Portable power tool having a covering device

Abstract

A portable power tool having a plate tool (30), in particular a sanding plate or polishing plate, and a drive motor, arranged in a machine housing, for driving the plate tool into an oscillating and/or rotating and/or eccentric movement of a machining surface of the plate tool, wherein the portable power tool is able to be guided with the machining surface in a main working direction forwards and to the side transversely to the main working direction in at least one transverse working direction in order to sand or polish a workpiece surface, wherein the portable power tool has a covering device for the plate tool, said covering device having at least one protective wall which is disposed upstream of at least one lateral surface, extending next to the machining surface, of the plate tool with regard to the main working direction and/or the transverse working direction in order to protect against contact with obstacles.

Claims

1. A portable machine tool having a pad tool and a drive motor, which is arranged in a machine housing for driving the pad tool to produce an oscillating or rotating or eccentric movement of a processing face of the pad tool, wherein the portable machine tool can be guided with the processing face forwards in a main working direction and laterally transversely relative to the main working direction in at least one transverse working direction for a grinding or polishing operation of a workpiece surface, wherein the machine housing has a front side facing forwards in the main working direction and a rear side opposite the front side, the rear side having at least one of an extraction connection for extracting particles generated by the pad tool or a handle portion to be gripped with a hand, the extraction connection or the handle portion protruding from the rear side of the machine housing in a direction opposite the main working direction, wherein the portable machine tool has, for the pad tool, a covering device, which has at least one protection wall which is arranged upstream of at least one side face of the pad tool which extends beside the processing face with respect to the main working direction or the at least one transverse working direction in order to protect against contact with obstacles, wherein the at least one protection wall of the covering device completely or substantially covers side flanks of the pad tool, and wherein the covering device is a one-piece clamp, the clamp comprising a base member and two lateral members extending rearwardly from the base member, the two lateral members clamping the machine housing at mutually opposing sides, and wherein the base member comprises a positive locking contour, and wherein the front side of the machine housing comprises a plug-type receiving member for receiving the positive locking contour of the covering device base member for releasably securing the covering device to the center of the machine housing without application of a tool to the covering device, and wherein the covering device is attachable to and removable from the machine housing without removing the pad tool, and wherein the processing face of the pad tool is substantially rectangular and has a front portion extending from the front side of the housing, the front portion having a front end with two corners, and wherein the at least one protection wall of the covering device comprises a base member portion extending from the base member of the covering device and two lateral member portions extending respectively from the two lateral members of the covering device, the base member portion covering a portion of the front portion of the rectangular processing face and each of the two lateral member portions covering a portion of a respective one of the side flanks of the pad tool, and wherein at least one recess is formed between the base member portion of the protection wall and one of the two lateral member portions of the protection wall, at least one of the two corners of the front end of the processing face protruding through the at least one recess for an edge-side processing operation of the workpiece surface.

2. The portable machine tool according to claim 1, wherein the pad tool protrudes freely counter to the main working direction backwards through a free portion of the covering device or the covering device does not cover a rear portion of the pad tool with respect to the main working direction.

3. The portable machine tool according to claim 1, wherein, on the lateral members of the clamp, locking means for engagement with the machine housing are provided, and wherein the lateral members for securing to the machine housing can be redirected away from each other.

4. The portable machine tool according to claim 1, wherein a gear mechanism for producing the drive movement of the pad tool is arranged between the drive motor and the pad tool.

5. The portable machine tool according to claim 4, wherein the gear mechanism can be switched between at least two of movement types or produces exclusively a rotating movement of the pad tool through a maximum of 30 about a fixed or non-fixed rotation axis.

6. The portable machine tool according to claim 1, wherein the at least one protection wall covers the pad tool with respect to the main working direction and forms the foremost portion of the portable machine tool with respect to the main working direction.

7. The portable machine tool according to claim 1, wherein the at least one protection wall of the covering device has a frontally covering portion arranged between the two corners of the front end of the processing face which protrude in each case through a recess in front of the outer peripheral contour of the covering device.

8. The portable machine tool according to claim 1, wherein the pad tool comprises a carrier plate which is driven by the drive motor.

9. The portable machine tool according to claim 8, wherein the carrier plate has a retention face, the pad tool being secured to the retention face for securing a grinding means or a polishing means thereto.

10. The portable machine tool according to claim 1, wherein the machine housing does not protrude in front of an outer peripheral contour of the covering device or the processing face of the pad tool in the main working direction or the at least one transverse direction.

11. The portable machine tool according to claim 1, wherein a handle element is securely connected to the machine housing or is integral with the machine housing or is arranged in an articulated manner on the machine housing using an articulation arrangement.

12. The portable machine tool according to claim 1, wherein the at least one recess forms a single recess of the covering device.

13. The portable machine tool according to claim 1, wherein the covering device has an arrangement with at least two or more recesses which are arranged beside each other in a row direction or wherein the covering device has exclusively recesses with respect to the transverse working directions.

14. The portable machine tool according to claim 1, wherein the covering device has at least one through-opening or an arrangement of a plurality of through-openings through which a carrier plate of the pad tool can be seen or which are used for the influx of external air at an extraction connection of the portable machine tool.

15. The portable machine tool according to claim 1, wherein the at least one protection wall of the covering device covers the pad tool laterally with respect to the main working direction or with respect to the at least one transverse working direction and does not cover it at the rear.

16. The portable machine tool according to claim 1, wherein the geometry of the envelope or the outer peripheral contour of the covering device, with the exception of in the region of the at least one recess, corresponds to the geometry of the outer peripheral contour of the processing face of the pad tool.

17. The portable machine tool according to claim 1, wherein the geometry of the envelope or the outer peripheral contour of the covering device, with the exception of in the region of the at least one recess, is substantially triangular or rectangular, or circular.

18. The portable machine tool as defined in claim 1, wherein the two lateral member portions of the protection wall extend from the base member portion of the protection wall at an angle of about 90 degrees.

19. The portable machine tool as defined in claim 1, wherein the at least one recess is disposed adjacent the front side of the machine housing opposite the at least one of the extraction connection or the handle portion.

20. A portable machine tool having a pad tool and a drive motor, which is arranged in a machine housing for driving the pad tool to produce an oscillating or rotating or eccentric movement of a processing face of the pad tool, wherein the portable machine tool can be guided with the processing face forwards in a main working direction and laterally transversely relative to the main working direction in at least one transverse working direction for a grinding or polishing operation of a workpiece surface, wherein the machine housing has a front side facing forwards in the main working direction and a rear side opposite the front side, the rear side having at least one of an extraction connection for extracting particles generated by the pad tool or a handle portion to be gripped with a hand, the extraction connection or the handle portion protruding from the rear side of the machine housing in a direction opposite the main working direction, wherein the portable machine tool has, for the pad tool, a covering device, which has at least one protection wall which is arranged upstream of at least one side face of the pad tool which extends beside the processing face with respect to the main working direction or the at least one transverse working direction in order to protect against contact with obstacles, wherein the at least one protection wall of the covering device completely or substantially covers side flanks of the pad tool, and wherein the covering device is a one-piece clamp, the clamp comprising a base member and two lateral members extending rearwardly from the base member, the two lateral members clamping the machine housing at mutually opposing sides, and wherein each of the lateral members comprises a projection disposed at a free end thereof, the projection being received in a plug-type receiving member formed in the machine housing, and wherein the covering device is attachable to and removable from the machine housing without removing the pad tool, and wherein the processing face of the pad tool is substantially triangular and has a front portion extending from the front side of the housing, the front portion having a front end defined by a front tip, and wherein the at least one protection wall of the covering device comprises a base member portion extending from the base member of the covering device and two lateral member portions extending respectively from the two lateral members of the covering device, each of the two lateral member portions covering a portion of a respective one of the side flanks of the pad tool, and the base member portion having at least one recess through which the front tip of the front end of the processing face protrudes for an edge-side processing operation of the workpiece surface.

21. The portable machine tool according to claim 20, wherein the covering device is releasably secured to the machine housing using securing means.

22. The portable machine tool according to claim 21, wherein the pad tool, when the covering device is removed, is without covering of the entire outer periphery or side edge region thereof.

23. The portable machine tool according to claim 21, wherein the covering device can be secured to the machine housing or can be removed from the machine housing without application of a tool to the covering device.

24. The portable machine tool according to claim 20, wherein the at least one protection wall of the covering device completely or substantially covers side flanks of the pad tool or extends as far as the processing face.

25. The portable machine tool according to claim 20, wherein a gear mechanism is arranged between the drive motor and the pad tool, the gear mechanism producing an eccentric or an oscillating or a hypercycloid movement of the pad tool.

26. The portable machine tool according to claim 20, wherein the base member comprises a positive locking contour, and wherein a front side of the machine housing comprises a plug-type receiving member for receiving the positive locking contour of the covering device base member for releasably securing the covering device to the center of the machine housing without application of a tool to the covering device.

27. The portable machine tool according to claim 20, wherein each of the lateral members of the covering device further comprises an inwardly directed guiding contour extending from the base member to the projection of each of the lateral members, each of the inwardly directed contours being received in a guiding receiving member formed in the machine housing.

28. The portable machine tool according to claim 20, wherein the lateral members are configured to be resiliently movable toward and away from each other.

29. The portable machine tool according to claim 28, wherein each of the lateral member projections comprises an inwardly directed locking projection having an inclined introduction member.

30. The portable machine tool as defined in claim 20, wherein the two lateral member portions of the protection wall extend from the base member portion of the protection wall at an angle of more than 90 degrees.

31. The portable machine tool as defined in claim 20, wherein the at least one recess is disposed adjacent the front side of the machine housing opposite the at least one of the extraction connection or the handle portion.

32. A portable machine tool having a pad tool and a drive motor, which is arranged in a machine housing for driving the pad tool to produce an oscillating or rotating or eccentric movement of a processing face of the pad tool, wherein the portable machine tool can be guided with the processing face forwards in a main working direction and laterally transversely relative to the main working direction in at least one transverse working direction for a grinding or polishing operation of a workpiece surface, wherein the machine housing has a front side facing forwards in the main working direction and a rear side opposite the front side, the rear side having at least one of an extraction connection for extracting particles generated by the pad tool or a handle portion to be gripped with a hand, the extraction connection or the handle portion protruding from the rear side of the machine housing in a direction opposite the main working direction, wherein the portable machine tool has, for the pad tool, a covering device, which has at least one protection wall which is arranged upstream of at least one side face of the pad tool which extends beside the processing face with respect to the main working direction or the at least one transverse working direction in order to protect against contact with obstacles, wherein the at least one protection wall of the covering device completely or substantially covers side flanks of the pad tool, wherein the covering device is a clamp, the clamp comprising a base member and two lateral members extending rearwardly from the base member, the two lateral members clamping the machine housing at mutually opposing sides, and wherein the covering device is attachable to and removable from the machine housing without removing the pad tool, and wherein the processing face is substantially triangular or rectangular and has a front portion extending from the front side of the housing, the front portion having a front end with at least one corner region, and wherein the at least one protection wall of the covering device comprises a base member portion extending from the base member of the covering device and two lateral member portions extending respectively from the two lateral members of the covering device, the two lateral member portions covering a portion of a respective one of the side flanks of the pad tool, and the base member portion having at least one recess through which at least one of the at least one corner region of the front end of the processing face protrudes for an edge-side processing operation of the workpiece surface.

33. The portable machine tool according to claim 32, wherein the base member comprises a positive locking contour, and wherein the front side of the machine housing comprises a plug-type positive locking receiving member for receiving the positive locking contour of the covering device base member for releasably securing the covering device to the center of the machine housing without application of a tool to the covering device, and wherein each of the lateral members comprises a projection disposed at a free end thereof, the projection being received in a guiding projection receiving member formed in the machine housing.

34. The portable machine tool according to claim 32, wherein the covering device is a one-piece clamp.

35. The portable machine tool as defined in claim 32, wherein the at least one recess is disposed adjacent the front side of the machine housing opposite the at least one of the extraction connection or the handle portion.

Description

BRIEF DESCRIPTION OF THE DRAWINGS

(1) An embodiment of the invention is explained below with reference to the drawings, in which:

(2) FIG. 1 is a perspective oblique view of a portable machine tool and an associated covering device in the state separated from each other,

(3) FIG. 2 shows the portable machine tool according to FIG. 1 with the covering device arranged thereon,

(4) FIG. 3 shows the portable machine tool according to the above Figures with a different covering device in a state separated from each other,

(5) FIG. 4 shows the arrangement according to FIG. 3, wherein the covering device is arranged on the portable machine tool,

(6) FIG. 5 shows the portable machine tool according to the above Figures with another covering device in a state separated from each other, and

(7) FIG. 6 shows the portable machine tool according to FIG. 5 with the covering device arranged thereon.

DETAILED DESCRIPTION

(8) A portable machine tool 10 according to the drawing has a machine housing 11 in which a drive motor 12 for driving a disc tool 30 is arranged. A gear mechanism 14, for example, an eccentric gear mechanism for producing a hypercycloid movement of the disc tool 30 relative to the machine housing 11 or the like may be provided between the drive motor 12 and the disc tool 30. The disc tool 30 is, for example, arranged on an output 13 of the gear 14. The gear mechanism 14 may also bring about a speed reduction or other speed change between the output of the drive motor 12 and the output 13 thereof.

(9) The machine housing 11 may be gripped using a handle portion 15, for example, enclosed with a hand, wherein at a front region of the handle portion 15 a drive switch 16 for switching on and switching off the drive motor 12 is provided.

(10) Alternatively, however, it is also possible for an in particular rod-like handle element 15a to be supported in an articulated manner with the machine housing 11 using an articulation arrangement, for example, an articulation arrangement having one or more pivot bearings 111. Consequently, the machine housing may, for example, using the articulation arrangement pivot relative to the handle element about one or more pivot axes. In particular, the portable machine tool may be a wall grinder or a ceiling grinder.

(11) The drive motor 12 itself is in turn arranged in a drive portion 17 of the machine housing 11. The disc tool 30 is arranged at a base region 18 of the machine housing 11 remote from the handle portion 15, in the drawing at the bottom on the drive portion 17. With a processing face 31 of the disc tool 30, a workpiece surface O of a workpiece W can be processed, for example, in the context of a grinding processing operation or a polishing processing operation. The operator may, for example, grip the portable machine tool 10 on the handle portion 15 and thus guide the disc tool 30 with the processing face 31 thereof over the workpiece surface O, for example, directly forwards in a main working direction HA or also transversely to the side with respect to the main operating direction HA to the right in a transverse working direction QR and to the left in a transverse working direction QL. In this instance, for example, circular movements on the workpiece surface O are also readily possible.

(12) On the processing face 31, a processing surface may be provided integrally, for example, a coating with a corresponding granulation, an abrasive web or the like. However, preferably in the region of the processing face 31, a retention means, for example, a hook and loop retention means, an adhesive layer or the like, is provided in order to retain a grinding sheet or another grinding means 40, for example, a knitted grinding fabric which then provides the actual processing face 31. The processing face 31 may thus be formed by a replaceable grinding means or polishing means. Using the grinding means 40, the workpiece surface O may, for example, be ground. Alternatively, a polishing disc or similar other polishing means, for example, a knitted polishing fabric, would also be readily possible.

(13) In the region of the output 13 or above the carrier plate 33, within the machine housing 11 there is provided an extraction chamber 19 which cannot be seen in the drawing and which is connected in terms of flow to an extraction connection 21 of the machine housing 11. Via the extraction connection 21, dust or other similar particles produced by a workpiece processing operation can be extracted from the region of the disc tool 30 which has for this purpose, for example, lateral influx openings 32 and influx openings which communicate with the lower side thereof (schematically illustrated).

(14) In this instance, the disc tool 30 is at least partially securely connected to the output 13, that is to say, to a carrier plate 33. However, it would also be possible for the output 12 to have a tool receiving member, for example, with bayonet contours, a screw receiving member or the like, to which the carrier plate 33 can be releasably secured.

(15) On a retention face 35 of the carrier plate 33, a cushion 34, for example, a pad, is arranged. The cushion comprises resilient material, for example, foam, rubber or the like. The cushion 34 is, for example, screwed, adhesively bonded or securely connected in some other manner to the carrier plate 33, but preferably so as to be able to be replaced. The grinding means 40 in contrast may be releasably secured to a securing face 36 of the cushion 34 which, for example, has hook and loop connection means or the like, that is to say, can be readily replaced in the event of wear or another quality requirement.

(16) The disc tool 30 protrudes forwards with a portion 37 with respect to the main working direction HA, with portions 38 to the side with respect to the transverse working directions QR and QL and with a portion 39 to the rear counter to the main working direction HA in front of an outer peripheral contour 20 of the machine housing in the region of the disc tool 30. Consequently, the disc tool 30 is in a manner of speaking exposed, which in the state of the portable machine tool 10 illustrated in FIG. 1 facilitates edge-side processing of the workpiece surface O. The portion 37 protrudes, for example, in front of a front side 22 of the machine housing 11, the portions 38 project to the side, in front of transverse sides 23 of the machine housing 11. Although the rear portion 38 is to a degree protected by the extraction connection 21, it nonetheless protrudes in front of a rear side 24 of the machine housing 11.

(17) In the so-to-speak uncovered state illustrated in FIG. 1, the disc tool 30 can be guided with the processing face 31 thereof in the main working direction HA forwards as far as an obstacle HV which protrudes in front of the workpiece surface O until it strikes the obstacle HV with the front side face 47 thereof. Also to the side, in the transverse working directions QR and QL, the disc tool 30 can be guided towards such obstacles HR or HL until it strikes this obstacle HR or HL with the lateral side faces 48 thereof. Even towards the rear, that is to say, counter to the main working direction HA, an edge-side processing is readily possible so that the processing face 31 can be guided until the disc tool 30 strikes with a rear side face 49 an obstacle HH which protrudes in front of the workpiece surface O, for example, a skirting board or the like.

(18) However, the operator will generally wish to prevent such a collision in order not to damage the sensitive side flanks of the disc tool 30 and the obstacles themselves. This is because it can be seen that the resilient cushion 34 and also the narrow sides of the grinding means 40 are sensitive and can become damaged when striking such an obstacle HV, HR or HL. Furthermore, it is also possible for the narrow sides of the carrier plate 33 which preferably comprise a rigid material, in particular a hard plastics material, metal, to be able to damage the obstacle HV, HR or HL. In addition, the processing face 31 of the disc tool 30 has a polygonal, in this instance rectangular structure, wherein straight corner regions 41 of the disc tool 30 which have corners 43 or outer corners with respect to the main working direction HA and the transverse working directions QR and QL, are exposed and consequently particularly at risk of striking obstacles.

(19) A similar situation arises with a portable machine tool 110 according to FIGS. 3 and 4 which in place of the disc tool 30 has a triangular disc tool 130. The disc tool 130 has, for example, a substantially triangular processing face 131 and a similarly substantially triangular carrier plate 133 on which a triangular cushion 134 is retained. With a portable machine tool 210 according to FIGS. 5 and 6 with a round disc tool 230, a similar problem also arises in that the respective disc tool 130, 230 tangentially collides with obstacles and is thereby damaged itself or damages the obstacle HV, HR or HL or both.

(20) Both a portion 137 which protrudes forwards and lateral portions 138 and a rear portion 139 protrude in front of the projection of the machine housing 11 onto the workpiece surface O and are thus exposed. The protruding portion 137 forms a tip 143 or a tip region 141 which in a state exposed forwards in the direction of the main working direction HA protrudes in front of the machine housing 11 or the front side 22 thereof. From the tip region 141, side faces 248 of the disc tool 130 extend to the rear portion 139 on which a rear, end-side side face 149 is provided. The side faces 148, 149 may in contact with obstacles which protrude, for example, in front of the workpiece surface O, readily become damaged.

(21) The disc tool 230 has a substantially round, circular outer contour and processing face 231. Also round, in particular circular, are a carrier plate 233 of the processing tool or disc tool 230 and a cushion 234 which is arranged on the carrier plate 233. Although the disc tool 230 is somewhat more compact than the disc tools 30, 130, it is completely exposed with respect to the machine housing 11 and in particular in the event of edge-side processing of the workpiece surface O at risk by obstacles which protrude upwards at that location.

(22) The disc tool 230 protrudes, for example, forwards, with a front portion 237 in front of a front side 22 of the machine housing 11. To the side the disc tool 230 also protrudes in a manner of speaking laterally in front of the transverse sides 23 of the machine housing 11, that is to say, with lateral portions 238. A rear portion 239 which protrudes in front of the rear side 24 of the machine housing or the outer peripheral contour 20 is in contrast arranged substantially below the extraction connection 21 so as to be protected. Nonetheless, at least the lateral and front portions 238, 237 of the disc tool 230 are also exposed and at risk of striking obstacles, wherein, on the one hand, the disc tool 230, on the other hand, the obstacle HV, HR or HI may become damaged.

(23) In order to overcome these problems, there are provided covering devices 60, 160, 260 which if necessary can be secured to the machine housing 11 in order to cover the disc tool 30, 130, 230.

(24) The covering devices 60, 160, 260 have base members 61, 161, 261, which each have a base member 62, 162, 262 from which side members 63, 163, 263 and 64, 164, 264 protrude and thus define a receiving member 65 in which the machine housing 11 can be in a manner of speaking inserted orin other wordswith which the covering device 60, 160, 260 can be fitted to the machine housing 11 in an insertion direction E. The side members 63, 163, 263 and 64, 164, 264 are then in abutment with the transverse sides 23 and the base members 62, 162, 262 at the front side 22 of the machine housing 11. A plug type connection is thereby possible between the covering devices 60, 160, 260 and the machine housing 11.

(25) On the outer peripheral contour 20 of the machine housing 11 there is provided a plug-type receiving member 26 as a component of securing means 25 which serves to receive plug-type projections 66 which are formed by the side members 63, 163, 263 and 64, 164, 264.

(26) The covering devices 60, 160, 260 are configured in the manner of clamps 85 which can be fitted in a clamp-like manner to the machine housing 11.

(27) For a central centering of the covering devices 60, 160, 260 on the machine housing 11, there are, for example, provided positive-locking contours 67, for example, positive-locking receiving members, on the base members 62, 162, 262 which in the state in which the covering devices 60, 160, 260 are fitted to the machine housing 11, are in engagement with positive-locking counter-contours 27 at the front side 22 of the machine housing 11.

(28) The plug type connection between the machine housing 11 and covering device 60, 160, 260 comprises guiding receiving members 28 which are provided on the machine housing 11 and into which guiding contours 68 which protrude inwards in the direction towards the receiving member 65 protrude. The guiding contours 68 engage in a positive-locking manner in the guiding receiving members 28 when the respective covering device 60, 160, 260 is fitted to the machine housing 11. Consequently, the covering devices 60, 160, 260 are retained in a positive-locking manner transversely relative to the insertion direction E.

(29) A retention with respect to the insertion direction E is ensured by an engagement with locking means which have locking projections 69 on the free end regions of the lateral members 63, 163, 263 and 64, 164, 264 which engage in locking receiving members 29 at the transverse sides 23 of the machine housing 11 or at the longitudinal end regions of the guiding receiving members 28 when the respective covering device 60, 160, 260 is fitted to the machine housing 11. In this instance, it is advantageous for the lateral members 63, 163, 263 and 64, 164, 264 to be able to be redirected in a direction away from each other or in a direction for widening the receiving member 65 in a flexible or resilient manner and, when the locking projections 69 are opposite the locking receiving members 29, to move towards each other again.

(30) An introduction of the locking projections 69 of the covering devices 60, 160, 260 in the plug type receiving member 26 is facilitated by inclined introduction members 74 which are provided at the free end regions of the lateral members 63, 163, 263. A release of the catch projections 69 is advantageously facilitated by means of gripping elements 75 which are provided in the region of the catch projections 69 on the lateral members 63, 163, 263 and 64, 164, 264.

(31) Consequently, a simple assembly of the covering devices 60, 160, 260 on the machine housing 11 is possible. They can thus be readily removed when they are not required, but may also remain a relatively long time on the machine housing 11 since an edge-side processing of the workpiece surface O is also possible with a covering device 60, 160, 260 which is mounted on the machine housing 11.

(32) The covering device 60 has a covering wall 70 which with a covering portion 72 covers the carrier plate 33 from the side of the machine housing 11, in the drawing from above, and additionally has protection walls 77, 78 which can also be referred to as protection wall portions. On the covering portion 72, there is provided a wall region 73 which protrudes in the manner of a collar and which delimits the receiving member 65.

(33) The protection wall 77 is arranged upstream of the side face 47 of the disc tool 30, that is to say, upstream in the main working direction HA of the side face 47 so that it protects it from frontal contact with the obstacle HV. The protection walls 78 are arranged upstream of the side faces 48 with respect to the transverse working directions QR and QL so that they can protect the disc tool 30 from contact with the lateral obstacles HR and HL.

(34) Nonetheless, an edge-side processing of the workpiece surface O is readily possible. Between the protection walls 77, 78 there is provided a recess 71 through which a corner region 41 of the disc tool 30 in front of an outer peripheral contour 80 which in the region of the recesses 71 is not rectangular but instead has corresponding recesses or indentations 81 in which the processing face 31 is provided in a manner of speaking free and without any covering towards the side for an edge-side processing of the workpiece surface O. In the corner regions 41, a side edge region 42 of the processing face 31 is free as far as the side face 47 and side face 48 without a front-side covering by the covering device 60 so that the disc tool 30 with the corner regions 41 can be brought up to, in an extreme case, direct contact with the obstacle HV or to the side with the obstacles HR and HL. However, the operator will generally attempt to process the workpiece surface O with the processing face 31 in the corner regions 41 without such direct contact with the obstacles HV, HR and HL occurring.

(35) Furthermore, a rear region of the processing face 31 in the main working direction HA is freestanding, that is to say, in the rear portion 39. It is not covered by the covering device 60 so that per se the rear side face 49 is ready for an edge-side processing of the workpiece surface O. However, it can be seen that the portion of the handle portion 15 which protrudes backwards over the rear side 24 of the machine housing 11 and the extraction connection 21 located therebelow, in this instance an extraction pipe, impede operation at the rear.

(36) The recesses 71 have narrow side walls 79 which extend from the protection walls 77, 78 as far as the covering portion 72 and between which a narrow side wall 76 extends on the covering portion 72. From above, therefore, even the carrier plate 33 in the corner regions 41 can be seen and consequently also the processing face 31 which extends with the same surface extent.

(37) The covering device 160 of the portable machine tool 110 has a substantially triangular outer peripheral contour 180 in which an indentation 181 is provided in the tip region 141. Consequently, the tip 143 protrudes freely in front of the covering device 160 so that portions of the side faces 148 which are located in the region of the indentation 181 and consequently the side edges of these portions of the side faces 148 beside the processing face 131 are ready and free for an edge-side or corner processing operation of the workpiece surface O.

(38) Also the rear portion 133, in any case the rear side face 49 and the side edge of the processing face 131 at that location are free, that is to say, are not covered by the covering device 160 so that the rear portion 133 of the disc tool 130 is ready for an edge-side processing operation of the workpiece surface O.

(39) The base member 161 of the covering device 60 has a covering portion 172 which covers the disc tool 30 with the exception of a recess 171 in the region of the tip 143 or the tip region 141. Protection walls 178 which protrude downwards from the covering portion 172 in front of the side faces 143 substantially cover the side faces 148 with the exception of the tip region 141. Consequently, an edge protection or side impact protection is provided there for the sensitive disc tool 130 or the sensitive obstacles HL, HR and HV which could potentially be damaged by the disc tool. However, a front-side cover, for example, in the manner of the side wall 77 of the covering device 60 is not present.

(40) In the recess 171 a side edge region 142 of the disc tool 130 protrudes freely in front of the outer peripheral contour 180.

(41) The recess 171 has narrow side walls 179 in the region of the protection walls 178 and a narrow side wall 176, where it adjoins the covering portion 172.

(42) Furthermore, there are advantageously provided through-openings 190, through which, for example, the carrier plate 133 or the disc tool 130 can be seen from above. The through-openings 190 may, however, also be used to allow the selective influx of external air which is extracted at the extraction connection 21.

(43) The covering device 260 leaves a rear portion 239 of the disc tool 260 free. The lateral portions 238 and the front portion 239 are, however, substantially covered by the covering device 260. On the base member 261 thereof, in particular a covering portion 272, influx openings 290 are provided, for example, for the influx of external air or for better visibility of the disc tool 330. In front of the covering portion 271 there protrudes a front protection wall 277 of the covering device 260 which covers the front portion 237 of the disc tool 230. Between the front protection wall 277 and protection walls 278 which partially cover the side faces 248 of the disc tool 230, there are provided recesses 271 through which a side edge region 242 of the disc tool 230 and consequently the processing surface 231 freely protrudes. Consequently, with an edge portion 241 of the disc tool 230 which is arranged in one of the recesses 271, the workpiece surface O can be processed at the edge side, for example, in the region of the obstacles HR or HL.

(44) The recesses 271 (only one recess 271 could also be provided, in one of the side members 263 or 264) have, for example, narrow side walls 279 in the region of the protection walls 277, 278 between which a narrow side wall 276 extends along the covering portion 272.

(45) In FIG. 6, another embodiment of an alternative of the covering device 260 is illustrated, that is to say, a covering device 360. This has, for example, a plurality of recesses 371 which are angularly spaced apart over the outer periphery thereof and through which in a manner not described in greater detail edge regions of the disc tool 230 protrude freely in front of the outer peripheral contour of this covering device 360.