Abstract:
A remote switching system for electronic switches in a cabinet provides an actuator assembly communicating through a flexible cable with a door handle. The actuator assembly on the electronic switch provides a rotatably captive threaded fastener holding the sheath of the flexible cable to the actuator assembly allow ring a simple single-point tuning of the actuator operation. This tuning may be facilitated by a visual scale showing relative positions between the actuator assembly and an internal slider communicating with the operator of the electronic switch.

Description:
BACKGROUND OF THE INVENTION 
       [0001]    The present invention relates to high-power electrical switches, and in particular to a flexible cable operator for remotely actuating electrical switches such as circuit breakers. 
         [0002]    High-power electrical circuitry is normally placed inside a metal cabinet to protect the electrical circuitry from the external environment and to shield users from potential hazards associated with the operation of the circuitry. 
         [0003]    Often the cabinet provides a handle that serves both to lock a cabinet door and to disconnect electrical power from the interior circuitry before the door is opened. The handle may communicate through a flexible cable operator with a switch inside the cabinet, for example, a circuit breaker, so that when the handle is moved to allow opening of the cabinet door, the circuit breaker is also opened, removing electrical power from the interior circuitry. This feature is normally subject to the mechanical override in the event that the cabinet must be operated with the door open and the circuitry live. 
         [0004]    A flexible cable operator provides a substantially incompressible sheath through which a flexible cable may slide. Opposite ends of the sheath are fixed respectively to a stationary structure of the handle and an actuator frame attached to the circuit breaker housing. One end of the cable is then attached to a movable portion of the handle to communicate this motion through the cable to a slider held within the actuator frame. The slider may provide a collar receiving a toggle operator of the circuit breaker to move the circuit breaker toggle between an “on” and “off” position with movement of the flexible cable by the handle. 
         [0005]    The flexible cable must normally be “tuned” so that the motion at the circuit breaker is sufficient to move the circuit breaker toggle fully between on and off positions when the handle is moved between on and off positions. This tuning is normally accomplished by adjusting a pair of opposed “jam nuts” attached to a threaded barrel on one end of the flexible cable sheath. The jam nuts capture a flange of the actuator frame between them. By loosening one nut and tightening the other, the point of attachment of the sheath to the stationary actuator framework may be shifted to properly center the actuation range of the flexible cable with respect to the operating range of the circuit breaker toggle. 
         [0006]    Adjusting these jam nuts can be relatively difficult requiring partial disassembly of the actuator framework and working within the close confines of that framework to loosen and tighten these two nuts. Once the end of the sheath is properly positioned, the two jam nuts must be tightened together using torque-controlled tools to ensure that the connection does not inadvertently loosen during vibration or use and to ensure that the torque is not so high as to damage the threaded barrel on the end of the sheath causing the sheath to separate from the actuator. 
         [0007]    After moving the jam nuts, it can be difficult to determine whether the adjustment is correct because the handle may not be operated with the jam nuts loose such as would allow the sheath to move freely in this position tested. Accordingly multiple trials may be required for proper adjustment. 
       SUMMARY OF THE INVENTION 
       [0008]    The invention provides an improved actuator allowing single point adjustment of the attachment of the flexible cable sheath to the actuator housing, eliminating the need to loosen, adjust and tighten pairs of jam nuts to precise torques. A visual gauge may be provided to assist in this adjustment process. 
         [0009]    Specifically, the invention provides a switching apparatus for an electrical switch of the type that may be disposed in a cabinet, where the electrical switch has a toggle operator extending from a front of a housing of the electrical switch movable along an actuation axis to switch the electrical switch between an on and off state. The invention includes an actuator frame that can be attached to the housing of the electrical switch proximate to the toggle operator and a slider held by the actuator frame to slide along the actuation axis. The slider provides a collar receiving the toggle operator when the stationary actuator frame is fixed to the housing of the electrical switch, so that movement of the slider along the actuation axis may switch the toggle operator between the on and off states. An actuator cable has an outer sheath and inner flexible cable, and a first end of the outer sheath is attached to one end of the actuator frame so that the inner flexible cable may extend from the first end along the actuation axis, and a first end of the inner flexible cable attached to the slider may move the slider with movement of the inner flexible cable. The attachment between the first end of the outer sheath and the actuator frame provides a threaded ferrule at the first end of the actuator sheath receiving a threaded fastener. A portion of the threaded fastener is received within a pocket on the actuator frame sized to permit rotation of the threaded fastener about the threaded ferrule within the pocket while preventing translation of the threaded fastener along the axis with respect to the actuator frame. 
         [0010]    It is thus a feature of at least one embodiment of the invention to eliminate the need for complex adjustment of jam nuts in tuning a remote actuator for an electronic switch. 
         [0011]    The threaded fastener may provide a substantially circular disk portion having opposed faces abutting corresponding opposed faces of the pocket. 
         [0012]    It is thus a feature of at least one embodiment of the invention to provide an engagement surface that offers low resistance rotation even in the presence of translated forces. 
         [0013]    The threaded fastener may include a nut portion coaxially attached to the circular disk portion and providing wrench-engaging flats. 
         [0014]    It is thus a feature of at least one embodiment of the invention to provide a separate feature better optimized to the different requirements of turning the threaded fastener and retaining the threaded fastener. 
         [0015]    The nut portion is a hex nut with three-quarter inch separated flats (19 mm). 
         [0016]    It is thus a feature of at least one embodiment of the invention to provide a nut fitting standard English and metric wrenches for ready field adjustment. 
         [0017]    The pocket may provide a U-shaped slot conforming to an outer periphery of the substantially circular disk portion of the threaded fastener. 
         [0018]    It is thus a feature of at least one embodiment of the invention to provide an engagement feature in the actuation frame that offers good support to the threaded fastener as may be implemented in a thermoplastic material or the like. 
         [0019]    The switching apparatus may further include an actuator frame cover fitting over the pocket to retain the circular disk portion within the pocket and the nut portion may extend axially beyond the actuator frame and actuator frame cover when fitting over the pocket to be accessible with a wrench. 
         [0020]    It is thus a feature of at least one embodiment of the invention to retain and protect the components of the actuator assembly while allowing ready tuning of the actuator assembly in its assembled form. By combining a nut feature with a captured flange, the nut may be fully exposed for access. 
         [0021]    At least one of the actuator frame and actuator frame cover may provide a viewable scale proximate to a fiducial feature of the slider, the scale indicating a first range of positions of the slider corresponding to switching of the toggle operator in the on state and a second range of positions corresponding to switching of the toggle operator in the off state. 
         [0022]    It is thus a feature of at least one embodiment of the invention to provide immediate visual guidance of the information needed to properly tune the actuator assembly when it is in its fully assembled state. 
         [0023]    The first range of operator positions may be marked in red with at least one of the symbols for I and on and the second range of operator positions is marked in green with at least one of the symbols for O, off, or reset. 
         [0024]    It is thus a feature of at least one embodiment of the invention to provide a visual indicator that also functions to indicate state and proper operation of the actuator assembly. 
         [0025]    The scale may further provide a range of positions between the first and second range of positions indicating the position where the toggle operator is not well defined in either of the on or off state. 
         [0026]    It is thus a feature of at least one embodiment of the invention to guide the operator when tuning the actuator assembly to a tuning that insures proper operation even in the face of manufacturing tolerance stack up. 
         [0027]    The scale may be on the actuator frame cover and the fiducial feature may be a finger extending from the slider through a slot in the actuator frame cover or along either left or right sides of the frame cover adjacent to the viewable scale. 
         [0028]    It is thus a feature of at least one embodiment of the invention to provide an indication of operating status of the actuator assembly that may be readily viewed in most installation configurations and that directly reveals the state of the internal slider. 
         [0029]    The actuator frame cover may engage the actuator frame by an axial slidable engagement of corresponding hooks. 
         [0030]    It is thus a feature of at least one embodiment of the invention to provide a tuning system that accommodates some axial position tolerance implicit in a sliding engagement system. 
         [0031]    At least a portion of the threaded fastener may be exposed through the assembled actuator frame cover and actuator frame at a position to be manipulated by a user viewing the scale. 
         [0032]    It is thus a feature of at least one embodiment of the invention to allow the scale to be used during the tuning operation. 
         [0033]    The actuator frame may be injected molded thermoplastic. 
         [0034]    It is thus a feature of at least one embodiment of the invention to provide a design that accommodates fabrication and an electrically nonconductive polymer. 
         [0035]    The actuator frame may include outer flange portions having holes for receiving machine screws to attach the actuator frame to the electrical switch. 
         [0036]    It is thus a feature of at least one embodiment of the invention to provide a mounting system that accommodates a variety of different electrical switches while positively locating the actuator assembly with respect to the electrical switch simplified assembly in tuning. 
         [0037]    The above aspects of the invention are not intended, to define the scope of the invention for which purpose claims are provided. In the following description, reference is made to the accompanying drawings, which form a part hereof and in which there is shown by way of illustration, and not limitation, a preferred embodiment of the invention. Such embodiment does not define the scope of the invention and reference must be made therefore to the claims for this purpose. 
     
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         [0038]    Reference is hereby made to the following figures in which like reference numerals correspond to like elements throughout, and in which: 
           [0039]      FIG. 1  is a simplified perspective view of an open electrical cabinet showing an exterior accessible handle assembly communicating by a flexible cable with an actuator assembly on an electrical switch; 
           [0040]      FIG. 2  is a side elevational view of the handle assembly showing attachment of the flexible cable to that assembly: 
           [0041]      FIG. 3  is an exploded perspective view of the actuator assembly showing the components of an actuator frame, a slider, and a cover as may together secure an end of the flexible cable; 
           [0042]      FIG. 4  is an exploded view of the assembled actuator assembly positioned with respect to the electronic switch for attachment thereto; 
           [0043]      FIG. 5  is a fragmentary perspective view of an end of the actuator assembly and the slider showing interfacing of a threaded fastener on the flexible cable sheath to the actuator assembly and a lock nut on the flexible cable to the slider; 
           [0044]      FIG. 6  is a cross-sectional view along line  6 - 6  to of  FIG. 4  showing opposed channels in the slider and rails on the actuator frame and actuator cover for guiding the slider; 
           [0045]      FIG. 7  is a perspective view of the assembled actuator assembly showing location of a wrench during the tuning process which may be accomplished with a simple adjustment of the threaded fastener alone; 
           [0046]      FIG. 8  is a top plan view of a label on the cover for identifying the position of the slider within the actuator assembly visible through a slot next to the label; 
           [0047]      FIG. 9  is a fragmentary exploded view of the actuator frame and the actuator cover showing interlocking hooks that allow assembly of the two with a simple sliding motion; 
           [0048]      FIG. 10  is a schematic top plan diagram of the locking tab showing its operation; 
           [0049]      FIG. 11  is a flowchart of the manufacturing steps for assembling the switching system in one embodiment of the present invention; 
           [0050]      FIG. 12  is a schematic representation of the actuator assembly and electronic switch showing alternative locations for a padlock for locking the slider and electronic switch in the off position; 
           [0051]      FIG. 13  is an exploded perspective view of the actuator frame and slider showing multiple positions of locking holes and an optional slot in the slider; and 
           [0052]      FIG. 14  is a cross-sectional view through the collar of the slider taken along line  14 - 14  of  FIG. 3  showing its funnel-like opening. 
       
    
    
     DETAILED DESCRIPTION OF THE INVENTION 
       [0053]    Referring now to  FIG. 1 , an electronics cabinet  10 , for example, constructed of sheet steel, may provide a generally rectangular rear wall  12  to which electrical equipment may be attached including an electrical switch  14  such as a circuit breaker, disconnect switch, or the like. Top and side walls  16  of the electronic cabinet  10  extend forward from the periphery of the rear wall  12  and may be covered by a combination of the front panel  18  and door  20  to define a cabinet interior. The door  20  may hinge between open and closed position, for example, alone, a hinge axis  22  at a front vertical edge of left side wall  16 . 
         [0054]    The front panel  18  may be fixed to one edge of the cabinet  10  against a left side wall  16  and spanning an upper and lower side wall  16  and may support a handle assembly  24 . The handle assembly  24  may include a frame  26  supporting a pivoting handle  28  which may swing between an upper “on” position and a lower “off” position (the latter shown in  FIG. 1 ) as manipulated by a user. 
         [0055]    Referring also to  FIG. 2 , as is generally understood in the art, in the lower “off” position, a latch lever  30  interacting with a latch strike  32  on the door  20  may allow opening of the door  20  from a closed position. Conversely, when the handle  28  is in the upper “on” position, the latch lever  30  may interact with the latch strike  32  to hold the door closed in a locked position. 
         [0056]    Generally, the movable handle  28  controls an actuation linkage  34  attached to a portion of the handle frame  26  inside the cabinet  10 . This actuation linkage  34  in turn may be attached to a flexible cable  36  fitting within a tubular cable sheath  38  together forming a flexible cable assembly  40 . The end of the sheath at the handle assembly  24  may be fixed by a clamp  41  to the handle frame  26  so that movement of the actuation linkage  34  by the handle  28  slides the flexible cable  36  within the sheath  38 . 
         [0057]    As is generally understood in the art, the flexible cable  36  and tubular cable sheath  38  may be relatively freely flexed across their axes of extension but are substantially resistant to changes in dimension in tension or compression along their axes of extension to efficiently transmit the relative motion between the flexible cable  36  and the sheath  38  to a remote location. Generally, motion of the handle  28  through its entire range will provide for a relative movement between the flexible cable  36  and the cable sheath  38  of a predefined distance  42  as will be discussed further below. The actuation linkage  34  controls the relationship between the movement of the handle  28  and the desired predefined distance  42  of the flexible cable  36 . 
         [0058]    Referring again to  FIG. 1 , flexible cable assembly  40  may pass through the interior of the cabinet  10  to an actuator assembly  44  attached to a front face of the electronic switch  14 . 
         [0059]    Referring now to  FIG. 3 , the actuator assembly  44  generally provides an actuator frame  46  presenting a generally upwardly open channel  48  extending along an actuation axis  50 . A slider  52  may fit in an upper length of the channel  48  to slide therealong and may provide a sidewardly extending collar  54  projecting through an opening  56  in the side wall of the channel of the actuator frame  46 . The size of the opening  56  is such as to permit the slider  52  to slide at least by the predefined distance  42  described above. 
         [0060]    The cable assembly  40  may attach to a lower end of the actuator frame  46  (as will be discussed below) so that the flexible cable  36  extending through the sheath  38  may pass into the channel  48  along the actuation axis  50  to attach to the slider  52 . As so assembled, movement of the flexible cable  36  will move the slider  52  along the actuation axis  50  within the actuation frame  46 . 
         [0061]    When the slider  52  is within the channel  48  and the cable assembly  40  attached to the actuator frame  46 , an actuator frame cover  58  may be installed to cover the upper opening of the channel  48  and a portion of the cable assembly  40  within that channel  48 . With the actuator frame cover  58  in place, the collar  54  remains uncovered, projecting from the side of the actuation frame  46 . 
         [0062]    A fiducial feature  59  of the slider  52  may project upward through a slot  60  in the actuator frame cover  58  so that the relative position of the slider  52  within the actuation frame  46  may be visually determined through the actuator frame cover  58 . Generally, the actuator frame cover  38  may be attached to the actuation frame  46  by sliding engagement between a set of downwardly extending hooks  62  on the actuator frame cover  58  and laterally outwardly extending hooks  64  at an upper edge of the channel  48  of the actuator frame  46 , as will be discussed in more detail below. 
         [0063]    Referring also to  FIG. 4 , the actuator frame  46  may be attached to a front face of the electrical switch  14  by means of machine screws  66  passing through holes in horizontally extending flanges  68  in the actuator frame  46  and then through standoffs  70  to threaded bores  72  in the front face of the switch  14 . When the actuator frame  46  is so attached, the collar  54  of the slider  52  surrounds an upwardly extending toggle operator  74  of the electrical switch  14  that may swing or toggle along a toggle operation axis  75 . The toggle operation axis  75  is aligned with the actuation axis  50  of the actuator frame  46  when the actuator frame  46  is attached to the housing of the electrical switch  14 . 
         [0064]    This inter-engagement of the toggle operator  74  is such as to allow movement of the slider  52  and collar  54  to fully actuate electrical switch  14 , moving the toggle operator  74  between an “on” position in which electrical current is conducted through the electrical switch  14  and “off” position in which electrical current is interrupted, when the slider  52  moves by the predefined distance  42 . 
         [0065]    Each of the slider  52 , actuator frame cover  58 , and actuator frame  46  may be constructed of injection molded thermoplastic having a high electrical dielectric to resist electrical conduction through these components to the flexible cable  36  should electrical power be applied to any of these components. 
         [0066]    Referring now to  FIG. 5 , the end of the cable assembly  40  which is attached to the actuator frame  46  may provide a threaded ferrule  76 , for example, crimped to an outer surface of the sheath  38  to present threads on its outer diameter. A threaded fastener  78  comprising, for example, a hex nut  80  having a radially projecting circular flange  82  attached at one face of the hex nut  80  may be received on the threaded ferrule  76 . The hex nut  80  may, in one example, provide for opposed flats receivable by a standard open end wrench and separated by three-quarters of an inch or approximately 19 mm to be readily adjusted with common wrench sizes. 
         [0067]    The radially projecting circular flange  82  may be substantially cylindrical like a washer and of greater diameter than the diameter of a circle circumscribing the flats of the hex nut  80 . For example, the circular flange  82  may have a diameter of 1 inch and an axial thickness of approximately 9/16 of an inch. The lower end of the actuator frame  46  may provide a U-shaped groove  84  of equal diameter to the circular flange  82  that may receive the circular flange  82  while allowing the hex nut  80  to extend outward from the actuator frame  46  to be readily accessible. The U-shaped groove  84  is sized to permit free rotation of the circular flange  82  therein but to substantially resist translation of the circular flange along the actuation axis  50 . 
         [0068]    It will be appreciated that rotation of the threaded fastener  78  will move the threaded fastener along the threaded ferrule  76  adjusting the relative point of attachment of the sheath  38  to the actuator frame  46  as will be discussed further below. When the actuator frame cover  58  of  FIG. 3  is on the actuator frame  46 , the circular flange  82  is captured between the groove  84  and underside of the actuator frame cover  58  blocking movement of the circular flange  82  against substantial upward movement and removal. 
         [0069]    Referring still to  FIG. 5 , the end of the flexible cable  36  extending from the sheath  38  within the channel  48  may be threaded with threads  86  to receive a lock nut  88  designed to stay substantially fixed on the threads  86  once the lock nut  88  and threads  86  are engaged. A wide variety of lock nuts of this type are known including those with jamming threads or deforming features that engage the threads  86 . The lock nut  88  may be received within a channel  90  of the slider  52  opening upward and having laterally extending slots  92  that capture the axially opposed faces of the lock nut  88  against movement along actuation axis  50  with respect to the slider  52 . Thus, movement of the flexible cable  36  within the sheath  38  will move the slider  52 . 
         [0070]    Referring now also to  FIG. 6 , the slider  52  may have a lower axial channel  94  and upper axial channel  96  on opposed lowering upper faces of the slider  52  extending generally parallel to the actuation axis  50 . The lower axial channel  94  and upper axial channel  96  may each engage a corresponding axial guide rail  97  with axial guide rail  97  extending upward from a bottom of the channel  48  of the actuator frame  46  and guide rail  98  extending downward from the underside of the actuator frame cover  58 . These two rails  97  and  98  provide a low friction interface of plastic on plastic allowing smooth sliding action of the slider  52  within the channel  48  of the actuator frame  46  and resist any rocking or torquing action that might jam or cam the two surfaces. 
         [0071]    Referring now to  FIGS. 7 and 8 , adjustment of the threaded fastener  78  may be conducted by placing a standard open end wrench  100  on the hex nut  80  which protrudes from out of the assembled actuator frame  46  and actuator frame cover  58 . This process is normally conducted by the manufacturer but can also be performed by the end-user. In order to make this adjustment, the handle  28  (shown in  FIG. 1 , but typically a jig when this is done in a manufacturing environment) may be moved to the “off” position and an off extreme point  102  may be established with respect to a visual scale  104  printed on an upper surface of the actuator frame cover  58  along slot  60  through which the fiducial feature  59  may be viewed. The off extreme point  102  may be a center point of the fiducial feature  59  when the handle  28  is in the “off” position. 
         [0072]    The handle  28  may then be moved to the “on” position and the on extreme point  106  established with respect to the scale  103 . The predefined distance  42  will be the distance between the on extreme point  106  and the off extreme point  102 . The threaded fastener  78  may then be adjusted to move a center point  108  between the off extreme point  102  and on extreme point  106  to be approximately centered at a center point  110  of the visual scale  104 . The tuned assembly is then sent to the user who normally need not adjust the threaded fastener  78  on-site. 
         [0073]    The visual scale  104  includes a dead zone  112  about the center point  110  indicating the region where the position of the toggle operator  74  shown in  FIG. 4  cannot reliably be known to be in either the “on” or “off” position because of normal manufacturing tolerances in the operation of the electrical switch  14 , play between the collar  54  and the toggle operator  74 , play between the axial location of the actuator frame cover  58  and the actuator frame  46  and other tolerance factors. Above the dead zone  112  will be an on zone  114  indicating a position of the fiducial feature  59  when the electrical switch  14  is reliably in the on state. This on zone  114  may be marked with a color red, indicating the hazard of active electrical components within the cabinet  10 , and the symbols for the on state including the international symbol of an I and the word “on”. Below the dead zone  112  will be an off zone  116  which may be labeled in a green color and include the international symbol for off of O, the word “off” and the word “reset”. 
         [0074]    Referring now to  FIGS. 9 and 10 , the configuration of the components described above greatly simplifies assembly of the actuator assembly  44 , flexible cable assembly  40 , and handle assembly  24  as well as assembly within a system as shown in  FIG. 1  including electrical switch  14  and cabinet  10 . 
         [0075]    In that assembly process conducted at the manufacturer, the actuator frame  46  is first attached to the switch  14  as discussed above with respect to  FIG. 4  and as indicated by process block  120 . At this time, both the actuator frame cover  58  and the cable assembly  40  may be removed making this attachment process relatively simple by eliminating the weight and/or torque imparted by these additional components. 
         [0076]    As indicated by process block  122 , the threaded fastener  78  may then be assembled onto the threaded ferrule  76  as shown in  FIG. 5  and the lock nut  88  may be attached to the threads  86  on the flexible cable  36  as shown in  FIG. 5 . 
         [0077]    At process block  124 , the slider  52  may be inserted into the channel  48  so that the collar  54  fits around the toggle operator  74  as shown in  FIG. 4 . Per process block  126 , the threaded fastener  78  may then be inserted into the groove  84  of the actuator frame  46  and, as indicated by process block  128 , the actuator frame cover  58  installed on the actuator frame  46  and the nut  88  inserted into the slots  92  of the slider  52 . it will be understood that in some cases these steps may be duplicated by the end-user in the event of repair or tuning. 
         [0078]    Referring now to  FIGS. 6 and 9 , the installation of the actuator frame cover  58  on the actuator frame  46  may be accomplished by simply placing the actuator frame cover  58  down against the upper edge of the actuator assembly  44  so that the hooks  62  may pass past the hook  64  discussed above with respect to  FIG. 3 . The actuator frame cover  58  may then be moved axially to engage hooks  62  and  64  which serve to prevent lifting off of the actuator frame cover  58 . 
         [0079]    The actuator frame cover  58  may include a downwardly extending lock tab  130  that passes over a locking ramp  132  on an inner vertical wall of the actuator frame  46  near groove  84 . As shown in  FIG. 10 , axial sliding of the actuator frame cover  58  moves the lock tab  130  over the interior ramp  132  causing it to deflect inward and then spring outward against the perpendicular face  134  of the ramp  132  preventing retraction of the actuator frame Cover  58  under normal use. Retraction of the actuator frame cover  58  can be provided by the insertion of a screwdriver blade  135  through an aperture  138  in the bottom of the channel  48  of the actuator frame  46  to pry the lock tab  130  over ramp  132  allowing the actuator frame cover  58  to be released. 
         [0080]    Referring again to  FIG. 10 , in a final step  129 , the handle  28  may be positioned successively in its “on” and “off” positions and the threaded fastener  78  adjusted as described above with respect to  FIG. 8 . 
         [0081]    Referring now to  FIGS. 1 ,  11 , and  12 , in one embodiment, a lock aperture  138  may be provided in one vertical wall of the actuator frame  46  providing a transverse path  135  perpendicular to actuation axis  50  through aperture  138  and opening  56  in the actuator frame  46 . This transverse path  135  allows for the insertion of the shank  136  of a padlock  137  through the actuator assembly  44 . In a first position  139   a,  the shank  136  may pass through a transverse slot  140  in the slider  52 , when the slider  52  is in the off position, to lock the slider  52  against motion that would allow movement of the collar  54  or the toggle operator  74  (shown in  FIG. 4 ). 
         [0082]    Alternatively, in a second position  139   b,  the aperture  138  may be moved to position  134 ′ so that the shank  136  of the padlock  137  may pass adjacent to an upper wall of the slider  52  to prevent movement of the slider  52  toward the “on” position, yet without requiring slot  140 . 
         [0083]    As shown in  FIG. 11 , a body  142  of the padlock  137  may be positioned on either side of the frame  46  for flexible access to a key slot or combination operator of the padlock  137 . The use of a padlock  137  directly on the actuator assembly  44  provides additional security against inadvertent activation of the switch  14 , the latter as may he accessible through the cabinet door  20  when the handle  28  is in the “off” position. 
         [0084]    Referring to  FIG. 13 , the collar  54  may provide an opening  144  through which the toggle operator  74  extends that narrows downward toward the electrical switch  14 , like a funnel, to the substantially equal opening with two times the width of the toggle operator  74  at its entrance into the collar  54 . In this way, the collar  54  not only serves to move the toggle operator  74  but, when locked, prevents movement of the toggle operator  74  while still accommodating the pivoting action of the toggle operator  74 . 
         [0085]    A lower portion of the collar  54  may be expanded in a flange  146  to provide a stabilizing surface that rests against the upper surface of the switch  14  for improved stability. Generally, in the locked position, the machine screws  66  (shown in  FIG. 4 ) will still be accessible allowing removal of the actuator assembly  44  in the event of an inability to remove the padlock at a time when recommissioning of the switches is desired. 
         [0086]    Certain terminology is used herein for purposes of reference only and thus is not intended to be limiting. For example, terms such as “upper”, “lower”, “above”, and “below” refer to directions in the drawings to which reference is made. Terms such as “front”, “back”, “rear”, “bottom” and “side”, describe the orientation of portions of the component within a consistent but arbitrary frame of reference which is made clear by reference to the text and the associated drawings describing the component under discussion. Such terminology may include the words specifically mentioned above, derivatives thereof, and words of similar import. Similarly, the terms “first”, “second” and other such numerical terms referring to structures do not imply a sequence or order unless clearly indicated by the context. 
         [0087]    When introducing elements or features of the present disclosure and the exemplary embodiments, the articles “a”, “an”, “the” and “said” are intended to mean that there are one or more of such elements or features. The terms “comprising”, “including” and “having” are intended to be inclusive and mean that there may be additional elements or features other than those specifically noted. It is further to be understood that the method steps, processes, and operations described herein are not to be construed as necessarily requiring their performance in the particular order discussed or illustrated, unless specifically identified as an order of performance. It is also to be understood that additional or alternative steps may be employed. 
         [0088]    It is specifically intended that the present invention not be limited to the embodiments and illustrations contained herein and the claims should be understood to include modified forms of those embodiments including portions of the embodiments and combinations of elements of different embodiments as come within the scope of the following claims. All of the publications described herein, including patents and non-patent publications, are hereby incorporated herein by reference in their entireties.