Abstract:
A hand-guided apparatus may include an operating lever, a switch, and an intermediate lever. The operating lever may actuate a function of the hand-guided apparatus, be constructed in an elongated manner and be pivotably attached to a housing of the apparatus. The switch actuates the function and is arranged in the housing. The intermediate lever mechanically actuates the switch. The operating lever includes a safety element enabled to be pretensioned and shifted along a longitudinal axis of the operating lever. The operating lever and the intermediate lever are enabled to be mechanically coupled by shifting the safety element into a pretensioned state to enable actuation of the switch by pivoting of the operating lever. The operating lever and the intermediate lever are enabled to be mechanically decoupled by shifting the safety element into a relaxed state to prevent actuation of the switch by pivoting of the operating lever.

Description:
CROSS REFERENCE TO RELATED APPLICATIONS 
       [0001]    This application claims priority to and the benefit of DE202011108753.4, filed Dec. 6, 2011, the contents of which are incorporated herein in their entirety. 
       TECHNICAL FIELD 
       [0002]    Example embodiments generally relate to a hand-guided apparatus with an operating lever. 
         [0003]    BACKGROUND 
         [0004]    A hand-held apparatus with an operating lever customarily comprises one or more safety elements so that the operating lever can only be actuated by a previous or a simultaneous movement of the safety element. It should be prevented in this manner that the apparatus is inadvertently turned on. Such a safety element is especially required for electrical tools in order to avoid the danger of injuring a user. There are numerous different systems for safety elements in hand-guided apparatuses. 
         [0005]    For example, two safety elements can be provided, where the first safety element actuates the second safety element in order to release the operating lever. Usually, these safety elements are actuated in the same direction. However, this constellation is increasingly prohibited for electrically operated apparatuses. 
         [0006]    Furthermore, two safety elements can be provided that require a recess or a milled-out area in the handle or the housing of the apparatus. However, this reduces the stability of the handle or of the housing. 
       BRIEF SUMMARY OF SOME EXAMPLES 
       [0007]    Some example embodiments have the basic task of making available a hand-guided apparatus with an operating lever and an improved safety element. 
         [0008]    According to an example embodiment, a hand-guided apparatus is provided with at least one operating lever for actuating at least one function of the hand-guided apparatus, whereby
       the operating lever is constructed in an elongated manner and is pivotably attached to a housing of the hand-guided apparatus,   at least one switch for actuating the function is arranged in the housing,   at least one pivotable intermediate lever for mechanically actuating the switch is arranged in the housing,   the operating lever comprises a safety element that can be pretensioned and shifted along the longitudinal axis of the operating lever,   the operating lever and the intermediate lever can be mechanically coupled by shifting the safety element into a pretensioned state,   so that the switch can be actuated by the pivoting of the operating lever, and   the operating lever and the intermediate lever can be mechanically decoupled by shifting the safety element into a relaxed state,   so that the actuation of the switch is prevented by the pivoting of the operating lever.       
 
         [0017]    One aspect of some embodiments is the safety element, that can be pretensioned and that forms a part of the operating lever. As a result thereof, no separate opening is required in the housing for the safety element. The safety element does not have to be constructed as a separate switch. In the decoupled state the operating lever can not be overloaded. The actuations of the operating lever and of the safety element take place by movements in different directions, which corresponds to the safety standards. The operating lever with the safety element can be made available as a pre-mounted structural group so that the manufacture of the hand-guided apparatus is facilitated. 
         [0018]    A main part of the safety element is preferably arranged inside the operating lever in a shiftable manner. This makes possible a compact manner of construction of the operating lever with the safety element. 
         [0019]    Furthermore, an actuation part of the safety element can extend outward through a slot in the operating lever so that the safety element can be manually shifted by the actuation part. 
         [0020]    An elastic element is preferably arranged in the operating lever by means of which the safety element can be pretensioned. The elastic element is, for example, a spiral spring. 
         [0021]    In some cases, the intermediate lever is constructed as a two-armed lever, whereby a first lever arm is provided for actuating the switch and a second lever arm is provided for the coupling to the safety element. 
         [0022]    According to another example embodiment, a hand-guided apparatus is provided with at least one operating lever for actuating at least one function of the hand-guided apparatus, whereby
       the operating lever is constructed in an elongated manner and is pivotably attached to a housing of the hand-guided apparatus,   at least one switch for actuating the function is arranged in the housing,   at least one pivotable intermediate lever for mechanically actuating the switch is arranged in the housing,   the operating lever can be shifted along its axis of pivoting or its longitudinal axis,   the operating lever and the intermediate lever can be mechanically coupled by shifting the operating lever into a pretensioned state,   so that the switch can be actuated by the pivoting of the operating lever, and   the operating lever and the intermediate lever can be mechanically decoupled by shifting the operating lever into a relaxed state,   so that the actuation of the switch is prevented by the pivoting of the operating lever.       
 
         [0031]    One aspect of an example embodiment is the operating lever that can be pretensioned. As a result thereof, no safety element and therefore also no separate opening in the housing for the safety element are required. The operating lever can not be overloaded in the decoupled state. The releasing and the actuation of the operating lever take place by movements in different directions, which corresponds to the safety standards. 
         [0032]    In some cases, an elastic element is arranged in the housing with which element the operating lever can be pretensioned along its pivot axis or longitudinal axis. 
         [0033]    For example, the intermediate lever is constructed as a one-armed lever and the lever arm is provided for actuating the switch. 
         [0034]    In some cases, the operating lever and the intermediate lever have a common pivot axis. 
         [0035]    Further features, especially embodiments and advantages of the invention are subject matter of the subclaims. 
     
    
     
       BRIEF DESCRIPTION OF THE SEVERAL VIEWS OF THE DRAWING(S) The invention is explained in detail using some exemplary embodiments and with reference made to the attached drawings, in which: 
         [0036]      FIG. 1  shows a schematic lateral partial view in section of the hand-guided apparatus according to a first example embodiment of the invention, 
           [0037]      FIG. 2  shows a schematic exploded view of an operating lever and of an intermediate lever for the hand-guided apparatus in accordance with the first example embodiment of the invention, 
           [0038]      FIG. 3  shows a schematic lateral partial view in section of the hand-guided apparatus according to a second example embodiment of the invention, 
           [0039]      FIG. 4  shows another schematic lateral partial view in section of the hand-guided apparatus according to the first example embodiment of the invention, and 
           [0040]      FIG. 5  shows another schematic lateral partial view in section of the hand-guided apparatus according to the second example embodiment of the invention. 
       
    
    
     DETAILED DESCRIPTION 
       [0041]      FIG. 1  shows a schematic lateral partial view in section of the hand-guided apparatus according to a first embodiment of the invention. The hand-guided apparatus comprises a housing  10  with an elongated handle  12 . In this example the housing  10  and the handle  12  are constructed in one piece. Furthermore, an intermediate lever  16  and a switch are located in the housing  10 . An elongated operating lever  14  is pivotably attached to the housing  10 . The larger part of the operating lever  14  is located outside of the housing  10 . The operating lever  14  is arranged parallel to the handle  12  or forms an acute angle with it according to the state of pivoting. 
         [0042]    The switch  18  is located in the area of the housing  10 , to which the handle  12  is attached or into which the handle  12  empties. The switch  18  has a key  20  that can be actuated by pressing along the longitudinal axis of the handle  12 . In this embodiment the switch  18  is designed as an electrical switch. For example, the switch  18  can also be provided as a valve for liquids or gases. 
         [0043]    A safety element  22  is located on the operating lever  14 . The safety element  22  is constructed in one piece and comprises a main part  28  ( FIG. 2 ) and an actuating part  30 . The main part  28  of the safety element  22  is constructed in an elongated manner and is located inside the hollow operating lever  14 . The main part  28  can be shifted along its longitudinal axis inside the operating lever  14 . The actuating part  30  of the safety element  22  is located outside of the operating lever  14  and extends through a slot  40  that extends along the longitudinal axis of the operating lever  14 . Thus, a user can shift the safety element  22  inside of the operating lever  14  by moving the actuating part  30 . 
         [0044]    The intermediate lever  16  is pivotably attached in the housing  10 . The intermediate lever  16  is a two-armed lever and is constructed in an approximate L-shape. A first lever arm  24  is provided for actuating the key  20  on switch  18 . A second lever arm  26  ( FIG. 2 ) is actuated by a pivoting movement of the operating lever  14  so that the intermediate lever  16  itself executes a pivoting movement and the key  20  on switch  18  is pressed. 
         [0045]    The coupling between the operating lever  14  and the second lever arm  26  of the intermediate lever  16  takes place by the safety element  22 . By shifting the safety element  22  inside the operating lever  14 , the second lever arm  26  can be coupled to and decoupled from the safety element  22  and therewith to and from operating lever  14 . 
         [0046]    By shifting the safety element  22  toward the pivot axis of the operating lever  14  the second lever arm  26  lies on the safety element  22 . As a result, upon a pivoting movement of the operating lever  14  toward the handle  12  even the intermediate lever  16  is pivoted in such a manner that the key  20  on the switch  18  is pressed. 
         [0047]    On the other hand, if the safety element  22  is located on the end of the operating lever  14 , that is arranged opposite the pivot axis of the operating lever  14 , then upon a pivoting movement of the operating lever  14  toward the handle  12  the intermediate lever  16  is not moved. An elastic element  32  ( FIG. 2 ) is provided that presses the safety element  22  onto the end of the operating lever  14 , that is arranged opposite the pivot axis of the operating lever  14 . Thus, the force of the elastic element  32  must be overcome in order to push the safety element  22  toward the pivot axis and as a result to make possible the coupling between the operating lever  14  and the intermediate lever  16 . 
         [0048]    Moreover, the housing  10  and the operating lever  14  each have a projection  36 . The projections  36  are arranged oppositely and are provided for receiving another elastic element, in particular a spiral spring. This other elastic element brings it about that the operating lever  14  is pressed away from the handle  12 . In order to actuate the switch  18  the user must therefore pull the operating lever  14  against the action of this elastic element toward the handle  12 . 
         [0049]    If the actuating part  30  of the safety element  22  is pushed to the right in  FIG. 1  and the operating lever  14  is pivoted clockwise, then the intermediate lever  16  is also pivoted clockwise and the first lever arm  24  actuates the key  20  on the switch  18 . 
         [0050]      FIG. 2  shows a schematic exploded view of the operating lever  14  and of the intermediate lever  16  for the hand-guided apparatus in accordance with the first embodiment of the invention.  FIG. 2  shows the arrangement of the safety element  22  in the operating lever  14  and relative to the intermediate lever  16 . 
         [0051]    The cross section of the inner space in the operating lever  14  is slightly larger than the cross section of the main part  28  of the safety element  22 , so that the safety element  22  can be reliably shifted along the longitudinal axis of operating lever  14 . 
         [0052]    The elastic element is designed as spiral spring  32 , that is arranged inside the operating lever  14  as well as inside the main part  28  of the safety element  22 . The spiral spring  32  brings it about that the main part  28  of the safety element  22  and the intermediate lever  16  are decoupled. The safety element  22  is pressed to the left here by the spiral spring in  FIG. 2 . In order to actuate the switch  18  the user must therefore move the safety element  22  against the action of the spiral spring  32  and pull the operating lever  14  toward the handle  12 . 
         [0053]    In this example the operating lever  14  and the intermediate lever  16  have a common pivot axis. Alternatively, the operating lever  14  and the intermediate lever  16  can also have separate pivot axes. 
         [0054]      FIG. 3  shows a schematic lateral view in partial section of the hand-guided apparatus in accordance with a second embodiment of the invention. The same components and components with the same function have the same reference numerals as in the first embodiment. 
         [0055]    The hand-guided apparatus of the second embodiment also comprises the housing  10  with the elongated handle  12  that are constructed in one piece. The intermediate lever  16  and the switch  18  are located in the housing  10 . The elongated operating lever  14  is pivotably attached to the housing  10 , whereby the larger part of the operating lever  14  is located outside of the housing  10 . The operating lever  14  is arranged parallel to the handle  12  or forms an acute angle with it depending on the pivoting state. 
         [0056]    The switch  18  is located in the area of the housing  10  to which the handle  12  is attached or into which the handle  12  empties. The switch  18  comprises the key  20  that can be actuated by pressing on the longitudinal axis of the handle  12 . Even this switch  18  is constructed as an electric switch, whereby instead of the electric switch a valve for liquids or gases can also be provided. 
         [0057]    The intermediate lever  16  is pivotably attached in the housing  10  and constructed as a one-armed lever. The lever arm  24  is provided for actuating the key  20  on the switch  18 . The lever arm  24  is actuated by a pivoting motion of the operating lever  14  so that the key  20  on the switch  18  is pressed. 
         [0058]    In the second embodiment there are two possibilities for the coupling and decoupling between the operating lever  14  and the intermediate lever  16 . The coupling and decoupling are brought about by a shifting of the operating lever  14  either along its longitudinal axis or its pivot axis. In addition, there is the possibility of coupling and decoupling between the lever arm  24  of the intermediate lever  16  and the key  20  of the switch  18 . In the latter instance the operating lever  14  and the intermediate lever  16  are constructed singly or in one piece and the coupling and decoupling take place by the shifting of the operating lever  14  and the intermediate lever  16  about their common pivot axis. 
         [0059]    The one possibility for the coupling and decoupling of operating lever  14  and intermediate lever  16  can take place by shifting the operating lever  14  along its longitudinal axis.  FIG. 3  shows the decoupled state between operating lever  14  and intermediate lever  16  while the coupled state between the operating lever  14  and the intermediate lever  16  is not shown. If the operating lever  14  is pushed along its longitudinal axis in the direction of housing  10  and intermediate lever  16 , the mechanical coupling between the operating lever  14  and the intermediate lever  16  takes place so that the switch  18  can be actuated by the pivoting motion of the operating lever  14 . If the operating lever  14  is withdrawn along its longitudinal axis from the housing  10  and the intermediate lever  16 , the mechanical decoupling between the operating lever  14  and the intermediate lever  16  takes place in such a manner that the intermediate lever  16  is not entrained by the pivoting motion of the operating lever  14  and as a result the switch  18  can not be actuated. 
         [0060]    The other possibility for the coupling and decoupling between the operating lever  14  and the intermediate lever  16  and key  20  of the switch  18  takes place by an axial movement of the operating lever  14  along its pivot axis, i.e., vertically to the drawing plane of  FIG. 3 . This shifts the operating lever  14  in the lateral direction. If the operating lever  14  and the intermediate lever  16  are constructed in one piece with the lever arm  24  lever arm  24  would move past the key  20  in the decoupled state during the pivoting of the operating lever  14  so that the decoupling between the lever arm  24  and the key  20  takes place. On the other hand, if the operating lever  14  and the intermediate lever  16  with the lever arm  24  are constructed as separate parts, then the intermediate lever  16  for the lever arm  24  would not be entrained in the decoupled state during the pivoting of the operating lever  14 , so that the decoupling between operating lever  14  and the intermediate lever  16  takes place. An elastic element  38  is provided that counteracts the coupling between operating lever  14  and the intermediate lever  16  or between operating lever  14  with intermediate lever  16  and the key  20 . 
         [0061]    In order to actuate the switch  18  the user must therefore push the operating lever  14  axially along its pivot axis and subsequently pull it towards the handle  12 . 
         [0062]    In the described embodiments the user merely has to move the operating lever  14  in  FIG. 3  or the safety element  22  in  FIG. 2  forward, i.e., in the direction of the longitudinal axis of the operating lever  14  in order to actuate the cutting-in mechanism. As described above, the cutting-in mechanism can be alternately activated by shifting the operating lever  14  in the lateral direction. If the operating lever  14  is subsequently pulled to the handle  12 , no expenditure of force in the direction of the operating lever  14  is required. Otherwise, this would make the work more difficult for the user. 
         [0063]    In  FIG. 3  the intermediate lever  16  and the operating lever  14  are connected to one another by a small hook on the second lever arm  26 . In a similar manner, in  FIG. 2  the intermediate lever  16  and the safety element  22  are connected to one another by the small hook on the second lever arm  26 . The force for actuating the switch  18  causes a friction between the second lever arm  26  and the safety element  22  and between the operating lever  14  and the intermediate lever  16 . When the operating lever  14  is released, in  FIG. 3  the operating lever  14  itself jumps back and in  FIG. 2  the safety element  22  jumps back. 
         [0064]      FIG. 4  shows another schematic lateral view in partial section of the hand-guided apparatus in accordance with the first embodiment of the invention. The hand-guided apparatus comprises the housing  10  with the handle  12 , the operating lever  14 , the safety element  22  with the main part  28  and with the actuating part  30 , comprises the intermediate lever  16  with the first lever arm  24  and with the second lever arm  26 , comprises the switch  18  with the key  20  and comprises the two projections  36 . The actuating part  30  and with the second lever arm  26 , comprises the switch  18  with the key  20  and comprises the two projections  36 . The actuating part  30  extends through the slot  40 , that extends along the longitudinal axis of the operating lever  14 . The user can push the safety element  22  inside the operating lever  14  by moving the actuating part  30 . 
         [0065]    In contrast to  FIG. 1 ,  FIG. 4  shows the interior of the operating lever  14 . The spiral spring  32  brings it about that the safety element  22  and main part  28  and actuating part  30  are pressed to the left in  FIG. 4 . In order to actuate the switch  18  the user must move the safety element  22  against the force of the spiral spring  32  with the actuating part  30  and pull the operating lever  14  toward the handle  12 , during which the actuating part  30  is shifted inside the slot  40 . 
         [0066]    In particular,  FIG. 4  shows the coupling between the safety element  22  and the second lever arm  26  in detail. The safety element  22  and the second lever arm  26  are constructed complementary to one another in sections at the coupling point, so that in the coupled state the safety element  22  and the second lever arm  26  are engaged. In this example the safety element  22  and the second lever arm  26  each have a projection and an undercut. 
         [0067]      FIG. 5  shows another schematic, lateral view in partial section of the hand-guided apparatus in accordance with the second embodiment of the invention. In this example the operating lever  14  and the intermediate lever  16  are constructed as separate parts, whereby the coupling and the decoupling take place between the operating lever  14  and the intermediate lever  16 . 
         [0068]      FIG. 5  also shows the coupling between the operating lever  14  and the intermediate lever  16  in detail. The operating lever  14  and the intermediate lever  16  are constructed complementary to one another in sections at the coupling point so that in the coupled state the operating lever  14  and the intermediate lever  16  are engaged. Even in this example the operating lever  14  and the intermediate lever  16  each have a projection and an undercut. 
         [0069]    In particular, the hand-guided apparatus can be an electrical tool. An electrical hedge cutter, an electrical chain saw or a manual circular saw are cited as examples. Likewise, the hand-guided apparatus can be an injection device in which the switch  18  is designed as a valve.