Abstract:
A rotary drive for a switch actuated by a toggle lever includes an operative connection which swivels, a first catch element on the operative connection, coupled to the toggle lever, and a second catch element on the operative connection. A mounting plate parallel to the switch base and a rotatable shaft are provided, the rotatable shaft disposed through the mounting plate. The rotary drive further includes a swivel arm on the shaft, a rotary knob coupled to the shaft configured to rotate the shaft. A mechanical connection couples the swivel arm to the second catch element, converting movement of the shaft into a movement of the operative connection. A swivel movement of the toggle lever is transferred to the second catch element, and the swivel arm enables the operative connection to swivel through a rotation of the shaft to move the toggle lever.

Description:
CROSS REFERENCE TO PRIOR RELATED APPLICATIONS 
     This is a U.S. National Phase application under 35 U.S.C. §371 of International Application No. PCT/EP2006/012275, filed on Dec. 20, 2006, and claims the benefit of German Patent Application No. 10 2006 001 404.9, filed on Jan. 11, 2006. The International Application was published in German on Aug. 9, 2007 as WO 2007/087881 A1 under PCT Article 221(2). 
     FIELD 
     The invention relates to the field of electrical switches and in particular, relates to a rotary drive for an electrical switch that can be actuated by a toggle lever. 
     BACKGROUND 
     A rotary drive for a switch with a snap-action mechanism is described, for example, in German patent application DE 2808585 A1. This arrangement is employed to execute the (translatory) toggling movement of a toggle lever that actuates the snap-action mechanism by means of a rotational movement. In order to do this, the toggle lever is gripped by a rotary lever, for which purpose there is a recess in the rotary lever. The rotary lever is swivel-mounted on the actuation side of the housing cover of the electrical switch. 
     German patent specification DE 4300313 C1 describes another proposal for the execution of the toggle movement of a toggle lever on a switch by turning a handle that is rotatably mounted on an actuating shaft. 
     Generally, important switches on operating panels or switching cabinets should be accessible from the outside. A problem arises when such a switch cannot be placed on or in the housing wall and instead, the switch is at a distance behind the wall and should nevertheless be actuatable from the outside. In the case of a switch with rotary-knob, the axis of rotation can be extended, easily passing through the wall. With respect to situations with toggle switches, the switches cannot easily pass through the wall. The only option available is to cut a disproportionately large opening in the wall, provided that a passage through the wall is at all permissible. For such or similar installation situations, it is desirable if an electrical switch with toggle-lever actuation can also be actuated by being turned. 
     SUMMARY 
     It is an aspect of the present invention to provide a device with which a switch with toggle-lever actuation can also be actuated by means of a rotary drive. 
     The present invention provides a rotary drive for an electrical switch attached to a switch base and actuated by a toggle lever having a first end position and a second end position, the toggle lever being disposed at a front of the switch and being swivelable about a first axis of rotation. The rotary drive includes an operative connection having a first portion and a second portion, the operative connection being swivelable about a second axis of rotation, the first axis of rotation and the second axis of rotation approximately coinciding. The rotary drive further includes a first catch element disposed on the first portion of the operative connection, the first catch element being coupled to the toggle lever, and a second catch element disposed on the second portion of the operative connection at a back of the switch. A mounting plate and a rotatable shaft are provided, the mounting plate disposed parallel to the switch base, and the rotatable shaft disposed through the mounting plate. The rotary drive further includes a swivel arm disposed on the shaft, a manual rotary knob coupled to the shaft and configured to rotate the shaft, and a mechanical connection coupling the swivel arm and the second catch element and configured to convert a rotational movement of the shaft into a swiveling movement of the operative connection. A swivel movement of the toggle lever is transferred into a swivel movement of the second catch element, and a length of the swivel arm is configured so as to enable the operative connection to be swiveled to an extent of a rotation of the shaft so as to move the toggle lever from the first end position to the second end position. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
       The present invention will be more readily understood from the detailed description of exemplary embodiments presented below considered in conjunction with the accompanying drawings, in which: 
         FIG. 1  is a perspective view of with clip as the operative connection in accordance with an embodiment of the present invention; 
         FIG. 2  is a perspective view with a frame as the operative connection in accordance with an embodiment of the present invention; and 
         FIG. 3  is an illustration of a lower frame strut mounted so as to swing in accordance with an embodiment of the present invention. 
     
    
    
     DETAILED DESCRIPTION 
     An embodiment according to the present invention is directed to a rotary drive for an electrical switch that is actuated by a toggle lever. The rotary drive includes a rotatably mounted operative connection configured as a frame or clip between the toggle switch and the rotary knob, whose rotation follows the movement of the toggle lever, or which can be actuated by the movement of the operative connection of the toggle lever. A catch arrangement between a shaft situated in a mounting plate and the operative connection serve to actuate the toggle lever and thus the lock of the switch into the appertaining end position. 
     According to an aspect of the present invention, the rotary drive can easily be actuated from the back, if the front of the built-in switch is difficult or impossible to access. Moreover the actuation from the front remains unhindered. 
     The rotary knob generally follows the movement of the toggle lever, so that the various positions of the toggle lever are “mirrored” in various positions of the rotary knob and vice versa. An aspect for the function of a low-voltage switch is that the lock of the switch may have to be reset after it has been tripped. After being tripped, the toggle lever and the rotary knob are in a center position. This position indicates the tripped state to the user. Turning the switch on again by means of the rotary knob is only possible after the lock has been reset. In this context, it is advantageous if the function features (ON, OFF, tripped) are printed or engraved next to the rotary knob so that they are visible to the user. 
     The first catch element located on the front of the switch can be configured as a catch opening. When a clip is used, the end of the upper leg of the clip can also be configured as a fork that surrounds the end of the toggle lever, rather than being configured as a catch opening. 
     The mechanical operative connection can be configured in various advantageous exemplary embodiments. Firstly, the operative connection can consist of a U-shaped clip on whose first leg the first catch element is formed and on whose second leg the second catch element is formed, and the legs, each bent at a right angle, are arranged on a clip bar that moves around the axis of rotation. Secondly, the operative connection can consist of a right-angled frame that surrounds the front, back and two parallel sides of the switch, and the first catch element is formed on the first frame strut located on the front of the switch while the second catch element is formed on the second frame strut located on the back of the switch, and the axis of rotation runs through the frame struts that surround the parallel sides of the switch. 
     The second catch element located on the back of the switch can be configured as an elongated hole. The mechanical connection here consists of a catch pin that is situated on the swivel shaft and that extends through the elongated hole. As an alternative to this, the second catch element can also be configured as a catch pin, whereby the mechanical connection consists of a rod that connects the catch pin and the swivel shaft in an articulated manner, as a result of which a rotational movement of the shaft can be converted into a swiveling movement of the frame. 
     Advantageously, the switch is moved into its two end positions by means of a snap-action mechanism. 
     The mounting plate can be configured as part of a door or flap of a switching cabinet, as a result of which the switch becomes accessible from the back when the flap is opened. Here, an alternative for the mounting of the rotary knob and shaft has to be provided. For instance, the rotary knob can be mounted in the mounting plate configured as a flap in such a manner that it is disengaged from the shaft when the flap is opened. The connection between the rotary knob and the shaft can be configured as a plug-in connection, so that, when the flap is swiveled away, the rotary knob moves along with it, disengaging from the shaft in the process. When the flap is swiveled back in, the rotary knob once again engages with the shaft. 
     Various solutions can be employed to hold the switch in the switching cabinet. One solution is shown in the figures and is described in greater detail there. Another solution can be that the switch holder consists of a stamped and bent component in which the spacers are not configured separately as individual parts. Such embodiments should be easy for a person skilled in the art to implement. An aspect of the present invention provides that the catch elements are properly secured and that the distances are sufficient between the switch holder and the mounting plate, which can also be the back wall of a switching cabinet. 
       FIGS. 1 and 2  depict the following details of the arrangement according to the invention: the back  104  of an electrical switch  100  rests on a switch base  71  and can be affixed thereto in a detachable manner. A toggle lever  120  is visible on the front  102  of the switch  100 . Openings  130  that provide access to the terminals are drawn on the right-hand side of the switch. The switch base includes a plate  71  that lies parallel to the back wall  104  of the switch. The plate (base surface  71 ) is positioned at a distance from the mounting plate  80  by means of supports or spacers  76 . The distance established is such that the catch arrangement having the reference numerals  44 ,  46 ,  48 ,  28  has sufficient space between the base surface  71  and the mounting plate  80 . A flange  72  is formed on both sides of the switch on the switch base  70 . In  FIG. 1 , a clip  20 ′ is attached to the flange  72  so that it can rotate around the axis  30 . In  FIG. 2 , a frame  20  is mounted on the flange  72  so that it can rotate around the axis  30 . 
     The frame in  FIG. 2  is rectangular and has four frame struts  22 ,  23 ,  24  and  25 . The frame struts surround the front  102 , the back  104  and two parallel sides  103 ,  105  of the switch  100 . The axis of rotation  30  of the frame  20  coincides precisely or approximately with the axis of rotation (located inside the switch) of the toggle lever  120 . A rectangular catch opening  26  is formed in the first frame strut  22  located on the front  102  of the switch  100 , and the end of the toggle lever  120  engages into this catch opening  26 . A catch  28  is formed on the second frame strut  24  located on the back  104  of the switch  100 . The mounting plate  80  is parallel to the switch base  71 , and a shaft  42  that can be rotated from the outside by means of a manual rotary knob  40  passes through said mounting plate. This mounting plate can also be a housing wall of a switching cabinet or the like. 
     Arranged on the shaft  42  is a swivel arm  44  that transmits a rotary movement between the swivel arm  44  and the frame catch  28  via the rod  48 . The length of the swivel arm is dimensioned in such a way that the frame can be (completely) swiveled over the extension of the path of rotation of the shaft  42  (or of the manual rotary knob) in such a manner that the toggle lever can be moved from one of its end positions to its other end position. Since the axial position of the frame is approximately flush with the axis of the toggle lever, the toggle lever remains on the first frame strut  22  in the catch opening  26 . The frame strut and the toggle lever execute the same circular arc movement. 
     In  FIG. 1 , the clip  20 ′ includes clip legs  22 ′,  24 ′,  25 ′ and is configured as an operative connection between the toggle switch  120  and the rotary knob  40 . In contrast to the frame  20  according to  FIG. 2 , the clip  20 ′ has only one bearing on the axis  30  on the flange  72 . The clip legs  22 ′ and  24 ′ are shorter than the frame struts  22  and  24 ; they only extend so far as to accommodate the front end of the toggle switch and the catch  28  on the back. The catch opening  26  on the front can be configured as an opening enclosed all around or as a fork. 
       FIG. 3  shows an exemplary embodiment that can be created when the switch  100  is installed horizontally or with a horizontal positioning of the switch holder. Here, the clip leg  24 ′ located on the back  104  of the switch  100 , or else the frame strut  24  located on the back  104  of the switch  100  should remain in the horizontal position when the clip  20 ′ or the frame  20  is swiveled. For this purpose, said lower clip leg  24 ′ or said lower frame strut  24  is rotatably mounted in a shaft  32 . The drawing depicts the situation for the mounting of the frame strut  24  (but not for the mounting of the lower clip leg  24 ′). A person skilled in the art can easily understand and execute the embodiment that is not shown here. The catch arrangement on the bottom frame strut  24  is configured as an elongated hole  28 ′. The pin  46  formed on the swivel arm  44 ′ extends through the elongated hole. When the shaft  42  turns, the swiveling pin  46  moves the bottom frame strut  24  or clip leg  24 ′. By the same token, the frame acted upon from the toggle lever side moves the pin  46 , the swivel arm  44 ′ and the rotary knob  40 . 
       FIG. 3  shows an exemplary embodiment that can be created when the switch  100  is installed horizontally or with a horizontal positioning of the switch holder. Here, the clip leg  24 ′ located on the back  104  of the switch  100 , or else the frame strut  24  located on the back  104  of the switch  100  should remain in the horizontal position when the clip  20 ′ or the frame strut  24  is swiveled. For this purpose, said lower clip leg  24 ′ or said lower frame strut  24  is rotatably mounted in a shaft  32 . The drawing depicts the situation for the mounting of the frame strut  24  (but not for the mounting of the lower clip leg  24 ′). A person skilled in the art can easily understand and execute the embodiment that is not shown here. The catch arrangement on the bottom frame strut  24  is configured as an elongated hole  28 ′. The pin  46  formed on the swivel arm  44 ′ extends through the elongated hole. When the shaft  42  turns, the swiveling pin  46  moves the bottom frame strut  24  or clip leg  24 ′. By the same token, the frame acted upon from the toggle lever side moves the pin  46 , the swivel arm  44 ′ and the rotary knob  40 . 
     The present invention is not limited to the embodiments described herein; reference should be had to the appended claims.