Patent Publication Number: US-7905223-B2

Title: Guide cart and power tool with guide a cart

Description:
BACKGROUND OF THE INVENTION 
     The invention concerns a guide cart for a hand-held power tool with a driven tool, wherein the guide cart has at least one fixation means for releasable fixation of the power tool on the guide cart, wherein the fixation means is secured on a pivot device that is pivotable between an open position and a fixation position. The invention also relates to a power tool with a guide cart wherein the power tool has a housing in which a drive motor is arranged that drives in rotation a rotatably supported tool and wherein the power tool has at least one handle for manually guiding the power tool, wherein the guide cart has at least one fixation means for a releasable fixation of the power tool on the guide cart, and wherein the fixation means is secured on a pivot device that is pivotable between an open position and a fixation position. 
     U.S. Pat. No. 6,478,666 B1 discloses a guide cart for a hand-held power tool, namely for a cut-off machine, wherein, for fixation on the guide cart, the cut-off machine is inserted into an upper and a lower receptacles and is secured by a pivotable lever. The fixation of the cut-off machine by means of a pivotable lever enables a simple and quick fixation of the cut-off machine on the guide cart. 
     Such hand-held power tools usually have vibration damping elements with which the handles of the power tool are vibration-decoupled from the drive motor and the tool. When the power tool is secured on the guide cart on a component that is vibration-decoupled relative to the tool, an imprecise guiding action of the tool may result. The tool can vibrate as a result of the vibrations occurring in operation. These vibrations cannot be compensated as a result of the vibration decoupling of the tool relative to the guide cart. 
     SUMMARY OF THE INVENTION 
     It is an object of the invention to provide a guide cart for a hand-held power tool with which an excellent guiding action of the power tool is enabled. A further object of the invention resides in providing a power tool with a guide cart that can be guided excellently. 
     This object is solved by a guide cart and a power tool with a guide cart in that the pivot device has at least one support for supporting the tool of the power tool in the fixation position of the pivot device. 
     In that the pivot device of the guide cart not only has at least one fixation means for fixation of the power tool but also at least one support for supporting the tool of the power tool, a direct support action of the tool relative to the guide cart is achieved. The support of the tool in this connection is a support of the bearing of the tool so that the rotating movement of the tool is not impaired. By means of the support the cutting forces resulting in operation can be compensated partially so that a beneficial force introduction into the guide cart is provided. In that the fixation means as well as the support are arranged on the pivot device, the pivot movement of the pivot device causes the fixation means as well as the support to be arranged on the power tool. In this way, a simple and fast fixation of the power tool on the guide cart is achieved. A separate fixation of a support for the tool is not required. 
     In hand-held power tools, in particular cut-off machines, the tool, i.e., in particular the cut-off wheel, can be secured in different positions on the power tool. In order to enable in any position of the tool a supporting action, it is provided that the support is releasably secured on a transverse bracket wherein the transverse bracket has means enabling securing of the support on the transverse bracket in at least two positions. When retooling the power tool, in the case of a cut-off machine e.g. moving the cut-off wheel from a central position into an external position on an extension arm of the cut-off machine, the support can also be adjusted to a different position so that it is ensured that, when the pivot device is pivoted into the fixation position, the support will come to rest against a component connected to the tool or the bearing of the tool and supports the tool in this way. 
     Advantageously, the guide cart has at least one locking means for locking the pivot device in the fixation position. Advantageously, the locking means is secured on the pivot device and interacts in the locked position with the power tool and provides a fixation means for the power tool. The locking means thus fulfills two functions. It ensures on the one hand locking of the pivot device and on the other hand it secures the locking means in the locked position of the power tool on the guide cart. Advantageously, the locking means is a locking lever that is pivotably secured on the pivot device. Advantageously, the locking lever is pivotable about a pivot axis that is approximately parallel to the pivot axis of the pivot device. 
     It is provided that the pivot device is pivotable about a pivot axis that is transversely positioned relative to the traveling direction of the guide cart. Advantageously, the pivot axis of the pivot device is approximately horizontal. By means of the approximately horizontal position of the pivot axis of the pivot device, the pivot device can be pivoted across the power tool. As a result of this pivot direction, the support for the tool can be moved in a simple way into its position. 
     In order to achieve a simple insertion of the power tool on the guide cart, it is provided that the guide cart has a holder for the power tool wherein the holder is designed such that the power tool in the open position of the pivot device is insertable into the holder and removable from the holder. For fixation of the power tool on the guide cart, the power tool must only be inserted into the holder in the open position of the pivot device and, subsequently, the pivot device must be pivoted into the fixation position. The locking lever is pivoted for locking. Further measures for the fixation of the power tool on the guide cart are not required. 
     Expediently, the holder comprises at least one holding pin. The power tool can be placed in a simple way onto a holding pin. The holding pin secures the power tool in all radial directions of the holding pin. An additional fixation must be provided only in the longitudinal direction of the holding pin. This fixation can be realized by means of the fixation means arranged on the pivot device. For this purpose, it is provided that the pivot device and the holder define a receiving space for the power tool and that at least one fixation means of the pivot device is arranged on the side of the receiving space opposite the holding pin. The fixation means that is positioned opposite the holding pin prevents that the power tool will slip off the holding pin in the longitudinal direction of the holding pin. In all other directions the power tool is secured by the holding pin. In this way, a simple configuration is provided. 
     Advantageously, the pivot device comprises a bow that extends across the receiving space for the power tool in the fixation position. The bow can be of a simple design. On the bow all fixation means and all locking means can be secured. The bow moreover can ensure the accessibility of further operating elements of the power tool. It is provided that the pivot device is supported on the side of the receiving space for the power tool that is positioned to the rear in the traveling direction of the guide cart. The pivot device is then pivoted forwardly, i.e., usually toward the tool of the power tool. 
     Advantageously, the holder is provided on a base plate and comprises at least one lateral guide for the power tool. The lateral guide facilitates insertion of the power tool into the holder. An additional securing action of the position of the power tool is achieved. Advantageously, the pivot device is supported on the base plate and forms together with the base plate a C-shaped frame. The frame-like configuration leads to a stable design and excellent introduction of forces of the power tool into the guide cart. The C-shaped frame can be realized in a simple way and with only a few components so that a simple configuration results. 
     Advantageously, the pivot device has at least one actuator for an operating element of the power tool. When forwardly pivoting the pivot device, the actuator for the operating element of the power tool can thus also be pivoted into a position for operating the operating element. An additional fixation of the actuator on the power tool is thus not required. In particular, an actuator is supported pivotably about a pivot axis that extends in the travel directions of the guide cart. In this way, the actuator can be pivoted against the power tool laterally and can actuate the operating element. 
     For a power tool with a guide cart wherein the power tool has a housing in which a drive motor is arranged that rotatingly drives a tool that is rotatably supported and wherein the power tool has at least one handle for manually guiding the power tool, wherein the guide cart has at least one fixation means for a releasable fixation of the power tool on the guide cart and wherein the fixation means is secured on a pivot device that is pivotable between an open position and a fixation position, it is provided that the pivot device has at least one support that supports the tool of the power tool in the fixation position of the pivot device. 
     By supporting the tool, the cutting forces resulting in operation can be compensated and introduced directly into the guide cart. By arranging the support on the pivot device, the pivot device upon pivoting of the pivot device can be moved toward the tool so that a separate mounting of the support is not required. In this way, the power tool can the secured in a simple way on the guide cart with only a few manipulations. 
     It is provided that the handle is supported so as to be vibration-decoupled relative to the drive motor of the power tool and that a fixation means of the pivot device in the fixation position interacts with the handle. In that the fixation means interacts with the handle, a force introduction into the power tool can be achieved that is similar to the force introduction in manual operation. In manual operation the forces are primarily introduced through the handle. In this way, an excessive loading of other components, in particular housing components, is avoided. The handle that interacts with the fixation means is in particular a grip pipe. 
     Advantageously, the guide cart has a locking lever that is pivotably supported on the pivot device. In particular, the locking lever interacts with the grip pipe of the power tool. Advantageously, the locking lever has a receptacle for the grip pipe; the receptacle locks on the grip pipe in the locked position of the locking lever. In that the locking lever locks on the grip pipe, a simple and safe locking action of the pivot device is provided. The pivot device can be locked quickly and easily on the grip pipe. Advantageously, the locking lever is pivotably supported about a pivot axis that extends approximately parallel to the pivot axis of the pivot device. The pivot axis is thus also positioned parallel to the longitudinal direction of the grip pipe so that pivoting of the locking lever is possible in a simple way. 
     It is provided that the guide cart has a base plate on which a holder for the power tool is provided wherein the pivot device and the base plate together with the grip pipe define a closed frame when the pivot device is in the fixation position. The closed frame comprised of the grip pipe, the base plate, and the pivot device enables a direct introduction of the cutting forces into the guide cart. As a result of the closed configuration a stable and simple construction is provided. In that the grip pipe of the power tool is utilized in order to provide a closed frame, the configuration of the guide cart is simplified. The guide cart has minimal weight. Advantageously, the holder comprises at least one holding pin onto which the power tool is pushed. In this way, the power tool can be simply inserted into the holder or can be simply removed from the holder. The holding pin is advantageously arranged adjacent to a lower section of the grip pipe and the locking lever engages in particular the opposite upper section of the grip pipe. In this way, the grip pipe is secured with opposite sections on the guide cart. Forces of the power tool can be dissipated directly into the guide cart. In this way, the forces acting on the housing of the power tool can be kept at a minimum. 
     Advantageously, the pivot device has a fixation means resting against the power tool on the side of the power tool opposite the holding pin. In this way, it can be prevented that the power tool can slip accidentally off the holding pin. The fixation means is pivoted into engagement in particular together with the pivot device. 
     It is provided that the pivot device has a bow that extends above the power tool approximately parallel to the longitudinal center axis of the power tool. Advantageously, the power tool has a handle that extends in the direction of the longitudinal center axis of the power tool. The handle is in particular an upper handle that extends on the top side of the power tool. However, it can also be provided that the handle is a rear handle. The longitudinal center axis of the bow has in plan view onto the power tool in particular a spacing relative to the center axis of the handle. It is provided that on the handle extending in the direction of the longitudinal center axis of the power tool an operating element for the power tool is arranged and that the bow has an actuator for the operating element that is pivotably supported about a pivot axis that is approximately parallel to the longitudinal center axis of this handle and, in a plan view onto the power tool, is positioned adjacent to this handle. By the lateral displacement between the bow and the handle or the lateral displacement between the pivot axis of the actuator for the operating element and the handle, the actuator can pivot laterally into engagement relative to the operating element. When pivoting the pivot device, the actuator is positioned adjacent to the handle and does not impair the pivoting action for engagement and the pivoting action for disengagement. In this way, the actuator can be secured fixedly on the pivot device. A separate fixation of the actuator for the operating element is not required. 
     Advantageously, on the handle extending in the direction of the longitudinal center axis of the power tool a locking device for the operating element is arranged. The pivot device has advantageously an actuator for the locking device that actuates the locking device in the fixation position of the pivot device. This actuator is also arranged on the locking device when the pivot device is pivoted so that in this case there are also no additional mounting steps required. After pivoting and locking of the pivot device the power tool is immediately operative. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         FIG. 1  shows a schematic perspective illustration of a guide cart with power tool arranged thereon. 
         FIG. 2  is a perspective detail illustration of the position of the bow of the guide cart on the power tool. 
         FIG. 3  is a detail side view of the bow with locking lever and support. 
         FIG. 4  is a detail illustration of a cut-off machine on the guide cart in a side view. 
         FIG. 5  is a perspective illustration of base plate and bow of the guide cart. 
         FIG. 6  is a schematic plan view of the guide car. 
         FIG. 7  is a schematic illustration of the connection of the grip pipe on the housing of the cut-off machine. 
         FIG. 8  is a schematic plan view onto the transverse bracket of the guide cart. 
     
    
    
     DESCRIPTION OF PREFERRED EMBODIMENTS 
     On the guide cart  1  illustrated in  FIG. 1  a hand-hand power tool, i.e., a cut-off machine  17 , is secured. The invention can also be utilized in connection with a guide cart for a different hand-held power tool. The cut-off machine  17  has a housing  18  on which handles (an upper handle  19  and a grip pipe  22 ) are secured. By means of the upper handle  19  and the grip pipe  22  the cut-off machine  17  can be manually guided by the operator. In order to be able to produce straight cuts in a simple way, the cut-off machine  17  is secured on the guide cart  1 . The guide cart  1  has a front wheel  2  and two rear wheels  3  by means of which the guide cart  1  is pushed across the ground in the traveling direction  61 . 
     The guide cart  1  has a base frame  9  on which the two rear wheels  3  are secured. The front wheel  2  is connected to the base frame  9  by an adjusting device  4  that comprises a first stay  5 , a second stay  6 , as well as a locking strip  7 . By means of the locking strip  7  the angle defined by the stays  5  and  6  can be changed. This causes the spacing between the front wheel  2  and the lower part of the base frame  9  to which the cut-off machine  17  is secured to be changed. By means of the adjusting device  4  the cutting depth of the cut-off machine  17  can thus be adjusted. 
     The cut-off machine  17  has a cut-off wheel  30  that is rotatingly driven about axis of rotation  32 . The cut-off wheel  30  is partially covered about its circumference by a protective cover  31 . The protective cover  31  extends on a side of the cut-off wheel  30  facing away from the ground. A splash guard  8  is arranged on the base frame  9  of the guide cart  1  behind the cut-off wheel  30  in the traveling direction  61 . 
     On the upwardly projecting side of the base frame  9  a holder  10  is secured on which a water tank  11  is detachably arranged. On the upwardly projecting end of the base frame  9  a handle bar  12  is secured on a pivot bearing  13 . The pivot bearing  13  can be released or secured by means of a fixation lever  14 . In this way, the height of a handle bar section  15  arranged on the handle bar  12  can be adjusted in order to enable economic working for the operator. On the handle bar section  15  an actuating grip  16  is provided which enables actuation of a throttle lever  20  of the cut-off machine  17  from the handle bar section  15 . For this purpose, on the throttle lever  20  a throttle lever actuator  21  of the guide cart  1  is provided whose function will be explained in the following in more detail. 
     For the fixation of the cut-off machine  17  on the guide cart  1  a C-shaped frame is arranged on the guide cart  1  and is illustrated in  FIG. 5  in a perspective view. As shown in  FIGS. 1 and 5 , the C-shaped frame has a base plate  25  on which a bow  26  is pivotably supported about pivot axis  48 . As shown in  FIG. 1 , the base plate  25  rests on the base frame  9  of the guide cart  1 . The baseplate  25  can be screwed onto the base frame  9 . The bow  26  is pivotable between the fixation position  63  illustrated in solid lines in  FIG. 1  and the open position  62  illustrated in dashed lines in  FIG. 1 . For this purpose, a pivot bearing  27  is provided on the base plate  25  on the rearward side of the base plate  25  in the traveling direction  61 . On the bow  26  a bearing plate  28  for the throttle lever actuator  21  is secured. Moreover, on the bow  26  a locking lever  29  is pivotably supported as a fixation means. The locking lever  29  interacts in the locked position illustrated in  FIG. 1  with the grip pipe  22 . Moreover, on the bow  26  a support  33  for the protective cover  31  of the cut-off wheel  30  is secured. By means of the protective cover  31  the cut-off wheel  33  is thus supported relative to the guide cart  1 . The bow  26  and the elements secured on the bow  26  form a pivot device. Instead of the bow  26  the pivot device can also be comprised of other pivotably supported components such as plates, supports or the like on which the other elements are secured. 
     The  FIGS. 2 and 3  illustrate the locking lever  29  and the support  33  on the bow  26 . As shown in these Figures, a holder  38  is arranged in the front area of the bow  26  that is remote from the pivot bearing  27 . On the holder  38  a transverse bracket  39  is secured on which the support  33  is mounted. This is also shown in  FIG. 5 . The transverse bracket  39  extends transversely, in particular perpendicularly to the traveling direction  61 . Behind the support  33  provided on the holder  38 , when viewed In the traveling direction  61 , the locking lever  29  is pivotably supported on the pivot bearing  37  about pivot axis  70 . The pivot axis  70  is positioned transversely, in particular perpendicularly, to the longitudinal direction of the bow  26 . On the locking lever  29  a receptacle  41  is provided in which the grip pipe  22  will come to rest in the locked position of the locking lever  29 . The receptacle  41  engages the grip pipe  22  by more than 180 degrees. In this way, the receptacle  41  snaps into place on the grip pipe  22 . The receptacle  41  opens in the forward direction relative to the traveling direction  61 . The receptacle  41  has a liner  42  that protects the grip pipe  22  from becoming damaged. The liner  42  does not extend across the entire circumference of the receptacle but only across several sections. For actuating the locking lever  29 , an actuating section  36  is provided on the locking lever  29  and projects in the traveling direction  61  to the rear. In the locked position the actuating section  36  rests on the bow  26  and projects laterally past the bow  26 . In this way, the locking lever  29  can be released in a simple way. 
     As shown in  FIG. 2 , the cut-off machine  17  has an upwardly projecting locking device in the form of a locking lever  35  at the upper handle  19 . The locking lever  35  prevents accidental actuation of the throttle lever  20 . When the locking lever  35  is not pressed down, the throttle lever  20  is blocked. On the bow  26  a locking lever actuator  34  is arranged that pushes the locking lever  35  downwardly in the pivoted engaged state of the bow  26  and in this way releases the locking action. The cut-off machine  17  has a further operating element  40  that, for example, is provided for actuating a decompression valve or a purger. The bow  26  is guided in such a way across the housing  18  of the cut-off machine  17  that the operating element  40  is easily accessible for the operator. 
     In  FIG. 4 , the cut-off machine  17  is illustrated in detail on the guide cart  1 . In the housing  18  of the cut-off machine  17  a drive motor  56  is arranged which is embodied as an internal combustion engine, in particular as a two-stroke engine. The drive motor  56  however can also be a four-stroke engine. The drive motor can also be an electric motor. For starting the drive motor  56  a starter device is provided whose starter handle  57  projects outwardly from the housing  18 . On the housing  18  an extension arm  44  is secured having at one end the starter device. On the other end that faces forwardly in the traveling direction  61 , the cut-off wheel  30  is supported. In the illustrated embodiment, the cut-off wheel  30  is secured on the inner side of the extension arm  44 . It is possible to arrange the cut-off wheel  30  on the outer side of the extension arm  44 . For this purpose, the extension arm must be remounted. 
     In  FIG. 4 , an arrow  45  illustrates the cutting forces acting in operation on the cut-off wheel  30 . These cutting forces are at least partially compensated by support  33  through the protective cover  31 . The cutting forces are introduced in this connection via the bearing of the cut-off wheel  30  into the protective cover  31 . 
     The basic frame  9  of the cut-off machine  1  comprises a bearing plate  46  on which a beam  47  is arranged. The beam  47  is in particular configured as a U-shaped frame that is open toward the bearing plate  46 . On the bearing plate  46  the base plate  25  is secured. As shown in  FIG. 5 , the base plate  25  has leading and trailing ends that are upwardly bent. In the leading area, two holding pins  49  are secured that project to the rear opposite to the traveling direction  61  and parallel to the central area of the baseplate  25 . On the rearward area of the base plate  25  two lateral guides  52  are secured. The base plate  25  with its two holding pins  49  and the lateral guides  52  forms a holder  24  into which the cut-off machine  17  can be inserted. For this purpose, the cut-off machine  17  is placed with an area of the housing  18  that is adjacent to the lower section  65  of the grip pipe  22  onto the holding pins  49 . The lateral guides  52  are then positioned laterally relative to air filter cover  23  of the cut-off machine  17 . The cut-off machine  17  has a leg  60  that is supported on the base plate  25 . 
     For securing the cut-off machine  17  in the holder  24 , the bow  26  is pivoted into the fixation position  63  illustrated in  FIGS. 4 and 5 . Adjacent to the pivot bearing  27  two abutments  50  are arranged on the bow  26  as a fixation element and supported by means of a holding plate  51  on the bow  26 . The two abutments  50  rest against the side of the cut-off machine  17  which side is opposite the holding pins  49  and located rearwardly in the traveling direction  61  in the area of an air filter cover  23  of the cut-off machine  17 . The abutments  50  force the cut-off machine  17  onto the holding pins  49  so that the cut-off machine  17  is prevented from slipping off the holding pins  49 . In this way, the abutments  50  provide fixation means for the cut-off machine  17 . The abutments  50  can be made from elastic material, for example, rubber or foam material. 
     In  FIGS. 4 and 5 , the throttle lever actuator  21  is also illustrated. The throttle lever actuator  21  is embodied as a pin that is pivotably supported about axis  53 . As shown in  FIG. 4 , the pivot axis  53  extends parallel to the traveling direction  61 , i.e., parallel to the plane of the cut-off wheel  30 . For the actuating action, a Bowden cable  58  is provided that is connected to the actuating grip  16  shown in  FIG. 1 . Actuation of the actuating grip  16  effects pivoting of the throttle lever actuator  21  underneath the throttle lever  20  and upon further actuation pressure is applied onto the throttle lever  20 . The throttle lever actuator  21  is supported on holder  71 . The holder  71  is fixedly connected to the bow  26 . On the holder  71  the locking lever actuator  34  is also provided. 
     As shown in  FIG. 5 , the base plate  25  and the bow  26  form a C-shaped frame. This C-shaped frame encloses a receiving space  59  in which the housing  18  of the cut-off machine  17  is arranged. The cut-off machine  17  is secured adjacent to the lower section  65  of the grip pipe  22  by means of the holding pins  49 . On the opposite upper section  66  of the grip pipe  22 , the grip pipe  22  is arranged in the receptacle  41  of the locking lever  29 . The grip pipe  22 , the base plate  25  and the bow  26  define a closed frame that surrounds the housing  18  of the cut-off machine  17 . Cutting forces that are indicated by the arrow  45  in  FIG. 4  are introduced by the support  33  into the closed frame. The bow  26  extends across the housing  18  on a top side  67  of the cut-off machine  17  that faces upwardly in the normal working position. 
     As shown in  FIG. 5 , the support  33  is secured on a transverse bracket  39  that extends transversely, in the shown embodiment perpendicularly, to the traveling direction  61 . The support  33  is secured in a first position  43  on the transverse bracket  39 . The support  33  however can also be secured in a second position  43 ′, illustrated in dashed lines in  FIG. 5 , on the transverse bracket  39 . 
     The transverse bracket  39  is shown in  FIG. 8  schematically in a plan view. The transverse bracket  39  has a first bore  68  for fixation of the support  33  in the position  43  and a second bore  69  for fixation of the support  33  in the second position  43 ′. The support  33  is arranged in the first position  43  when the cut-off wheel  30  is arranged in the inner position as in the illustrated embodiment. When the cut-off wheel  30  is secured on the outer side of the extension arm  44  the support  33  is moved into the second position  43 ′. In the second position  43 ′ the support  33  can support the protective cover  31  when the cut-off wheel  30  is arranged on the outer side of the extension arm  44 . This is illustrated in  FIG. 6 . In this illustration the cut-off machine  17  is shown schematically on the guide cart  1  in a view from above. The protective cover  31  is illustrated with solid lines in the first position  43 . The second position shows the protective cover  31 ′ in the second position  43 ′ in dashed lines. In this position the protective cover  31 ′ and the cut-off wheel  30 , not shown in  FIG. 6 , are arranged on the outer side of the extension arm  44 . 
     As shown in  FIG. 6  the housing  18  of the cut-off machine  17  in plan view has a longitudinal center axis  54  that extends parallel to the plane of the cut-off wheel  30  in the longitudinal direction of the housing  18 . The longitudinal center axis  54  of the housing  18  coincides in the plan view with the longitudinal center axis  54  of the upper handle  19  that is arranged centrally on the housing  18 . The bow  26  is arranged in plan view adjacent to the upper handle  19 . The longitudinal center axis  55  viewed in a plan view has a spacing a to the longitudinal center axis  54 . In  FIG. 6  the pivot axis  53  of the throttle lever actuator  21  is illustrated also. The pivot axis  53  is arranged at a lateral spacing b to the longitudinal center axis  54 . The spacing b can match the spacing a; different spacings can also be provided. By arranging the pivot axis  53  adjacent to the upper handle  19  the throttle lever actuator  21  can pivot laterally underneath the upper handle  19 . The throttle lever actuator  21  does not impair the pivoting action of the bow  26 . 
     In  FIG. 6  the U-shaped configuration of the beam  47  of the base frame  9  is also shown. 
     The grip pipe  22  is part of a grip frame  72  that is vibration-decoupled relative to the drive motor  56 . This is illustrated schematically in  FIG. 7 . The grip frame  72  is connected by vibration damping elements  64  to the housing  18  of the cut-off machine  17 . The vibration damping elements  64  are arranged between the grip pipe  22  and an upper area of the housing  18 . Further vibration damping elements  64  are arranged in a lower area of the grip frame  72  between the grip frame  72  and the housing  18 . The vibration damping elements  64  are advantageously of a soft design so that a soft connection of the grip frame  72  to the housing  18  and the cut-off wheel  30  supported by means of the extension arm  44  on the housing  18  is provided. The vibration damping elements  64  and their arrangement are only schematically illustrated in  FIG. 7 . A different number of vibration damping elements  64  or a different arrangement of the vibration damping elements  64  can be advantageous. 
     In the fixation position  63  with locking lever  29  being locked, the grip pipe  22  is fixedly secured on the bow  26  and secured relative to the holding pins  49 . The cut-off wheel  30  is connected fixedly to the housing  18  by means of the extension arm  44 . However, the housing  18  is connected to the grip frame  72  by vibration damping elements  64  so that the cut-off wheel  30  relative to the grip frame  72  is movable transversely to the plane of the cut-off wheel  30 . In order to limit this movability or to inhibit it, the support  33  is provided that couples the cut-off wheel  30  directly with the bow  26  and in this way reduces the relative movement of the cut-off wheel  30  relative to the guide cart  1 . The limitation of the movability is in particular advantageous when the grip frame  72  and the housing  18  are connected to one another by soft vibration damping elements  64 . In the case of soft vibration damping elements  64  the vibrations occurring in operation can be compensated well. However, as a result of the soft design of the vibration damping elements  64  there is also a great relative movability of the cut-off wheel  30  relative to the grip frame  72 . This is not advantageous in case of an arrangement of the cut-off machine on a guide cart. This great relative movability can be limited or prevented by means of the support  33 . In particular for soft vibration damping elements  64  a support  33  is thus advantageous. The support  33  however can also be advantageous for power tools with rigidly designed vibration damping elements  64 . 
     Instead of the upper handle  19  a rear handle can be provided that extends in a direction of the longitudinal axis of the power tool on a side of the housing  18  remote from the cut-off wheel  30 . In this case, it is advantageous when the bow  26  extends also across the rear handle. The abutments  50  can be arranged between the locking lever  29  and the bearing plate  28  and thus at a spacing relative to the pivot axis  48  of the bow  26 . 
     The specification incorporates by reference the entire disclosure of German priority document 10 2007 013705.4 having a filing date of Mar. 22, 2007. 
     While specific embodiments of the invention have been shown and described in detail to illustrate the inventive principles, it will be understood that the invention may be embodied otherwise without departing from such principles.