GB2397797A

GB2397797A - Hand tool machine

Info

Publication number: GB2397797A
Application number: GB0401637A
Authority: GB
Inventors: Adolf Zaiser
Original assignee: Robert Bosch GmbH
Current assignee: Robert Bosch GmbH
Priority date: 2003-01-29
Filing date: 2004-01-26
Publication date: 2004-08-04
Anticipated expiration: 2024-01-26
Also published as: GB0401637D0; CN100448635C; DE10303543A1; DE10303543B4; CN1519089A; GB2397797B

Abstract

A hand tool machine, such as a hand-held circular saw, having a rotating cutting disk 11, such as a saw blade, rotatably mounted on a carrier 12 with a handle (17, fig.1), wherein the carrier 12 is pivotally mounted on a base plate 16 which has a protective hood 15 connected to it and a through-slot for the cutting disk 11. Apparatus 20 for setting the depth of cut comprises a stop 21 connected to a guide element (35, fig.5) which is situated displaceably in a guide channel 34 in the protective hood 15 and is clamped in the desired position by means of a fixing member 27 projecting from the protective hood 15, and a counterstop 22 on the carrier 12 that interacts with said stop 21. A depth scale (33, fig.4) is mounted along the guide channel 34 on the outside of the protective hood 15.

Description

Hand tool machine

Background art

The invention proceeds from a hand tool machine, in particular a handheld circular saw, according to the preamble of claim 1.

In a commercially available, known hand tool machine of this type with a circular saw blade as a cutting disk, described in short as a plunge saw, the depth-of-cut setting apparatus comprises a gauge, which has a depth scale disposed thereon and is bent into the shape of an arc segment and fastened on the base plate in such a way that the centre of the circle of the arc segment lies on the swivelling axis of the carrier. The gauge has a centrally disposed longitudinal slot, in which a stop is displaceable and fixable in a desired basic position by manually tightening a clamping screw, which extends through the slot and is supported by its screw head and by a wing nut screwed thereon at mutually remote sides of the gauge. In order to introduce a saw cut into a workpiece, the plunge saw is placed by its base plate onto the workplace and, with the circular saw blade rotating, the handle is gradually swivelled downwards. The rotating circular saw blade therefore pushes forward through the through-slot in the base plate and beyond the base plate and penetrates the workpiece. As soon as the counterstop formed on the carrier comes to rest against the preset stop, the desired depth of cut has been reached, at which the saw cut is then effected by forward feed of the plunge saw.

Advantages of the invention The hand tool machine according to the invention having the features of claim 1 has the advantage of a very good view of the depth scale for setting the desired depth of cut as well as an attractively shaped, aesthetic appearance of the setting apparatus combined with economical manufacture. In contrast to the known freestanding, curved gauge, the circular arc guide of the stop may be followed extremely precisely and so a comfortable initial depth-of-cut setting may be achieved without any risk of jamming. Even under rugged operating conditions the function of the setting apparatus is not adversely affected. With a low conversion outlay the hand tool machine may also be used for stationary operation, e.g. as a circular saw bench. By raising the cutting disk designed e.g. as a circular saw blade simple mitre cuts, e.g. on picture frames and flooring strips, may be effected from below, wherein the loosened stop is usable as a handle. Furthermore, sawing may be carried out at a permanently set depth of cut, wherein when setting the depth of cut, a good view of the depth-of-cut scale is once more guaranteed.

Advantageous developments and improvements of the hand tool machine indicated in claim 1 are possible by virtue of the measures outlined in the further claims.

According to an advantageous embodiment of the invention the guide channel is introduced in the, in working direction, front end face of the protective hood and the depth scale is disposed on a lateral surface of the protective hood. By said means, an ergonomically advantageous operation of the setting apparatus with a good view of the depth scale is achieved.

According to an advantageous embodiment of the invention the guide channel and the guide element situated displaceable in the guide channel have a T-shaped profile.

The fixing member for fixing the guide element in the guide channel comprises a threaded pin, which extends through the stop, is firmly connected to a turning handle, is screwable in a threaded bore in the guide element and provided with a clamping shoulder, which lies frontally against the stop.

Given said structural configuration, the stop may be infinitely adjusted to a desired depth of cut at the depth scale and is held locked against displacement in the set position.

According to an advantageous embodiment of the invention the stop comprises a middle piece supported against the end face of the protective hood and having an axial bore for passage of the threaded pin, a stop limb overlapping the lateral surface of the protective hood and projecting into the swivelling path of the counterstop, and a depth-of- cut indicator projecting at the other lateral surface of the protective hood. For fixing the stop on the protective hood, the clamping shoulder on the threaded pin is supported against the end face of the middle piece.

The hand tool machine according to the invention is very easy to convert for stationary operation, when it is used e.g. as a circular saw bench and to said end is fastened by its base plate to the underside of a workbench top. For stationary operation of the hand tool machine, according to an advantageous embodiment of the invention an additional stop is provided, which is inserted instead of the stop for manual operation into the guide channel. In the case of this stop, the length of the middle piece is as great as possible, but considerably larger than the transverse dimensions of the middle piece, so that as a whole the stop with the turning handle of the fixing member projects at a distance from the protective hood and may be gripped in an ergonomically advantageous manner. This stop is otherwise designed like the previously mentioned stop and comprises in addition a securing element disposed on the stop limb for positive engagement into a frontal opening in the counterstop. When the stop is displaced, the counterstop is simultaneously carried along and via the counterstop the carrier is displaced, so that by raising the saw blade to a greater or lesser extent above the surface of the workbench top the depth of cut is fixed. When clamping of the stop is cancelled by loosening the turning handle on the fixing member, the stop, which is connected to the counterstop so as to be locked against displacement and rotation, may be gripped, and the stationary hand-held circular saw may be used to effect e.g. mitre cuts from below by swivelling the saw blade continuously upwards by means of the stop.

According to an advantageous embodiment of the invention there is provided between the protective hood and the stop an additional guide comprising a guide groove, which is closed at one end and extends at a radial distance from the guide channel, as well as a locking lug, which engages into the guide groove. Guide groove and locking lug are formed in a lateral surface of the protective hood and on the stop or vice versa. Guide groove and locking lug are used to hold the stop captive on the protective hood when the fixing member is loosened and the guide piece is therefore situated loosely in the guide channel. For introducing the locking lug into the guide groove, the latter is provided with an open- ended inlet extending at right angles thereto.

When the guide groove is disposed in a lateral surface of the protective hood and the locking lug is disposed on the stop, the locking lug may be used to prevent the latching of the carrier that is usually provided in such a hand tool machine once the cutting disk is fully retracted into the protective hood. Particularly during stationary operation of the hand tool machine this carrier latching is very troublesome and has the effect of impeding an optimum work flow.

According to an advantageous embodiment of the invention there is provided on the counterstop a precision adjustment screw, which is screwable in the counterstop and supported by its free screw end against the stop. This adjustment screw enables precision adjustment of the position of the cutting disk relative to the depth scale or is used to displace the depth stop in the range of tenths of a millimetre.

According to an advantageous embodiment of the invention there is disposed on the scale a symbol for a cutting disk exchange position, which indicates a relative position between protective hood and carrier that is preferred for the cutting disk exchange. When the carrier is transferred into this position, the clamping flange of the cutting disk appears in a window of the protective hood and may be comfortably loosened.

Drawings There now follows a detailed description of the invention with reference to an embodiment, which is illustrated in the drawings. The drawings show: Figs. 1 and 2 in each case a side view of a plunge saw with a depth-of-cut setting apparatus

according to prior art in idle position

(Fig. 1) and in working position with a maximum depth of cut (Fig. 2), Fig. 3 in a cut-out style a side view of a plunge saw with a depth-of-cut setting apparatus according to the invention, Fig. 4 an opposite view of the plunge saw in Fig. Fig. 5 a section along the line V - V in Fig. 3, Figs. 6 and 7 in each case a view identical to Fig. 5 of a depth-of-cut setting apparatus according to two further embodiments.

Description of the embodiments

The known hand-held circular saw in the form of a so-called plunge saw, which is illustrated in side view in Figs. 1 and 2, comprises a circular saw blade 11, which is rotatably mounted on a carrier 12 and driven by an electric motor 13. The electric motor 13 preferably in the form of a geared motor is likewise fastened to the carrier 12. The carrier 12 is pivotally mounted by means of a pivot bearing arrangement 14 on a protective hood 15, which covers the saw blade 11 completely or partially depending on the swivel position of the carrier 12. The protective hood 15 at its underside is rigidly connected to a base plate 16, which has a through-slot for the saw blade 11. Fastened to the carrier 12 is a handle 17, which is used to manipulate the plunge saw and on which an ON/OFF switch 18 for the electric motor 13 is disposed. For a sawing operation, the plunge saw is placed by its base plate 16 onto a workpiece, and after switching on the electric motor 13 the carrier 12 is swivelled downwards by means of the handle 17, with the result that the saw blade 11 passes progressively through the through-slot in the base plate 16 and penetrates the For limiting the depth of cut of the saw blade 11 a depth of-cut setting apparatus 20 is provided, which blocks the swivelling operation of the carrier 12 upon attainment of the desired depth of cut of the saw blade 11. This depth of-cut setting apparatus 20 comprises a stop 21, a counterstop 22 interacting therewith, and a depth scale, which is not visible in Figs. 1 and 2 and at which the depth of cut may be read. The depth scale is mounted on a curved gauge 24, which is fastened by means of a screw connection 25 to the base plate 16, namely in such a way that the centre of the circle of the gauge 24, which describes a circular arc segment, coincides with the swivelling axis of the pivot bearing arrangement 14. The gauge 24 has a centrally disposed longitudinal slot 26, in which the stop 21 is displaceable along the depth scale and fixable by means of a fixing member 27 given a scaling corresponding to the desired depth of cut. The fixing member 27 is formed by a head screw 28, which extends with its screw shank through the longitudinal slot 26 and a bore in the stop 21 and onto the threaded shank of which a wing nut 28 is screwed. For fixing the stop 21, the wing nut 28 supported on the stop 21 is screwed onto the threaded shank to such an extent that the screw head is applied against the gauge 24 and the stop 21 is clamped tightly between the gauge 24 and a clamping shoulder on the wing nut 28.

When the plunge saw is not in use or before the beginning of a sawing operation, the carrier 12 with the handle 17 formed thereon is in the position of maximum upward swivelling, as shown in Fig. 1. In this position, the saw blade 11 is fully retracted into the protective hood 15 and the carrier 12 is locked against swivelling by means of a releasable detent apparatus 29. This detent apparatus 29 has a spring-loaded safety bolt 30, which in the previously mentioned basic position of the carrier 12 is supported against the upper end of the gauge 24 and hence blocks a swivelling movement of the carrier 12. By means of a release button 31 the safety bolt 30 is swivelled off the end of the gauge 24 and so the carrier 12 is released for the swivelling movement. If the electric motor 13 is then switched on by means of the ON/OFF switch 18, the rotating saw blade 11 may be lowered continuously downwards, wherein it penetrates the workpiece. The downward swivelling movement may be continued until the housing stop 22 formed on the carrier 12 rests against the stop 21. The depth of cut in the workpiece 10 that is desired by presetting the stop 21 on the gauge 24 is thereby achieved. In the view of Fig. 2, this depth of cut is the maximum possible depth of cut since the stop 21 is fixed at the bottom end of the depth scale.

As the plunge saw according to the invention illustrated in a cut-out style in two different side views in Figs. 3 and 4 and serving as an embodiment of a general hand tool machine with a rotating cutting disk corresponds in its fundamental, structural design to the known plunge saw according to Figs. 1 and 2, identical components are characterized by identical reference characters and reference is made to the corresponding descriptions pertaining to Figs. 1 and 2.

With regard to the depth-of-cut setting apparatus 20 the embodiment according to Figs. 3 and 4 of the plunge saw according to the invention is structurally redesigned. The depth-of-cut setting apparatus 20 once more comprises a stop 21 and a counterstop 22 interacting therewith and formed on the carrier 12, as well as a depth scale 33 (Fig. 4), along which the stop 21 is displaceable and fixable in a desired position. For this purpose, a guide channel 34 with a T-shaped profile is incorporated in the protective hood 15. The T-shaped profile of the guide channel 34 is visible in the sectional view in Fig. 5. The guide channel 34 is in said case incorporated into the, in working direction of the plunge saw, front end face 151 of the protective hood 15, namely in such a way that the middle part of the T-shaped profile opens freely in the end face.

The guide channel 34, which runs out freely at the upper side 152 of the protective hood 15, accommodates in a displaceable manner a guide element 35 likewise having a T- shaped profile, which may be introduced from the upper side 152 of the protective hood 15 into the guide channel 34.

The guide element 35 displaceable in the guide channel 34 is connected to the stop 21 and may be tightly clamped by means of the fixing member 27 at any desired point in the guide channel 34. The depth scale 33 for setting the depth of cut of the saw blade 11 is mounted along the guide channel 34 outside on the lateral surface of the protective hood 15, as is shown in Fig. 4. The depth scale 33, like the guide channel 34, is curved in the shape of a circular arc, wherein the centre of both circular arcs lies in the swivelling axis of the pivot bearing arrangement 14 (not shown in Figs. 3 and 4) of the carrier 12 on the protective hood 15. In Fig. 3, the stop 21 is fixed by means of the fixing member 27 at the lowermost position of the depth scale 33 and so the maximum depth of cut is set. In addition, Fig. 3 shows the stop 21 once more in a displacement position at the upper end of the guide channel 34. In this position of the stop 21, the swivelling movement of the carrier 12 is already blocked before the saw blade 11 is able to penetrate the workpiece.

As is evident from the sectional view in Fig. 5, the fixing member 27 comprises a threaded pin 37, which extends through the stop 21 and is firmly connected to a turning handle 36 and is screwable in an axial threaded bore 38 in the guide element 35. Formed on the underside of the turning handle 36 or on the threaded pin 37 is a radially projecting clamping flange 39, which is supported against the stop 21 and, when the threaded pin 37 is screwed into the threaded bore 38, clamps the stop 21 tightly against the end face 151 of the protective hood 15. The stop 21 comprises a middle piece 211, which is supported against the end face 151 and has an axial stepped bore 40, and an integrally formed stop limb 212, which overlaps the lateral surface of the protective hood 15 and projects into the swivelling path of the counterstop 22 formed on the carrier 12. There is further integrally formed on the middle piece 211 a depth-of-cut indicator 41, which slightly overlaps the protective hood 15 at the side remote from the stop limb 212 and upon displacement of the stop 21 in the guide channel 34 slides along the depth scale 33. At the depth scale 33 the depth-of-cut indicator 41 in said case marks the depth of cut achieved as soon as the counterstop 22 strikes against the stop 21 fixed at said marking.

As Fig. 4 reveals, the depth-of-cut indication "30 mm" is surrounded by a symbol 42 and thereby made particularly conspicuous. If the stop 21 is set to this depth of cut "30 mm", then, when the counterstop 22 abuts the stop 21, the carrier 12 is situated relative to the protective hood in a position, in which the saw blade exchange may be effected. In this position of the carrier 12, the clamping flange fixing the saw blade 11 appears in a window 43 (Fig. 4) cut out of the protective hood 15 and may be detached without difficulty.

As is indicated by dashed lines in Fig. 5, there may additionally be integrally formed on the stop limb 212 a locking lug 44, which engages in a longitudinally displaceable manner into a guide groove 45 disposed in the protective hood 15. The guide groove 45 likewise in the shape of a circular arc segment is introduced concentrically with the guide channel 34 in the lateral surface of the protective hood 15 so that the centre of the circle of the arc-shaped guide groove 45 likewise lies on the swivelling axis of the pivot bearing arrangement. The guide groove 45 - as is evident from Fig. 3 - is closed at the end, wherein the end facing the upper side 152 is situated a distance in front of the upper side 152 of the protective hood 15. When in the loosened state of the fixing member 27 the stop 21 is displaced upwards, the locking lug 44 strikes against the end of the guide groove and prevents further movement of the stop 21, thereby preventing the guide element 35 from escaping from the guide channel 34 at the upper side 152 of the protective hood 15. To remove the stop 21, the threaded pin 37 of the fixing member 27 has to be fully unscrewed from the guide element 35. The locking lug 44 on the stop 21 may then be withdrawn from the guide groove 45 through an inlet 46 (Fig. 3), thereby allowing the stop 21 to be removed from the protective hood 15. The inlet 46 in the form of a groove is disposed in Fig. 3 at or near the upper end of the guide groove 45 and opens at one end in the guide groove 45 and at the other end in the end face 151 of the protective hood 15. The inlet 46 may equally well be provided in an identical alignment at the lower end or at any other point of the guide groove 45. To reattach the stop 21 to the protective hood 15, the guide element 35 has to be introduced into the guide channel 34 and the locking lug 44 has to be threaded via the inlet 46 into the guide groove 45. The threaded pin 37 is then passed through the stepped bore 40 in the middle piece 211 of the stop 21 and screw-fastened in the threaded bore 38 in the guide element by rotating the turning handle 36.

The stop 21', which is illustrated in Fig. 6 in an identical sectional view to Fig. 5 and is fixed to the front end 151 of the protective hood 15 by means of the fixing member 27, is used instead of the stop 21 in Fig. 5 during so-called stationary operation of the plunge saw.

During stationary operation - in a known manner - the plunge saw is screwfastened by its base plate 16 to the underside of a workbench top and the saw blade 11 protrudes through a slot in the workbench top from the surface of the workbench top. The projecting height of the saw blade 11 is in said case set by means of the swivel angle of the carrier 12 relative to the protective hood 15. For this stationary operation of the plunge saw, the stop 21 is replaced by the stop 21' according to Fig. 6, which is of an identical construction to the stop 21 in Fig. 5 and is modified merely in respect of its middle piece 211' and its stop limb 212'. The stop 21' is connected in the same manner as the stop 21 by the fixing member 27 to the guide element 35 and may be tightly clamped in the same manner by rotating the turning handle 36 on the protective hood 15.

The middle piece 211' is of a very long construction, wherein its axial length is greater than its transverse dimensions. In said case, the middle piece 211' is constructed with the maximum structurally tenable length to allow ergonomic handling of the stop 21'.

Formed integrally on the stop limb 212' is a securing element 47, which engages positively into the counterstop 22 and locks it against any swivelling movement. As is further not shown in Fig. 3, for this purpose the counterstop 22 projecting like a pin in radial direction on the carrier 12 is of a rectangular, hollow design in order to hold the securing element 47 locked against tilting and rotation. During insertion of the stop 21', which is inserted in the same manner as previously described for the stop 21 by its locking lug 44 through the inlet 46 into the guide groove 45, the securing element 47 engages into the counterstop 22 and fixes it to the stop 21'. The desired depth of cut of the saw blade 11, i.e. the projecting height of the saw blade 11 above the surface of the workbench top, is set in that the stop 21' is clamped tightly in the corresponding position on the depth scale 33 by rotating the turning handle 36. In the loosened state of the fixing member 27, the stop 21' may be used to swivel the carrier 12 manually from below in an upward direction, with the result that the saw blade 11 is raised to an increasing extent above the surface of the workbench top.

By virtue of this free swivelling of the carrier 12 mitre cuts may be effected e.g. picture frames or flooring strips may be cut.

The locking lug 44, which is provided on the stop limb 212' of the stop 21' and engages into the guide groove 45 in the protective hood 15, additionally has the extra function of blocking the initially mentioned detent apparatus 29, which is also provided in the plunge saw according to Fig. 3 for latching of the carrier 12 when the saw blade 11 is swivelled fully into the protective hood 15, for stationary operation of the plunge saw. For this purpose, the end of the guide groove 45 situated near the upper side 152 of the protective hood 15 is positioned in the protective hood in such a way that during swivelling of the saw blade (and with previous loosening of the fixing member 27 on the stop 21') the locking lug 44 strikes against the end of the guide groove 45 before the detent apparatus 29 between carrier 12 and protective hood 15 can come into effect.

When the stop 21' is removed from the protective hood 15 and replaced e.g. by the stop 21 according to Fig. 5, the detent apparatus 29 is effective once more since the counterstop 22 is no longer firmly connected to the stop 21, as is the case when the stop 21' is inserted into the protective hood 15.

Fig. 7 shows a further embodiment of a stop 21", which may be used instead of the stop 21 according to Fig. 5 in the depth-of-cut setting apparatus 20. The guide channel 34 and the guide element 35 situated therein once more have a T-shaped profile, wherein however a toothed rail 48 is formed on one of the mutually opposite channel walls in the transverse part 341 of the guide channel 34. Engaging in said toothed rail 48 is a toothed portion 49, which is provided on one of the mutually remote lateral surfaces of the transverse part 351 of the guide element 35'. The guide element 35' is divided along its axis into the element parts 351 and 352, and the element parts 351 and 352 are loaded by a spring in the form of compression spring 52 in such a way that they are spread apart from one another. Consequently, in the the toothed portion 49 on the element part 351 is pressed into the toothed rail 48 and the stop 21" is fixed in the guide channel 34.

Integrally formed on the element part 352 is a button 50, which is guided displaceably on a coaxial pin 51, which in turn is integrally formed on the element part 351. The compression spring 52 is supported against the button 50 and in the base of the pin 21 on the element part 351. The element part 352 carries the depth-of-cut indicator 41 and the element part 351 carries the stop limb 212 of the stop 21". For holding the stop 21" captive on the protective hood 15 the additional guide comprising guide groove 45 and locking lug 44 is again provided, wherein, in a reversal of the arrangement in the embodiment of the stop 21 in Fig. 5, the guide groove 45 is incorporated in the stop limb 212 and the locking lug 44 is realized on the protective hood as an arc-shaped rail extending concentrically with the guide channel 34.

As is shown in Fig. 3, a precise adjustment screw 53 may be provided for precise adjustment of the saw blade 11 relative to the depth scale 33 or for reliable displacement of the stop 21 and/or 21' and/or 21" in the range of tenths of a millimetre. This precise adjustment screw 53 is screw-fastenable in a finely threaded nut 54 fastened to the counterstop 22 and is supported by its free end against the stop limb 212 of the stop 21 and/or 21' and/or 21" so that, after fixing of the stop 21, 21', 21", the depth of cut of the saw blade 11 may be varied by rotating the precision adjustment screw 53 in the range of tenths of a millimetre.

As is evident from Fig. 3, an inspection window 55 affording a view of the saw cut produced by the saw blade 11 is incorporated in the lateral surface of the protective hood 15, close to the base plate 16 and the end face 151 of the protective hood 15. A further inspection window 56 may be provided in the opposite lateral surface of the protective hood 15 (Fig. 4).

The invention is not limited to the described plunge saw.

For example, the depth-of-cut setting apparatus 20 according to the invention may be used also on any hand tool machines with rotatable cutting disks, such as e.g. angle grinders with angle grinder disks.

Claims

Claims 1. Hand tool machine, in particular a hand-held circular saw,

having a cutting disk (11), in particular a circular saw blade, which is rotatable by means of an electric motor (13) and rotatably mounted on a carrier (12) having a handle (17) formed thereon, having a protective hood (15), which covers the cutting disk (11) and is rigidly connected to a base plate (16) having a through-slot for the cutting disk (11) and on which the carrier (12) is pivotally mounted, and having a setting apparatus (20) for limiting the depth of cut of the cutting disk (11) in a workpiece, which apparatus for preselecting a desired depth of cut comprises a stop (21i 21'; 21"), which is displaceable along a depth scale fixed spatially relative to the protective hood (15) concentrically with the pivot bearing arrangement between carrier (12) and protective hood (15) and is fixable in the desired setting position, and a counterstop (22), which interacts with said stop and is disposed in a fixed manner on the carrier (12), characterized in that the stop (21; 21'; 21") is connected to a guide element (35; 35'), which is situated displaceably in a guide channel (34) incorporated in the protective hood (15) and is clampable in the guide channel (34) by means of a fixing member (27) projecting from the protective hood (15), and that the depth scale (33) is mounted along the guide channel (34) directly on the protective hood (15).
2. Hand tool machine according to claim 1, characterized in that the guide channel (34) is disposed in the, in working direction, front end face of the protective hood (15) and the depth scale (33) is applied outside on a lateral surface of the protective hood (15).
3. Hand tool machine according to claim 1 or 2, characterized in that the guide channel (34) and the guide element (33) have a T-shaped profile and that the fixing member (27) comprises a threaded pin (37), which extends through the stop (21; 21'), is firmly connected to a turning handle (36), is screwable into a threaded bore (38) in the guide element (35) and is provided with a clamping shoulder (39) lying frontally against the stop (21; 21').
4. Hand tool machine according to claim 3, characterized in that the stop (21; 21') comprises a middle piece (211; 211'), which is supported against the end face of the protective hood (15) and has an axial bore (40) for passage of the threaded pin (37), a stop limb (212; 212'), which overlaps the lateral surface of the protective hood (15) and projects into the swivelling path of the counterstop (22), and a depth-of-cut indicator (41) projecting onto the other lateral surface of the protective hood (15) and that the clamping shoulder (40) lies against the end face of the middle piece (211; 211') remote from the protective hood (15).
5. Hand tool machine according to claim 4, characterized in that the length of the middle piece (211') is greater than the transverse dimensions of the middle piece (211') and that the stop limb (212') comprises a securing element (47) for positive engagement into the counterstop (22).
6. Hand tool machine according to claim 1 or 2, characterized in that the guide channel (34) and the guide element (35') situated therein have a Tshaped profile, that formed on at least one of the mutually opposite channel walls in the transverse part (341) of the guide channel (34) is a toothed rail (48), into which a toothed portion (49) formed on the guide element (35') engages, that the guide element (35') is divided in alignment into two element parts (351, 352) and the two element parts (351, 352) are loaded by a spring (52), which spreads them apart, and that the one element part (351) is firmly, preferably integrally, connected to the stop limb (212) and the other element part (352) is firmly, preferably integrally, connected to a button (50).
7. Hand tool machine according to claim 6, characterized in that the button (50) is guided in an axially displaceable manner on a pin (51) formed on the limb stop (212) and that the spring, which spreads the element parts (351, 352) of the guide element (35') apart, is formed by a compression spring (52), which is supported on the one hand against the button (50) and on the other hand against the base of the pin (51).
8. Hand tool machine according to one of claims 1 - 7, characterized in that provided between the protective hood (15) and the stop (21; 21' i 21") is an additional guide comprising a guide groove (45), which extends at a radial distance from the guide channel (34) and is closed at the end, and a locking lug (44), which engages into the guide groove (45), that the guide groove (45) is disposed in a lateral surface of the protective hood (15) and the locking lug (44) is disposed on the stop (21; 21') or vice versa and that the guide groove (45) is provided with an open-ended inlet (46) extending at right angles thereto.
9. Hand tool machine according to one of claims 1 - 8, characterized in that provided on the counterstop (22) is a precision adjustment screw (53) , which is screw fastenable in the counterstop (22) and supported by its free screw end against the stop (21).
10. Hand tool machine according to one of claims 1 - 9, characterized in that disposed on the depth scale (33) is a symbol (42) for a cutting disk exchange position, which defines a relative position between protective hood (15) and carrier (12) that is preferred for the cutting disk exchange.

A hand tool machine substantially as herein described with reference to the accompanying drawings.