HAND TOOL MACHINE

Description

[0001] The invention relates to a hand-held power tool, in particular a grinding machine and / or polishing machine, according to the preamble of claim 1.

[0002] Such a hand-held power tool is described, for example, in DE 10 2010 012 025. The operator can manually switch the machine between the forced rotation eccentric mode and a freewheel eccentric mode. In the forced rotation eccentric mode, the tool shaft performs defined rotary movements by a planetary gear connected to the tool shaft rolling against a ring gear supported on the machine housing. When the ring gear is disengaged from the planetary gear, the tool shaft can rotate relatively freely and is driven by at least one tool shaft bearing.

[0003] However, switching between operating modes is complex.

[0004] It is therefore the object of the present invention to provide an improved operating concept for a hand-held machine tool, in particular a grinding machine or polishing machine.

[0005] To solve the problem, a hand-held machine tool according to the technical teaching of claim 1 is provided.

[0006] In the second direction of rotation, it is possible for the rolling element supported on the tool shaft to drive the rolling element supported on the machine housing along with it in rotation. However, it is also possible for the rolling element associated with the tool shaft to be rotatable in the second direction of rotation, so that it can be held stationary or essentially stationary by the rolling element supported on the machine housing and non-rotatable in the second direction of rotation.

[0007] The basic idea is that the forced rotation eccentric mode can be switched on or off by reversing the direction of rotation of the tool shaft. The forced rotation eccentric mode is therefore active in the first direction of rotation of the tool shaft, so that the forced rotation guide can, so to speak, force a specific rotation of the tool shaft relative to the machine housing. The freewheel device locks in this case. Thus, the rolling element can no longer rotate freely relative to the component to which it is supported by the freewheel device—i.e., the machine housing or the tool shaft.

[0008] However, when the tool shaft rotates in the second direction of rotation, the rolling element still supported in the first direction of rotation of the tool shaft or the locking direction of the freewheel device is released, meaning it can rotate freely and, for example, be carried along by the other rolling element or remain supported by the other rolling element. This means that the tool shaft may no longer be guided by the forced rotation guide, meaning it is no longer in forced rotation eccentric mode.

[0009] The forced rotation eccentric mode is therefore activated in the locking direction of the freewheel device and deactivated in the freewheeling direction of the freewheel device.

[0010] In the forced rotation eccentric mode, the tool shaft expediently performs a forced rotation around the drive axis using the forced rotation guide, changing its rotation angle position relative to the machine housing of the hand-held power tool.

[0011] In the forced rotation eccentric mode, it is expediently provided that the freewheel device is completely locked, i.e., the mobility of the locked rolling element relative to the component to which it is supported via the freewheel device is completely prevented. For example, a ring gear can no longer rotate relative to the machine housing in this case. However, it is also possible for the freewheel device to provide a lower supporting force in the locked position than if the rolling element were completely blocked, but rather a rotational inhibition. The rolling element is then not completely blocked relative to the supporting component, i.e., the machine housing or the tool shaft, but cannot rotate freely; instead, its rotation is inhibited.The supporting force can therefore be somewhat lower than the force required to completely block or impede a relative movement of the supported rolling element to the supporting component, the machine housing or the tool shaft.

[0012] When the forced rotation eccentric mode is deactivated, a free rotation eccentric mode is available, for example. For example, it is provided that the tool shaft is in a free rotation eccentric mode in the second direction of rotation. In this mode, the tool shaft rotates due to bearing friction of the at least one tool shaft bearing upon rotation of the drive shaft and is freely rotatable relative to the drive axis. It is understood that the mobility is still limited by a certain amount of bearing friction, but is to be understood as free mobility in the sense that the previously supporting rolling element can be carried along by the other rolling element.

[0013] The hand-held power tool expediently has braking means for braking the tool shaft or the disk tool mounted thereon. The braking means comprise, for example, a braking body, a sealing sleeve, or other braking means that act on the tool shaft or the tool, or both. The braking means are intended in particular for operation of the hand-held power tool with the forced rotation eccentric mode deactivated.

[0014] Preferably, one of the rolling elements is or comprises a ring gear and the other rolling element is or comprises a planetary gear. The planetary gear is housed in the ring gear and can roll against it. For example, the ring gear is assigned to the machine housing, while the planetary gear is assigned to the tool shaft. However, the reverse configuration is also possible, with a planetary gear being provided on the machine housing, around which the ring gear, in a manner of speaking, orbits. The ring gear, in turn, is attached to the tool shaft.

[0015] In principle, however, it is also conceivable that one of the rolling elements is designed as a sun gear, around which a rolling element designed as a planetary gear orbits, so to speak, or a planetary gear rolls.

[0016] It is preferred if the rolling elements have a toothing so that they engage with each other via their toothing. However, it is also possible for the rolling elements to move along each other frictionally due to a frictional engagement, i.e., one rolling element rolls or rolls against the other rolling element frictionally when the first direction of rotation is set and the freewheel device assumes the locking direction or locking position.

[0017] For example, it is possible for only one of the rolling elements to be supported relative to the tool shaft or the machine housing by means of a freewheel device. Therefore, only a single freewheel device can be provided, as is also shown in the drawing.

[0018] The handheld power tool can also have multiple freewheel devices. For example, it is possible for one freewheel device to be arranged between the rolling element assigned to the tool shaft and the tool shaft, while another freewheel device is arranged between the machine housing and the rolling element assigned to the machine housing. For example, it is possible for one of these freewheel devices to completely block the rotational movement of the rolling element arranged on it in the locked position, while the other freewheel device brakes the rolling element arranged on it in the locked position, i.e., inhibits its rotational movement or rotational mobility. The other freewheel device therefore does not completely block the rotational movement of the rolling element assigned to it.

[0019] It is possible for the rolling element, which can be supported in a rotationally fixed manner with respect to the machine housing or the tool shaft by means of the at least one freewheel device, to be rotatable with respect to the machine housing or the tool shaft by means of a rotary bearing, in particular a rolling bearing, particularly preferably a ball bearing, when the freewheel device assumes the freewheeling direction or the tool shaft rotates in the second direction of rotation.

[0020] It is preferred if the freewheel device is arranged on a bearing or forms a component of a bearing with which the rolling element is rotatably mounted relative to the machine housing or the tool shaft. For example, it is possible to use a bearing, in particular a rotary bearing, particularly preferably a ball bearing, that has an integral freewheel device.

[0021] It is preferred if the at least one tool shaft bearing comprises a first and a second tool shaft bearing, which are spaced apart from the drive axis or the longitudinal extension of the drive shaft. It is particularly preferred if the two tool shaft bearings are provided at the respective longitudinal end regions of the tool shaft and / or the respective longitudinal end regions of the drive shaft.

[0022] It is possible for the tool shaft to be a hollow shaft with the drive shaft located inside it. It is also possible for the drive shaft to be located inside the tool shaft or to engage with the tool shaft. For example, the tool shaft can be mounted eccentrically on the outside of the drive shaft.

[0023] A preferred variant is one in which the drive shaft has an interior space, for example, a hollow shaft, in which the tool shaft is arranged. According to the invention, the drive shaft has a hollow shaft on or is designed as a hollow shaft in which the tool shaft is arranged.

[0024] It is advantageous for the tool shaft to be mounted eccentrically in the drive shaft. The at least one tool shaft bearing is arranged, for example, in the interior of the drive shaft and supports the tool shaft.

[0025] The following configuration is possible both when the drive shaft is a hollow shaft that accommodates the tool shaft and when the tool shaft is a hollow shaft in which the drive shaft is accommodated.

[0026] It is expediently provided that the tool shaft protrudes in front of the drive shaft in an area facing away from the tool holder and carries one of the rolling elements, for example the planetary gear or a ring gear.

[0027] The drive motor is advantageously located between the tool holder and at least one of the rolling elements, such as a planetary gear. This results in a favorable weight distribution.

[0028] A preferred concept provides that the drive motor is arranged between the tool holder and at least one of the rolling elements and / or the freewheel device.

[0029] It is particularly preferred if the drive motor is arranged between the tool holder and the forced rotation guide.

[0030] It is possible for the drive motor to drive the drive shaft directly. For example, the drive motor is a direct drive. In particular, the drive shaft is preferably provided or formed by the motor shaft of the drive motor. The drive shaft, configured as a hollow shaft, can, for example, be the motor shaft.

[0031] However, it is also possible for the drive motor to drive the drive shaft indirectly, namely via a gearbox.

[0032] The transmission may, for example, comprise or be an angular transmission, in particular a bevel transmission.

[0033] It is also possible for the transmission to include or be a reduction gear that reduces or increases the speed of the drive motor. The transmission can also be a switchable transmission, in which, for example, a first gear ratio and a second gear ratio can be switched. For example, the transmission is a multi-speed transmission, in particular a two-speed transmission.

[0034] The transmission may include or be a planetary gear.

[0035] Preferably, the gear unit is switchable with respect to its direction of rotation. For example, the gear unit can be switched to opposite directions of rotation, so that the drive shaft can be driven by the drive motor in different directions of rotation while the drive motor's direction of rotation remains the same. The gear unit thus reverses the direction of rotation of the tool shaft from the first direction of rotation to the second direction of rotation and vice versa.

[0036] It is preferred if the drive shaft is arranged in an interior space of the drive motor. Even with this configuration, it is conceivable for the eccentric gear and / or a transmission gear to be arranged in the interior space of the drive motor, so that the drive motor drives the drive shaft via its motor shaft and a transmission.

[0037] It is particularly preferred if the drive shaft is formed by a motor shaft of the drive motor. For example, a laminated core can be arranged on the outer circumference of the drive shaft.

[0038] The drive motor is preferably electrically switchable between a first motor rotation direction and a second motor rotation direction opposite to the first motor rotation direction. When rotating in the first motor rotation direction, the drive motor drives the drive shaft, for example, in such a direction of rotation that the tool shaft rotates in the first direction of rotation, whereas when rotating in the second motor rotation direction, the drive motor drives the drive shaft in an opposite direction of rotation, so that the tool shaft rotates in the second direction of rotation. If the drive motor is a direct drive, the motor rotation direction is of course the same as the drive shaft rotation direction. However, with a gear connected between the drive motor and the drive shaft, a reversal of rotation direction can also be present in the drive train between the drive motor and the driven drive shaft of the eccentric gear.

[0039] To switch the motor rotation direction between the first and second directions, an operating switch can be provided, for example, which can be set to different switching positions. For example, a toggle switch can be provided. However, it is also possible to provide a push-button switch or another operating switch that can be actuated in a predetermined switching sequence to switch the motor rotation direction. For example, a push-button switch can be switched by pressing the button for different lengths of time, so that it or a power supply device controls the drive motor to rotate in the first or second direction of rotation.

[0040] Such an operating switch can simultaneously be the on / off switch for switching the drive motor on and off.

[0041] It is preferred if each motor rotation direction is assigned a separate operating switch so that the operator can specifically set the motor rotation direction by pressing the respective operating switch.

[0042] The drive motor is preferably an electronically commutated or brushless motor, or a motor without an electromechanical commutator. The handheld power tool has a power supply device for supplying power to the brushless or commutatorless drive motor, with which the direction of rotation of the drive motor can be switched. The power supply device has, for example, at least one half-bridge.

[0043] The brushless or electronically commutated drive motor has the advantage that it has identical or essentially identical performance in both directions of rotation. The efficiency of the electronically commutated or brushless motor is also the same or essentially identical in both directions of rotation. Unlike the universal motor or motor with brushes, which is also possible in principle and mentioned below, the electronically commutated / brushless motor has the advantage that it can be operated optimally in opposite directions of rotation. Suitable software for controlling the power supply device allows optimal operating characteristics to be set. One of the advantages of the electronically commutated or brushless motor is that there is no wear on the commutator unit, for example, regardless of the direction of rotation. The universal motor orFor example, in motors equipped with a commutator or brushes, the wear of carbon brushes or brushes varies depending on the direction of rotation.

[0044] Furthermore, with a brushless motor, changing the direction of rotation is much easier. Unlike with a universal motor or a brushed motor, this does not require complex electromechanical components that would otherwise be required to mechanically adjust a brush assembly or brush arrangement. An electrical switch or sensor, activated by the operator, is sufficient to control the control electronics or power supply for the brushless motor to change the motor's direction of rotation.

[0045] However, the principle according to the invention can also be implemented with any other electric drive motor, for example a so-called universal motor.

[0046] The drive motor could also be a pneumatic or compressed air motor. In this case, the handheld power tool advantageously has a corresponding valve arrangement for adjusting the appropriate compressed air supply.

[0047] The machine housing expediently has a handle for gripping by an operator. However, it is also possible for a handle element to protrude from the machine housing, in particular a rod-shaped handle element that is connected to the machine housing via a joint. For example, the hand-held power tool can be a ceiling or wall sander.

[0048] The drive motor is preferably arranged in or on the machine housing. The eccentric gear can have a gear housing on which at least one freewheel device is supported. However, it is also possible for the machine housing, in particular a drive section of the machine housing, to form a gear housing for the eccentric gear.

[0049] A preferred concept provides for the forced rotation guide and / or the freewheel device, on the one hand, and the tool holder, on the other, to be arranged on opposite sides of the machine housing, for example, on a top and a bottom side. In any case, it is advantageous if the forced rotation guide and / or the freewheel device are arranged in a protected area of ​​the housing and away from the tool holder and thus the disk tool, so that influences from dust, dirt, or the like are minimal.

[0050] It is advantageous if the forced rotation guide or the freewheel device, or both, are arranged far away from the tool holder in the machine housing. Thus, an advantageous concept provides for the forced rotation guide and / or the freewheel device to be arranged at an end region of the tool shaft opposite the tool holder or the disk tool, or at a wall region or upper region of the machine housing facing away from the tool holder. For example, it is provided that the freewheel device and / or the forced rotation guide are arranged below an upper cover wall of the machine housing.

[0051] An advantageous ventilation concept can be designed as follows. A fan wheel, which is driven, for example, directly or indirectly by the drive motor or can also be driven by a separate drive, is expediently arranged between the tool holder and one or more of the following components: drive motor and / or forced rotation guide and / or freewheel device. For example, the following row arrangement is provided with respect to a longitudinal axis of the tool shaft and / or drive shaft: forced rotation guide and freewheel device, drive motor, fan wheel, tool holder.

[0052] A suitable arrangement provides that an air flow generated by the fan wheel, for example, first flows through the drive motor before flowing out of the housing or cools the forced rotation guide or the freewheel or both of them on the downstream side.

[0053] A preferred cooling concept is one in which a cooling air stream flows through an air guide arrangement of the hand-held power tool at the forced rotation guide, the freewheel device, the drive motor, or combinations thereof, toward the tool holder. The cooling air stream is drawn in away from the tool holder and thus from the disc tool, where it is contaminated with relatively little or no dust.

[0054] It is expedient for the machine housing of the hand-held power tool to have at least one inlet opening in an area facing away from the tool holder, for example, on a handle section. Cooling air flows into the machine housing via the inlet opening, for example, a corresponding grille, and flows past one or more of the components explained below, namely the forced rotation guide, the freewheel device, and the drive motor. The cooling air then expediently flows out through one or more outlet openings in the machine housing. However, it is also possible for the cooling air to flow out entirely or partially in the area of ​​the disk tool or the tool holder.It is preferred if the cooling air or the cooling air flow flows out of the machine housing at the front in the working direction or directed forward in the working direction, so that the cooling air flow can flow into an area of ​​the workpiece located in front of the disk tool or the tool holder in the working direction, for example in order to blow away dust.

[0055] It is further advantageous if, particularly in the machine housing, a partition wall is arranged between the tool holder and the forced rotation guide and / or the freewheel device and / or the drive motor. This partition wall isolates the forced rotation guide, the freewheel device, or the drive motor, or several of them, from a dust-laden area of ​​the hand-held power tool. The dust is generated by the disc tool during operation of the hand-held power tool, for example, when grinding a workpiece. The partition wall forms a kind of bulkhead or insulation wall.

[0056] The partition wall can, for example, be formed or provided entirely or partially by a fan wheel. The fan wheel is preferably arranged close to the tool holder. The fan wheel can, for example, form a kind of floor of the machine housing and thus a dividing plane between the tool holder and the drive components, in particular the drive motor, the eccentric gear, the forced rotation guide, or the like.

[0057] A sealing arrangement, in particular a labyrinth seal, is expediently provided between the fan wheel and the machine housing.

[0058] A preferred concept provides for the cooling air flow to be sucked in by the fan wheel past the drive components, in particular the drive motor and / or the forced rotation guide and / or the freewheel device, and then blown out of the machine housing in a region of the machine housing close to the tool holder or close to the disc tool. The fan wheel, in turn, forms a partition or dividing plane to a dust area of ​​the hand-held power tool, in which the tool holder or the disc tool is located. From this dust area, dusty air flows, for example, to a dust outlet or suction connection. A suction device can expediently be connected to the dust outlet.

[0059] Of course, it is possible for the hand-held power tool to have a blower or similar other means for generating a dust air flow or for conveying dust-laden air away from the working area of ​​the disc tool.

[0060] It is also advantageous if the forced rotation guide and / or the freewheel device are protected in a capsule housing or gear housing. The capsule housing or gear housing is expediently a housing that is completely separate from the machine housing. However, it is also possible for the capsule housing or gear housing to be at least partially formed by the machine housing, for example by an outer wall. The capsule housing of the gear housing expediently has an opening that is sealed by a bearing. The opening serves, for example, to accommodate the drive shaft or the hollow shaft or the motor shaft or the tool shaft, wherein the respective shaft is expediently rotatably mounted relative to the gear housing or capsule housing by the bearing.

[0061] An embodiment of the invention is explained below with reference to the drawings. They show: Figure 1a perspective oblique view of a hand-held power tool, Figure 2a cross-section through a front section of the hand-held power tool according to Figure 1 , approximately along a section line AA in Figure 1 , Figure 3 shows a side view of the motor housing and a freewheel arrangement of a variant of the hand-held power tool according to the preceding figures, of which Figure 4 shows a cross-sectional view along a section line BB in Figure 3 Figure 5 shows a section approximately along a section line C, C in Figure 3 by a freewheel arrangement of the gearbox in a neutral position, Figure 6the freewheel arrangement according to Figure 5 in a locking position, Figure 7the freewheel arrangement according to Figure 5 in a freewheeling position and Figure 8 shows a schematic further embodiment of the invention in a cross-sectional view.

[0062] A hand-held power tool shown in the drawing is preferably suitable for grinding and / or polishing surfaces. For example, the hand-held power tool is a grinding machine 10.

[0063] The grinding machine 10 has a machine housing 11, which can be comfortably grasped by an operator at a handle portion 12. The handle portion 12 protrudes from a drive portion 13. A disk tool 14, for example, a grinding disk 15, is arranged on the drive portion 13. The grinding disk 15 can integrally comprise an abrasive or have a detachable abrasive 16 arranged on its underside. An upper side 17 of the grinding disk 15 faces the machine housing 11.

[0064] The sanding disc 15 or the disc tool 14 is essentially located beneath a cover 18 of the sanding machine 10, i.e., it is covered from above. The cover 18 comprises an elastic seal 19, for example, a sealing sleeve, which rests against the upper side 17 of the disc tool 14. The cover 18 is thus arranged in a substantially dust-tight manner above the sanding disc 15 or on the sanding disc 15, so that, for example, dust can be extracted from a working area of ​​the sanding disc 15, i.e., in the area of ​​the abrasive 16, through a suction channel 21 extending beneath the handle section 12. The suction channel 21 ends in a suction connection 22, to which, for example, a suction hose of a vacuum cleaner can be connected.

[0065] On the side of the drive section 13 facing the handle section 12, there is expediently a switch 23 with which the grinding machine 10 can be switched on or off. For example, the switch 23 is a push button switch. The switch 23 can be used to switch on or off a power supply device 25, which serves to supply power to a drive motor 30. A direction of rotation switch 24 can be used to switch the direction of rotation of the drive motor 30. The power supply device 25 is responsible for supplying power to the drive motor 30 in the direction of rotation set by the direction of rotation switch 24.

[0066] The power supply device 25 comprises, for example, a circuit with half-bridges, which is known per se. The drive motor 30 is expediently a brushless drive motor, in particular a commutatorless or electronically commutated drive motor. However, the drive motor 30 could also easily be a so-called universal motor, have a commutator, or the like. Furthermore, a compressed air motor or pneumatic motor can also be used as the drive motor. In any case, it is advantageous if the direction of rotation of the drive motor 30 can be switched, for example by appropriate current supply using the power supply device 25. In the case of a pneumatic motor or compressed air motor, the direction of rotation can be switched by appropriately applying compressed air.In the case of a drive motor having a commutator or brush device, for example, the brush device or commutator can be adjusted to set the direction of rotation of the drive motor.

[0067] The drive motor 30 has a stator 31, within whose interior a rotor 32 is rotatably mounted. The drive motor 30 also has an excitation coil assembly 33, which is energized by the energizing device 25. The excitation coil assembly 33 is arranged on a laminated core 34, which enables optimal magnetic flux.

[0068] The rotor 32 is arranged on a drive shaft 35, i.e., a motor shaft. The drive motor 30 is a direct drive. However, this should not be understood to mean that a drive concept with a transmission gear, for example, a bevel gear and / or a speed-changing gear (transmission gear) or a gear in which the direction of rotation of an output of the gear is switchable, is not within the scope of the invention. This will be discussed in connection with Figure 8 clearly.

[0069] The drive shaft 35 is designed as a hollow shaft 36. The drive shaft 35 is rotatably mounted on bearings 37 and 38 relative to the machine housing 11. The bearings 37 and 38 are spaced longitudinally apart from a rotational axis D around which the drive shaft 35 rotates.

[0070] The bearings 37, 38 are arranged, for example, on bearing receptacles 46, 47 of a stator body 45 of the drive motor 30. A retaining projection 48, for example, protrudes in front of the stator body 45 and supports a retaining body 70.

[0071] The drive motor 30 has a fan wheel 39 that is non-rotatably connected to the drive shaft 35. For example, the fan wheel 39 is located next to the lower bearing 38 or at the longitudinal end of the drive shaft 35 associated with the disc tool 14.

[0072] The hollow shaft 36 has an interior space H in which a tool shaft 50 is rotatably received. A tool holder 51 for the disc tool 14 is provided at a longitudinal end 52a of the tool shaft 50. The longitudinal end 52a protrudes from the drive shaft 35. The tool holder 51 has, for example, bayonet contours and / or a screw thread and / or a plug-in receptacle or similar other holding means for holding a disc tool. For example, the disc tool 14 is attached to the tool shaft 50 by means of a screw 53.

[0073] The tool shaft 50 is rotatably mounted on the drive shaft by tool shaft bearings 42, 44 spaced apart from each other with respect to the drive axis D. For example, the tool shaft bearings 42, 44 are provided on bearing receptacles 41, 43 in the interior H of the hollow shaft 36 or drive shaft 35.

[0074] The tool shaft bearing 42 is, for example, a ball bearing. The tool shaft bearing 42 is provided, for example, in the region of the longitudinal end 52a.

[0075] In the region of a longitudinal end 52b opposite the longitudinal end 52a, the tool shaft 50 is mounted on the drive shaft 35 by means of the tool shaft bearing 44. The tool shaft bearing 44 is, for example, a needle bearing.

[0076] The tool shaft bearings 42, 44 support the tool shaft 50 rotatably with respect to the drive axis D, but not concentrically, but eccentrically with an eccentricity E. A tool rotation axis W of the tool shaft 50 has the eccentricity E to the drive axis D.

[0077] Due to friction of the tool shaft bearings 42, 44, the tool shaft 50 is driven by the drive shaft 35 when the drive motor 30 causes the drive shaft 35 to rotate. In principle, the tool shaft 50 would reach the rotational speed of the drive shaft 35 unless the disc tool 14 is placed on a workpiece, which leads to deceleration of the tool shaft. However, if the disc tool 14 lifts off the workpiece, without the action of a brake on the disc tool 14 or the tool shaft 50, the rotational speed of the disc tool 14 would increase undesirably, so that the disc tool 14 rotates at high speed upon re-positioning on the workpiece, which leads to damage to the workpiece and / or premature wear of the disc tool 14 or the abrasive 16.

[0078] Therefore, braking means are provided in the form of, for example, brake bodies 20, which are fixed in position relative to the machine housing 11, for example, on the cover 18. The brake bodies 20 brake the disc tool 14. The brake bodies 20 13 act, for example, on the upper side 15 of the grinding disc 15 or the disc tool 14. Alternatively or additionally, the elastic seal 19 or the cover 18 on the upper side 17 of the disc tool 14 can of course also have a braking effect.

[0079] However, the handheld power tool 10 also allows the tool shaft 50 to undergo eccentric rotational movements or so-called hypercycloidal movements in a controlled manner, for which a forced rotation guide 54 is provided. The forced rotation guide 54 comprises rolling elements 55, 57 that are in frictional or positive engagement with one another, so that, for example, the rolling element 55 rolls against the rolling element 57 when the forced rotation guide 54 is active.

[0080] The rolling element 55 is, for example, a gear 56 or a sun gear, which is arranged in an interior of the rolling element 57 designed as a ring gear 58 and rolls on its inner circumference, for example with intermeshing toothings.

[0081] The rolling element 55, for example, is assigned to the tool shaft 50. The rolling element 57, on the other hand, is assigned to the machine housing 11.

[0082] The rolling element 55 is connected to the tool shaft 50 in a rotationally fixed manner.

[0083] The rolling element 57 could now, for example, be brought into engagement and disengaged from the rolling element 55 on one side by being axially displaced, for example by being displaced along the drive axis D or the like. However, to deactivate the effect of the rolling element 57 and thus the forced rotation guide 54, a different concept has been chosen: In order to deactivate the rolling element 57, so to speak, the rolling element 57 is essentially rotatably mounted on the machine housing 11 by means of a bearing 61. If the rolling element 57 can rotate relative to the machine housing 11 by means of the bearing 61, it is carried along by the other rolling element 55, i.e. the rolling element 55 cannot be set into rotation by rolling on the rolling element 57.Thus, the rolling element 55 can rotate freely in the machine housing 11 and also freely with respect to the drive shaft 35 or with respect to the drive axis A, so that the previously explained free rotation eccentric mode is present, in which the braking means 20 act, but no forced rotation guide 54 is active.

[0084] It is also possible that the bearing 61 has such a braking torque that it brakes the rolling element 57 to such an extent that the rolling element 57 cannot be driven completely freely by the rolling element 55, but that a certain torque is transmitted from the rolling element 57 to the rolling element 55.

[0085] The bearing 61 is arranged, for example, on the outside on an outer circumference of a bearing projection 59 of the rolling element 57 and is held on a holding body 70. The holding body 70 is stationary with respect to the machine housing 11. The rolling element 57 or the ring gear 58 is therefore rotatably mounted with respect to the machine housing 11 by means of the bearing 61. The holding body 70 has, for example, a holding projection 71 with which it is connected to the stator body 45, for example engaging in a receptacle of the stator body 45. A bearing receptacle 72 for the bearing 61 is also provided on the holding body 70. With a holding area 73, the holding body 70 projects radially inward towards the axis of rotation D. A holding section 74 projects from the holding area 73.

[0086] A freewheel device 62 of the freewheel arrangement 60 is connected to the holding section 74 and the bearing projection 59 of the ring gear 58 or the rolling element 57. On the one hand, a freewheel part 63 of the freewheel device 62, which is arranged radially outward, for example, is connected to the bearing projection 59, and on the other hand, a freewheel part 64, which is arranged radially inward, for example, is connected to the holding section 74. The freewheel parts 63, 64 are, for example, components of a freewheel bearing 65. The freewheel parts 63, 64 cannot rotate relative to one another in a first direction of rotation D1 of the tool shaft 50, and thus support one another, so that the rolling element 57 is rotationally fixed with respect to the machine housing 11 via the freewheel device 62 and the holding body 70. Thus, the other rolling element 57, the planetary gear, rolls on the inside of the ring gear 58, so that a so-called hypercycloid movement is imposed on it, so that the forced rotation guide 54 is active.In this case, the freewheel device 62 is in its locked position.

[0087] In a second direction of rotation D2, the freewheel parts 63, 64 can rotate relative to each other, so that the rolling element 57 is no longer supported with respect to the machine housing 11 and the rolling element 55 can drive the rolling element 57 along, thus, apart from the bearing friction of the freewheel device 62, it can essentially rotate relatively freely. In this case, the tool shaft 50 is driven freely by the drive shaft 35, but is still braked by the brake bodies 20. This has already been explained. The direction of rotation D2 corresponds to the freewheeling direction of the freewheel device 62. In the direction of rotation D2, for example, the free rotation eccentric mode is active.

[0088] Therefore, by simply reversing the direction of rotation of the drive motor 30, it is possible to switch between the forced rotation eccentric mode and the free rotation eccentric mode.

[0089] For example, to reverse the direction of rotation of the drive motor 30, the direction switch 24 must be activated. Complex mechanical actuation elements are not necessary. A simple electrical switch is sufficient.

[0090] A symbol F for particularly fine workpiece machining can signal to the operator that the free rotation eccentric mode can be set in this way. For example, the symbol F is assigned to the direction of rotation D2. The symbol G indicates a coarser workpiece machining, which corresponds to the forced rotation eccentric mode and thus to the direction of rotation D1. The symbols F and G are located, for example, next to the direction of rotation switch 24 or assigned to its two switching positions.

[0091] However, it is also possible for the two rotation directions D1 and D2 or the two eccentric modes, symbolized by the symbols F and G, to be assigned a dedicated actuation switch 24a and 24b, respectively. By pressing one of the two actuation switches 24a or 24b, the direction of rotation of the drive motor 30 can be switched, thus enabling switching between the free-rotation eccentric mode and the forced-rotation eccentric mode with a simple button press.

[0092] Furthermore, it is possible to effect an electrical reversal of the rotation direction of the drive motor 30 by means of a specific key sequence, for example, by triggering a corresponding long or short press of the switch 30. For example, a switching sequence of two or three short presses of the switch 30 can be assigned to the rotation direction D1 and thus to the forced rotation eccentric mode, while two or three long presses of the switch 30 with predetermined pauses are assigned to the rotation direction D2 and thus to the free rotation eccentric mode.

[0093] The freewheel device 62 and the forced rotation guide 54 are optimally arranged in the handheld power tool 10 with regard to cooling and minimal interference from dust and other dirt. For example, the freewheel device 62 and the forced rotation guide 54 are arranged in an area of ​​the machine housing 11 remote from the tool holder 51 and thus from the disk tool 14, preferably below a wall area 11b. The wall area 11b is arranged, for example, on a top side of the housing or at the top of the drive section 13.

[0094] Furthermore, the freewheel device 62 and the forced rotation guide 54 are arranged in a capsule housing 80. The capsule housing 80 could also be referred to as a gear housing or be a gear housing. The capsule housing 80 has a sub-housing 81 (lower in the drawing) and a sub-housing 82 (upper in the drawing), which enclose the freewheel device 62 and the forced rotation guide 54 in a shell-like manner. The part of the capsule housing 80 facing the drive motor 30, or the sub-housing 81, is formed, for example, by the region of the stator body 45 or the retaining projection 48 facing away from the excitation coil arrangement 33. The stator body 45, the retaining projection 48, or the sub-housing 81 are, for example, shell-shaped. The part of the capsule housing 80 or the partial housing 82 further away from the drive motor 30 is provided by the holding body 70, which in the manner of a lid supports the holding projection 48 orcovers the receptacle provided by the latter for accommodating the freewheel device 62 and the forced rotation guide 54. The partial housings 81, 82 are screwed together, for example, using one or more screws 83. It is preferred if the partial housings 81, 82 are connected to one another with stepped contours 84 and / or labyrinth seals.

[0095] An elastic seal, for example an O-ring, may also be provided between the partial housings 81 and 82.

[0096] The sub-housing 81 has the bearing mount 46 for the bearing 37 of the drive shaft 35 / motor shaft. The bearing 37 simultaneously seals the interior of the capsule housing 80 against the ingress of dust or the like. The bearing 37 forms a seal for the sub-housing 81 and thus the capsule housing 80.

[0097] As an alternative or in addition to the concept of encapsulating the freewheel device 82 and the forced rotation guide 54 against dust by means of the capsule housing 80, the concept of dust insulation mentioned below is advantageous.

[0098] A region of the machine housing 11 facing the disk tool 14 and located at the bottom in the drawing is a dust area, so to speak, that communicates with the extraction channel 21. The forced rotation guide 54 and the freewheel arrangement 60 are not only spatially separated from it, but are also separated by a partition wall 90.

[0099] The partition wall 90 is stationary relative to the longitudinal axis of the drive shaft 35, but rotatable. It is provided by a base wall of the fan wheel 39. A sealing arrangement 91 is provided between an outer circumference of the fan wheel 90 and the machine housing 11. The sealing arrangement 91 comprises, for example, a labyrinth seal 92.

[0100] On the side of the fan wheel 90 facing the disc tool 14, an extraction chamber 96 is provided, which communicates with the extraction duct 21. When dusty air S is extracted via the extraction duct 21, the pressure in the extraction chamber 96 is lower than in the area of ​​the fan wheel 39 facing away from the extraction chamber 96 and towards the drive motor 30, so that dusty air S does not flow into the area of ​​the drive motor 30 and ultimately into the area of ​​the forced rotation guide 54 and the freewheel arrangement 60, but rather, conversely, at most from this so-called clean area or fresh air area towards the extraction chamber 96. As a result, the dust load on the drive motor 30 and the forced rotation guide 54 as well as the freewheel arrangement 60 is low.

[0101] The dust air S can, for example, flow through through openings 96 on the sanding disc 15 or disc tool 14 toward the extraction channel 21 in an area 94 between the cover 18 and the sanding disc 15. The cover 18, in turn, has through openings 95 so that the dust air S can flow from the area 94 into the extraction chamber 96 and ultimately into the extraction channel 21.

[0102] Furthermore, the cooling concept of the hand-held power tool 10 explained below optimally contributes to the drive motor 30 and / or the freewheel arrangement 60 and / or the forced rotation guide 54 being optimally cooled and, in particular, being exposed to little or no dust.

[0103] A cooling air flow K is generated by the rotation of the fan wheel 39. The cooling air flow K flows into the machine housing 11 via inlet openings 97, preferably on the handle section 12 or at least on a section of the machine housing 11 remote from the tool holder 51, flows through the machine housing 11, and flows out through outlet openings 98. The outlet openings 98 are preferably provided on the drive section 13. Thus, the cooling air flow K preferably flows past the energization device 25 to cool it. The cooling air flow K continues to flow past the freewheel arrangement 60 or the freewheel device 62, cooling it as well as the forced rotation guide 54. The cooling air flow K then flows past the drive motor 30 and in particular through the excitation coil arrangement 33, so that the drive motor 30 is also optimally cooled.The cooling air K heated in this way then flows sideways, preferably forwards in the working direction as in . Figure 1 shown, from the machine housing 11. Thus, the cooling air K is drawn in away from the working area of ​​the disc tool 14, where the dust load is low. The cooling air K then flows in the direction of the disc tool 14, so that it can preferably also contribute to clearing the working area of ​​the disc tool 14 or an area X located forward of the working area of ​​the disc tool 14 in the working direction, for example, of dust or other contaminants.

[0104] In the case of a Figures 3 to 7The only partially illustrated hand-held power tool 110 essentially contains the same components as the previously described hand-held power tool 10, in particular the drive motor 30 designed as a direct drive. The drive motor 30 is not shown or is only shown schematically, as is its drive shaft 35, but the tool shaft 50 arranged in the drive shaft 35 and driven by the drive shaft 35 is. At the upper longitudinal end region of the tool shaft 50, the rolling element 55, designed, for example, as a planetary gear, is provided, which can in principle roll on the rolling element 57 designed as a ring gear 58 when a freewheel arrangement 160 with a freewheel device 162 is in its locked position. The rolling element 55 can drive the rolling element 57 when the freewheel device 162 assumes its freewheeling position. The associated directions of rotation D1 and D2 of the tool shaft 50 are shown in the Figures 6 and 7 marked.

[0105] The drive motor 30 is arranged, for example, in a motor housing 145, for example in an interior space of the motor housing 145 delimited by a peripheral wall 147. A drive shaft or motor shaft of the drive motor 30, not visible in the drawing, is mounted, for example, by the bearing 37 already explained, which in turn is received in a bearing receptacle 146 of the motor housing 145.

[0106] On the end face or end wall 149a facing the freewheel device 162, the motor housing 145 has a number of multiple passage openings 149 for cooling air for cooling the drive motor 35.

[0107] A retaining projection 148 protrudes from the end wall or end face 149a, which serves to hold a retaining body 170. The retaining body 170 essentially serves to hold the freewheel device 160 stationary relative to the machine housing 11 and also to hold a bearing arrangement with a bearing 161 for rotatably supporting the rolling element 57. The retaining body 170 is provided, for example, with a retaining projection 171, which is connected to the retaining projection 148 of the motor housing 145. For example, corresponding plug receptacles and plug projections engage with one another.

[0108] For example, the retaining projection 171 protrudes from a retaining area 173 in the direction of the rotation axis D. The retaining area 173 is designed, for example, in the manner of an end wall. A bearing receptacle 174 for the bearing 161 is provided on the retaining area 173, for example.

[0109] With respect to the rotational axis D, a bearing projection 159 protrudes in front of the rolling elements 57, on whose radial outer circumference the bearing 161 is provided. The bearing projection 159 is designed, for example, in the form of a pin or a sleeve.

[0110] The bearing 161 is arranged between the holding area 173, in particular the bearing receptacle 174, of the holding body 170, which is stationary with respect to the machine housing 11, and the bearing projection 159.

[0111] Between these two components, the bearing holder 174 and the bearing projection 159, the freewheel device 162 is also provided, which has a freewheel part 163, which is connected to the ring gear 58 or the rolling element 57, and a freewheel part 164, which can be fixed in a locking direction corresponding to a direction of rotation D1 with respect to the machine housing 11, namely with respect to the holding body 170, while in a direction of rotation D2 a freewheeling position is assumed, in which the freewheel part 164 and thus the rolling element 57 can rotate relative to the machine housing 11.

[0112] The retaining projection 148 forms a partial housing 181, and the retaining body 170 forms a partial housing 182 of a capsule housing 180. The capsule housing 180 houses the forced rotation guide 54. The partial housings 181, 182 engage with each other via stepped contours or a labyrinth seal 183.

[0113] The bearing 137 seals an opening in the partial housing 181 through which the drive shaft of the drive motor 30 penetrates the capsule housing 180, and rotatably supports the drive shaft 35 of the drive motor 30. The bearing 161 is expediently completely or at least partially covered by a cover wall 184 of the partial housing 182 or the capsule housing 180.

[0114] The capsule housing 180 and thus the freewheel assembly 160 and the forced rotation guide 54 are also arranged in the upper area of ​​the machine housing 11, at least far away from the disk tool 14. This reduces or prevents any influence or contamination by dust.

[0115] Between the freewheel part 163 and the freewheel part 164, a gap 169 is provided, in which a number of blocking bodies 165, for example, rotation-blocking bodies 165, are movably received. The blocking bodies 165 can move, e.g., roll, around the rotation axis D in the gap 169. The blocking bodies 165 are expediently balls, rollers, or the like.

[0116] In the direction of rotation D2, the freewheeling direction of the freewheel device 162, which corresponds to a free-rotation eccentric mode, the blocking bodies 165 are received in driving recesses 166 provided on the outer circumference of the freewheel part 163. The driving recesses 166 are deep enough that the blocking bodies 165 do not cause the freewheel parts 163, 164 to jam or become blocked relative to one another. The distance between the bottom of a respective driving recess 166 and the inner circumference of the freewheel part 164 is greater than the diameter of a blocking body 165.

[0117] For example, the driving recesses 166 are provided next to driving projections 166a, which are provided for rotationally driving the blocking bodies 165 in the direction of rotation D2 and thus ensure that the blocking bodies 165 enter the driving recesses 166 in the direction of rotation D2. When the blocking bodies 165 are in the driving recesses 166, they no longer rest against the radial inner circumference of the freewheel part 164, so that the freewheel parts 163, 164 can rotate relative to each other. Thus, the freewheel part 163 and thus the rolling element 57 are rotatable relative to the machine housing 11.

[0118] In the direction of rotation D1, however, the blocking bodies 165 emerge from the driving recesses 166, for example, by being thrown or displaced radially outward from the driving recesses 166 due to centrifugal forces. They then reach wedge bevels or blocking bevels 168, which are provided, for example, on the rear sides of the driving projections 166a. The wedge bevels 168 are so close to the inner circumference of the freewheel part 164 that the blocking bodies 165 become wedged between the wedge bevels 168 and the inner circumference of the freewheel part 166, so that the freewheel part 163 is blocked relative to the freewheel part 164, i.e., assumes its locking position. Thus, the ring gear 58 or the rolling element 57 can no longer rotate, which is why the other rolling element 55 rolls on the inner circumference of the rolling element 57, so that ultimately the forced rotation eccentric mode is set.

[0119] In this case, too, switching between different eccentric modes is easily possible by simply reversing the direction of rotation of the drive motor 35.

[0120] In the schematically indicated embodiment according to Figure 8A drive motor 230, for example a universal motor, a brushless motor, a pneumatic motor, or the like, is arranged in a machine housing 211, which drives a drive shaft 235 via a gear arrangement or a gear 280. The gear arrangement comprises, for example, a transmission gear 281 and / or a switching gear 284 for reversing the direction of rotation and / or an angular gear 287. This creates a complex drive train, which can of course also be designed simply. Overall, for example, an integrated transmission with one or more functions can also be provided, in which, for example, the functions of the transmission gear and the angular gear are implemented by a transmission unit.

[0121] The output of the drive motor 230 thus initially drives the transmission gear 281. Using an actuating element 282, for example, a first gear stage and a second gear stage, which represent different transmission ratios, can be engaged. The actuating element 282 protrudes, for example, in front of the machine housing 211.

[0122] The output 283 of the transmission gear 281 drives the direction-of-rotation gear or manual transmission 284. With the manual transmission 284, which can be actuated via an actuating element 285, the direction of rotation of an output 286 of the manual transmission 284 can be switched, for example. Thus, while the direction of rotation of the drive motor 230 remains the same, switching between a first and a second direction of rotation of the drive shaft 235 is possible.

[0123] The drive motor 230 can, for example, be arranged in a handle section of the machine housing 211, similar to the handle section 12, which is not shown in simplified form in the drawing. In any case, the axial direction of the drive motor 230 is angular to the axial direction of the drive shaft 235, for example, at right angles. The corresponding power transmission between the drive motor 230 and the drive shaft 235 takes place via the angular gear 287, for example, a bevel gear. It should be noted at this point that the angular gear 287 can also, for example, have a transmission ratio between the drive motor 230 and its output, which is coupled to the drive shaft 235 or forms the drive shaft 235.

[0124] The drive shaft 235 extends into an interior space of a tool shaft 250 configured as a hollow shaft 236. The tool shaft 255 is rotatably mounted on the drive shaft 235, for example, via tool shaft bearings 242 and 244 spaced apart from one another with respect to a rotational axis D of the drive shaft 235. The previously explained disc tool 14, for example, a grinding disc 15 or polishing disc with a polishing agent or abrasive 16, is arranged on the free end region of the tool shaft 250 in a manner not shown in detail via a tool holder 51. In any case, the drive shaft 235 essentially drives the tool shaft 250 via the bearing friction of the tool shaft bearings 242, 244.

[0125] A rotational axis W of the tool shaft 250 and the rotational axis D of the drive shaft 235 have an eccentricity E, so that an eccentric gear 240 is realized. To decelerate the disk tool 14 in a free-rotation eccentric mode, a braking device with braking bodies 20 is provided, which are indicated schematically.

[0126] To illustrate various variants of the invention, freewheel arrangements 260, 360 are provided, which are explained below. For example, a rolling element 255 of a forced rotation guide 254 is connected to the tool shaft 250 via a freewheel device 262. The rolling element 255, for example a planetary gear, can roll on the inner circumference of a rolling element 257 configured as a ring gear and stationary with respect to the machine housing 211 when the freewheel device 262 assumes its locking direction. For example, the rolling element 257 is arranged on retaining projections 248 that protrude radially inward toward the tool shaft 235 in front of side walls 249 of the machine housing 211.

[0127] The freewheel device 262 is shown only schematically. For example, it has freewheel parts 263, 264 that cannot rotate relative to one another in the direction of rotation D1, i.e., they assume the locked position, while they can rotate relative to one another in the direction of rotation D2 of the drive shaft 235. The freewheel device 262 is therefore in freewheeling mode in the direction of rotation D2. The free-rotation eccentric mode is then set. An operator achieves this changeover quite simply by switching the switching gear 284 between the two directions of rotation D1 and D2. Although a mechanical switching between the eccentric modes is necessary, this nevertheless offers a significant advantage: the switching device does not have to be located directly in the area of ​​the tool shaft or drive shaft, but can be ergonomically positioned, for example, on a handle, where the direction of rotation can be changed using the actuating element 282.

[0128] In the above embodiments, the ring gear was assigned to the machine housing, and the planet gear to the tool shaft. However, a reverse arrangement is also possible, as indicated by a freewheel device 362 of the freewheel arrangement 360. In this case, for example, a rolling element 355 assigned to the tool shaft 250 is designed as a ring gear, on whose radial inner circumference a rolling element 357, a planet gear, so to speak, can roll when the forced rotation guide 354 is active. For example, a freewheel part 363 of the freewheel device 362 is connected to the rolling element 355, while a freewheel part 364 is connected to the tool shaft 250.

[0129] The planetary gear or the rolling element 357 could, in principle, also be connected to the machine housing 211 via a freewheel device, for example, using a freewheel device 462. The freewheel device 462 could, for example, enable free rotation of the rolling element 357 relative to the machine housing 211 in the direction of rotation D2. It is also possible for the freewheel device 462 to, in principle, enable rotation of the rolling element 357 relative to the machine housing in the freewheeling position or the direction of rotation D2, but with a certain degree of restriction or viscosity. For example, the freewheel device 462 contains a fluid, for example, oil, which, in the freewheeling position, enables relative rotation of freewheeling parts of the freewheel device 462, but with a braking torque or with a rotational restriction.Thus, although the positive guide 354 is not fully active, it nevertheless imposes a certain hypercycloid torque on the tool shaft 250 in the freewheeling position of the freewheeling device 462.

[0130] Advantageously, however, the rolling element 357 is fixedly arranged on retaining projections 348, which protrude, for example, from a peripheral wall of the machine housing 211. In the direction of rotation D1, the freewheel parts 363 and 364 are not rotatable relative to one another, which is why the ring gear or the rolling element 355 rolls on the outer circumference of the rolling element 357. For example, friction surfaces or even a toothing are provided between the rolling elements 355 and 357. In the direction of rotation D2, however, the freewheel parts 363 and 364 can rotate relative to one another, which is why the rolling element 355 can remain stationary with respect to the machine housing 211. In this case, the tool shaft 250 rotates freely with respect to the machine housing 211, apart from braking by the braking elements 20.

[0131] A partition wall 290, which is stationary relative to the machine housing and penetrated only by the hollow shaft 236, separates an extraction chamber 296 of the hand-held power tool 210, which faces the disk tool 14 and is fluidly connected to the extraction channel 21, from an area of ​​the machine housing 211 in which, for example, the drive motor 230 and / or the forced rotation guides 354, 254 and the freewheel devices associated with them are arranged. The extraction chamber 296 can be extracted via the previously explained extraction channel 21 and the suction connection 22. Dust air S can flow into the extraction chamber 296 via inlet openings 93 on the disk tool 14.

Claims

1. Hand-held power tool, in particular grinding machine (10) and / or polishing machine, having an eccentric gear mechanism (40) located in a machine housing (11) and an electric or pneumatic drive motor (30) for rotationally driving a drive shaft (35) of the eccentric gear mechanism (40) about a drive axis (A), wherein the eccentric gear mechanism (40) has a tool shaft (50), which is mounted in an eccentrically rotatable manner on the drive shaft (35) by means of at least one tool shaft bearing (42, 44) to perform eccentric movements and which has a tool holder (51) for a disc tool (14), in particular a grinding disc (15) or polishing disc, wherein a forced rotation guide (54) is provided which, in a forced rotation eccentric mode, forces the tool shaft (50) to perform rotary movements with respect to the machine housing (11) by providing that a rolling body (55) of the forced rotation guide (54) rolls against another rolling body (57) of the forced rotation guide (54), wherein one rolling body (57) is supported on the machine housing (11) and the other rolling body is supported on the tool shaft (50), wherein, between at least one of the rolling bodies (57) and the tool shaft (50) or the machine housing (11), a freewheel device (62) is provided, which supports the at least one rolling body (57) on the machine housing (11) or on the tool shaft (50) in a first direction of rotation of the tool shaft (50) corresponding to a blocking direction of the freewheel device (62) with a supporting force suitable for the rolling of the other rolling body (55), being in particular coupled rotatably, so that the one rolling body (55) supported on the tool shaft (50) can roll against the other rolling body (57) supported on the machine housing (11), and in a second direction of rotation of the tool shaft (50) corresponding to a freewheeling direction of the freewheel device (62), enables it to rotate, so that the tool shaft (50) is rotatable with respect to the machine housing (11) without a relative rotation of the rolling bodies (55, 57), characterised in that the drive shaft (35) has a hollow shaft (36) or is designed as a hollow shaft (36), in which the tool shaft (50) is located.

2. Hand-held power tool according to claim 1, characterised in that one of the rolling bodies (55) is a planetary gear and the other rolling body (57) is a ring gear (58) accommodating the planetary gear, wherein it is advantageously provided that the ring gear (58) is assigned to the machine housing (11) and the planetary gear is assigned to the tool shaft (50).

3. Hand-held power tool according to any of the preceding claims, characterised in that the rolling bodies have a toothing or are gear wheel bodies, or in that there is a frictional connection between the rolling bodies.

4. Hand-held power tool according to any of the preceding claims, characterised in that only one of the rolling bodies (57) is supported with respect to the tool shaft (50) or the machine housing (11) by means of a freewheel device (62), or in that each of the two rolling bodies is supported with respect to the tool shaft (50) or the machine housing (11) by means of a freewheel device (62).

5. Hand-held power tool according to any of the preceding claims, characterised in that the at least one freewheel device (62) blocks or inhibits the rolling body (57) supported thereon in the blocking position with respect to a component supporting rotation against the freewheel device (62) - the machine housing (11) or the tool shaft (50) - and / or in that the at least one freewheel device (62) forms a part of a bearing (65) or is located at a bearing with which the rolling body (57) is rotatably mounted with respect to the machine housing (11) or the tool shaft (50), wherein it is advantageously provided that the bearing (65) is a rolling bearing, in particular a ball bearing.

6. Hand-held power tool according to any of the preceding claims, characterised in that the tool shaft (50) is accommodated eccentrically in the drive shaft (35), and / or in that the tool shaft (50) projects in front of the drive shaft (35) in a region averted from the tool holder (51) and carries one of the rolling bodies (57).

7. Hand-held power tool according to any of the preceding claims, characterised in that the drive motor (30) is located between the tool holder (51) and at least one of the rolling bodies (57) and / or the freewheel device (62) and / or the forced rotation guide (54), and / or in that the drive motor (30) is a brushless and / or electronically commutated motor, and / or in that the drive shaft (35) is located in an interior of the drive motor (30), and / or in that the tool shaft (50) and the drive shaft (35) rotate in the same direction.

8. Hand-held power tool according to any of the preceding claims, characterised in that the drive shaft (35) is represented by a motor shaft of the drive motor (30), and / or in that the drive motor (30) drives the drive shaft (35) directly, or in that a gear mechanism (284), which can be shifted with respect to its direction of rotation and / or its gear ratio in particular, and / or an angular gear (287) and / or a transmission gearing (281) are / is located between the drive motor (30) and the drive shaft (35).

9. Hand-held power tool according to any of the preceding claims, characterised in that the drive motor (30) can be switched electrically, in particular electronically, between a first direction of motor rotation and a second direction of motor rotation opposed to the first direction of motor rotation, wherein it is advantageously provided that it has, for switching the direction of motor rotation, a switch (30) to be operated in a predetermined switching sequence or an operating switch (24) capable of being moved into different switching positions or an operating switch (24a, 24b) assigned to each of the first direction of motor rotation and the second direction of motor rotation.

10. Hand-held power tool according to any of the preceding claims, characterised in that the tool shaft (50) is in the second direction of rotation in a free rotation eccentric mode in which the tool shaft (50), by virtue of a bearing friction of the at least one tool shaft bearing (42, 44), performs rotary movements at a rotation of the drive shaft (35) and is freely rotatable with respect to the drive axis (A), the hand-held power tool expediently having braking means for braking the tool shaft (50) or the tool in the free rotation eccentric mode.

11. Hand-held power tool according to any of the preceding claims, characterised in that the forced rotation guide (54) and / or the freewheel device (62) are / is located in an end region of the tool shaft (50) opposite the tool holder (51) and / or in a wall region (11b) of the machine housing (11) averted from the tool holder (51) and / or outside a dust-laden air flow (S) from the working area of the disc tool (14).

12. Hand-held power tool according to any of the preceding claims, characterised in that the forced rotation guide (54) and / or the freewheel device (62) are / is located in a completely or substantially closed capsule housing (80), wherein it is advantageously provided that at least one opening of the capsule housing (80) is sealed by a bearing (37), and / or in that the capsule housing (80) has sub-housings (81, 82), which house the forced rotation guide (54) and / or the freewheel device (62) in the manner of a shell.

13. Hand-held power tool according to any of the preceding claims, characterised in that a fan wheel (39) driven by the drive motor (30) or directly in particular is located between the tool holder (51) and the drive motor (30) and / or between the tool holder (51) and the forced rotation guide and / or between the tool holder (51) and the freewheel device (62).

14. Hand-held power tool according to any of the preceding claims, characterised in that a partition (90) is located between the tool holder (51) on the one hand and the forced rotation guide (54) and / or the freewheel device (62) and / or the drive motor (30) on the other hand, which partition (90) is located in the machine housing (11) in particular and separates the forced rotation guide (54) or the freewheel device (62) or the drive motor (30) from a dust-laden area or extraction chamber (96) of the hand-held power tool, wherein the dust is generated by the disc tool (14) during the operation of the hand-held power tool, wherein it is advantageously provided that the partition (90) is at least partially or completely provided or represented by the fan wheel (39), and / or in that a seal (92), in particular a labyrinth seal, is provided between an edge region of the fan wheel (39) and the machine housing (11).

15. Hand-held power tool according to any of the preceding claims, characterised in that it has an air ducting assembly for guiding a cooling air flow (K) past the forced rotation guide (54) and / or the freewheel device (62) and / or the drive motor (30) towards the tool holder (51), and / or in that the machine housing (11) has at least one inflow opening (97) in a region averted from the tool holder (51), in particular at a handle section (12), through a cooling air flow (K) flows into the machine housing (11) during the operation of the hand-held power tool, flowing past the forced rotation guide (54) and / or the freewheel device (62) and / or the drive motor (30) and in particular flowing out of the machine housing (11) via at least one outflow opening (98) of the machine housing (11).