portion thereof with an arc extinguishing method, thereby effectively and broadly performing the cleaning of contaminants. 
         [0010]    A device for cleaning contaminants on a contact portion of an electromagnetic contactor according to an embodiment of the present invention may include a housing; a drive unit provided within the housing to generate a driving force; a rotating plate rotatably provided within the housing to be rotated by receiving the driving force; and a magnetic body coupled to both end portions of the rotating plate, respectively, to generate a magnetic force exerted from one side to the other side. 
         [0011]    Here, a drive motor may be provided in the drive unit. 
         [0012]    Furthermore, a driven gear may be coupled to a central shaft of the rotating plate, and the driven gear may be teeth combined with a driving gear of the drive motor to receive a rotational force of the drive motor so as to rotate the rotating plate. 
         [0013]    Furthermore, the device may further include a controller configured to control the rotational speed of the drive motor so as to adjust the rotational speed, rotational direction and rotation angle of the rotating plate. 
         [0014]    On the other hand, a device for cleaning contaminants on a contact portion of an electromagnetic contactor according to an embodiment of the present invention may further include a support provided at a lower portion of the housing to accommodate an electromagnetic contactor therein. 
         [0015]    Furthermore, the support may be height adjustable. 
         [0016]    According to a device for cleaning contaminants on a contact portion of an electromagnetic contactor in accordance with the present invention, a magnetic force the acting direction of which is changed in time may be generated to the outside of the electromagnetic contactor, thereby effectively performing the cleaning of contaminants on the contact portion thereof due to an arc extinction method. 
     
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         [0017]    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 embodiments of the invention and together with the description serve to explain the principles of the invention. 
           [0018]    In the drawings: 
           [0019]      FIG. 1  is a longitudinal cross-sectional view illustrating an inner portion of an electromagnetic contactor according to the related art; 
           [0020]      FIG. 2  is a transverse cross-sectional view illustrating a method of cleaning contaminants on a contact portion of an electromagnetic contactor according to the related art; 
           [0021]      FIG. 3  is a perspective view illustrating a device for cleaning contaminants on a contact portion of an electromagnetic contactor according to the present disclosure; 
           [0022]      FIG. 4  is an exploded perspective view of  FIG. 4 ; and 
           [0023]      FIG. 5  is a transverse cross-sectional view illustrating the operation status of a device for cleaning contaminants on a contact portion of an electromagnetic contactor according to the present disclosure. 
       
    
    
     DETAILED DESCRIPTION OF THE INVENTION 
       [0024]    Hereinafter, a preferred embodiment of the present invention will be described in detail with reference to the accompanying drawings to such an extent that the present invention can be easily implemented by a person having ordinary skill in the art to which the present invention pertains, but it does not mean that the technical concept and scope of the present invention are limited due to this. 
         [0025]    A device for cleaning contaminants on a contact portion of an electromagnetic contactor according to an embodiment of the present invention may include a housing  10 ; a drive unit provided within the housing  10  to generate a driving force; a rotating plate  30  rotatably provided within the housing  10  to be rotated by receiving the driving force; a magnetic body  50  coupled to both end portions  31  of the rotating plate  30 , respectively, to generate a magnetic force exerted from one side to the other side; and a plurality of supports  70  provided at a lower portion of the housing  10  to accommodate an electromagnetic contactor therein. 
         [0026]      FIG. 3  is a perspective view illustrating a device for cleaning contaminants on a contact portion of an electromagnetic contactor according to the present disclosure, and  FIG. 4  is an exploded perspective view of  FIG. 4 . A device for cleaning contaminants on a contact portion of an electromagnetic contactor according to an embodiment of the present invention will be described in detail with reference to the drawings. 
         [0027]    The housing  10  is formed in a substantially cylindrical shape with an opening lower portion. The upper surface of the housing  10  is formed with an area capable of accommodating an electromagnetic contactor, and the height thereof is formed with a predetermined length capable of accommodating a drive unit and a magnetic body  50  which will be described later. The housing  10  may be formed of a synthetic resin material due to molding injection. A supporting shaft  11  may be formed in a protruded manner at a central portion of the housing  10  to rotatably support the central shaft  33  of the rotating plate  30  which will be described later. A coupling groove  12  capable of fixing the central shaft  33  of the rotating plate  30  may be formed along a length direction thereof at the supporting shaft  11 . 
         [0028]    The drive unit is provided within the housing  10 . The drive unit provides a rotational force to the rotating plate  30  which will be described later. A drive motor  20  may be provided in the drive unit. The drive motor  20  may be provided with an AC motor or DC motor to be suitable to a power source, and provided with a motor integrated with a reduction gear to adjust the rotational speed of the driving gear  21 . 
         [0029]    The rotating plate  30  is configured with a body portion  31  and a vane portion  32 . The body portion  31  may be formed with a long rectangular plate shape. The central shaft  33  is vertically formed in a protruded manner at the center of the body portion  31 . The central shaft  33  of the rotating plate  30  is inserted and combined with the coupling groove  12  of the supporting shaft  11  in the housing  10  and thus the rotating plate  30  is rotatably provided in the housing  10 . Here, a bearing (not shown) may be interposed between the central shaft  33  and the coupling groove  12  to smoothly rotate the central shaft  33  of the rotating plate  30  with the support within the supporting shaft  11  of the housing  10 . 
         [0030]    The vane portions  32  of the rotating plate  30  are formed to be bent and extended in a vertically downward direction at both end portions of the body portion  31 . Accordingly, the vane portions  32  vertically formed at both end portions of the body portion  31 , respectively, are formed in the shape of facing each other. The vane portion  32  may be formed of the same material as that of the body portion  31 . 
         [0031]    The driven gear  40  is inserted into the central shaft  33 . The driven gear  40  is fixed and coupled to the central shaft  33  of the rotating plate  30 . The driven gear  40  is teeth combined with the driving gear  21  of the drive motor  20  to receive a rotational force of the drive motor  20  so as to rotate the rotating plate  30 . 
         [0032]    The magnetic body  50  is coupled to an inner lateral surface of the vane portion  32 . An N-pole magnetic body  51  is adhered to one vane portion  32   a,  and a S-pole magnetic body  52  is adhered to the other vane portion  32   b  to generate a magnetic field (B) exerted from the one vane portion  32   a  to the other vane portion  32   b.    
         [0033]    The controller  60  may be provided in part of the housing  10 . The controller  60  may be formed with a PCB board. The controller  60  may control the rotational speed of the drive motor  20  to control the rotational speed, rotational direction, rotation angle and the like of the rotating plate  30 . As a method of controlling the rotational speed of the drive motor  20 , a scheme for adjusting the voltage of the power source received at the drive motor  20  from the power supply unit may be used. The controller  60  may control the rotation angle of the rotating plate  30 , thereby placing the vane portion  32  of the rotating plate  30  at a specific location. Accordingly, it may be possible to adjust the direction of a magnetic field (B) generated from the magnetic body  50 . 
         [0034]    On the other hand, according to another embodiment, the drive motor  20  may be formed with a stepper motor. In this case, the stepper motor may be rotated according to a preset angle even when an additional driven gear  40  or controller  60  is not provided therein, and accordingly, the rotating plate  30  may be sequentially rotated at a predetermined angle. 
         [0035]    A plurality of supports  70  may be formed at a lower portion of the housing  10  to support the housing  10  while being separated from the ground. The support  70  may merely perform the role of a pedestal. According to another embodiment, the support  70  may be formed to be height adjustable. As an example, it is illustrated the support  70  formed in an inscribed slide manner such as antennas or camera tripods. An electromagnetic contactor with various sizes may be accommodated therein by adjusting the height of the support  70 . 
         [0036]    The operation of a device for cleaning contaminants on a contact portion of an electromagnetic contactor according to an embodiment of the present invention will be described with reference to  FIG. 5 . 
         [0037]    An electromagnetic contactor  100  subject to the operation of cleaning contaminants is placed at a lower portion of the housing  10 . The height of the support  70  is adjusted to place a portion having a stationary contact point  103  and a movable contact point  104  at the height of the N-pole and S-pole magnetic bodies  51 ,  52 . 
         [0038]    Power is supplied to the device, and power is also supplied to the electromagnetic contactor  100  to generate an arc. The arc generated from the electromagnetic contactor  100  is generated in such a form that it is started from any one (indicated by ⊙) of the stationary contact point  103  and enters into another one (indicated by {circle around (×)}) of the stationary contact point  103  while forming an arc shape. The arc receives forces (F, F′) according to a magnetic force (B) generated from the N-pole and S-pole magnetic bodies  51 ,  52  to clean contaminants adhered to the contact portion. 
         [0039]    The operation of the controller  60  allows the rotating plate  30  to be rotated by each predetermined angle according to a change of time (for example, sequentially rotated with the location of {circle around (a)}→{circle around (b)}→{circle around (c)}→{circle around (d)}→{circle around (e)}→{circle around (f)} in  FIG. 5 ), and the direction of the magnetic force (B) generated from the N-pole and S-pole magnetic bodies  51 ,  52  is also varied (changed in a clockwise direction based on the direction from the top to bottom in the example of  FIG. 5 ). The direction of forces (F, F′) received by an arc is also varied according to a change of the direction of the magnetic field (B), and thus the forces (F, F′) are exerted on the entire surface of the stationary contact point  103  and movable contact point  104  to effectively clean contaminants. 
         [0040]    A magnetic force (B) generated from the N-pole and S-pole magnetic bodies  51 ,  52  is added to a magnetic force generated from the magnetic body for arc extinction  105  provided within the electromagnetic contactor  100  to determine the resultant direction of the magnetic force (B). Here, when a magnetic force (B) generated from the N-pole and S-pole magnetic bodies  51 ,  52  is formed to be highly greater than that from the magnetic body for arc extinction  105 , the resultant direction of the magnetic force (B) is substantially identical to the direction of a magnetic field (B) generated from the N-pole and S-pole magnetic bodies  51 ,  52 . 
         [0041]    Although the present invention has been described with reference to the foregoing preferred embodiments, it will be easily recognized by those skilled in the art that various modifications and changes can be made without departing from the gist and scope of the invention, and it should be also clearly understood that all these modifications and changes fall in the appended claims.