hand-held power tool with a planetary gearbox

Abstract

In a hand-held power tool with a tool holder and a housing in which a planetary gear (120) with at least a first planetary stage (202) and a second planetary stage (203) for driving the tool holder is arranged, and a drive motor (180) with a drive shaft (215) for driving the planetary gear (120), the first planetary stage (202) has at least three planet gears (233, 234) which are connected to each other via a carrier ring (263), wherein the carrier ring (263) is arranged in a ring gear (251) of the planetary gear (120).

Description

State of the art

[0001] The present invention relates to a hand-held power tool with a tool holder and a housing in which a planetary gear with at least a first planetary stage and a second planetary stage for driving the tool holder, as well as a drive motor with a drive shaft for driving the planetary gear are arranged.

[0002] Such a handheld power tool is known from the prior art, comprising a tool holder and a housing in which a planetary gear is arranged. The planetary gear has a first and a second planetary stage for driving the tool holder. Furthermore, a drive motor with a drive shaft for driving the planetary gear is provided. Disclosure of the invention

[0003] The invention relates to a handheld power tool with a tool holder and a housing in which a planetary gear with at least a first planetary stage and a second planetary stage for driving the tool holder is arranged, as well as a drive motor with a drive shaft for driving the planetary gear. The first planetary stage has at least three planetary gears connected to one another via a carrier ring, wherein the carrier ring is arranged in a ring gear of the planetary gear.

[0004] The invention thus makes it possible to provide a robust and compact hand-held power tool.

[0005] Preferably, the at least three planetary gears are connected to one another via a further carrier ring which is arranged in a transmission housing assigned to the first planetary stage in a rotatable manner, in particular in a receptacle of the transmission housing.

[0006] This enables a safe and stable arrangement of the planetary gears.

[0007] Preferably, at least the first planetary stage is arranged in the transmission housing.

[0008] This allows for a simple and uncomplicated arrangement of the first planetary stage.

[0009] According to one embodiment, the transmission housing has a receptacle for receiving a bearing element, wherein the bearing element is designed to support the drive shaft, which has an axis of rotation, and wherein the bearing element is arranged perpendicular to the axis of rotation within the first and / or second carrier ring.

[0010] This enables a safe and robust mounting of the drive shaft.

[0011] Preferably, the bearing element is arranged along the axis of rotation within the gear housing.

[0012] This makes it easy to create a compact arrangement.

[0013] According to one embodiment, a ring gear assigned to the first planetary stage and a sun gear provided for driving the second planetary stage are formed in one piece.

[0014] This makes it easy and straightforward to reduce the installation space required to construct the planetary gear.

[0015] Preferably, the ring gear and the sun gear have a common axis of rotation and are connected to each other via webs aligned perpendicular to the axis of rotation.

[0016] This enables a robust and stable connection between the ring gear and the sun gear.

[0017] The ring gear preferably has an internal toothing and is arranged rotatably in the housing.

[0018] This allows for a simple and uncomplicated arrangement of the ring gear in the housing.

[0019] Preferably, the first planetary stage is assigned a ring gear arranged in the housing in a rotationally fixed manner, wherein the at least three planetary gears each have a first gear section which is operatively connected to the rotationally fixed ring gear, and each have a second gear section which is operatively connected to the ring gear.

[0020] This makes it easy to transmit rotation from the drive motor to the planetary gear.

[0021] Preferably, the first gear section and the second gear section have different diameters.

[0022] This makes it easy and straightforward to provide compact planetary gears with reduced longitudinal dimensions.

[0023] According to one embodiment, an output shaft that can be driven by the planetary gear can be arranged in sections within the planetary gear in an operating mode of the hand-held power tool, in particular a hammer mode or an impact drilling mode.

[0024] This enables further compaction of the hand tool.

[0025] Preferably, the output shaft can be arranged in sections in an internal receptacle of a sun gear or ring gear of the planetary gear arranged facing the output shaft.

[0026] This enables a safe and reliable section-wise arrangement of the output shaft in the planetary gear. Short description of the drawings

[0027] The invention is explained in more detail in the following description using exemplary embodiments illustrated in the drawings. They show: Fig. 1 a schematic view of a hand-held power tool with a drive motor and a planetary gear, Fig. 2 a longitudinal section through the drive motor and the planetary gear of Fig. 1, Fig. 3 is an exploded perspective view of a planetary gear of Fig. 2 assigned planetary stage, Fig. 4 a perspective view of one of the planetary stages of Fig. 2 and Fig. 3 assigned transmission component, Fig. 5 a longitudinal section through the first planetary stage of Fig. 2 to Fig. 4, Fig. 6 a longitudinal section through an alternative planetary stage of the planetary gear of Fig. 1 in a first position of the output shaft, and Fig. 7 a longitudinal section through the alternative planetary stage of Fig. 6 in another position of the output shaft. Description of the embodiments

[0028] In the figures, elements with the same or comparable function are provided with identical reference symbols and are described in detail only once.

[0029] Fig. 1 shows an exemplary handheld power tool 100 with a housing 105, in which a drive unit for rotating a tool holder 140 is preferably arranged. Illustratively, the handheld power tool 100 can be mechanically and electrically connected to a battery pack 190 for mains-independent power supply; alternatively or additionally, it can also be operated with mains power.

[0030] The tool holder 140 is illustratively designed to receive an insert tool 198 and rotates during operation about an associated rotational axis 199. Illustratively, the tool holder 140 is designed as a drill chuck 145. Alternatively, however, the tool holder 140 can also be designed as a tool attachment that is detachably arranged on the handheld power tool 100. The handheld power tool 100 is designed, for example, as a drill driver, but can also be designed as an impact drill with a percussion mechanism or as a hammer drill.

[0031] In the illustrated embodiment, the drive unit comprises at least one drive motor 180 and a gear unit 120. The drive motor 180 is preferably designed as an electronically commutated motor. The drive motor 180 can preferably be switched on and off via a manual switch 195, wherein the manual switch 195 is illustratively arranged on a handle 115 of the housing 105.

[0032] The gear 120 is designed as a planetary gear, preferably as a switchable planetary gear. Preferably, the planetary gear 120 is mounted in a gear housing (220 in Fig. 2) arranged.

[0033] Furthermore, the handheld power tool 100 optionally has a torque adjustment device with a torque adjustment sleeve 197. Such a torque adjustment device is sufficiently known from the prior art, so that a detailed description of the optional torque adjustment device is omitted here for the sake of brevity.

[0034] Fig. 2 shows the drive motor 180 provided with a drive shaft 215 for driving the planetary gear 120. An optional fan 210 is arranged on a side of the drive motor 180 facing away from the planetary gear 120 or, illustratively, to the left of the drive motor 180.

[0035] The planetary gear 120 is arranged, for example, in a gear housing 220. The gear housing 220 illustratively has three housing sections 221, 222, 223. Here, a housing section 221 is arranged facing the drive motor 180 and a housing section 223 is one of the tool holder 140 of Fig. 1 associated output shaft 240. A housing section 222 is arranged along the rotation axis 199 of Fig. 1, which also forms the axis of rotation of the drive motor 180 and the planetary gear 120, is arranged between the two housing sections 221, 223.

[0036] The planetary gear 120 preferably has at least a first and a second planetary stage 202, 203 for driving the tool holder 140. Three planetary stages 202, 203, 204 are shown illustratively.

[0037] Preferably, a planetary stage has at least three planetary gears, of which Fig. 2, a maximum of two planetary gears are visible and are therefore described further below. Illustratively, the first planetary stage 202 has the planetary gears 233, 234.

[0038] According to one embodiment, the planetary gears 233, 234 are connected to one another via a carrier ring 263. The carrier ring 263 is preferably arranged in a ring gear 251 of the planetary gear 120, in particular the first planetary stage 202. For this purpose, the ring gear 251 has a receptacle 268 in which the carrier ring 263 can be arranged. The ring gear 251 preferably has an internal toothing 253. Furthermore, the ring gear 251 is rotatably arranged in the housing 105, in particular the gear housing 220 or the first housing section 221. At least the first planetary stage 202 is arranged in the housing section 221 of the gear housing 220. Each planetary gear 233, 234 is assigned an axle 262, 261, via which the planetary gears 233, 234 are arranged on the carrier ring 263.

[0039] According to a further embodiment, the planetary gears 233, 234 are connected to one another via a further carrier ring 263. The carrier ring 263 is preferably arranged rotatably in the gear housing 220 assigned to the first planetary stage 202 or in the first housing section 221. For this purpose, the housing section 221 has a receptacle 269.

[0040] Furthermore, the first planetary stage 202 is assigned a ring gear 265 that is non-rotatably arranged in the housing 105, in particular the transmission housing 220 or the first housing section 221. It should be noted that the non-rotatably arranged ring gear 265 can alternatively be formed integrally with the first housing section 221. The planetary gears 233, 234 are also arranged in the ring gear 265 and can roll therein.

[0041] Each of the planetary gears 233, 234 has a first gear section 281 and a second gear section 282. The first gear section 281 is preferably operatively connected to the rotationally fixed ring gear 265, and the second gear section 282 is operatively connected to the ring gear 251. According to one embodiment, the first gear section 281 and the second gear section 282 have different diameters 298, 299. Preferably, a first diameter 298 associated with the first gear section 281 is smaller than a second diameter 299 associated with the second gear section 282.

[0042] The planetary gears 233, 234, in particular their respective second gear section 282, are driven by a sun gear 229 arranged on the drive shaft 215. The second gear sections 282, in turn, drive the ring gear 251 via its internal toothing 253. Furthermore, the planetary gears 233, 234 move with their first gear section 281 along an internal toothing 266 of the fixed ring gear 265.

[0043] According to one embodiment, the ring gear 251 assigned to the first planetary stage 202 and a sun gear 252 provided for driving the second planetary stage 203 are formed in one piece. The ring gear 251 and the sun gear 252 form a transmission component 250. Preferably, the ring gear 251 and the sun gear 252 have the common rotational axis 199. Furthermore, the ring gear 251 and the sun gear 252 are preferably connected via webs (342 in Fig. 3) connected to each other.

[0044] Preferably, at least three planetary gears of the second planetary stage 203 are arranged on an external toothing 254 of the sun gear 252, of which only the planetary gears 235, 236 are visible here. A switching ring gear 276 with a switching wire yoke 278 is illustratively assigned to the planetary gears 235, 236. The second planetary stage 203 is arranged in the second housing section 222. Axles 206, 207 are assigned to the planetary gears 235, 236. A carrier ring 205 is arranged along the rotation axis 199 between the ring gear 251 and the planetary gears 235, 236. The carrier ring 205 supports the axes 206, 207 of the planetary gears 235, 236. A carrier ring 272 is preferably arranged on a side of the planetary gears 235, 236 facing the output shaft 240. The carrier ring 272 also supports the axes 206, 207.

[0045] Furthermore, a sun gear 271 of the third planetary stage 204 is illustratively assigned to the carrier ring 272. According to one embodiment, the carrier ring 272 and the sun gear 271 are formed integrally. Planetary gears 237, 238 are in turn assigned to the sun gear 271. The planetary gears 237, 238 are, for example, operatively connected to a switching ring gear 275 with a switching wire yoke 277. Furthermore, a driver 273 is preferably provided, which transmits a rotational movement of the third planetary stage 204 to the output shaft 240.

[0046] The sun gears 252, 271 preferably have an internal receptacle 255, 274, each of which has a larger diameter than the output shaft 240. The output shaft 240 is mounted, for example, via an internal receptacle 212 of the driver 273 and via a bearing element 232 in the third housing section 223. For this purpose, the third housing section 223 preferably has a bearing receptacle 225.

[0047] According to one embodiment, the output shaft 240 driven by the planetary gear 120 can be arranged along the rotational axis 199 of the drive motor 180 in an operating mode of the hand-held power tool 100, in particular a hammer mode or a percussion drilling mode, in sections within the planetary gear 120. In this case, an end face 283 of the output shaft 240 is arranged spaced apart from an end face 211 of the driver 273 in the direction of the drive motor 180. In this case, the output shaft 240 is preferably arranged in the inner receptacle 274 of the sun gear 271 or a ring gear (630 in Fig. 6) of the planetary gear 120.

[0048] At an end of the gear housing 220 facing the drive motor 180, a bearing element 231 is illustratively arranged. The bearing element 231 is arranged, for example, in a receptacle 224 of the first housing section 221. In this case, the bearing element 231 is designed to support the drive shaft 215. Preferably, the receptacle 224 of the bearing element 231 is perpendicular to the rotation axis 199 within the first and / or second carrier ring 263 (320 in Fig. 3). Furthermore, the bearing element 231 is preferably arranged along the rotation axis 199 within the gear housing 220 or the first housing section 221.

[0049] Fig. 3 shows the exemplary first planetary stage 202 of Fig. 2. This illustrates Fig. 3 which is non-rotatably mounted in the gearbox housing 220 of Fig. 2 arranged ring gear 265, which illustratively has anti-rotation elements 311 on its outer circumference. The anti-rotation elements 311 are preferably designed as circumferential extensions and, for example, in associated receptacles of the gear housing 220 of Fig. 2. Illustratively, four anti-rotation elements 311 are shown, with a gap 312 being formed in the circumferential direction between each two adjacent anti-rotation elements 311.

[0050] Furthermore, Fig. 3 the planetary gears 233, 234 of Fig. 2 with its first and second gear sections 281, 282 and the axes 261, 262 for mounting on the carrier ring 263 or a carrier ring 320. Illustratively, the carrier ring 320 is arranged facing the ring gear 265 and the carrier ring 263 is connected to the transmission component 250 of Fig. 2 arranged facing each other.

[0051] In addition, Fig. 3 the gear component 250 with the ring gear 251 and the sun gear 252. The ring gear 251 and the sun gear 252 are preferably perpendicular to the rotation axis 199 (see Fig. 1 and Fig. 2) or in the radial direction 301 are connected to one another by webs 342. Illustratively, the transmission component 250 has four webs 342. It should be noted that the transmission component 250 can also have fewer or more than four webs 342.

[0052] Fig. 4 shows the transmission component 250 of Fig. 2 and Fig. 3 with the ring gear 251 and the sun gear 252. Fig. 4 the webs 342 and the receptacle 268 for receiving the carrier ring 263 of Fig. 2 and Fig. 3.

[0053] Fig. 5 shows the exemplary first planetary stage 202 of Fig. 2 and Fig. 3 with the transmission component 250 of Fig. 2 to Fig. 4. Here, the carrier ring 263 is arranged in the receptacle 268 of the transmission component 250. The carrier ring 320 is arranged illustratively to the left of the ring gear 265. Furthermore, Fig. 5 the first diameter 298 associated with the first gear section 281, which is smaller than the second diameter 299 associated with the second gear section 282.

[0054] Fig. Figure 6 shows an alternative planetary stage 602 with ring gears 640, 630 and planet gears 637, 638, each arranged on a carrier ring 650 via an axle 661, 662. The planet gears 637, 638 are driven by a central sun gear 660.

[0055] The planetary gears 637, 638 illustratively have a first tooth portion 681 with a first diameter 699 and a second tooth portion 682 with a second diameter 698. The first diameter 699 is preferably larger than the second diameter 698. Compared to the embodiment of Fig. 2 to Fig. 5, the first tooth portion 681 with the first diameter 699 is arranged facing away from the output shaft 240 and the second tooth portion 682 with the second diameter 698 is arranged facing the output shaft 240.

[0056] Furthermore, the ring gear 640, which meshes with the first toothed section 681 via its internal toothing 641, is arranged facing away from the output shaft 240. The ring gear 630 meshes with the second toothed section 682 via its internal toothing 631 and is arranged facing the output shaft 240. Preferably, the ring gear 630 is formed integrally with the driver 273.

[0057] Analogous to the embodiment of Fig. 2 to Fig. 5, the output shaft 240 is mounted on the bearing element 232 and the driver 273. In the Fig. 6, the end face 283 of the output shaft 240 and the end face 211 of the driver 273 are illustratively located on a common cross-sectional line 601. The ring gear 630 has an internal receptacle 674 in which the output shaft 240 can preferably be arranged in sections. In Fig. 6, the output shaft 240 is not arranged in the internal receptacle 674.

[0058] Fig. 7 shows the planetary stage 602 of Fig. 6 in a hammer mode or a percussion drilling mode, in which the output shaft 240 is partially within the planetary gear 120 of Fig. 1 and Fig.2, or the planetary stage 602. In particular, the output shaft 240 is arranged in sections in the inner receptacle 674 of the ring gear 630. In this case, the end face 283 of the output shaft 240 is arranged, illustratively, offset by a distance 703 from the end face 211 of the driver 273 toward the ring gear 640.

[0059] Furthermore, the end face 283 of the output shaft 240 is arranged, for example, in a longitudinal direction 701 of the planetary stage 602 within the ring gear 630. Furthermore, the end face 283 of the output shaft 240 is preferably arranged coaxially with the planetary gears 637, 638, in particular the toothed portions 682.

Claims

[1] Hand-held power tool (100) with a tool holder (140) and a housing (105) in which a planetary gear (120) with at least a first planetary stage (202) and a second planetary stage (203) for driving the tool holder (140) is arranged, and a drive motor (180) with a drive shaft (215) for driving the planetary gear (120), characterized by that the first planetary stage (202) has at least three planetary gears (233, 234) which are connected to one another via a carrier ring (263), wherein the carrier ring (263) is arranged in a ring gear (251) of the planetary gear (120). [2] Hand tool according to claim 1, characterized by that the at least three planetary gears (233, 234) are connected to one another via a further carrier ring (263) which is arranged such that it can rotate in a gear housing (221) assigned to the first planetary stage (202), in particular in a receptacle (269) of the gear housing (221). [3] Hand tool according to claim 1 or 2, characterized by that at least the first planetary stage (202) is arranged in the gear housing (221). [4] Hand tool according to one of claims 2 or 3, characterized by in that the gear housing (221) has a receptacle (224) for receiving a bearing element (231), wherein the bearing element (231) is designed to support the drive shaft (215) which has an axis of rotation (199), and wherein the bearing element (231) is arranged perpendicular to the axis of rotation (199) within the first and / or second carrier ring (263; 320). [5] Hand tool according to claim 4, characterized by that the bearing element (231) is arranged along the rotation axis (199) within the gear housing (221). [6] Hand tool according to one of the preceding claims, characterized bythat a ring gear (251) assigned to the first planetary stage (202) and a sun gear (252) provided for driving the second planetary stage (203) are formed in one piece. [7] Hand tool according to claim 6, characterized by that the ring gear (251) and the sun gear (252) have a common axis of rotation (199) and are connected to one another via webs (342) aligned perpendicular to the axis of rotation (199). [8] Hand tool according to claim 6 or 7, characterized by that the ring gear (251) has an internal toothing (253) and is arranged rotatably in the housing (105). [9] Hand tool according to one of the preceding claims, characterized byin that the first planetary stage (202) is assigned a ring gear (265) arranged in a rotationally fixed manner in the housing (105), wherein the at least three planetary gears (233, 234) each have a first gear section (281) which is operatively connected to the rotationally fixed ring gear (265), and each have a second gear section (282) which is operatively connected to the ring gear (251). [10] Hand tool according to claim 9, characterized by that the first gear section (281; 681) and the second gear section (282; 682) have different diameters (298, 299; 698, 699). [11] Hand tool according to one of the preceding claims, characterized by that an output shaft (240) drivable by the planetary gear (120) can be arranged in sections within the planetary gear (120) in an operating mode of the hand-held power tool (100), in particular a hammer mode or an impact drilling mode. [12] Hand tool according to claim 11, characterized by that the output shaft (240) can be arranged in sections in an internal receptacle (274; 674) of a sun gear (271) or ring gear (630) of the planetary gear (120) arranged facing the output shaft (240).

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