EP3902655B1 - Hand-held power tool - Google Patents

Description

The present invention relates to a hand-held power tool, in particular a grinder, for simultaneously driving several grinding plates, preferably for simultaneously driving three grinding plates, in particular tiltable, rotating and/or oscillating and/or randomly circularly drivable grinding plates.

State of the art

Such hand tool tools are, for example, from EP 1 466 698 A1 known, which forms the basis for the preamble of claim 1. Furthermore, the EP 3 330 044 A1 referred.

Disclosure of the invention

The invention relates to a hand-held power tool with the features of claim 1. Advantageous refinements, variants and further developments of the invention can be found in the subclaims.

The invention is based on a hand-held power tool, in particular a grinder, for simultaneously driving several grinding plates, preferably for simultaneously driving three, in particular tilting, rotating and/or oscillating and/or randomly circularly drivable or driven grinding plates. The hand-held power tool has a motor with a drive shaft that specifies a motor axis, a central wheel driven by this motor, in particular a spur gear that specifies a central wheel axle, and several, in particular three, output shafts driven by the central wheel, each of which specifies an output shaft axis, each output shaft being used to drive one Grinding plate or at least one grinding plate holder is provided.

It is proposed that the motor axis is arranged eccentrically, in particular parallel and eccentrically, to the central wheel axis. It is arranged between a front output shaft axle and the central wheel axle. It is proposed that the motor axle intersects a connecting line between an output shaft axle, in particular on the front side, and the central wheel axle; i.e. is arranged between the output shaft axle, in particular on the front side, and the central wheel axle. This shifts weight to the front or front sanding plate, which means that the hand-held power tool runs more smoothly when sanding.

The central wheel axle and the input and output shaft axles are preferably arranged essentially parallel to one another. The central wheel axle is preferably arranged in the center of a regular polygon, in particular a regular triangle, in the corners of which the three output shaft axes in particular are arranged.

Furthermore, it is proposed that the motor or its motor axis, relative to the central wheel axis, is arranged opposite a handle or handle housing, in particular a bar handle, which is aligned transversely to the central wheel axis. As a result, the motor acts as a counterweight to the handle, in particular to the accumulator arranged in or on the handle. This means that the three grinding plates in particular are loaded as evenly or homogeneously as possible. Fatigue-free work, increased smoothness and/or a better balanced hand tool are provided. This means that user-friendliness can be increased.

Because the handle housing protrudes from the main housing in the form of a bar handle, it can be easily and/or comfortably grasped by one hand. The hand-held power tool can be easily guided, especially into corners or under objects that limit the accessibility of workpieces to be machined. The visibility of the hand-held power tool or the workpiece to be machined is improved because the user's hand is less in the field of vision of the workpiece to be machined. The user-friendliness is increased.

It is proposed that the handle or the handle housing is intended to accommodate a battery, in particular a replaceable battery, preferably a replaceable plug-in battery. Because the accumulator is at least essentially arranged in the handle, the main housing can be designed to be compact. Accessibility for charging and/or replacing the battery can be improved. The motor, which is arranged eccentrically in relation to the central wheel axis opposite the handle, represents a counterweight to the accumulator. The hand-held power tool is better balanced due to the opposite arrangement of the motor and accumulator. The centers of gravity of the motor and accumulator are not on one side of the center axis or the hand tool.

It is proposed that the handle or the handle housing protrude from a main housing, which accommodates at least the motor, the central wheel and the input and output shafts, at an angle between 45°-135° from the main housing, based on the orientation of the central wheel axle.

Such an orientation allows the handle to be gripped comfortably. The fingers can wrap around the handle. The guidance of the hand-held power tool is made easier and the visibility, in particular of a front of the hand-held power tool, is improved.

It is proposed that a longitudinal axis of the handle, or essentially a center axis of the handle, and the central wheel axis span a plane, with two output shafts being arranged mirror-symmetrically to the plane. Thus, two of the grinding plates or grinding plate holders are arranged essentially mirror-symmetrically to the plane. This means that the weight and load distribution of the hand tool is ideal. The grinding result is as homogeneous as possible. The usability is balanced. The hand tool fits well in the hand. The rear output shaft axes are symmetrical to the center axis of the accumulator or the handle. The center axis of the battery, motor and front output shaft or front sanding plate lie on the plane or the middle plane of the hand tool. This means that the left and right hand tool sides are balanced, which reduces the forces on the user's hand-arm system when working.

It is suggested that the front output shaft comes to rest in the plane. In particular, the third output shaft comes to rest relative to the central wheel axle opposite the handle. This defines a front side of the device opposite the handle. The weight of the hand tool is as balanced as possible.

It is suggested that the motor axis comes to rest in the plane. The motor and/or the motor axle is arranged essentially between the third output shaft and the central wheel axle, in particular in the plane.

It is suggested that the plane intersects the accumulator and/or the motor in the middle. If possible, mirror symmetry of the hand-held power tool is made possible between the right and left sides of the plane. As a result, as little as possible moment is generated around the center axis of the handle, which ensures fatigue-free work and comfortable handling of the hand-held power tool.

It is proposed that the center of gravity of the hand tool comes to lie relative to the central wheel axle relative to the motor axle or the motor and / or comes to lie between the handle and the central wheel axle. In particular, the center of gravity comes to rest on the plane. This also means that as far as possible no moment is generated around the center axis of the handle, which ensures fatigue-free work and comfortable handling of the hand-held power tool. Furthermore, this or the position of the accumulator makes it possible for the hand-held power tool to stand securely on the edge of the rear sanding plate and the end of the handle. This means that the sanding discs are in the air and can cool down better during work breaks and be freed from dust. Two stable positions for the sander can sometimes be provided - firstly, standing on all three sanding plates; secondly, store it on the edge of the two rear sanding pads and the free end of the handle.

It is proposed that the hand tool is provided for three-point mounting on two grinding plates facing the handle and the free end of the handle or the free end of the plug-in accumulator.

This allows the sanding discs to cool down quickly. It is easy to check the condition of the abrasive. It is easy to check the condition of the area of the hand-held power tool facing the workpiece to be machined. It is also easy to grip the handheld power tool or the handle again due to the good accessibility.

The invention is based on a hand-held power tool, in particular a grinder, for the simultaneous drive of several, preferably for the simultaneous drive of three, in particular tiltable, rotating and/or oscillating and/or randomly circularly drivable or driven grinding plates, having a main housing which has at least one Motor for driving the sanding disc. It is proposed that a handle housing that forms a handle projects essentially transversely to the main housing, in particular protrudes like a rod handle from the main housing, in particular wherein the handle housing is intended to accommodate an accumulator, in particular a plug-in accumulator. The main housing typically accommodates a motor with a drive shaft that specifies a motor axis, a central wheel driven by this motor, in particular a spur gear that specifies a central wheel axle, and several, in particular three, output shafts driven by the central wheel, each of which specifies an output shaft axis, each output shaft being used to drive one Grinding plate or at least one grinding plate holder is provided. Typically, the central wheel axle and the input and output shaft axes are preferably arranged essentially parallel to one another. The central wheel axle is preferably arranged in the center of a regular polygon, in particular a regular triangle, in the corners of which the three output shaft axes in particular are arranged.

Because the handle housing protrudes from the main housing in the form of a bar handle, it can be easily and/or comfortably grasped by one hand. The hand-held power tool can be easily guided, especially into corners or under objects that limit the accessibility of workpieces to be machined. The visibility of the hand-held machine tool or the workpiece to be machined is improved because the user's hand is not in the way. The user-friendliness is increased.

Because the accumulator is arranged at least essentially in the handle and not in the main housing, the main housing can be designed to be compact. Accessibility for charging and/or replacing the battery can be improved.

Furthermore, a status display for the state of the accumulator and/or the hand-held power tool is claimed, which switches on or is activated when the position of the hand-held power tool changes, in particular a movement of the hand-held power tool at least around the center of gravity of the accumulator or the hand-held power tool. It is also claimed that the status display switches off or is deactivated when the hand-held power tool is activated and/or after a predetermined or predeterminable time interval.

drawings

Fig. 1

die Handwerkzeugmaschine in einer Frontansicht;

Fig. 2

die Handwerkzeugmaschine in einer Schnittdarstellung A-A;

Fig. 3

die Handwerkzeugmaschine in einer Schnittdarstellung B-B;

Fig. 4

die Handwerkzeugmaschine in einer Seitenansicht in einer Ruheposition;

Fig. 5

die Handwerkzeugmaschine in einer Seitenansicht;

Fig. 6

die Handwerkzeugmaschine in einer Rückansicht;

Fig. 7

die Staubabsaughaube in einer perspektivischen Ansicht;

Fig. 8

das System aus Handwerkzeugmaschine und Staubabsaughaube in einer Seitenansicht;

Fig. 9a-ddie

Handwerkzeugmaschine in einer schraffierten Darstellung in vier Ansichten;

Fig. 10

die Schnittfläche bzw. das Schnittflächenverhältnis eines eingeschnürten und eines ausgedehnten Bereichs der Handwerkzeugmaschine;

Fig. 11

die Handwerkzeugmaschine in einer perspektivischen Darstellung.

The invention is explained in more detail below using exemplary embodiments shown in the drawings. Show it:

Fig. 1

the hand-held machine tool in a front view;

Fig. 2

the hand tool in a sectional view AA;

Fig. 3

the hand-held machine tool in a sectional view BB;

Fig. 4

the hand-held power tool in a side view in a rest position;

Fig. 5

the hand-held power tool in a side view;

Fig. 6

the hand-held power tool in a rear view;

Fig. 7

the dust extraction hood in a perspective view;

Fig. 8

The system consisting of hand tool and dust extraction hood in a side view;

Fig. 9a-ddie

Hand tool tool in a hatched representation in four views;

Fig. 10

the cutting area or the cutting area ratio of a constricted and an expanded area of the hand-held power tool;

Fig. 11

the hand-held machine tool in a perspective view.

Fig. 1 shows the hand-held power tool in the form of a grinder 10 in a front view. The grinder 10 is intended to drive three grinding plates 12, 14, 16 at the same time. A front sanding plate 12 and two rear sanding plates 14, 16. Through a cardan-like or cardanic suspension (cf. Fig. 2 ) of the grinding plates 12, 14, 16, these are pivotally or tiltably mounted. They are driven in rotation and are well suited for sanding even curved surfaces. The grinder 10 can be activated via an actuation switch 18. A labeling element 20 advantageously assigns this device to a device series or a manufacturer.

Fig. 2 shows the hand-held power tool in the form of the grinder 10 in a sectional view AA through plane A (cf. Fig. 1 ). The front-side grinding plate 12 is arranged in front of a central wheel axle 22. It is arranged relative to a central wheel axle 22 opposite a handle 24. The two rear grinding plates 14, 16, of which only the grinding plate 16 can be seen in this illustration, are arranged on a side of the central wheel axle 22 facing the handle 24. The three grinding plates 12, 14, 16 are designed to be identical and interchangeable. A motor 26 has a drive shaft 28. The motor 26 or its drive shaft 28 specifies a motor shaft axis 30. The motor 26 drives a central wheel 34 via a pinion 32, which specifies the central wheel axle 22. The central wheel 34 is driven by the pinion 32 via a spur gear 36. The central wheel 34 has teeth 38 with which it drives three output shafts 40, of which only the front one can be seen in section AA. These output shafts 40 give again output shaft axes 42. Each output shaft 40 is in turn provided for at least indirectly driving one grinding plate 12, 14, 16. The central wheel 34 drives three spur gears 44 via the toothing 38 (of which the spur gear 44 driving the grinding plate 12 can be seen in section and the spur gear 44 driving the grinding plate 16 can be seen in the side view). The front spur gear 44 drives the output shaft 40; The drive mechanism is to be transferred analogously to all spur gears 44 driving the grinding plates 12, 14, 16. The output shaft 40 is here, for example, mounted in a housing part 60 via at least one deep groove ball bearing 46. A plain bearing 48 additionally supports the output shaft 40 in a further housing part 62. The two housing parts 60, 62 form an output shaft housing 202. The output shaft housing 202, together with a motor housing 200, which essentially encloses the motor 26, forms a main housing 64, which at least contains the motor 26, the central wheel 34 and the input and output shafts 28, 40 takes in. The output shaft 40 engages via a driver 50 in the coupling means 52 of the sanding plate 12. The sanding plate 12 can be clipped into a sanding plate holder 56 using locking hooks 54. The grinding plate holder 56 is arranged in the area of an opening 100 of the housing part 60. The coupling means 52 of the grinding plate 12 or the locking hooks 54 can be inserted into the grinding plate holder 56 or onto the driver 50 through the opening 100. In addition to the low-friction rotational bearing of the grinding plate 12 (here with deep groove ball bearing 58), the grinding plate holder 56 also enables pivoting (here by a spherical plain bearing in a spherical holder in the housing part 60). The gear shaft-like drive enables the grinding plate 12 to be tilted relative to the housing part 60 or relative to the grinder 10. The central wheel 34 drives the grinding plates 12, 14, 16 in a forced rotating manner. In principle, an oscillating drive or a randomly circular drive of the grinding plates 12 is also possible, for example by means of output shafts 40 which are eccentrically accommodated in the spur gear 44 and which drive the grinding plates 12, 14, 16 in a forcibly coupled or randomly rotating manner, or an eccentric which is caused by the restriction of degrees of freedom of the Grinding plate and / or the output shaft generates an oscillatory movement - or the like (not shown in detail here).

The drive shaft 28 or the motor shaft axis 30 is arranged eccentrically to the central wheel 34 or to the central wheel axle 22. It is between the front Output shaft axle 42 and the central wheel axle 22 are arranged. Both axes 22, 30 are cut through plane A or come to rest in it. The motor 26 is displaced in the direction of the front sanding plate 12 or its sanding plate holder 56. The motor 26 or its motor shaft axis 30 is arranged relative to the central wheel axis 22 opposite the handle 24. The handle 24 is also cut in the middle by plane A, ideally divided in mirror symmetry. The motor shaft axis 30, the central wheel axis 22 and the output shaft axes 42 are aligned parallel to one another. The handle axis 66 or the center axis 86 or longitudinal axis 84 of the particularly rod-shaped handle 24 is arranged transversely to the central wheel axis 22. The angle α is around 45-135°, in the present exemplary embodiment around 100°. The handle 24 protrudes from the main housing 64. The plane A or the cutting plane AA is, so to speak, also spanned by the handle axis 66 and the central wheel axis 22. The handle 24 is rod-shaped, essentially round or oval or the like. It is formed by the handle housing 68, which can be formed at least partially in one piece with the main housing 64. The handle 24 is intended to hold an accumulator 70. This can be permanently integrated or designed as a replaceable accumulator 70. In the present exemplary embodiment it is designed as a replaceable plug-in accumulator 72. It is inserted into the free end 74 of the handle 24 and is releasably connected to the handle housing 68 via locking elements (not shown here). Optionally, a speed of the motor 26 can be adjusted using an adjusting wheel 76. Furthermore, the handle 24 and the main housing 64 are ergonomically shaped. The concave notch 78 in the transition from the handle 24 to the main housing 64 is used for intuitive gripping with the index finger. This area can also be covered with a Softgripp 80. Of course, other areas of the hand-held power tool can also be covered with specially haptic and/or tactile materials. But the top side 82 of the main housing 64 is also intended to support a hand, in particular the palm of the hand, be it to guide the hand-held power tool with two hands or with one hand, simply by gripping around the main housing 64.

Fig. 3 shows the grinder Fig. 1 in a sectional view BB in plane (B). The drive shaft 28 drives the central wheel 34 via the pinion 32. The motor shaft axis 30 and thus the motor 26 is arranged eccentrically to the central wheel 34. Namely shifted towards a front side 90 of the grinder 10. The central wheel axle 22, the motor shaft axle 30 and the output shaft axle 42 of the front output shaft come to rest in plane A. Plane B is spanned orthogonally to this plane A. The output shafts 40, which are arranged mirror-symmetrically to plane A, come to rest in plane B. The central wheel axle 22 is arranged in the center of a regular triangle 92, in the corners of which the three drive shaft axes 42 are arranged. The three spur gears 44 are driven to rotate via the central wheel 34. The spur gears 44 in turn drive the output shafts 40, which at least indirectly drive the grinding plates 12, 14, 16 or grinding plate holders 56 (cf. Fig. 2 ). Furthermore, parts of the main housing 64 or the housing part 60 and the further housing part 62 are shown, which hold the input and output elements of the grinder 10 in position.

Fig. 4 shows the grinder 10 in a rest position on a support surface 94, for example a workpiece to be machined. The grinder 10 rests on three points, namely on a free end 96 of the insertable accumulator 70 (alternatively, it could also rest on the free end 74 of the handle 24, in particular with an accumulator 70 firmly installed in the handle 24) and on the edge 98 the rear sanding plates 14, 16, in particular the two edge 98 of the sanding plates 14, 16 facing the free end 74, 96 of the handle 24 or insert accumulator 72 (whereby only the sanding plate 14 is visible since it covers the sanding plate 16). In principle, the same reference numbers are assigned to the same components from the different figures, but they are not necessarily explained again for each figure.

Fig. 5 shows the hand tool or a grinder 10 in a side view. The housing part 60 has three grinding plate receiving areas 102, of which in the Fig. 5 only two can be seen. The area of the housing part 60 that supports the sanding plate holder 56 and its components such as bearings is defined as the sanding plate receiving area 102. By way of example, this is the area with the enveloping circle diameter 104 around the grinding plate receiving areas 102. In the present exemplary embodiment, this area is in particular the immediately surrounding housing area 106 of the housing part 60, in Offset in the direction of the grinding plane 112 (to accommodate the bearings, better accessibility and/or to improve the freedom of movement of the grinding plates 12, 14, 16, for example when tilting/pivoting). In other words, the surrounding housing area(s) 106 is set back from the sanding pad receiving area(s) 102. However, this setback is not to be understood as a depression 108 in the sense of the invention. The sanding plate receiving areas 102 each have openings 100 through which the removable sanding plates 12, 14, 16 can be connected to the sander 10. The coupling means 52 and/or locking hooks 54 can thus be connected to the output shafts 40 and/or grinding plate holders 56 (see sectional view Fig. 2 ). Alternatively, the grinding plate holders 56 or the output shafts 40 can also protrude through the grinding plate holder areas 102. If only output shafts 40 protrude through the housing part, be it because the grinding plates 12, 14, 16 are received outside the housing part 60 of the hand-held power tool, or because the grinding plates 12, 14, 16 are inextricably connected to the output shafts 40, under the Sanding plate receiving area 102 can only be understood as the area that represents the opening 100; or the area that stores the output shafts 40 in the housing part 60 of the hand-held power tool.

The housing part 60 has an air duct 120 between two adjacent sanding plate receiving areas 102 or the openings 100 (in the gap 122, so to speak). This is formed by a depression 108. In the area of the air duct 120 or the recess 108, the distance 110 between the housing part 60 and a grinding plane 112 is increased, in particular increased compared to the distance 111 of the housing area 106 to the grinding plane 112. The recess 108 is therefore set back relative to the housing area 106. The recess 108 has a concave shape 118. It tapers towards the center of the housing part 60 or becomes narrower in the circumferential direction. In addition, an extent of deepening decreases in this direction. The housing part 60 is therefore retracted or notched in the direction facing away from the grinding plane 112. Starting from a center area 114 of the housing part 60, in particular a center area 114 in the center between the grinding plates 12, 14, 16 or in the area of the central wheel axle 22 intersecting the housing part 60, the distance 110 increases between the housing part 60 and grinding plane 112 along the air duct, or the recess 108, in the radial direction outwards, i.e. in the direction of the edge 116 of the housing part 60. The depression 108 is therefore larger in the outer region of the housing part 60 than in a central region. The depression 108 serves for better air flow. The depression 108 forms at least part of an air duct 120, in particular for dust extraction.

Analogous to the recess 108 between the sanding plates 12, 16 (front and rear sanding plates) or the associated sanding plate receiving areas 102, a recess 108 is also provided between the rear sanding plates 14, 16 or the associated sanding plate receiving areas 102 (cf. Fig. 6 ). The Fig. 6 , which shows this depression in the rear view, it can also be seen that the depression or the distance 110 increases from the center region 114 of the housing part 60 to the edge 116 of the housing part 60 or from the center radially outwards. The rear recess 108 is constructed mirror-symmetrically to plane A (see also section AA according to Fig. 2 ). The recess 108 also enables a contact-free tilting 124 of the sanding plates 12, 14, 16 relative to the housing part 60. This means that, for example, when the sander 10 is in operation, one edge of the sanding plate 12, 14, 16 does not rub against the housing part 60. The three recesses 108 between the sanding plates 12, 14, 16 and the grinding plate holders 56 are each arranged offset from one another by 120° starting from the center. They are each mirror-symmetrical to the bisectors of the uniform triangle.

Fig. 5 and 6 also show a housing separating edge 126. The housing separating edge 126 is arranged between the housing part 60 and the further housing part 62. Both housing parts 60, 62 are part of the output shaft housing 202 or the main housing 64. The housing separating edge 126 represents in particular a housing separating joint 130. The housing separating edge 126 or the housing separating joint 130 is formed by assembled housing shells of the hand-held power tool or the grinder 10. It forms a setback in the housing surface. It runs all the way around the output shaft housing 202. It provides a form-fitting element 132, in particular a locking groove 134, for receiving a corresponding form-fitting element 136 of a dust extraction hood 138 (cf. Fig. 7 ), preferably a locking extension 140 of a dust extraction hood 138 serves. The positive locking element 132 can be used instead of a groove or depression in principle also represent a protuberance or male form-fitting element. Likewise, a female form-fitting element can be provided on the dust extraction hood 138 instead of a male one. Furthermore, the recess 108 in the housing part 60 serves as a further form-fitting element 142, in particular as a stop element 144 for a further corresponding form-fitting element 146 on the dust extraction hood 138. When the dust extraction hood 138 is intended to be plugged on from the grinding plate level 112 onto the output shaft housing 202 or placed over the housing part 60 the form-fitting element(s) 146 as a stop or as a stopper. This means that the dust extraction hood 138 is not pushed too far onto the output shaft housing 202. As soon as the positive locking elements 146 strike, the positive locking elements 136 also snap into their intended position or into the corresponding positive locking elements 132.

Fig. 7 shows the dust extraction hood 138 in a perspective view. It is a removable dust extraction hood 138 for a hand-held power tool, in particular for the grinder 10, in particular wherein the hand-held power tool is designed to drive several, in particular tiltably mounted, rotating and/or oscillating and/or randomly circular grinding plates 12, 14, 16. The dust extraction hood 138 has a connector 148 for connection to a dust extraction device (not shown here) - typically a mobile or stationary vacuum cleaner or dust extraction device. The nozzle 148 projects outside 149 of the dust extraction hood 138. The dust extraction hood 138 has a suction opening 150 extending from the nozzle 148, which is open to the interior 152 of the dust extraction hood 138. The dust extraction hood 138 has a substantially triangular geometry, in particular a substantially regular triangular geometry. What is meant here by essentially is that the corners 154 of the “triangle” are as in Fig. 7 shown can be rounded. In addition, the legs 156 can also deviate from a straight shape to some extent, for example be slightly curved or the like.

In the area of the suction opening 150, the dust extraction hood 138 has an extension 158. This serves to avoid cross air flow, especially from below 184 (cf. Fig. 8 ) of the extension 158, i.e. below the suction opening 150 facing away from the side of the extension 158. The extension 158 projects into the interior 152 of the dust extraction hood 138. The extension 158 has, starting from the suction opening 150, a main extension direction 160 into the interior 152 of the dust extraction hood 138. Furthermore, the extension 158 has at least one, in particular two, walls 162. This serves to reduce the cross air flow, in particular to reduce the cross current from below 184 of the dust extraction hood 138 and/or from the side 164 within the dust extraction hood 138. The extension 158 and/or the wall 162 can also be at least partially open to the side 166, 168, in particular to Enabling cross-air flow in at least this area 170, 172. The extension 158 forms part of an air duct 159. In particular, the part of the air duct 120 and the other part of the air duct 159 together form an air duct 120, 159.

The dust extraction hood 138, or the frame 174 of the dust extraction hood 138, is flexible, in particular transversely to the bottom or top of the dust extraction hood 138 or in the direction of the interior 152 or the exterior 149 of the dust extraction hood 138. This enables resilient pretensioning and/or pressing the dust extraction hood 138 to the hand-held power tool, in particular the grinder 10, or its housing. This allows a tool-free and/or secure and/or low-gap connection to the grinder 10 to be established.

The frame 174 or the dust extraction hood 138 tapers from bottom to top. In the area of the form-fitting elements 136, for connection to the form-fitting elements 142 of the hand-held power tool, the frame 174 or the dust extraction hood 138 is tapered. This ensures that an upper edge 186 of the frame 174 or the dust extraction hood 138 can rest on the housing of the hand-held power tool with as little gap as possible. The pretensioning force of the dust extraction hood 138 in this area can be particularly efficient.

Furthermore, the dust extraction hood 138 can be designed as a spacer and/or impact protection for the hand-held power tool or the grinder (see also Fig. 8 ). Instead of the housing of the grinder 10, the frame 174 or the rounded corners 154 and/or legs 156 serve as impact protection.

The dust extraction hood 138 also has a handle contour 176. The handle contour 176 represents a slight elevation on the leg 156 or the frame 174. The friction between the finger and the dust extraction hood 138 when pressing or pulling the dust extraction hood 138 onto or from the grinder 10 is thereby improved. In addition, the handle contour 176 resembles the silhouette contour 178 of at least one area of the hand-held power tool or the grinder (cf. Fig. 5 and 6 ). The silhouette contour is formed by the contour of the edge 116 of the housing part 60, in particular in the area of the recess 108, especially when the edge 116 or the grinder 10 is viewed from the side.

Fig. 8 represents the system consisting of a hand-held power tool or grinder 10 with a connected or attached dust extraction hood 138. In addition to the components already described, the dust extraction hood 138 or the hand-held power tool or the grinder 10 preferably has a particularly elastic connecting element 179, in particular an elastic band 180 rubber-elastic band 180 for connecting the nozzle 148 or a nozzle adapter 182 and the grinder 10. The elastic band 180 is tensioned, in particular between a free end 74, 96 of the handle 24 or accumulator 70, 72 of the grinder 10 and the socket 148 or socket adapter 182. The elastic band is preferably captively fastened to the nozzle 148, the nozzle adapter 182 or the handle 24. Here, for example, by gluing or spraying it onto the nozzle adapter. Alternatively, the band can also be detachable on one side, so that in the open state it can be attached to or around the other component and can be fixed again - for example with a push button, a locking mechanism or the like.

Fig. 9 Figure ad shows the hand tool or the grinder 10 of the previous figures in a shaded representation to make curvatures visible. Figure 9a shows the grinder 10 in a side view, Figure 9b in a rear view, Figure 9c perspective view and Figure 9d in a top view. The grinder 10 is for the simultaneous drive of three, in particular tiltable, rotating and / or oscillating and / or randomly circularly driven grinding plates 12, 14, 16, having at least one output shaft housing 202, which essentially has three output shafts 40 (here not shown, cf. in particular Fig. 2 ) orthogonal to the output shaft axes 42, 202, 204, 206 and a motor housing 200 that essentially encloses the motor 26 orthogonally to the motor shaft axis 30. The grinder 10 has a handle 24. The front output shaft axis 42, 204 can be better distinguished from the rear output shaft axes 42, 206, 208 by the additional reference numbers. The output shaft housing 202 encloses the three output shafts 40 at least substantially orthogonally to the output shaft axes 42. The motor housing 200 encloses the motor 26 at least substantially orthogonally to the motor shaft axis 30.

A sectional surface 210 of the motor housing 200 orthogonal to the motor shaft axis 30 in a constricted region 212 of the motor housing 200 is less than relative to a sectional surface 214 of the output shaft housing 202 orthogonal to the output shaft axes 42 in an extended area of the output shaft housing 202, in particular the most extensive area 216 of the output shaft housing 202 70%, in particular less than 65%, preferably less than 55%. In the one shown Fig. 10 it is around 52%. The extended area 216 is to be understood in particular as meaning the area with the largest sectional area 214 of the output shaft housing 202. Thus, in this area 216, an extension, for example the length 218 or the circumferential distance or length 215 around the output shaft housing 202, is maximum. Furthermore, in the side, rear and top views Figure 9a-c also a length and a width of the motor housing 200 in the constricted area 212 and of the output shaft housing 202 in the extended area 216 are provided with the following reference numerals: output shaft housing 202: length 218, width 220; Motor housing: length 222, width 224. In proportion, the extended area 216 of the output shaft housing 202 is around 30% longer and around 65% wider than the constricted area 212 of the motor housing 200. The sectional area ratio of the extended area 216 of the output shaft housing 202 compared to the constricted area 212 of the motor housing 200 is also around 190% (cf. Fig. 10 ).

Out of Fig. 10 The sectional area ratio of certain areas also emerges. The cutting surface 214 of the output shaft housing 202 in a rear area 226 of the hand-held power tool or the grinder 10 is too small than 75%, in particular less than 50%, preferably less than 25% of the cut surface 210 of the motor housing 200 projected along the motor shaft axis 30, in particular in the constricted area 212. Analogously, the grinding surface 232 of grinding plates 14, 16 applied to the rear of the grinder 10 is less than 75%, in particular less than 50%, preferably less than 25%, of the cut surface 210 of the motor housing 200 projected along the motor shaft axis 30, especially in the constricted one Area 212, covered. In a front area 228 of the hand-held power tool, the cut surface 210 of the motor housing 200 projected along the motor shaft axis 30, in particular also in the constricted area 212, covers the cut surface 214 of the output shaft housing 202 to more than 70%, in particular to more than 90%, preferably completely. Analogously, the grinding surface 234 is covered by a grinding plate 12 applied to the front of the grinder 10 to more than 70%, in particular to more than 90%, preferably completely, of the cut surface 210 of the motor housing 200 projected along the motor shaft axis 30, in particular also in the constricted area 212 .

Further goes out Fig. 10 also a circumferential length 211 of the motor housing 200 orthogonal to the motor shaft axis 30 or the output shaft axes 42 in a particularly constricted area 212 of the motor housing 200 relative to a circumferential length 215 of the output shaft housing 202 orthogonal to the output shaft axes 42, 204, 206, 208 in a particularly extended area 216 of the Output shaft housing 202. It is less than 80%, here around 70%. In other words, the circumferential length 215 of the output shaft housing 202 is around 145% compared to the circumferential length 211 of the motor housing 200 in the constricted area 212.

Furthermore, one, in particular two, of the three output shaft axes 42, in particular the two rear output shaft axes 206, 208 of the hand-held power tool, lie outside the motor housing 200, in particular outside the constricted area 212 of the motor housing 200. These output shaft axes 206, 208 therefore at least do not intersect the motor housing 200 in the constricted area 212, especially nowhere. Furthermore, in particular one, preferably two, of the three output shaft axes 204, 206, 208 lie in particular the two rear output shaft axes 206, 208 of the hand-held power tool or the grinder 10, outside the handle 24, in particular the rod-shaped handle 24. They also lie outside a dented area 230 or a concave indentation of the handle 24 and / or motor housing 200 or a dented transition area 276 of the handle 24 and motor housing 200 The front output shaft axis 204 of the hand-held power tool or the grinder 10 lies within the motor housing 200 and/or within a motor housing handle 236 - i.e. cuts this.

From the side view according to Fig. 9a It can also be seen that the ratio of the height 238, 240 of the hand-held power tool in the direction of the output shaft axes 42, 204, 206, 208, in particular a height 238 of a motor and output shaft housing 200, 202, to the length 242 of a substantially rod-shaped handle 24, in particular a length 242 of a rod-shaped handle 24 which projects substantially orthogonally to the motor housing 200 or the input and output shaft axis 30, 204, deviates by less than 50%, in particular deviates by less than 75%, preferably deviates by less than 85%, in particular in is approximately identical. Under a rod-shaped handle projecting essentially orthogonally to the input and output shaft axis 30, 204, the aim here is to be in an angular range of 60°-120°, in particular 75°-105°, preferably 90° with respect to the input and output shaft axis ( n) 30, 204, 206, 208 can be understood. This can advantageously provide a very compact hand-held power tool. The center of gravity S thus moves as close as possible to the grinding plates 12, 14, 16. Furthermore, a ratio of a total length 244 of the hand-held power tool is orthogonal to at least one input or output shaft axis 30, 42, 204, 206, 208, in particular from one end of the motor housing 200 up to one end of the rod-shaped handle 24, relative to a height 238, 240 of the hand-held power tool along at least one direction of the input or output shaft axis 30, 42, 204, 206, 208, in particular from a grinding plate level 112 to the end of the handle 24 or Motor housing 200, is larger than 10%, in particular larger than 25%, preferably around 40% larger.

Furthermore, the weight of the accumulator 72 is relative to the components of the drive train, in particular including the motor 26, the pinion 32, the central gear 34, the output shafts 40 and spur gears 44, around 10-50% more, in particular 30-40% more. This can positively influence the position of the center of gravity S. A volume of the motor and output shaft housing 200, 202 compared to the rod-shaped handle housing 68 is around 20-70% more, in particular around 50% more.

From the side view and the perspective view Fig. 9a , d , as well as the Fig. 11 , further shows a grinding machine housing 250 with at least one housing shell element 252 and with at least one further housing shell element 254 connected to the housing shell element 252, which at least partially form a handle 24, 258. The grinding machine housing 250 is characterized by at least one ventilation opening 262, in particular a ventilation slot, formed at least in sections in the area of a separating edge 260 of the housing shell element 252 and the further housing shell element 254. The ventilation opening 262 advantageously extends over two areas 264, 266, which are at an angle 268, in particular an angle 268 (cf. Fig. 10 , side view) are arranged between 90° and 120°, preferably between 100° and 105° to one another. The angle is advantageously based on the alignment of the rod-shaped handle to the motor housing. The ventilation opening areas are advantageously aligned parallel to their main extension. The ventilation opening 262, in particular that of the section 266 in the area of the handle 258, is advantageously intended to flow around the hand of a user, in particular to cool, warm and/or dry.

The housing shell element 252 and the further housing shell element 254 are connected to one another, in particular fixed to one another, in particular along an at least substantially entire contact line and/or surface of the housing shell element 252 and the further housing shell element 254, at least essentially free of visible fastening elements. Furthermore, the handle 24, 258 is designed to be at least substantially free of separating edges, at least on one side of the handle 24, 258 that faces and/or faces away from a grinding plate 12, 14, 16 or the tool side.

Furthermore, the grinding machine housing 250 has a motor housing section 270 and a rod-shaped handle housing section 272, the grinding machine housing 250 having a concave indentation 278 or a dent in a transition region 276 between the rod-shaped handle housing section 272 and the motor housing section 270 (cf. Fig. 10 ). This serves as an ergonomic contact surface for a finger, in particular a thumb of the user. The dent is particularly noticeable in the side view Fig. 9a clearly visible. The shading indicates the curved areas. Preferably, the ventilation opening(s) 262 can be formed by an offset of a housing edge of the housing shell element 252 and the further housing shell element 254.

Claims (14)

1. Hand-held power tool, in particular grinder (10), for simultaneously driving a plurality of grinding disks (12, 14, 16), preferably for simultaneously driving three grinding disks, which are in particular tiltable and/or are driven in a rotating and/or oscillating and/or randomly circular manner, comprising a main housing (64), which accommodates at least a motor (26) for driving the grinding disks (12, 14, 16), having a handle housing (68), which forms a handle (24) and protrudes substantially transversely to the main housing (64), wherein the motor (26) has a drive shaft (28) which defines a motor axis (30), furthermore a central wheel (34), which is driven by this motor (26) and which defines a central wheel axis (22); and a plurality of, in particular three, output shafts (40), which are driven by the central wheel (34) and which respectively define an output shaft axis (42), wherein each output shaft (40) is provided to drive, respectively, a grinding disk (12, 14, 16) or at least, respectively, a grinding disk holder (56), characterized in that the motor axis (30) is arranged eccentrically to the central wheel axis (22) between a frontal output shaft axis (40) and the central wheel axis (22).
2. Hand-held power tool at least according to Claim 1, characterized in that the motor (26) or its motor axis (30), in relation to the central wheel axis (22), is disposed opposite a handle (24) or handle housing (68), in particular a barrel handle, oriented transversely to the central wheel axis (22), or in that the handle housing (68), which forms a handle (24), in particular protrudes in the style of a barrel handle from the main housing (64) .
3. Hand-held power tool at least according to Claim 2, characterized in that the handle (24) or the handle housing (68) is provided to accommodate a storage battery (70), in particular an exchangeable storage battery (70), preferably an exchangeable insertable storage battery (72) .
4. Hand-held power tool at least according to Claim 2 or 3, characterized in that the handle (24) or the handle housing (68) protrudes from a main housing (64), which accommodates at least the motor (26), the central wheel (34) and the drive and output shafts (28, 40), at an angle (α) of 45°-135°, preferably 85°-105°, in particular in relation to the orientation of the central wheel axis (22) .
5. Hand-held power tool at least according to one of Claims 2-4, characterized in that a longitudinal axis (84), in particular the center axis (86), of the handle (24), and the central wheel axis (86), span one plane (A), wherein two output shafts (40) are arranged in mirror symmetry to the plane (A).
6. Hand-held power tool at least according to Claim 5, characterized in that the frontal output shaft (40) comes to lie in the plane (A).
7. Hand-held power tool at least according to one of Claims 5 or 6, characterized in that the motor axis (30) comes to lie in the plane (A).
8. Hand-held power tool at least according to one of Claims 5-7, characterized in that the plane (A) centrally intersects the storage battery (70) and/or the motor (26) .
9. Hand-held power tool at least according to one of the preceding claims, characterized in that the center of gravity (S) of the hand-held power tool, in relation to the central wheel axis (22), comes to lie opposite the motor axis (30), in particular in the plane (A), particularly preferably in a region (88) which extends from a connecting plane of the output shafts (40) lying in mirror symmetry to the plane (A) to the free end (74) of the handle (24), at a distance apart equating to the radius (r) of a grinding disk (12, 14, 16).
10. Hand-held power tool at least according to one of the preceding claims, characterized in that the hand-held power tool is provided for three-point mounting on two grinding disks (14, 16) facing toward the handle (24), and on a free end (74, 96) of the handle (24) or of the insertable storage battery (72).
11. Hand-held power tool according to one of the preceding claims, characterized in that the relationship of the height (238, 240) of the hand-held power tool in the direction of the output shaft axes (42, 204, 206, 208), in particular a height (238) of a motor housing and output shaft housing (200, 202), to the length (242) of a substantially barrel-shaped handle (24), in particular a length (242) of a barrel-shaped handle (24) protruding substantially orthogonally to the motor housing (200) or to the drive and output shaft axis (30, 204), varies by less than 50%, in particular by less than 75%, preferably by less than 85%, in particular is roughly identical.
12. Hand-held power tool according to one of the preceding claims, characterized in that a relationship of a total length (244) of the hand-held power tool orthogonally to at least one drive or output shaft axis (30, 42, 204, 206, 208), in particular from one end of the motor housing (200) up to an end of the handle (24), which latter protrudes in the shape of a barrel, relative to a height (238, 240) of the hand-held power tool along at least one direction of the drive or output shaft axis (30, 42, 204, 206, 208), in particular from a grinding disk plane (112) up to the end of the handle (24) or motor housing (200), is greater than 10%, in particular is greater than 25%, preferably is around 40% greater.
13. Hand-held power tool according to one of the preceding claims, comprising a grinding machine housing (250), having at least a housing shell element (252) and having at least a further housing shell element (254) connected to the housing shell element (252), which, at least in some sections, form a handle (24, 258), characterized by at least one vent opening (262), in particular a ventilation slot, formed, at least in some sections, in the region of a separating edge (260) of the housing shell element (252) and of the further housing shell element (254), in particular wherein the ventilation opening (262) extends over two regions (264, 268), which are arranged at an angle (268), in particular an angle (268), between 90° and 120°, preferably between 100° and 105°, one to another.
14. Hand-held power tool according to one of the previous claims, comprising a grinding machine housing (250) which has a motor housing portion (270) and a barrel-shaped handle housing portion (272), wherein the grinding machine housing (250), in a transition region (276) between the barrel-shaped handle housing portion (272) and the motor housing portion (270), has a concave indentation (278), in particular such that this serves as an ergonomic bearing surface for a finger, in particular a thumb, of the user.

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