PATENT DOCUMENT

Abstract:
The invention is based on a tool receiver for a grinder, in particular for a handheld angle grinder ( 10 ), having a carrier device ( 12, 14, 16, 182, 184, 300 ), via which an application tool ( 18, 32, 186, 188 ) can be actively connected to a drive shaft ( 54 ). 
     It is proposed that the application tool ( 18, 32, 186, 188 ) be actively connectable to the carrier device ( 14, 16, 182, 184 ) via at least one detent element ( 24, 26, 190, 192, 194, 196, 198, 200, 302 ) movable against a spring force that snaps into place in an operating position of the application tool ( 18, 32, 186, 188 ) and immobilizes the application tool ( 18, 32, 186, 188 ) with positive engagement.

Full Description:
BACKGROUND OF THE INVENTION 
   The invention is based on a tool for a grinder. 
   A tool receiver for a grinder for a handheld angle grinder is made known in EP 0 904 896 A2. The angle grinder comprises a drive shaft that carries a thread on the tool side. 
   The tool receiver for a grinder comprises a carrier and a tensioning nut. To install a sanding disk, the carrier with an installation opening is pushed onto a collar of the drive shaft and tightened with positive engagement against a bearing surface via the tensioning nut. The carrier has a collar extending in the axial direction on the tool side that comprises radially-situated recesses on two opposite sides on its outer circumference that extend in the axial direction to a base of the collar. Starting at the recesses, one groove each extends around the outer circumference of the collar against the driving direction of the drive shaft. The grooves are closed against the driving direction of the drive shaft and taper axially starting at the recesses against the driving direction of the drive shaft. 
   The sanding disk comprises a hub having an installation opening in which two tongues point radially inward on opposite sides. The tongues can be inserted in the recesses in the axial direction and then in the grooves in the circumferential direction, against the driving direction. The sanding disk is immobilized in the grooves in the axial direction via the tongues with positive engagement and in the tapering contour of the grooves via non-positive engagement. During operation, the adhesion increases as a result of reaction forces acting on the sanding disk, which counteract the driving direction. 
   In order to prevent the sanding disk from spinning off of the carrier when the brake is applied to the drive shaft, a stopper is located in the vicinity of a recess on the circumference of the collar that is supported in an opening in a fashion that allows it to move in the axial direction. In a working position with the sanding disk pointing downward, the stopper is displaced axially in the direction of the sanding disk by means of the force of gravity, closes the groove in the direction of the recess, and blocks movement of the tongue located in the groove in the driving direction of the drive shaft. 
   SUMMARY OF THE INVENTION 
   The invention is based on a tool receiver for a grinder, in particular for a handheld angle grinder, having a carrier device via which an application tool can be actively connected to a drive shaft. 
   It is proposed that the application tool be actively connectable to the carrier device via at least one detent element movable against a spring force, which detent element snaps into an operating position of the application tool and immobilizes the application tool with positive engagement. Due to the positive engagement, a high degree of reliability can be achieved, and a simple and cost-effective, tool-free, rapid mounting system can be achieved. The application tool can be reliably prevented from spinning off, even when the brake is applied to the drive shaft, which can result in high brake torques. 
   The detent element can immobilize the application tool with positive engagement directly or indirectly via an additional component, for example, via a locking lever or plunger, etc. that is supported in a fashion that allows it to rotate and/or be displaced axially and is coupled to the detent element. The detent element can immobilize the application tool directly and/or indirectly with positive engagement in various directions, such as in the radial direction, in the axial direction, and/or, particularly advantageously, in the circumferential direction. It is also possible that, due to the positive fixation of the application tool with the detent element in a first direction, e.g, in the radial direction, the application tool is immobilized in a second direction with positive engagement by means of a component separated from the detent element. 
   The movable detent element can be designed in various forms appearing practical to one skilled in the art, e.g., as an opening, projection, peg, bolt, etc., and it can be located on the application tool or on the carrier device. 
   Moreover, an advantageous encoding can be achieved by means of the positive engagement, so that only specified application tools can be secured in the tool receiver for a grinder. The carrier device can be designed at least partially as a removable adapter part, or it can be connected with the drive shaft in non-detachable fashion due to a non-positive, positive, and/or bonded connection. 
   Various application tools appearing practical to one skilled in the art can be secured with the tool receiver for a grinder, such as application tools for separating, grinding, roughing, brushing, etc. A tool receiver according to the invention can also be used to secure a grinding plate of an eccentric grinding machine. 
   The spring force can be designed to act in various directions, such as in the circumferential direction or, particularly advantageously, in the axial direction, whereby a solution can be achieved that is simple in design. The spring force can further be used to immobilize the application tool in the circumferential direction as well as in the axial direction. 
   In a further embodiment of the invention it is proposed that a drive torque be transferrable via a positive connection between the application tool and the carrier device. A high drive torque can be transferred reliably, and a drive torque can be prevented from acting on a frictional connection. 
   As an advantage, the application tool can be connected to the carrier device via a carrier element located on the application tool and/or the carrier device and extending in the axial direction, that can be guided through at least one area of a slot of the corresponding counter-element, displaced along the slot, and immobilized in an end position by the detent element. Using the carrier element extending in the axial direction, a securing in the circumferential direction and the axial direction can be achieved, wherein the application tool is advantageously immobilized with positive engagement in the axial direction via a transfer surface of the carrier element. A high degree of reliability can be achieved and additional components, weight, mounting effort, and costs can be achieved. 
   In one embodiment it is proposed that the detent element be formed by an elastically deformable component, wherein additional spring elements are spared, and simple, cost-effective designs can be achieved. 
   Advantageously, at least one detent element producing the spring force is designed as an integral part of the tool hub of the application tool. The tool hub is usually produced out of a relatively thin material that can be designed with a simple construction that is elastically deformable. It is also feasible, however, that at least one spring element is designed as an integral part of a component of the carrier device, or it is formed by an additional component, wherein the tool hub can be designed independent of a spring function. 
   In order to make a large spring deflection of the tool hub possible, at least one recess is advantageously provided in a component of the carrier device forming a bearing surface for the application tool, into which a part of the tool hub is elastically pressed in an operating position of the application tool. 
   In a further embodiment of the invention it is proposed that the slot be provided in the tool hub of the application tool, and that at least one detent element be formed by a part of the tool hub in the vicinity of the slot; in fact, particularly advantageously, the slot comprises a wide area and at least one narrow area forming the detent element in front of an end position of the carrier element. Simple, cost-effective and, in particular, essentially flat tool hubs can be achieved that can be handled easily and in space-saving fashion during manufacture and subsequent storage without the tool hubs interlocking on top of each other or with other objects. In addition to a narrowed area, however, an axial raised part in the tool hub forming the detent element would also be feasible in principle. 
   It is further proposed that at least one detent element is supported in a fashion that allows it to move against a spring element. A large displacement of the detent element during mounting of the application tool can be achieved by means of the detent element supported in movable fashion, by way of which a large overlap between two corresponding detent elements and a particularly reliable positive connection can be achieved on the one hand and, on the other, a very audible snap-in noise can be achieved that signals to the user in advantageous fashion that the snap-in procedure was completed as desired. 
   The detent element can be designed to be movable in various directions against a spring element, such as in the circumferential direction or, particularly advantageously, in the axial direction, by way of which a simple design can be achieved. 
   The detent element can even be supported in movable fashion in a component in a bearing, e.g., in a flange of the carrier device or in a tool hub of the application tool. Advantageously, the detent element can also be firmly connected to a component supported in movable fashion in a bearing in non-positive, positive, and/or bonded fashion, or it can be designed integrally connected with this, e.g., with a component supported on the drive shaft or a tool hub of the application tool. 
   If the detent element can be released from its locked position using a release button and, in particular, if it is movable against the spring element, the snap-in connection can be reliably prevented from coming loose, e.g., by means of brake torque, and safety can be increased. Operation of the application tool in two circumferential directions can be made possible in principle, and comfort during installation and removal of the application tool can be increased. 
   If the application tool is connected to the carrier device in the circumferential direction via at least a first element and, in the axial direction via at least a second element, simple and cost-effective tool hubs can be achieved that can advantageously be designed flat in shape. An interlocking of the tool hubs during manufacture and storage can be prevented, and good handling of the application tool with its tool hubs can be achieved. Moreover, the components can be advantageously designed for their function, i.e., either for immobilization in the circumferential direction or immobilization in the axial direction. The elements can be formed by a component or, advantageously, by separate components. The tool hubs can be designed simply and advantageously with a closed centering hole, and a low-vibration movement of the application tool can be achieved. Moreover, by selecting a suitable diameter for the centering hole, it can be ensured that application tools provided for the tool receiver for a grinder according to the invention can be secured to traditional grinders via heretofore known fastening devices, and, in fact, via fastening devices in particular with which the application tool can be immobilized on the drive shaft with a tensioning nut and a tensioning flange against a bearing surface in the axial direction with positive engagement and, in the circumferential direction, via non-positive connection. 
   Moreover, at least one detent element extending in the axial direction can advantageously be snapped into place in a recess of a tool hub of the application tool corresponding to the detent element in an operating position of the application tool in the axial direction, and the application tool can be immobilized with positive engagement in the circumferential direction. Using a means of attaining the object of the invention having a simple design, an advantageous positive connection can be achieved in a circumferential direction and, preferably, in both circumferential directions. The detent element extending in the axial direction can be formed by a separate bolt or an integrally-moulded peg that is produced by means of a deep-drawing procedure, etc. 
   If at least one detent element is integrally-moulded to a discoid component and/or if at least two elements for immobilizing the application tool in the axial direction are integrally-moulded to a discoid component, additional components, mounting effort, and costs can be spared. Moreover, compression connections between individual components and weak points resulting therefrom can be avoided. 

   
     BRIEF DESCRIPTION OF THE DRAWINGS 
     Further advantages result from the following drawing description. Exemplary embodiments of the invention are presented in the drawing. The drawing, the description, and the claims contain numerous features in combination. One skilled in the art will also advantageously consider the features individually and combine them into further practical combinations. 
       FIG. 1  is an angle grinder shown from above, 
       FIG. 2  is a driving flange shown from below, 
       FIG. 3  is the driving flange in  FIG. 2  shown in a side view, 
       FIG. 4  is a tool hub of a cutoff wheel shown from below, 
       FIG. 5  is an enlarged view along the line V—V in  FIG. 4 , 
       FIG. 6  is a variant of  FIG. 3 , 
       FIG. 7  is a variant of  FIG. 4 , 
       FIG. 8  is a sectional view along the line VIII—VIII in FIG.  1  through an alternative carrier device, 
       FIG. 9  is a tool hub shown from below, 
       FIG. 10  is a variant of  FIG. 8 , 
       FIG. 11  is an exploded diagram of a variant of  FIG. 8 , 
       FIG. 12  is a tool hub from  FIG. 11  shown from above, 
       FIG. 13  is a sectional view along the line XIII—XIII in  FIG. 12 , 
       FIG. 14  is a release button from  FIG. 11  shown from below, 
       FIG. 15  is a sectional view along the line XV—XV in  FIG. 14 , 
       FIG. 16  is a carrier element from  FIG. 11  shown from below, 
       FIG. 17  is a carrier element from  FIG. 16  shown from the side, 
       FIG. 18  is a sectional view along the line XVIII—XVIII in  FIG. 16 , 
       FIG. 19  is an exploded diagram of a variant of  FIG. 10 , 
       FIG. 20  is a sectional view through a carrier disk in  FIG. 19  with integrally-moulded bolts, 
       FIG. 21  is a side view of a sheet-metal plate in  FIG. 19 , and 
       FIG. 22  is a driving flange in  FIG. 19  shown from below. 
   

   DESCRIPTION OF THE PREFERRED EMBODIMENTS 
     FIG. 1  shows an angle grinder  10  from above having an electric motor—not shown in greater detail—located in a housing  96 . The angle grinder  10  can be guided via a first handle  98  extending in the longitudinal direction and integrated in the housing  96  opposite to a cutoff wheel  18  and via a second handle  102  extending at an angle to the longitudinal direction secured to a drive housing  100  in the vicinity of the cutoff wheel  186 . 
   Using the electric motor, a drive shaft  54  can be driven via a gear mechanism, not shown in greater detail, on its end pointing toward the cutoff wheel  186  of which a carrier device  182  is located (FIGS.  2  and  3 ). 
   The carrier device  182  comprises a driving flange  256 . The driving flange  256  is screwed into place on the drive shaft  54  via a thread  258  and, with a face  260  pointing in the direction  44  opposite to the cutoff wheel  186 , extends to a collar  262  on the drive shaft  54 . It would also be possible to connect a driving flange with a drive shaft in non-detachable fashion, or to design it integrated with a drive shaft. Three driving pins  202 ,  204 ,  206  are pressed into the driving flange  256  that extend in the axial direction  38  over an axial bearing surface  264  of the driving flange  256  for the cutoff wheel  186 , and that are evenly spaced in the circumferential direction. Heads are integrally-moulded on the driving pins  202 ,  204 ,  206  on the ends pointing toward the cutoff wheel  186 . The head has a larger diameter than the remaining part of the driving pin  202 ,  204 ,  206  and forms a support surface  278  in the direction of the driving flange  256 . A centering hole  266  for the cutoff wheel  186  extending in the axial direction  38  is integrally-moulded in the bearing surface  264 . 
   The cutoff wheel  186  comprises a sheet-metal hub  228  (FIG.  4 ). The sheet-metal hub  228  comprises a centering hole  268 , via which the cutoff wheel  186  can be centered on the centering collar  266  of the driving flange  256 . The sheet-metal hub  228  is connected and pressed to a grinding means  114  via a riveted joint, which is not shown in greater detail. The sheet-metal hub  228  comprises three slots  214 ,  216 ,  218  evenly spaced in the circumferential direction  34 ,  36 , each of which comprises a wide area  244 ,  246 ,  248  produced by means of a bore hole, and a narrow area  270 ,  272 ,  274  extending in the circumferential direction  36 . 
   A part of the sheet-metal hub  228  is designed as a spring shackle on one end of the slot  214 ,  216 ,  218  opposite to the wide area  244 ,  246 ,  248 , which spring shackle forms a detent element  190 ,  192 ,  194 . Instead of spring shackles integrally-moulded to the sheet-metal hub  228 , spring-mounted driving pins could also be attached to the driving flange. 
   When the cutoff wheel  186  with its sheet-metal hub  228  is placed on the driving flange  256 , the heads of the driving pins  202 ,  204 ,  206  are inserted through the wide areas  244 ,  246 ,  248  of the slots  214 ,  216 ,  218 . The sheet-metal hub  228  is oriented with its centering hole  268  over the centering flange  266 . By rotating the sheet-metal hub  228  relative to the driving flange  256  against the driving direction  34 , the spring shackles or the detent elements  190 ,  192 ,  194  move under the heads of the driving pins  202 ,  204 ,  206 . The direction of rotation  36  for securing the cutoff wheel  186  is opposite to the driving direction  34  of the drive shaft  54 . This ensures that the cutoff wheel  186  does not unintentionally come loose during operation. The heads of the driving pins  202 ,  204 ,  206  glide over the lugs  276  of the spring shackles or the detent elements  190 ,  192 ,  194  when rotated, and displace them in the axial direction  44  toward the driving flange  256 . When the heads have passed the lugs  276  or an operating position of the cutoff wheel  186  has been reached, the spring shackles spring back partially in the axial direction  38  and grip behind the heads with positive engagement. A snap-in noise produced thereby can serve to ensure the operator that the sheet-metal hub  228  is locked in place as desired. A remaining tension or spring force of the spring shackles presses the cutoff wheel  186  against the bearing surface  264  without play in the axial direction  44 . 
   The drive torque of the electric motor is transferred from the driving flange  256  with positive engagement via the driving pins  202 ,  204 ,  206  and via the spring shackles or via the detent elements  190 ,  192 ,  194  to the sheet-metal hub  228 . A brake torque that is produced and opposes the drive torque is transferred with positive engagement from the heads of the driving pins  202 ,  204 ,  206  via the lugs  276  of the detent elements  190 ,  192 ,  194  to the sheet-metal hub  228 , and with frictional engagement from the bearing surface  264  to a corresponding bearing surface of the sheet-metal hub  228 . The magnitude of the friction force thereby depends on the surface condition of the two bearing surfaces  264  and a clamping force of the spring shackles, and can be adjusted accordingly via these parameters. The cutoff wheel  186  is reliably prevented from spinning off. So as to transfer particular high brake torques, a Velcro connection or another type of positive-engagement connection can be created between the bearing surfaces, for example. 
   To remove the cutoff wheel  186 , the cutoff wheel  186  is rotated in the driving direction  34  relative to the driving flange  256  so that the heads of the driving pins  202 ,  204 ,  206  glide over the lugs  276  of the detent elements  190 ,  192 ,  194 . When the driving pins  202 ,  204 ,  206  come to rest in the wide areas  244 ,  246 ,  248  of the slots  214 ,  216 ,  218 , the cutoff wheel  186  can be removed from the driving flange  256  in the axial direction  38 . 
   An alternative carrier device  184  having a corresponding cutoff wheel  188  is shown in  FIGS. 6 and 7 . Components that essentially remain the same are basically labelled with the same reference numerals in the exemplary embodiments shown. Moreover, the description of the exemplary embodiment in  FIGS. 1 through 5  can be referred to for the exemplary embodiment in  FIGS. 6 and 7 . 
   The carrier device  184  comprises a driving flange  234 . Three driving pins  208 ,  210 ,  212  are pressed into the driving flange  234 , which extend in the axial direction  38  over an axial bearing surface  232  of the driving flange  234  for the cutoff wheel  188 , and are spaced evenly in the circumferential direction  34 ,  36 . Heads are integrally-moulded with the driving pins  208 ,  210 ,  212  on their ends pointing toward the cutoff wheel  188 . The head has a larger diameter than the remaining part of the driving pin  208 ,  210 ,  212  and forms a conical, tapering transfer surface  226  in the axial direction  44  toward the driving flange  234 . Recesses  236  are provided in the bearing surface  232  in the vicinity of the driving pins  208 ,  210 ,  212 . 
   The cutoff wheel  188  comprises a sheet-metal hub  230  (FIG.  7 ). The sheet-metal hub  230  comprises a centering hole  268 , via which the cutoff wheel  188  can be centered on a centering collar  266  of the driving flange  234 . The sheet-metal hub  230  is connected and pressed to a grinding means  144  via a riveted joint, which is not shown in greater detail. The sheet-metal hub  230  contains three slots  220 ,  222 ,  224  evenly spaced in the circumferential direction  34 ,  36 , each of which comprises a wide area  238 ,  240 ,  242  produced by means of a bore hole, and a narrow area, each of which forms a detent element  196 ,  198 ,  200 , in front of an end position  250 ,  252 ,  254  of the driving pins  208 ,  210 ,  212 . 
   When the cutoff wheel  188  with its sheet-metal hub  230  is placed on the driving flange  234 , the heads of the driving pins  208 ,  210 ,  212  are inserted through the wide areas  238 ,  240 ,  242  of the slots  220 ,  222 ,  224 . The sheet-metal hub  230  is oriented with its centering hole  268  over the centering collar  266 . When the sheet-metal hub  230  is rotated against the driving direction  24  relative to the driving flange  234 , the driving pins  208 ,  210 ,  212  move in the curved slots  220 ,  222 ,  224 . The direction of rotation  36  for securing the cutoff wheel  188  is opposite to the driving direction  34  of the drive shaft  54 . This ensures that the cutoff wheel  188  does not unintentionally come loose during operation. 
   When the sheet-metal hub  230  is rotated, the heads of the driving pins  208 ,  210 ,  212  glide with their conical transfer surfaces  226  over the narrowed areas or over the detent elements  196 ,  198 ,  200  of the slots  220 ,  222 ,  225 , each of them thereby pressing part of the sheet-metal hub  230  axially in the recesses  236  of the bearing surface  232  of the driving flange  234  provided for this in the vicinity of the slots  220 ,  222 ,  224  in the direction  44  of the driving flange  234 . When the cutoff wheel  188  has reached an operating position, or when the driving pins  208 ,  210 ,  212  have reached their end position  250 ,  252 ,  254  having a width slightly larger than the middle area of the slots  220 ,  222 ,  224 , the detent elements  196 ,  198 ,  200  snap into place behind the heads of the driving pins  208 ,  210 ,  212  with positive engagement. In the end positions  250 ,  252 ,  254 , the sheet-metal hub  230  is displaced elastically by a defined amount by the conical transfer surfaces  226  of the driving pins  208 ,  210 ,  212 . A remaining elastic clamping force of the sheet-metal hub  230  presses this against the bearing surface  232 . The sheet-metal hub  230  is secured without play in the axial direction  38 ,  44  with positive engagement. 
   The drive torque of the electric motor is transferred from the driving flange  234  with positive engagement via the driving pins  208 ,  210 ,  212  at the end of the slots  220 ,  222 ,  224  to the sheet-metal hub  230 . A brake torque that is produced and opposes the drive torque is transferred with positive engagement from the heads of the driving pins  208 ,  210 ,  212  via the detent elements  196 ,  198 ,  200  to the sheet-metal hub  230 , and with frictional engagement from the bearing surface  232  to a corresponding bearing surface of the sheet-metal hub  230 . The magnitude of the friction force thereby depends on the surface condition of the two bearing surfaces  232  and a clamping force of the detent elements  196 ,  198 ,  200 , and can be adjusted accordingly via these parameters. The cutoff wheel  186  is reliably prevented from spinning off. 
   To remove the cutoff wheel  188 , the cutoff wheel  188  is rotated in the driving direction  34  relative to the driving flange  234  so that the heads of the driving pins  208 ,  210 ,  212  glide over the detent elements  196 ,  198 ,  200 . When the driving pins  208 ,  210 ,  212  come to rest in the wide areas  238 ,  240 ,  242  of the slots  220 ,  222 ,  224 , the cutoff wheel  188  can be removed from the driving flange  234  in the axial direction  38 . 
     FIG. 8  shows a sectional view along the line VIII—VIII in  FIG. 1 through a  carrier device  12  that is an alternative to FIG.  2 . The carrier device  12  comprises a driving flange  82  pressed solidly to a side of a drive shaft  54  facing a cutoff wheel  18  and a driving disk  56  supported on the drive shaft  54  in such a fashion that it can be displaced axially against a coil spring  20  located in the center. 
   Three pins  40  are pressed into the driving flange  82  that extend in the axial direction  38  toward the cutoff wheel  18  over the driving flange  82  and that are evenly spaced in the circumferential direction  34 ,  36 . Each of the pins comprises a head on its end pointing toward the cutoff wheel  18  that has a larger diameter compared to a remaining part of the pin  40 , and, on a side facing the driving flange  82 , a conical support surface  76  tapering in the axial direction  44 . The driving flange  82  forms an axial bearing surface  80  for the cutoff wheel  18  that establishes an axial position of the cutoff wheel  18  and in which recesses  84  are provided in the vicinity of the pins  40 . Moreover, three axial through holes  104  are provided in the driving flange  82  that are evenly spaced in the circumferential directin  34 ,  36 ; in fact, one through hole  104  each is located between two pins  40  in the circumferential direction. 
   Three bolts  24  are pressed in the driving disk  56  supported on the drive shaft  54  in axially displaceable fashion, which extend in the axial direction  38  toward the cutoff wheel  18  over the driving disk  56  and are evenly spaced in the circumferential direction  34 ,  36 . The driving disk  56  is pressed against the driving flange  82  by the coil spring  20  in the direction  38  toward the cutoff wheel  18 . The bolts  24  extend through the through holes  104  and extend in the axial direction  38  over the driving flange  82 . 
   Moreover, the carrier device  12  comprises a release button  28  designed in the shape of a pot, located in the middle, on the side facing the cutoff wheel  18 . The release button  28  comprises three segments  106  evenly spaced in the circumferential direction  34 ,  36  and extending in the axial direction  44  toward the axially movable driving disk  56  that grip through corresponding recesses  108  of the driving flange  82  and are connected to the driving disk  56  in the axial direction  38  via a circlip  110  secure the release button  28  from falling out. The release button  28  is inserted in displaceable fashion into a ring-shaped recess  112  in the driving flange  82  in the axial direction  38 ,  44 . 
   The cutoff wheel  18  comprises a sheet-metal hub  52  that is solidly connected and pressed to a grinding means  114  via a riveted joint which is not shown in greater detail (FIG.  9 ). The tool hub could also be produced out of another material appearing practical to one skilled in the art, such as plastic, etc. The sheet-metal hub  52  comprises three sequential holes  46 ,  48 ,  50  in the circumferential direction  34 ,  36 , the diameter of which is slightly greater than the diameter of the bolts  24 . Moreover, the sheet-metal hub  52  comprises three slots  64 ,  66 ,  68  located in sequence in the circumferential direction  34 ,  36  and extending in the circumferential direction  34 ,  36 , each of which comprises a narrow area  70 ,  72 ,  74  and a wide area  58 ,  60 ,  62  produced by means of a bore hole, the diameter of which is slightly larger than the diameter of the heads of the pins  40 . 
   The sheet-metal hub  52  comprises a centering hole  116 , the diameter of which is advantageously selected so that the cutoff wheel  18  can also be mounted on a traditional angle grinder using a traditional mounting system with a mounting flange. A “downward compatibility” is ensured. 
   When mounting the cutoff wheel  18 , the cutoff wheel  18  is slid with its centering hole  116  onto the release button  28  and centered radially. The cutoff wheel  18  is then rotated until the pins  40  grip in the wide areas  58 ,  60 ,  62  of the slots  64 ,  66 ,  68  of the sheet-metal hub  52  provided for this. By pressing the sheet-metal hub  52  against the bearing surface  80  of the driving flange  82 , the bolts  24  in the through holes  104  and the driving disk  56  are displaced against a spring force of the coil spring  20  on the drive shaft  54  axially in the direction  44  opposite to the cutoff wheel  18 . 
   Rotating the sheet-metal hub  52  further against the driving direction  34  displaces the pins  40  in the curved narrow areas  70 ,  72 ,  74  of the slots  64 ,  66 ,  68 . The pins  40  thereby press with their conical support surfaces  76  on the edges of the slots  64 ,  66 ,  68 , and press them elastically into the recesses  84  of the driving flange  82 . The sheet-metal hub  52  is thereby pressed against the bearing surface  80  and immobilized in the axial direction  38 ,  44 . 
   In a final operating position of the cutoff wheel  18 , the holes  46 ,  48 ,  50  come to rest in the sheet-metal hub  52  via the through holes  104  of the driving flange  82 . 
   The bolts  24  are displaced axially in the direction  38  of the cutoff wheel  18  by means of the spring force of the coil spring  20 , snap into place in the holes  46 ,  48 ,  50  of the sheet-metal hub  52 , and immobilize them with positive engagement in both circumferential directions  34 ,  36 . When they snap into place, a snap-in noise audible to the operator is produced which signals to the operator that the tool is ready to use. 
   A drive torque of the electric motor of the angle grinder  10  can be transferred to the cutoff wheel  18  from the drive shaft  54  to the driving flange  82  with non-positive engagement, and from the driving flange  82  via the bolts  24  with positive engagement. The drive torque is transferred exclusively via the bolts  24 , because the slots  64 ,  66 ,  68  are designed so that the pins  40  do not come to rest at the narrow end  70 ,  72 ,  74  of the slots when the bolts  24  are snapped into place. Moreover, a brake torque occurring during and after the electric motor is switched off and that is opposed to the drive torque can be transferred with positive engagement by the driving flange  82  to the cutoff wheel  18  via the bolts  24 . The cutoff wheel  18  is reliably prevented from unintentionally coming loose. An advantageous, even distribution of forces and mass is achieved by means of the three bolts  24  evenly spaced in the circumferential direction  34 ,  36 . 
   The release button  28  is pressed to release the cutoff wheel  18  from the angle grinder  10 . The driving disk  56  is thereby displaced with the bolts  24  via the release button  28  against the coil spring  20  in the axial direction  44  opposite to the cutoff wheel  18 , whereby the bolts  24  move in the axial direction  44  out of their locked position or out of the holes  46 ,  48 ,  50  of the sheet-metal hub  52 . The cutoff wheel  18  is then rotated in the driving direction  34  until the pins  40  come to rest in the wide areas  58 ,  60 ,  62  of the slots  64 ,  66 ,  68  and the cutoff disk  18  can be removed from the driving flange  82  in the axial direction  38 . After the release button  28  is released, the driving disk  56 , the bolts  24 , and the release button  28  are pushed back to their initial positions by means of the coil spring  20 . 
   An exemplary embodiment with a carrier device  14  that is an alternative to the exemplary embodiment in  FIG. 8  is shown in FIG.  10 .  FIGS. 8 and 9  can be referred to with regard for features and functions that remain the same. 
   The carrier device  14  comprises a driving flange  90  pressed onto the drive shaft  54 . A collar  92  is integrally-moulded to a driving flange  90  forming a bearing surface  88  for the cutoff wheel  18 , via which collar  92  the cutoff wheel  18  is centered radially in its state with the centering hole  116  mounted. Radial forces can be advantageously absorbed by the driving flange  90  without stressing the release button  28 . 
   In order to immobilize the cutoff wheel  18 , moreover, three pins  42  spaced evenly in sequence in the circumferential direction  34 ,  36  and extending in the axial direction  38  over the bearing surface  88  are supported in the driving flange  90  in a fashion that allows them to be displaced in the axial direction  38  against one disk spring  86  in each case. Each of the pins  42  comprises a head on its end pointing toward the cutoff wheel  18  that has a larger diameter than a remaining portion of the pin  42  and has a conical transfer surface  78  tapering in the axial direction  44  on a side facing the driving flange  90 , and a support surface  78   a  extending in parallel to the bearing surface  88 . When the heads of the pins  42  are inserted through the wide areas  58 ,  60 ,  62  of the slots  64 ,  66 ,  68 , rotating the sheet-metal hub  52  against the driving direction  34  causes the pins  42  to be displaced into the curved narrow areas  70 ,  72 ,  74  of the slots  64 ,  66 ,  68 . The pins  42  are therefore displaced axially over the conical transfer surfaces  78  against the pressure of the disk spring  86  in direction  38  until the support surfaces  78   a  of the pins  42  overlap the edges of the slots  64 ,  66 ,  68  in the curved narrow areas  70 ,  72 ,  74 . 
   In the installed state, the disk springs  86  press the cutoff wheel  18  against the bearing surface  88  via the support surfaces  78   a  of the pins  42 . Instead of a plurality of disk springs  86 , the pins can also be loaded via a common spring element, e.g., via a disk spring extending over the entire circumference and not shown in greater detail. The exemplary embodiment shown in  FIG. 10  having the pins  42  supported in axially displaceable fashion is suited in particular for thick and/or only slightly elastically deformable tool hubs. 
     FIGS. 11 through 18  show a further exemplary embodiment having a carrier device  16 . The carrier device  16  comprises a driving flange  118  secured to a drive shaft—not shown in greater detail—via a thread  120  ( FIG. 11 ,  FIGS. 16 ,  17 , and  18 ). The driving flange could also be designed connected to the drive shaft via a non-detachable connection, or it could be designed as an integral part with this. 
   The driving flange  118  comprises three segments  122 ,  124 ,  126  and intermediate spaces  128 ,  130 ,  132  between them located in sequence in the circumferential direction  34 ,  36  and extending in the axial direction  38  to a cutoff wheel  32  (FIG.  16 ). Each of these segments  122 ,  124 ,  126  comprises a groove  134 ,  136 ,  138  on its circumference that is closed against the driving direction  34  in each case via a rotary stop  140 ,  142 ,  144  and is open in the driving direction  34 . Moreover, the driving flange  118  comprises a bearing surface  180  that establishes an axial position of the cutoff wheel  32 . Moreover, the segments  122 ,  124 ,  126  form a centering collar for the cutoff wheel  32 , via which the cutoff wheel  32  can be centered. 
   In the installed state, a detent element  26  is connected to the driving flange  118  via three snap-in pegs  146 ,  148 ,  150  spaced around the circumference, that grip through corresponding recesses  158 ,  160 ,  162  of the driving flange  118  and grip radially outward behind the driving flange  118  ( FIGS. 11 ,  14 , and  15 ). Three locking segments  152 ,  154 ,  156  located in sequence in the circumferential direction  34 ,  36  and extending radially outward are integrally-moulded to the detent element  26 , which also forms a release button  30 . A coil compression spring  22  is located between the driving flange  118  and the detent element  26 , against which the detent element  26  can be displaced relative to the driving flange  118  in the axial direction  44  opposite to the cutoff wheel  32 . The detent element  26  is thereby guided over radially outwardly-pointing bearing surfaces  164 ,  166 ,  168  between the locking segments  152 ,  154 ,  156  in radially inwardly-pointing surfaces of the segments  122 ,  124 ,  126  of the driving flange  118 . To prevent the detent element  26  from tilting and to achieve small bearing surfaces  164 ,  166 ,  168 , the bearing surfaces  164 ,  166 ,  168  are formed by projections  170  extending radially outward (FIG.  14 ). 
   In the installed state, the locking segments  152 ,  154 ,  156  are located in the intermediate spaces  128 ,  130 ,  132  of the driving flange  118  and extend radially over a groove bottom of the grooves  134 ,  136 ,  138 . In an initial position before installation of the cutoff wheel  12 , the locking segments  152 ,  154 ,  156  of the detent element  26  lie in front of the grooves  134 ,  136 ,  138 , loaded by the preloaded coil compression spring  22 , in fact. 
   The cutoff wheel  32  comprises a ring-shaped sheet-metal hub  94  that is press-moulded with a grinding means  114  on its outer diameter and comprises tongues or spring elements  172 ,  174 ,  176  pointing radially outward on its internal diameter ( FIGS. 11 ,  12 , and  13 ). The spring elements  172 ,  174 ,  176 , in combination with the driving flange  118  and the release button  30 , serve to transfer the drive torque, to axially position the cutoff wheel  32 , and to secure the cutoff wheel  32  from spinning off when the electric motor is switched on or when the brake is applied to the drive shaft. Moreover, the spring elements, in addition to the segments  122 ,  124 ,  126 , can be used to center the cutoff wheel  32  to the drive shaft. 
   When the cutoff wheel  32  is installed, it is oriented on the driving flange  118  in such a fashion that the spring elements  172 ,  174 ,  176  on the internal diameter of the sheet-metal hub  94  point into the intermediate spaces  128 ,  130 ,  132  between the segments  122 ,  124 ,  126  on the driving flange  118 . The spring elements  172 ,  174 ,  176  of the cutoff wheel  32  lie on the locking segments  152 ,  154 ,  156  of the release button  30 . The cutoff wheel  32  is then pressed in the axial direction until it reaches the bearing surface  180  of the driving flange  118 . The spring elements  172 ,  174 ,  176  displace the release button  30  with their locking segments  152 ,  154 ,  156  against the spring force of the coil compression spring  22  in the direction  44  axially opposite to the cutoff wheel  32 . The locking segments  152 ,  154 ,  156  are pressed into recesses  178  of the driving flange  118  ( FIG. 18 ) so that the spring elements  172 ,  174 ,  176  come to rest in front of the grooves  134 ,  136 ,  138 . 
   The cutoff wheel  32  is thereby centered radially via the centering collar formed by the segments  122 ,  124 ,  126 . When the cutoff wheel  32  is turned against the driving direction  34 , the spring elements  172 ,  174 ,  176  grip into the grooves  134 ,  136 ,  138  of the driving flange  118 . A spring-groove connection is established. The spring elements  172 ,  174 ,  176  comprise the length of the grooves  134 ,  136 ,  138  in the circumferential direction  36 . If the spring elements  172 ,  174 ,  176  are pushed into the grooves  134 ,  136 ,  138  completely, or if an operating position of the cutoff disk  32  is reached, the detent element  26  snaps into place with its locking segments  152 ,  154 ,  156 , wherein the coil compression spring  22  presses the detent element  26  with its locking segments  152 ,  154 ,  156  into its initial position, so that the locking segments  152 ,  154 ,  156  come to rest in front of the grooves  134 ,  136 ,  138  once more. The detent element  26 , with its locking segments  152 ,  154 ,  156 , immobilizes the cutoff wheel  32  against the driving direction  34  with positive engagement. 
   A snap-in noise that is audible to the operator is produced during the snap-in procedure that signals to the user that the snap-in procedure was completed as desired and the tool is ready to use. 
   The drive torque is transferred with positive engagement via the rotary stops  140 ,  142 ,  144  of the driving flange  118  to the spring elements  172 ,  174 ,  176  of the sheet-metal hub  94  or the cutoff wheel  32 . The cutoff wheel  32  is centered via the centering collar formed by the segments  122 ,  124 ,  126  of the driving flange  118  and is held in its axial position by means of the bearing surface  180  and the grooves  134 ,  136 ,  138 . Moreover, a brake torque occurring during and after the the electric motor is switched off that opposes the drive torque is transferred with positive engagement from the locking segments  152 ,  154 ,  156  and the driving flange  118  to the spring elements  172 ,  174 ,  176  of the cutoff wheel  32 . 
   A compensation for play is achieved in the axial direction by means of a spring element—not shown in greater detail—formed by a metal strip in the grooves  134 ,  136 ,  138 . Moreover, a compensation for play could be achieved via other spring elements appearing practical to one skilled in the art, such as via spring-loaded balls that are located in suitable locations of the driving flange and that immobilize the tool hub of the cutoff wheel without play, and/or via a slight oversizing of the spring elements of the tool hub, by means of a slightly wedge-shaped form of the grooves and the spring element of the tool hub, etc. 
   To release the cutoff wheel  32 , the release button  30  is pressed in the axial direction  44  opposite to the cutoff wheel  32 . The locking segments  152 ,  154 ,  156  of the release button  30  or the detent element  26  are pushed into the recesses  178  of the driving flange  118 . The cutoff wheel  32  can then be rotated in the driving direction  34  with its spring elements  172 ,  174 ,  176  out of the grooves  134 ,  136 ,  138  of the driving flange  118  and removed in the axial direction  38 . When the cutoff wheel  32  is removed, the release button  30  is pressed back into its initial position by the coil compression spring  22 . 
   An exemplary embodiment having a carrier device  300  that is an alternative to the exemplary embodiment in  FIG. 10  is shown in FIG.  19 . The carrier device  300  comprises a driving flange  90  that forms a bearing surface  88  for a cutoff wheel that is not shown in greater detail. A collar  92  is integrally moulded to the carrier flange  90  on the side facing the cutoff disk, via which the cutoff disk is centered radially with its centering hole in the installed state. Radial forces can be advantageously absorbed by the driving flange  90  without stressing the release button  28 . 
   A sheet-metal plate  308  having three integrally-moulded fastening elements  306  extending in the axial direction  38  and spaced evenly in the circumferential direction are located on a side of the driving flange  90  opposite to the cutoff wheel to lock the cutoff wheel in place axially. The fastening elements  306  are integrally-moulded to the sheet-metal plate  308  in a bending procedure. 
   During installation, the driving flange  90 , an undulate washer  312 , and the sheet-metal plate  308  are preassembled. The undulate washer  312  is thereby slid onto a collar  322  of the driving flange  90  pointing in the direction opposite to the cutoff wheel. The fastening elements  306  of the sheet-metal plate  308 , which comprise a hook-shaped extension on its exposed end with an angled surface  310  pointing in the circumferential direction (FIGS.  19  and  21 ), are guided in the axial direction  38  through recesses  314  in the driving flange  90 , in fact, each of them through widened areas  316  of the recesses  314  (FIGS.  19  and  21 ). By compressing and rotating the sheet-metal plate  308  and the driving flange  90  against each other, the undulate washer  312  is preloaded, and the sheet-metal plate  308  and the driving flange  90  are connected with positive engagement in the axial direction  38 ,  44 , in fact, by the hook-shaped extensions rotating in narrow areas  318  of the recesses  314  ( FIGS. 19 ,  21 , and  22 ). The sheet-metal plate  308  is then supported, loaded by the undulate washer  312 , on the bearing surface  88  of the driving flange  90  via edges  310   a  of the hook-shaped extensions that point axially in the direction opposite to the cutoff wheel. 
   After the sheet-metal plate  308  with the integrally-moulded fastening elements  306 , the undulate washer  312 , and the driving flange  90  are preassembled, a compression spring  20  and a driving disk  304  having three integrally-moulded bolts  302  extending in the axial direction  38  and spaced evenly around the circumference are slid onto a drive shaft  54 . The bolts  302  are integrally-moulded to a sheet-metal plate forming the driving disk  304  in a deep-drawing process (FIG.  20 ). 
   The preassembled assembly consisting of the sheet-metal plate  308 , the undulate washer  312  and the driving flange  90  are then mounted on the drive shaft  54 . During installation, the bolts  302  are guided through recesses  320  integrally-moulded on the circumference of the sheet-metal plate  308  and through through holes  104  in the driving flange  90  and grip through the through holes  104  in the installed state. The sheet-metal plate  308  and the driving flange  90  are secured via the bolts  302  against rotating in relation to each other. 
   The driving flange  90  is pressed onto the drive shaft  54  and then secured with a retaininer ring not shown in further detail. In addition to a compression connection, other connections appearing practical to one skilled in the art are also feasible, such as a threaded connection, etc. 
   When, during mounting of a cutoff wheel  18  (refer to FIGS.  8  and  10 ), the hook-shaped extensions of the fastening elements  306  are guided through the wide areas  58 ,  60 ,  62  of the slots  64 ,  66 ,  68  of the sheet-metal hub  52  (FIG.  19 ), rotating the sheet-metal hub  52  against the driving direction  34  causes the hook-shaped extensions to be pushed into the curved, narrow areas  70 ,  72 ,  74  of the slots  64 ,  66 ,  68  of the sheet-metal hub  52 . In doing so, the sheet-metal plate  308  with the fastening elements  306  is displaced axially via the angled surfaces  310  against the pressure of the undulate washer  312  in direction  38  until the edges  310 a of the hook-shaped extensions come to rest in curved, narrow areas  70 ,  72 ,  74  laterally next to the slots  64 ,  66 ,  68  of the sheet-metal hub  53 . In the installed state, the undulate washer  312  presses the cutoff wheel  18  against the bearing surface  88  via the edges  310   a  of the hook-shaped extensions. 
   As an alternative, the fastening elements and the slots can be designed rotated by 180° in the sheet-metal hub, so that the mounting direction reverses, and the sheet-metal hub is rotated in the driving direction during mounting. If the fastening elements are designed rotated by 180°, an angled surface of a lower front edge of the fastening element leads during operation, so that injuries by a front edge can be prevented. 
   
     
       
             
           
             
             
             
           
         
             
                 
             
             
               Reference Numerals 
             
             
                 
             
           
           
             
                 
             
           
        
         
             
                 
               10 
               Angle grinder 
             
             
                 
               12 
               Carrier device 
             
             
                 
               14 
               Carrier device 
             
             
                 
               16 
               Carrier device 
             
             
                 
               18 
               Application tool 
             
             
                 
               20 
               Spring element 
             
             
                 
               22 
               Spring element 
             
             
                 
               24 
               Detent element 
             
             
                 
               26 
               Detent element 
             
             
                 
               28 
               Release button 
             
             
                 
               30 
               Release button 
             
             
                 
               32 
               Application tool 
             
             
                 
               34 
               Circumferential direction 
             
             
                 
               36 
               Circumferential direction 
             
             
                 
               38 
               Direction 
             
             
                 
               40 
               Fastener 
             
             
                 
               42 
               Fastener 
             
             
                 
               44 
               Direction 
             
             
                 
               46 
               Recess 
             
             
                 
               48 
               Recess 
             
             
                 
               50 
               Recess 
             
             
                 
               52 
               Tool hub 
             
             
                 
               54 
               Drive shaft 
             
             
                 
               56 
               Component 
             
             
                 
               58 
               Area 
             
             
                 
               60 
               Area 
             
             
                 
               62 
               Area 
             
             
                 
               64 
               Slot 
             
             
                 
               66 
               Slot 
             
             
                 
               68 
               Slot 
             
             
                 
               70 
               Area 
             
             
                 
               72 
               Area 
             
             
                 
               74 
               Area 
             
             
                 
               76 
               Seating surface 
             
             
                 
               78 
               Transfer surface 
             
             
                 
               80 
               Bearing surface 
             
             
                 
               82 
               Component 
             
             
                 
               84 
               Recess 
             
             
                 
               86 
               Spring element 
             
             
                 
               88 
               Bearing surface 
             
             
                 
               90 
               Component 
             
             
                 
               92 
               Collar 
             
             
                 
               94 
               Tool hub 
             
             
                 
               96 
               Housing 
             
             
                 
               98 
               Handle 
             
             
                 
               100 
               Drive housing 
             
             
                 
               102 
               Handle 
             
             
                 
               104 
               Through hole 
             
             
                 
               106 
               Segment 
             
             
                 
               108 
               Recess 
             
             
                 
               110 
               Circlip 
             
             
                 
               112 
               Recess 
             
             
                 
               114 
               Grinding means 
             
             
                 
               116 
               Centering hole 
             
             
                 
               118 
               Driving flange 
             
             
                 
               120 
               Thread 
             
             
                 
               122 
               Segment 
             
             
                 
               124 
               Segment 
             
             
                 
               126 
               Segment 
             
             
                 
               128 
               Intermediate space 
             
             
                 
               130 
               Intermediate space 
             
             
                 
               132 
               Intermediate space 
             
             
                 
               134 
               Groove 
             
             
                 
               136 
               Groove 
             
             
                 
               138 
               Groove 
             
             
                 
               140 
               Rotary stop 
             
             
                 
               142 
               Rotary stop 
             
             
                 
               144 
               Rotary stop 
             
             
                 
               146 
               Snap-in peg 
             
             
                 
               148 
               Snap-in peg 
             
             
                 
               150 
               Snap-in peg 
             
             
                 
               152 
               Locking segment 
             
             
                 
               154 
               Locking segment 
             
             
                 
               156 
               Locking segment 
             
             
                 
               158 
               Recess 
             
             
                 
               160 
               Recess 
             
             
                 
               162 
               Recess 
             
             
                 
               164 
               Bearing surface 
             
             
                 
               166 
               Bearing surface 
             
             
                 
               168 
               Bearing surface 
             
             
                 
               170 
               Projection 
             
             
                 
               172 
               Spring element 
             
             
                 
               174 
               Spring element 
             
             
                 
               176 
               Spring element 
             
             
                 
               178 
               Recess 
             
             
                 
               180 
               Bearing surface 
             
             
                 
               182 
               Carrier device 
             
             
                 
               184 
               Carrier device 
             
             
                 
               186 
               Application tool 
             
             
                 
               188 
               Application tool 
             
             
                 
               190 
               Detent element 
             
             
                 
               192 
               Detent element 
             
             
                 
               194 
               Detent element 
             
             
                 
               196 
               Detent element 
             
             
                 
               198 
               Detent element 
             
             
                 
               200 
               Detent element 
             
             
                 
               202 
               Carrier element 
             
             
                 
               204 
               Carrier element 
             
             
                 
               206 
               Carrier element 
             
             
                 
               208 
               Carrier element 
             
             
                 
               210 
               Carrier element 
             
             
                 
               212 
               Carrier element 
             
             
                 
               214 
               Carrier element 
             
             
                 
               216 
               Slot 
             
             
                 
               218 
               Slot 
             
             
                 
               220 
               Slot 
             
             
                 
               222 
               Slot 
             
             
                 
               224 
               Slot 
             
             
                 
               226 
               Transfer surface 
             
             
                 
               228 
               Component 
             
             
                 
               230 
               Component 
             
             
                 
               232 
               Bearing surface 
             
             
                 
               234 
               Component 
             
             
                 
               236 
               Recess 
             
             
                 
               238 
               Area 
             
             
                 
               240 
               Area 
             
             
                 
               242 
               Area 
             
             
                 
               244 
               Area 
             
             
                 
               246 
               Area 
             
             
                 
               248 
               Area 
             
             
                 
               250 
               End position 
             
             
                 
               252 
               End position 
             
             
                 
               254 
               End position 
             
             
                 
               256 
               Driving flange 
             
             
                 
               258 
               Thread 
             
             
                 
               260 
               Face 
             
             
                 
               262 
               Collar 
             
             
                 
               264 
               Bearing surface 
             
             
                 
               266 
               Centering collar 
             
             
                 
               268 
               Centering hole 
             
             
                 
               270 
               Area 
             
             
                 
               272 
               Area 
             
             
                 
               274 
               Area 
             
             
                 
               276 
               Lug 
             
             
                 
               278 
               Seating surface 
             
             
                 
               300 
               Carrier device 
             
             
                 
               302 
               Detent element 
             
             
                 
               304 
               Component 
             
             
                 
               306 
               Element 
             
             
                 
               308 
               Component 
             
             
                 
               310 
               Angled surface 
             
             
                 
               310a 
               Edge 
             
             
                 
               312 
               Spring element 
             
             
                 
               314 
               Recess 
             
             
                 
               316 
               Area 
             
             
                 
               318 
               Area 
             
             
                 
               320 
               Recess 
             
             
                 
               322 
               Collar