Abstract:
Disclosed is an electrical circuit making and breaking switch including a housing and a first electrical contact located in the housing. A block mechanism is located in the housing and includes a second electrical contact and a stopper disposed in mechanical communication with the second electrical contact. The stopper is positionable in the block mechanism, wherein a change in the position in the stopper results in a change in a contact position of the second electrical contact relative to the block mechanism. Further disclosed is a lateral block mechanism for an electrical circuit making and breaking switch. The lateral block mechanism includes two carrier assemblies and a connecting piece located between the two carrier assembles and secured thereto. An electrical contact is located at at least one of the two carrier assemblies.

Description:
BACKGROUND OF THE INVENTION 
       [0001]    The subject invention relates generally to circuit makers and breakers. More particularly, the subject invention relates to auxiliary switches for contactors. 
         [0002]    Contactors are often provided with an auxiliary switch which typically includes a plurality of sets of electrical contacts for controlling auxiliary circuits such as operating coils of auxiliary devices. Auxiliary switches typically are configured depending on the auxiliary device with which the auxiliary switch is to be used as, for example, normally open-normally closed (NO-NC), normally closed-normally open (NC-NO), two normally open (2NO), or two normally closed (2NC). If a user changes from a device requiring, for example, an NC-NO auxiliary switch to, for example a device requiring a 2NO auxiliary switch, the user must purchase the desired 2NO auxiliary switch and replace the NC-NO auxiliary switch with it. This requires the user to incur cost to purchase additional auxiliary switches for the desired configurations. A cost-effective solution allowing the user to utilize a single auxiliary switch assembly for multiple device configurations would be well received in the art. 
       BRIEF DESCRIPTION OF THE INVENTION 
       [0003]    According to one aspect of the invention, an electrical circuit making and breaking switch includes a housing and a first electrical contact located in the housing. A block mechanism is located in the housing and includes a second electrical contact and a stopper disposed in mechanical communication with the second electrical contact. The stopper is positionable in the block mechanism, wherein a change in the position in the stopper results in a change in a contact position of the second electrical contact relative to the block mechanism. 
         [0004]    According to another aspect of the invention, a lateral block mechanism for an electrical circuit making and breaking switch includes two carrier assemblies and a connecting piece located between the two carrier assembles and secured thereto. An electrical contact is located at at least one of the two carrier assemblies. 
         [0005]    These and other advantages and features will become more apparent from the following description taken in conjunction with the drawings. 
     
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         [0006]    The subject matter, which is regarded as the invention, is particularly pointed out and distinctly claimed in the claims at the conclusion of the specification. The foregoing and other features and advantages of the invention are apparent from the following detailed description taken in conjunction with the accompanying drawings in which: 
           [0007]      FIG. 1  is a perspective view of an embodiment of an auxiliary switch; 
           [0008]      FIG. 2  is a perspective view of a partially disassembled switch of  FIG. 1 ; 
           [0009]      FIG. 3  illustrates an embodiment of a cover assembly for the auxiliary switch of  FIG. 1 ; 
           [0010]      FIG. 4  illustrates an embodiment of a cover for the auxiliary switch of  FIG. 1 ; 
           [0011]      FIG. 5  illustrates a lateral block mechanism disposed in a cover for the auxiliary switch of  FIG. 1 ; 
           [0012]      FIG. 6  is a perspective view of a partially disassembled switch of  FIG. 1 ; 
           [0013]      FIG. 7  is a perspective view of an embodiment of a fixed contact for the auxiliary switch  FIG. 6 ; 
           [0014]      FIG. 8  illustrates an embodiment of a lateral block mechanism of an auxiliary switch; 
           [0015]      FIG. 9  illustrates an embodiment of a carrier for the lateral block mechanism of  FIG. 8 ; 
           [0016]      FIG. 10  illustrates an embodiment of a moving contact for the auxiliary switch of  FIG. 8 ; 
           [0017]      FIG. 11  illustrates another embodiment of a lateral block mechanism of an auxiliary switch; and 
           [0018]      FIG. 12  illustrates yet another embodiment of a lateral block mechanism of an auxiliary switch. 
       
    
    
       [0019]    The detailed description explains embodiments of the invention, together with advantages and features, by way of example with reference to the drawings. 
       DETAILED DESCRIPTION OF THE INVENTION 
       [0020]    Shown in  FIG. 1  is an embodiment of an auxiliary switch  10 . The mechanism of the switch  10  is disposed in a housing  12  with an activator  14  extending through an activator opening  16  in the housing  12 . In some embodiments, as illustrated in  FIG. 1 , the housing  12  includes a base  20  and a cover  18 . The base  20  and the cover  18  may be assembled by, for example, a snap fit, or by a plurality of plastic rivets  22  (best shown in  FIG. 2 ) extending from, for example, the cover  18  through a plurality of rivet holes  24  in the base  20 . It is to be appreciated that other assembly configurations, for example, threaded fasteners (not shown) may be utilized to secure the cover  18  to the base  20 . 
         [0021]    In some embodiments, as shown in  FIG. 3 , the cover  18  comprises an outer cover  26  and an inner cover  28 . As best shown in  FIG. 4 , outer cover  26  includes a cover opening  30  and one or more snap features  32 . Referring again to  FIG. 3 , the inner cover  28  is positioned over the cover opening  30 , and may be held in position relative to the outer cover  26  via the one or more snap features  32 . It is to be appreciated that the inner cover  28  may be secured to the outer cover  26  via other means, for example, one or more threaded fasteners (not shown), an adhesive, or an interference fit. 
         [0022]    In some embodiments, as shown in  FIG. 5 , the inner cover  28  includes on or more guides  34  to position a lateral block mechanism  36  at the inner cover  28 . The lateral block  36  may be assembled to the inner cover  28  via the one or more guides  34 , and the inner cover  28  assembled to the outer cover  26  via the one or more snap features  32  to form a cover assembly  18 . 
         [0023]    Referring now to  FIG. 6 , shown is a view of an embodiment of the switch  10  with the cover  18  removed. At least two electrically conductive fixed contacts  38  are disposed in the base  20 . As shown in  FIG. 7 , in some embodiments each fixed contact  38  includes two contact tips  40 , one contact tip  40  disposed on each contact face  42  of the fixed contact  38 . Disposing two contact tips  40  at each fixed contact  38  aids in simple conversion of the switch  10  from NO to NC configuration and from NC to NO configuration. The lateral block mechanism  36  is slidably disposed, and includes two electrically conductive moving contacts  44 . The lateral block mechanism  36  is connected to the activator  14  such that when the activator  14  translates in the activator opening  16 , the moving contacts  44  slide in the inner cover  28  from a first position to a second position. The particular type of auxiliary switch  10  illustrated in  FIG. 6  is a normally closed-normally closed (2-NC) meaning that the moving contacts  44  are normally engaged with the fixed contacts 38  closing a circuit in the auxiliary switch  10  as shown in  FIG. 6 , and when the circuit needs to be opened, or when a fault is encountered, the moving contacts  44  move away from the fixed contacts  38  thus opening the circuit. 
         [0024]    An embodiment of the lateral block mechanism  36  is shown in more detail in  FIG. 8 . The lateral block mechanism  36  comprises two carriers,  46   a  and  46   b , and a connecting piece  48  disposed therebetween. Each carrier  46  has carrier legs  50  extending from each end of a carrier body  52 . In the embodiment of  FIG. 8 , the carrier body  52  is substantially cylindrical and two carrier legs  50  extend from each end thereof. It is to be appreciated, however, that other shapes of carrier bodies  52  and other quantities of carrier legs  50 , for example, three or four carrier legs  50 , are contemplated within the present scope. As shown, each carrier leg  50  includes a carrier barb  54  which extends outwardly from the carrier leg  50  relative to a carrier axis  56 . The carriers  46   a  and  46   b  are assembled into a single lateral block mechanism  36  by inserting the carrier barbs  54  at one and of each carrier  46  into corresponding carrier slots  58  in the connecting piece  48 . In some embodiments, the carrier legs  50  of the two carriers  46  are inserted into the annular connecting piece  48  from opposite ends of the connecting piece  48 , and when assembled, the carrier barbs  54  extend outwardly through the carrier slots  58  in the connecting piece  48 . 
         [0025]    Each carrier  46  includes a pressure plate  60  fixed at first end  62  of the carrier body  52 . One moving contact  44  is installed onto the carrier body  52 , with a compression spring  64  located between the pressure plate  60  and the moving contact  44  on the carrier body  52 . A position of the moving contact  44  on the carrier body  52  is determined by a location of a stopper  66  inserted through the carrier body  52 . As best shown in  FIG. 9 , each carrier body  52  includes a plurality of stopper holes  68 , for example two stopper holes  68 , extending therethrough. The stopper  66  is inserted into the desired stopper hole, either  68   a  or  68   b , such that the moving contact  44  is disposed between the compression spring  64  and the stopper  66 . With the stopper  66  installed, the compression spring  64  exerts a force on the moving contact  44  thus securing the moving contact  44  between the compression spring  64  and the stopper  66 . To change a position of the moving contact  44  on the carrier body  52 , the stopper  66  is installed into one of the other stopper holes  68  of the plurality of stopper holes  68 . Correspondingly, the force exerted by the compression spring  64  on the moving contact  44  will vary by changing the position of stopper  66 . 
         [0026]    In some embodiments, as shown in  FIG. 9 , the carrier body  52  includes one or more body guides  70 , which in the embodiment of  FIG. 9  are two channels disposed approximately 180 degrees from each other. The moving contact  44 , as shown in  FIG. 10 , includes corresponding projections  72  which fit into the body guides  70  and guide the moving contact  44  between positions. It will be appreciated that other guide configurations may be utilized. For example, the projections  72  may be disposed on the carrier body  52  and the guides  70  may be disposed on the moving contact  44 . 
         [0027]    The lateral block mechanism  36  of  FIG. 8  is configured for a 2-NC auxiliary switch  10 . In this configuration, a first carrier  46   a  is installed into the connecting piece  48  such that the pressure plate  60  is nearer the connecting piece  48  than the moving contact  44 . Further, in this embodiment, the stopper  66  is installed in the first carrier  46   a  in the stopper hole  68   a  nearest to the pressure plate  60 . The second carrier  46   b , on the other hand, is installed into the connecting piece  48  such that the moving contact  44  is nearer the connecting piece  48  than the pressure plate  60 . In the second carrier  46   b , the stopper  66  is installed in the stopper hole  68   a  nearest the pressure plate  60 . Referring again to  FIG. 6 , ends  74  of each pressure plate  60  are fixed in a plurality of locating blocks  76  in the base  20  thus fixing a position of the pressure plates  60  in the base  20 , and the moving contacts  44  in position contacting the fixed contacts  38 . 
         [0028]    The lateral block mechanism  36  can easily be restructured to accommodate other auxiliary switch  10  configurations, for example normally open-normally open (2NO), normally open-normally closed (NO-NC) and/or normally closed-normally open (NC-NO). To convert an auxiliary switch  10  from the 2NC configuration of  FIG. 8  to a 2NO configuration, both carriers,  46   a  and  46   b  are inverted in the connecting piece  48 . This is accomplished by inserting carrier  46   a  into the connecting piece  48  such that the moving contact  44  is nearer to the connecting piece  48  than the pressure plate  60  is, and by inserting carrier  46   b  in the connecting piece  48  such that the pressure plate  60  is nearer the connecting piece  48  than is the moving contact  44 . Further, the stopper  66  is installed in each carrier  46  in the stopper holes  68  furthest from the pressure plate  60 . 
         [0029]    Further, as shown in  FIG. 11 , in some embodiments, the second carrier  46   b  can be inverted in the lateral block mechanism  36  by inserting the second carrier  46   b  into the connecting piece  48  such that the pressure plate  60  is nearer the connecting piece  48  than the moving contact  44 . This will configure the auxiliary switch  10  to an NC and NO configuration. As shown in  FIG. 12 , the auxiliary switch  10  can be converted to an NO-NC configuration, by inverting only carrier  46   a  and leaving the position of carrier  46   b  unchanged. Stoppers  66  may be placed either in stopper hole  68  depending on position of the fixed contacts  38 . 
         [0030]    The changeability of the structure of the lateral block mechanism  36  by moving the stopper  66  between stopper holes  68   a  and  68   b  and/or by inverting one or both of the carriers  46   a  and  46   b  allows a user to simply reconfigure the auxiliary switch  10  to accommodate several different needs as described above. Further, the lateral block mechanism  36  is secured to the outer cover  28  which in turn is assembled to outer cover  26  via a snap fit. Thus reconfiguration of the auxiliary switch  10  is simple, and there is no need to replace the auxiliary switch  10  with a different one. 
         [0031]    While the invention has been described in detail in connection with only a limited number of embodiments, it should be readily understood that the invention is not limited to such disclosed embodiments. Rather, the invention can be modified to incorporate any number of variations, alterations, substitutions or equivalent arrangements not heretofore described, but which are commensurate with the spirit and scope of the invention. Additionally, while various embodiments of the invention have been described, it is to be understood that aspects of the invention may include only some of the described embodiments. Accordingly, the invention is not to be seen as limited by the foregoing description, but is only limited by the scope of the appended claims.