Abstract:
The invention is based on an auxiliary handle device, in particular for hand-held power tools, comprising a fastening unit which comprises at least one fastening mechanism. It is proposed that the fastening mechanism is provided in an axial direction of a fastening axis in order to achieve a positive connection.

Description:
CROSS-REFERENCE TO RELATED APPLICATION 
     This application is a 35 USC 371 application of PCT/EP 2007/057148 filed Jul. 12, 2007. 
     BACKGROUND OF THE INVENTION 
     1. Field of the Invention 
     The invention is based on an auxiliary handle device. 
     2. Description of the Prior Art 
     The invention is based on an auxiliary handle device, in particular for hand-held power tools, with an attaching device that has at least one fastening mechanism. 
     SUMMARY OF THE INVENTION 
     The invention is based on an auxiliary handle device, in particular for hand-held power tools, with an attaching device that has at least one fastening means. 
     According to one proposal, the fastening mechanism is provided for producing a form-locked connection in an axial direction of a fastening axis, thus achieving an efficient securing of an auxiliary handle in the axial direction. This advantageously prevents the auxiliary handle from slipping in the axial direction, for example in the event that a tool jams during operation of the hand-held power tool. The auxiliary handle device is particularly provided for the fastening of the auxiliary handle to a hand-held power tool such as a drilling and/or hammering hand-held power tool, e.g. an impact drill, so that the fastening axis of the fastening device corresponds to a tool axis of the hand-held power tool, in particular a drilling axis. In this context, an “axial direction of a fastening axis” is understood to be a direction along the fastening axis. 
     According to another proposal, the fastening device has at least one additional fastening mechanism for producing a form-locked connection in a circumference direction of the fastening axis, thus making it possible, in addition to a securing of an auxiliary handle to a hand-held power tool in the axial direction of the fastening axis, to also achieve a securing of the auxiliary handle in the circumference direction of the fastening axis. The fastening mechanism for producing the form-locked connection in the circumference direction of the fastening axis is situated and/or embodied in a location or way that differs from that of the fastening mechanism for producing the form-locked connection in the axial direction of the fastening axis. A “circumference direction of the fastening axis” is understood here to be a direction that is oriented around the fastening axis. 
     According to another proposal, the fastening mechanism for producing a form-locked connection in the axial direction of the fastening axis has a rib-shaped fastening element that makes it possible to achieve a rugged fastening mechanism and an efficient securing of an auxiliary handle in the axial direction. Preferably, a main extension direction of the rib-shaped fastening element is oriented perpendicular to the fastening axis so that it is possible to achieve a maximal securing and/or fastening area for the securing in the axial direction. In this instance, the rib-shaped fastening element can be situated in a receiving region of the auxiliary handle or can be coupled to a component of the hand-held power tool provided for the fastening of the auxiliary handle. In addition, the rib-shaped fastening element can be constituted by a pin-shaped or rod-shaped component, a stamped sheet metal component, or other components deemed suitable by those skilled in the art. 
     According to another proposal, the rib-shaped fastening element is situated inside an auxiliary handle, thus making it possible to achieve a convenient mounting of the auxiliary handle, in particular a play-free mounting. In addition, it is advantageously possible to save on additional components, space, assembly complexity, and costs if the rib-shaped fastening element is embodied as integrally joined to the auxiliary handle. The rib-shaped fastening element in this instance can be press-fitted into the auxiliary handle, injection-molded into it, or fastened to the auxiliary handle in another way deemed suitable by those skilled in the art. 
     For producing a form-locked connection in the axial direction of the fastening axis, the fastening mechanism advantageously has a groove-shaped recess that makes it possible to achieve a simple and in particular tool-free detent engagement of a fastening mechanism that corresponds to it. Preferably, a main extension direction of the groove-shaped recess is oriented perpendicular to the fastening axis. In particular, the groove-shaped recess can extend in the circumference direction of the fastening axis. 
     In addition, a particularly compact embodiment of a hand-held power tool can be achieved if the groove-shaped recess is situated in a spindle neck of the hand-held power tool. By means of a fastening mechanism that corresponds to the groove-shaped recess and is situated on the auxiliary handle, e.g. a rib-shaped fastening element, it is also possible, through the addition of a detent mechanism of the fastening mechanism, to produce a haptic feeling of safety for an operator of the hand-held power tool. 
     It is possible to achieve a rugged securing if the fastening mechanism for producing a form-locked connection in the circumference direction of the fastening axis has at least one raised area. The raised area can be situated on an auxiliary handle or on a component of a hand-held power tool that is provided for the fastening of the auxiliary handle. 
     An attachment of the auxiliary handle that is particularly convenient and easy for an operator of the hand-held power tool can be achieved if the raised area is situated on a spindle neck of the hand-held power tool. In this case, the raised area is suitably embodied as integrally joined to the spindle neck of the hand-held power tool, thus enabling savings on additional components, space, assembly complexity, and costs. In a particularly advantageous embodiment, the raised area is bar-shaped and is coupled to a housing of the hand-held power tool. 
     The fastening mechanism for producing a form-locked connection in the circumference direction of the fastening axis advantageously has at least one recess, thus making it possible to achieve a simple, form-locked securing to corresponding fastening mechanism, e.g. raised areas, in the circumference direction. In this case, the fastening mechanism with the recesses can be situated on a component of a hand-held power tool that is provided for the fastening of the auxiliary handle and in a particularly advantageous embodiment, can be situated on an auxiliary handle. 
     According to a proposal in another embodiment of the invention, the auxiliary handle device has a receiving device of an auxiliary handle that is composed of at least two parts, thus making it possible to achieve a particularly convenient, structurally simple attachment of the auxiliary handle to a hand-held power tool, in particular to a spindle neck of an impact drill. In addition, a particularly advantageous play-free insertion of the spindle neck into the receiving device can be achieved in that one part of the receiving device is provided for the axial securing and another part of the receiving device is provided for the insertion. In this context, a “receiving device” is understood to be a device of an auxiliary handle that is provided for receiving a subregion of a hand-held power tool, in particular a spindle neck. 
     According to another proposal, the auxiliary handle device includes a first and second component of the auxiliary handle, which engage with each other in the assembled state. This makes it possible to achieve a particularly stable receiving device of the auxiliary handle and to achieve a stable, secure attachment to the hand-held power tool. 
     According to a particularly advantageous embodiment, this can be achieved in a structurally simple fashion if at least one subregion of one of the components of the auxiliary handle is embodied as slot-like. Preferably, a slot-like embodiment of one of the components is oriented perpendicular to the fastening axis. 
     A structurally simple, form-locked reciprocal engagement of the two components of the receiving region of the auxiliary handle can be achieved if at least one subregion of a component of the auxiliary handle has a cavity. In this context, a “cavity” is understood to be a hollow space that is situated on the interior of the component and is open to the outside at a maximum of two sides. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
       Other advantages ensue from the following description taken in conjunction with the drawings, in which: 
         FIG. 1  shows a hand-held power tool with an auxiliary handle device, 
         FIG. 2  shows a spindle neck of the hand-held power tool from  FIG. 1 , 
         FIG. 3  is a partial section through the auxiliary handle from  FIG. 1  with a receiving device composed of two parts, 
         FIG. 4  shows a first component of the receiving device from  FIG. 3 , 
         FIG. 5  shows a second component of the receiving device from  FIG. 3 , 
         FIG. 6  shows the auxiliary handle in an open state, 
         FIG. 7  shows the auxiliary handle in a closed state, 
         FIG. 8  shows an exploded view of an alternative auxiliary handle, and 
         FIG. 9  is a longitudinal section through the auxiliary handle from  FIG. 8  in the assembled state. 
     
    
    
     DESCRIPTION OF THE PREFERRED EMBODIMENTS 
       FIG. 1  shows a hand-held power tool  12  embodied in the form of a drilling and/or impact drilling machine. The hand-held power tool  12  includes a tool holder  52  that can be driven by means of a drive unit, not shown in detail, and a main handle  54  situated at the end of the hand-held power tool  12  oriented away from the tool holder  52 . An auxiliary handle  32  is situated before the tool holder  52  in the axial direction  28 , along a drilling axis  22  of the hand-held power tool  12 . The auxiliary handle  32  is situated on a spindle neck  44  of the hand-held power tool  12 . The auxiliary handle  32  can be fastened to the spindle neck  44  of the hand-held power tool  12  by means of an auxiliary handle device  10  that includes a fastening device  14 . 
       FIG. 2  shows a partial section through the drilling and/or impact drilling machine shown in  FIG. 1 , with the spindle neck  44  for accommodating the auxiliary handle  32 . The spindle neck  44  has a cylinder-like form and is oriented along the drilling axis  22  of the drilling and/or impact drilling machine. The fastening axis corresponds to the drilling axis  22  of the drilling and/or impact drilling machine. The fastening device  14  is situated on the spindle neck  44 , which has a fastening means  16  for producing a form-locked connection in the circumference direction  20  of the fastening axis and another fastening means  26  for producing a form-locked connection in the axial direction  28  of the fastening axis. The fastening means  16  for producing the form-locked connection in the circumference direction  20  has four bar-shaped raised areas  46  that are distributed around the spindle neck  44  in the circumference direction  20 . The four bar-shaped raised areas  46  are spaced apart from one another by 90° in the circumference direction  20  and are integrally joined to the spindle neck  44 . In addition, the bar-shaped raised areas  46  are situated on an edge region  58  of the spindle neck  44  that is oriented away from the tool holder  52  and situated adjacent to a housing  38  of the hand-held power tool  12 . 
     The fastening means  26  for producing the form-locked connection in the axial direction  28  of the fastening axis has a groove shaped recess  42  that extends in the circumference direction  20  around the spindle neck  44  of the hand-held power tool  12 . The groove-shaped recess  42  extends in an annular fashion around the entire spindle neck  44 . It is also essentially conceivable, though, for the groove-shaped recess  42  to extend over a limited partial region in the circumference direction  20  on the spindle neck  44 . In the direction toward the tool holder  52  along the fastening axis, the groove-shaped recess  42  is situated after the four bar-shaped raised areas  46 . The groove-shaped recess  42  is also spaced apart from the four bar-shaped raised areas  46  on the spindle neck  44 . 
       FIG. 3  shows a partial section through the auxiliary handle  32 . The auxiliary handle  32  includes a receiving device  30 , which is composed of two parts, and the fastening device  14  of the auxiliary handle device  10 , which has a fastening means  18  for producing the form-locked connection in the circumference direction  20  of the fastening axis and a fastening means  24  for producing a form-locked connection in the axial direction  28  of the fastening axis. 
     A first component  34  of the auxiliary handle  32  includes a handle element  64  and a semicircular receiving element  66  of the receiving device  30  for receiving the spindle neck  44  of the drilling and/or impact drilling machine ( FIG. 4 ). The receiving element  66  is integrally joined to the handle element  64  and is open at an end oriented away from the handle element  64 . An edge region  68  of the semicircular receiving element  66  is adjoined by a molded region  60  for accommodating the measuring device. The receiving element  66  here encompasses a receiving region  70  with a diameter K in a semicircular fashion. 
     The receiving element  66  of the first component  34  is equipped with the fastening means  18  in order to secure the auxiliary handle  32  to the spindle neck  44  of the drilling and/or impact drilling machine in the circumference direction  20  of the fastening axis. The fastening means  18  is composed of recesses  48  spaced uniformly apart from one another, which are arranged in the circumference direction  20  on a side of the receiving element  66  oriented toward the receiving region  70 . The recesses  48  here extend along the fastening axis on a subregion of the semicircular receiving element  66 . In order to secure the auxiliary handle  32  in the axial direction  28  of the fastening axis, the receiving element  66  is equipped with the fastening means  24  for producing a form-locked connection in the axial direction  28  of the fastening axis, which fastening means  24  is constituted by a rib-shaped fastening element  50  and is press-fitted into the receiving element  66 . In this case, the rib-shaped fastening element  50 , which is embodied in the form of a pin, protrudes into the semicircular receiving region  70  of the receiving element  66 . A main extension direction  72  of the rib-shaped fastening element  50  is oriented perpendicular to the fastening axis ( FIG. 4 ). 
     As shown in  FIG. 5 , a second component  36  has a subregion  74 , which is provided for engaging in the first component  34 , and a circular receiving element  76  for accommodating the spindle neck  44  of the drilling and/or impact drilling machine. The subregion  74  and the circular receiving element  76  here are embodied as integrally joined to each other. The receiving element  76  forms a circular receiving region  78  with a diameter K′ that is equal to the diameter K of the first component  34 . The molded region  60  for accommodating the measuring device is situated in an edge region  80  of the receiving element  76 , opposite from the subregion  74 . 
     On the lateral molded region  60 ,  61  of the first component  34  and of the second component  36 , respectively, the auxiliary handle  32  also has a receiving region  62  for a measuring device that is not shown in detail, which is provided for measuring and/or detecting a drilling hole depth in a drilling procedure carried out with the drilling and/or impact drilling machine ( FIG. 3 ). The measuring device here is advantageously affixed to the auxiliary handle  32  with a form-locked assembly of a first component  34  and second component  36  of the auxiliary handle  32  ( FIGS. 6 and 7 ). 
       FIGS. 6 and 7  show the form-locked reciprocal engagement of the first component  34  and the second component  36  of the auxiliary handle  32 . To this end, a subregion encompassed by the handle element  64  of the first component  34  is provided on the inside with a cavity  82  that is provided for accommodating the second component  36  ( FIGS. 4 and 6 ). The second component  36  is embodied as slot-shaped in the subregion  74 , in a region of the receiving element  76  oriented toward the subregion  74  ( FIG. 3 ) so as to enable a form-locked engagement in the first component  34 . A slotted region  84  ( FIG. 3 ) of the second component  36  is oriented perpendicular to the fastening axis. When all auxiliary handle  32  is mounted onto the spindle neck  44  of the drilling and/or impact drilling machine, the second component  36  is inserted perpendicular to the fastening axis with the subregion  74  at the front, into the semicircular receiving region  70  and then into the cavity  82  of the first component  34  depicted with dashed lines in  FIG. 6 . In this case, the second component  36  is inserted into the first component  34  far enough that an essentially complete circular diameter K′ of the second component  36  remains ( FIG. 6 ). The circular diameter K′ of the receiving region  78  is matched to a cross section of the spindle neck  44  so that the auxiliary handle  32  can be guided onto the spindle neck  44  virtually without play. In order to hold the second component  36  in position relative to the first component  34  while the auxiliary handle  32  is being guided into place, the first component  34  and the second component  36  are screwed to each other by means of a screw connection that is not show in detail. The auxiliary handle  32  with the first component  34  and the second component  36  is guided with the side with the recesses  48  toward the front, past the tool holder  52  onto the spindle neck  44  until the recess  48  and the bar-shaped raised areas  46  come into form-locked engagement with each other. To this end, the second component  36  is embodied as shorter than the first component  34  by the span length of the recesses  48  in the axial direction  28  ( FIG. 3 ). The auxiliary handle  32  here can be attached in different radial orientations by means of the four bar-shaped raised areas  46  on the spindle neck  44  and the recesses  48  on the auxiliary handle  32 . Then the first component  34  and the second component  36  are clamped to each other by means of the screw connection so that the rib-shaped fastening element  50  engages in a form-locked fashion in the groove-shaped recess  42  provided for it in the spindle neck  44  while the first component  34  and second component  36  are connected to each other in a form-locked fashion ( FIG. 7 ). In order to detach the auxiliary handle  32 , the screw connection is loosened until the rib-shaped fastening element  50  is freed from the groove-shaped recess  42  so that the auxiliary handle  32  can first be slid axially and can then be shifted as needed in the circumference direction  20 . 
       FIGS. 8 and 9  show an alternative embodiment of the auxiliary handle  32 . For features and functions that remain the same, the reader can refer to the description of the exemplary embodiment in  FIGS. 1 through 7 . Components and features that essentially correspond have basically been labeled with the same reference numerals. The following description of  FIGS. 8 and 9  will be essentially limited to the differences in relation to the exemplary embodiment in  FIGS. 1 through 7 . 
     The second component  36  has the fastening means  18  for producing a form-locked connection in the circumference direction  20 . The recesses  48  extend along a subregion  56  of the receiving element  76  of the second component  36  in the circumference direction  20 ; in the assembled state, the subregion  56  with the recesses  48  transitions into the recesses  48  of the first component  34 . In addition, the rib-shaped fastening element  50  of the first component  34  is composed of a stamped sheet metal part. 
     The auxiliary handle  32  in  FIGS. 8 and 9  has a third component  86  for clamping the first component  34  to the second component  36 . To this end, the third component  86  has a handle element  88  that is inserted into the first component  34  in rotatable fashion and is screwed to the second component  36  by means of a threaded rod  90  shown in  FIG. 9 . For this purpose, the subregion  74  of the second component  36  includes a recess  92  into which a nut  94  is inserted. The nut  94  is provided with a rotation prevention means and is integrated in a form-locked fashion into a plastic wall of the subregion  74  of the second component  36 . In addition, the cavity  82  of the first component  34  contains a spring  96  that is situated around the threaded rod  90  of the third component  86  and is prestressed when the auxiliary handle  32  is in the assembled state. If the screw connection to the second component  36  is detached by rotation of the third component  86 , then a spring force of the spring  96  causes the second component  36  to be pushed out of the first component  34  and the rib-shaped fastening element  50  is released from the groove-shaped recess  42  of the spindle neck  44 ; the auxiliary handle  32  can then be removed from the spindle neck  44  of the hand-held power tool  12 . 
     It is also essentially conceivable for the rib-shaped fastening element  50  to be spring-loaded so that when the auxiliary handle  32  is mounted in place, the rib-shaped fastening element  50  engages in detent fashion in the groove-shaped recess  42  of the spindle neck  44  as soon as the auxiliary handle  32  is connected in form-locked fashion to the spindle neck  44  in the circumference direction  20 . 
     The foregoing relates to the preferred exemplary embodiments of the invention, it being understood that other variants and embodiments thereof are possible within the spirit and scope of the invention, the latter being defined by the appended claims.