Abstract:
The present invention relates to a multi-pole switch-fuse arrangement having at least two switch-fuse units into which one fuse link each can be inserted. The switch-fuse arrangement comprises a switching device for closing and breaking the circuits of all switch-fuse units, the switch-fuse arrangement comprising a switching lever, a housing, a drive rod, and a lever mechanism device for actuating a drive rod.

Description:
FIELD OF THE INVENTION 
     The present application relates to a multi-pole switch-fuse arrangement for busbar systems having at least two switch-fuse units for receiving one fuse link each. 
     BACKGROUND OF THE INVENTION 
     Such switch-fuse arrangements are in particular utilized for fusing 3-phase circuits, 3-pole switch-fuse arrangements being employed in particular. 
     Such a switch-fuse arrangement is for example known from EP 1 203 385 B1. 
     Even though switch-fuse arrangements known from the prior art already make possible some safety-promoting elements and a largely convenient and safe operation, there is a demand for further improved switch-fuse arrangements that in particular provide an improvement of the operability and comply with increased safety requirements, while the switch-fuse arrangements are at the same time designed to be simple and reliable in terms of their construction, so that the manufacturing costs for such switch-fuse arrangements can be kept low and the lifetime of a switch-fuse unit can be prolonged and wear and damage can be avoided. 
     BRIEF SUMMARY OF THE INVENTION 
     According to the invention, the switch-fuse arrangement comprises at least two switch-fuse units for receiving one fuse link each, and a contact device, preferably a contact and fastening device, for busbars. The inventive switch-fuse arrangement comprises a switch device having a switching lever that can be toggled between on and an off settings, wherein by means of this switching lever or the switch device the circuits of all switch-fuse units can be closed or broken, so that the user only has to actuate one lever to operate all switch-fuse units at the same time and synchronously. 
     According to the invention, the switch-fuse arrangement comprises a lever mechanism device by means of which the motion of the switching lever that can be toggled between the on and off settings, can be transferred onto a drive rod that can be moved to and fro between a contact setting and a breaker position. The drive rod is spring-loaded relative to the housing, a spring element being provided that biases the drive rod in the direction toward the breaker point. 
     The lever mechanism device of the switch-fuse arrangement according to the invention comprises three transfer levers, a housing transfer lever, a drive-rod transfer lever, and a switching-lever transfer lever. At its one end, the housing transfer lever is fastened to a fixed point on the housing, at its one end the drive-rod transfer lever is connected to the drive rod at a fixed point, and at its one end the switching-lever transfer lever is connected to the transfer lever or to a part of the transfer lever. The respective fastening can take place directly or indirectly, i.e. via a further intermediate element. The direct or indirect connections to the housing, the drive rod and/or the switching lever, are preferably designed to be articulated, in particular the transfer levers are rotatably attached to the relative fastening points. 
     The respectively other ends of the three transfer levers are interconnected in an articulated fashion, preferably at a common point or a common location/position, so that also a relative rotary motion of the three transfer elements relative to each other is made possible. 
     Such a lever mechanism device enables actuation of the drive rod in a particularly simple and advantageous manner, the forces are transferred effectively in a particularly advantageous manner, in particular unwanted strains being avoided leading to a smooth and controlled switching operation. This in particular ensures that the switch operations take place simultaneously with a very high degree of accuracy in all switch-fuse units. 
     In a particularly simple and cost-effective manner it is further ensured that clearly defined positions of the switching lever on the one hand and of the drive rod on the other hand are provided so that both an on setting and also an off setting are reliable set and maintained. It is in particular avoided that switching takes place inadvertently, possibly by accident or in the case of ambiguous switching settings. 
     The simple construction further leads not only to very simple and very reliable and clearly defined operation and switching, but also to a prolonged life of the entire device. 
     In a particularly preferred embodiment of the inventive switch-fuse arrangement, the switching-lever is of two-part design and comprises an operating element and an actuating element that can rotate relative to each other, preferably by at most a predetermined angle α, for example between 30° and 70°, preferably 50° to 70°, particularly preferably 60° to 70°. This has the advantage that when the switching lever is moved from its on setting into the off setting, the operating lever is at first rotated by the user about an angle α without the actuating element being moved or forces being exerted thereon, so that a certain unloaded motion of the operating lever is achieved. This ensures that forces are not already exerted onto the drive rod by accident, for example by inadvertently touching the operating lever, which possibly leads to an unwanted breaking of the circuits of the switch-fuse units. Such an inadvertent, even very short-term, breaking of the circuits or lifting off of the contacts by a motion of the drive rod is to be avoided under all circumstances, since this can possibly also entail arcing even if the contact should be broken only very briefly, which would reduce the life of the switch-fuse unit considerably. 
     It is only after a rotation of the operating element or of the operating lever about a predetermined angle α, for example 60° to 70°, in particular for example 65°, that the operating element likewise entrains the actuating element so that the lever mechanism device exerts a force on the drive rod. 
     In a particularly preferred embodiment, the switching-lever transfer lever is directly connected to part of the actuating element, in particular connected at a fixed point mounted rotatable thereto. 
     In a particularly preferred embodiment, the actuating element comprises a lever element that is fastened rotatably to the housing, in particular about a pivot that also corresponds to the pivot of the switching lever. 
     The end of the lever element opposite the pivot is preferably connected to an end of the switching-lever transfer lever, while the switching-lever transfer lever is connected at its opposite end to the drive-rod transfer lever and the housing transfer lever. 
     The cooperation of the four interconnected levers that are thus present ensures a particularly effective force transfer. 
     In a further preferred embodiment, the housing transfer lever and the drive-rod transfer lever are of essentially identical design, in particular they exhibit the same length. This ensures a particularly even force transfer, it is further also ensured that on manufacturing the switch-fuse arrangements and when installing the corresponding transfer levers, they cannot be mixed up. Mixing up the levers could lead to unwanted malfunctions, which might be possible if the transfer levers were of slightly differing lengths. 
     According to a particularly preferred embodiment, the switch-fuse unit further comprises a locking element that can be moved to and fro relative to a housing of the switch-fuse arrangement between a locking position and a release position, can be moved to and fro in particular linearly. Such a locking element ensures that a switching device or a switching lever of a switching device cannot be actuated by a user, so that the switching device or the switching lever is held or locked in its on setting and/or in its off setting. Possible incorrect operation of the device is thus avoided. This is also an aspect that on its own is inventive and that can be realized independently from the other elements, described above, of the switch-fuse arrangement and leads to advantages that are independent therefrom. 
     In a preferred embodiment, both the locking element and the housing exhibit an opening or a passage that overlap at least partly in the locking position of the locking element so that a lead-sealing element, in particular a lead-sealing wire, can be passed through both openings so that in its locking position the locking element is lead-sealed or secured. As a result, it can be checked and guaranteed that the switch-fuse arrangement has not been actuated without authority or accidently. 
     According to a further, particularly preferred embodiment the switch-fuse arrangement comprises a switching lever having an operating element and an actuating element that can be moved relative to each other, preferably be rotated relative to each other, the actuating element further exhibiting a marker and the operating element comprising a window. The operating element and the actuating element are here designed such that the marker of the actuating element is visible through the window of the operating element only if the switching lever is in its off setting. As a result of a particular advantageous design of the switch-fuse arrangement, in particular in the form as described above, in particular having an inventive lever mechanism device, it is also safeguarded automatically that the switch-fuse units and the switch-fuse arrangement are contactless or de-energized if the marker is visible through the window. In this way, particularly increased safety requirements are fulfilled, in particular faulty operation is avoided. 
     This particular embodiment of a switching lever having an actuating element with a marker and an operating element with a window is on its own inventive also independently of the further design of the switch-fuse arrangement as described above, and it is an independent inventive aspect of a multi-pole switch-fuse arrangement. 
     These and further features and advantages of the invention become apparent using the appended drawings that show particularly advantageous embodiments. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         FIG. 1  shows a cross section through an embodiment of a multi-pole switch-fuse arrangement, the switch-fuse arrangement being in its breaker setting; 
         FIG. 2  shows the embodiment of the circuit fuse arrangement illustrated in  FIG. 1 , the switch-fuse arrangement being in its contact setting or operating setting; 
         FIG. 3  shows the embodiment of the switch-fuse arrangement illustrated in  FIGS. 1 and 2 , the switch-fuse arrangement being in a state in which a user has moved the switching lever from an on setting in the direction of the off setting into an intermediate setting; 
         FIG. 3A  shows a further embodiment of the switch-fuse arrangement, this further embodiment being in a state in which a user has moved the switching lever from an on setting in the direction of the off setting into an intermediate setting; 
         FIG. 4  shows a switching lever and a locking element as they can be used in an embodiment of a switch-fuse arrangement according to the invention; 
         FIG. 5  shows an illustration of a switching lever and of a locking element with parts of a housing of a switch-fuse arrangement according to the present invention, the switching lever being in an off setting; 
         FIG. 6  shows an illustration of a switching lever and of a locking element with parts of a housing of a switch-fuse arrangement according to the present invention, the switching lever being in an on setting; 
         FIG. 7  shows an illustration of a switching lever and of a locking element with parts of a housing of a switch-fuse arrangement according to the present invention, the switching lever being in an intermediate setting; and 
         FIG. 8  shows a top view of part of a housing of a switch-fuse arrangement having a locking element and a cross-sectional view along the line A-A. 
     
    
    
     DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS 
       FIG. 1  shows an embodiment of an inventive switch-lock arrangement  1 , this switch-lock arrangement  1  being a 3-pole switch-fuse arrangement  1  that comprises a total of three switch-fuse units  10  into which one fuse link  20  each can be inserted and, as  FIG. 1  shows, is inserted. 
     The switch-fuse arrangement  1  comprises a housing  80  and is designed such that it can be fastened on a busbar system that in the case of the 3-pole design comprises a total of three busbars, only one busbar  90  being diagrammatically illustrated in  FIG. 1 . The switch-fuse arrangement  1  comprises a switching device having a switching lever  40  that can be toggled between an on setting and an off setting, the switching lever  40  in  FIG. 1  being in its off setting. 
     In the embodiment shown in  FIG. 1 , the switching lever  40  is of two-part design and comprises an operating element  42  (see in detail also  FIG. 4 ) and an actuating element  44 . The actuating element  44  exhibits a marker  46  that in the off setting shown in  FIG. 1  is visible through a window  48  of the operating element so that the status of the switch-fuse arrangement is indicated to the user. This visibility of the marker  48  that is for example implemented by a green field tells the user that the switch-fuse arrangement is in a contactless or de-energized state so that for example fuse links can be replaced. 
     The operating lever  42  and the operating element  44  are rotatably mounted on the housing  80 , in addition a relative rotary motion being possible about a maximum predetermined angle α between the actuating element  42  and the operating element  44 , this in particular in the case of a de-energizing procedure offering particular advantages, see in particular the following description for  FIGS. 3 and 3A . 
     The switching lever  40  is connected to a lever mechanism device  100  that again is connected to a drive rod  60 , so that actuating the switching lever  40  from the on setting into the off setting or vice versa transfers a force and a motion onto the drive rod  60  that is designed to be linearly movable to and fro between a contact setting and a breaker setting, in  FIG. 1  in a horizontal direction from left to right and vice versa. 
     In this embodiment, the operating element  44  of the switching lever  40  comprises a lever arm  45  that is mounted on a pivot  83  so as to be rotatable relative to the housing  80  and whose other end is connected in an articulated manner to the switching-lever transfer lever  160 . By means of this additional lever arm  45 , the force exerted by the user on the switching lever  40  is transferred particularly effectively onto the lever mechanism device  100 . 
     In  FIG. 1 , the switching lever  40  is in its off setting with the result that also the drive rod is in its breaker setting, on the left in  FIG. 1 , the drive rod  60  being biased by means of a spring device  70  into this breaker setting. In the case of the embodiment shown in  FIG. 1 , the spring element  70  is implemented by a helical spring that is arranged between a projection  62  of the drive rod  60  and a projection  82  of the housing  80 . Of course it is possible to provide other spring elements and/or also more than one spring element. 
     After the drive rod  60 , in the setting shown in  FIG. 1 , is in its in breaker setting, the three contacts  64  that are arranged on the drive rod or connected to it and at least partly follow the linear motion of the drive rod, are separate from the associated contacts  84  so that the switch-fuse arrangement is in a de-energized or contactless state. The lever mechanism device  100  comprises a total of three transfer levers, a house transfer lever  120 , a drive-rod transfer lever  140 , and a switching-lever transfer rod  160 , that are connected at their respective one end  122 ,  142 ,  162  in an articulated manner. 
     At a point  124 , the other end of the housing transfer rod  120  is connected to the housing in an articulated manner. The other end of the drive-rod transfer lever  140  is connected at one point  144  to the drive rod  60  in an articulated manner. At a point  164 , the other end of the switching-lever transfer lever  160  is connected to the actuating element  44  of the switching lever  40 . 
       FIG. 2  illustrates the embodiment of the switch-fuse arrangement  1  shown in  FIG. 1 , however the switching lever  40  is in its on setting and the switch-fuse unit is in its contact setting or operating setting. 
     In comparison to the setting shown in  FIG. 1 , the operating lever  42  of the switching lever  40  has been moved by a user toward the left or counter-clockwise into its on setting. This motion also rotated the actuating element  44 , in the view shown in  FIG. 2  counter-clockwise, so that a force was exerted on the lever mechanism device  100 . The switching-lever transfer lever  160  has in this case exerted a force via the common contact point  122 ,  142 ,  162  of the three transfer levers onto the housing transfer lever  120  and the drive-rod transfer lever  140 , so that on account of the fact that the housing transfer lever  120  is firmly connected to the housing  80  at a point  124  the drive rod has been pressed into the contact setting counter to the spring force of the spring device  70 . This leads to the contacts  64  and  84  contacting each other so that the switch-fuse arrangement is in its operating setting or contact setting. 
     In this on setting, the common connection point  122 ,  142 ,  164  of the three transfer levers  120 ,  140 ,  160  has been pushed beyond a dead center position, so that the force exerted by the spring device  70  via the drive rod  60  acts on the housing transfer lever  120  and the drive-rod transfer lever  140  in a direction that presses the switching-lever transfer lever  160  in  FIG. 2  downward so that in this position the spring force of the spring device  70  keeps the switch-fuse arrangement in its contact setting or operating setting. 
       FIG. 3  shows the switch-fuse arrangement illustrated in  FIGS. 1 and 2 , where a user has moved the operating lever  42  from the on setting shown in  FIG. 2  through an angle α in the direction of the off setting. As can be clearly seen in  FIG. 3 , this motion of the operating element  40  about the angle α is not transferred immediately onto the operating element  44 , therefore the operating element  44  and thus the lever mechanism device  100  are still in the position shown in  FIG. 2 . 
     It is not until after the setting shown in  FIG. 3  and on further rotation of the operating element  42  toward the off setting, clockwise in  FIG. 3 , that the actuating element  44 , too, is actuated by the operating element  42 , in this case entrained, so that also the actuating element  44  moves into the off setting, clockwise in  FIG. 3 , as a result of which the lever mechanism device is again brought into the position shown in  FIG. 1  which is supported by the spring force of the spring element  70 , as soon as the dead center point has been overcome. 
       FIG. 3A  shows a further embodiment of an inventive switch-fuse arrangement that is very similar to the switch-fuse arrangement shown in  FIG. 3 , so that reference is made to the description above. Identical or similar elements have been provided with identical reference symbols. 
     In the embodiment shown in  FIG. 3A , the operating lever  42  and the operating element  44  of the switching lever  40  are engineered such that the angle α is larger than in the embodiment shown in  FIG. 3 . As can be seen in  FIG. 3A , moving the operating element  42  will therefore at a later point in time transfer this motion onto the operating element  44 . Even in the position of the operating lever  42  shown in  FIG. 3A , the lever mechanism device  100  is therefore still in the position that corresponds to the position shown in  FIG. 2 , so that the drive rod  60  is still in its contact setting. 
       FIG. 4  shows a perspective view of the operating element  42  and of a locking element  200  as they can be utilized in a switch-fuse arrangement as illustrated in  FIG. 1 to 3 or 3A . 
     The operating element  42  of the switching lever ( 40 , see  FIGS. 1 to 3 ) comprises two side areas or side walls  54  that in each case are provided with a recess  50 , the recess  50  extending over an angular range α. This angular range α defines the maximum relative rotary motion between the operating element  42  and an actuating element ( 44 , see  FIGS. 1 to 3 ). There is further incorporated into a side wall  54  of the operating lever  42  a guide groove into which a projection  202  of the locking element  200  engages. With regard to the functions, reference is made to the following descriptions of  FIGS. 5 to 7 . 
     The angular range α can be matched to the desired device, in particular the operability of the device can be adapted in this way. The angle α can be selected in a wide range, for example between 30° and 70°, however larger angular ranges, in particular between 60° and 70°, being preferred. 
       FIGS. 5 to 7  show part of the housing  80  and part of the operating lever  42  in an exploded view, the locking element  200  being illustrated twice for reasons of clarity, i.e. once in relation to the operating element  42  and once in relation to that part of the housing  80  in which the locking element  200  likewise moves. 
       FIG. 5  shows a state in which the operating element  42  is in its off setting,  FIG. 6  shows a state in which the operating element  42  is in an on setting, and  FIG. 7  shows a state in which the operating element is in an intermediate setting. 
       FIG. 5  shows the operating element  42  in the off setting in which the operating element  42  and the locking element  200  are in such a relative position that the projection  202  of the locking element  200  can move into a first latching recess  56  of the guide groove  52  so that the locking element  200  can be moved into a locking position. If the locking element  200  is situated in the locking position, as shown in  FIG. 5 , the operating element  42  can no longer be rotated and cannot be moved out of its off setting. If the user wants to move the operating element into the on setting, they must first move the locking element  200  out of the first latching recess  56 , i.e. move it in  FIG. 5  toward the right, this motion taking place in corresponding guide grooves  86  of the housing  80  provided for this purpose. 
       FIG. 6  shows the elements illustrated in  FIG. 5 , however the operating lever  42  being in its on setting. The locking element  200  is likewise in its locking position, but now the projection  202  of the locking element  200  engages in a second latching recess  58  of the guide groove  52  of the operating element  42 . In this position, too, of the locking element  200  the operating element  42  cannot be moved so that accidently switching off or moving the operating element  42  into its off setting is avoided. 
       FIG. 7  shows the elements illustrated in  FIGS. 5 and 6 , the operating lever  42  however being in an intermediate setting between the on setting and the off setting. So that the operating element can be in this intermediate setting or can be moved from the on setting into the off setting or vice versa, the locking element  200  must be in its release position, i.e. it must have been moved in  FIG. 7  in the guide grooves  86  of the housing toward the right. In this position, the projection  202  of the locking element  200  rests against the guide groove  52  and cannot engage in one of the latching recesses  56  or  58  so that the locking element cannot be moved into the locking position. 
       FIG. 8  shows a top view of the parts, illustrated in  FIGS. 5 to 7 , of the housing  80  and the locking element  200  and a cross-sectional view along the line A-A. The locking element  200  is in a locking position so that an opening  207  provided in the locking element  200  is aligned with an opening  87  provided in the housing  80 , so that a lead-sealing wire can be fed through both openings. This ensures that the locking element  200  cannot be moved into its release position without destroying the lead-sealing wire. 
     The features disclosed in the description above, the figures, and the claims can be important both individually and in any combination for implementing the invention in the different designs.