Handheld machine tools

Abstract

This invention provides a handheld machine tool with enhanced robustness in the tool holder. [Solution] A handheld machine tool (100) is disclosed, comprising a housing (110), a drive unit (111), a striking mechanism (122) drivable by the drive unit (111), and a tool holder (150) for holding a mounted tool, wherein the tool holder (150) is at least partially drivable by the striking mechanism (122). It is proposed that the handheld machine tool (100) has a spacer element formed to separate the mounted tool from the housing (110).

Description

Technical Field

[0001] The present invention relates to a hand-held power tool in the form described in the superordinate concept of claim 1.

[0002] Background Art There is already known a hand-held power tool having a drive unit, a housing, a striking mechanism, and a tool holder.

[0003] Disclosure of the Invention The present invention starts from a hand-held power tool having a housing, a drive unit, a striking mechanism drivable by the drive unit, and a tool holder for holding a mounting tool, the tool holder being at least partially drivable by the striking mechanism. It is proposed that the hand-held power tool has a spacer element formed to space the mounting tool from the housing.

[0004] The present invention provides a hand-held power tool in which the robustness of the tool holder is enhanced. The tool holder in a hand-held power tool is a location that is prone to defects, particularly breakage, when a high load is applied. Depending on the mounting tool used, it may happen that the mounting tool slides around during operation of the tool holder. As a result, on the one hand, optimal torque transmission from the striking mechanism is not achieved, and on the other hand, a non-uniform load on the tool holder occurs. As a result, in this case, there is a risk of continuously occurring peak loads that lead to defects or breakage of the tool holder. The present invention solves such problems.

[0005] The hand-held power tool may be formed as an electrically operated hand-held power tool. In this case, the electrically operated hand-held power tool may be formed as a mains-operated hand-held power tool or as a rechargeable battery-operated hand-held power tool. For example, the hand-held power tool may be formed as a driver, a drill driver, an impact driver, a hammer, a drill hammer or an impact drill driver.

[0006] The housing of a handheld machine tool is formed to accommodate, at least partially, the drive unit, the striking mechanism, and the tool holder. The housing may be formed as a shell housing with two half-shells.

[0007] A handheld machine tool has a drive unit. The drive unit includes a drive motor and a transmission. The drive motor may be an electrically rectified drive motor. In particular, the drive motor may be formed as at least one electric motor. The transmission may be formed as at least one planetary gear transmission, which may be switchable, for example. The drive motor is formed to be operable by a manual switch. When the manual switch is operated by the user, the drive motor is turned on and the handheld machine tool is operated. When the manual switch is not operated further by the user, the drive motor is turned off. Preferably, the drive motor is electronically open-loop controllable and / or closed-loop controllable, thereby enabling a reverse rotation mode and setting of a desired rotation speed. In reverse rotation mode, the drive motor may be switchable between clockwise and counterclockwise rotation. To switch the drive motor in reverse rotation mode, the handheld machine tool may have a rotation direction switching element, in particular a rotation direction switching switch.

[0008] Handheld machine tools have a striking mechanism. The striking mechanism generates a high torque peak during operation, thereby disengaging, attaching, or drilling a fixed coupling. The striking mechanism can be connected to a drive motor by a transmission. The striking mechanism can be formed, for example, as a rotary striking mechanism, a locking striking mechanism, a rotational striking mechanism, a V-groove striking mechanism, or a hammer striking mechanism. The transmission and / or striking mechanism may have an intermediate shaft. For example, the intermediate shaft may hold the planetary gears of the transmission. Furthermore, the intermediate shaft may at least partially drive the striking mechanism. The striking mechanism may have a striking mechanism housing and / or a striking mechanism cover. Furthermore, the striking mechanism may have at least one striking body or hammer and at least one striking mechanism spring. In this case, the striking body and the striking mechanism spring may be substantially located inside the striking mechanism housing. The striking body includes at least one striking projection. For example, two or three striking projections may be provided. The striking mechanism spring may be formed as, for example, a coil spring, a barrel spring, a cone spring, a chimney spring, or a non-conformed spring.

[0009] A handheld machine tool has a tool holder. The tool holder may be formed as an internal tool holder, such as a bit holder, and / or an external tool holder, such as a nut holder. The tool holder can hold mounting tools, such as screwdriver bits, socket wrenches, or sockets, so that the user can screw-connect the fixed elements to a fixed support. A striking mechanism is formed to drive a driven shaft. The driven shaft is formed to drive the tool holder. The tool holder has at least one anvil projection at its end in the direction of the striking mechanism and / or drive unit. The striking body of the striking mechanism is formed to rotate the anvil projection circumferentially by the striking projection and, in this case, to drive the tool holder. For example, the tool holder may have two or three anvil projections.

[0010] Additionally, the handheld machine tool includes an energy supply unit, which is provided for battery operation, particularly by a handheld machine tool battery pack, and / or for network operation. In a preferred embodiment, the energy supply unit for battery operation is formed. Within the scope of the present invention, “handheld machine tool battery pack” should be understood as a combination of at least one battery cell and a battery pack housing. The handheld machine tool battery pack is advantageously formed to supply energy to a commercially available battery-operated handheld machine tool. At least one battery cell may be formed as a lithium-ion battery cell having a nominal voltage of, for example, 3.6V. For example, the handheld machine tool battery pack may contain up to 10 battery cells, in which case other numbers of battery cells are also possible. Both embodiments as battery-operated handheld machine tools and operation as network-operated handheld machine tools are well known to those skilled in the art, so details of the energy supply will not be mentioned here.

[0011] A handheld machine tool may have at least a control unit for controlling the drive unit. The control unit may be located within the housing, for example, in the handgrip of the handheld machine tool, or in the area of ​​the energy supply interface.

[0012] A spacer element is formed to separate the mounting tool from the housing. In this case, the spacer element separates the mounting tool so that it is separated from the housing while coupled to the tool holder and does not substantially come into contact with the housing during operation of the handheld machine tool. The spacer element is formed, for example, as a spacer. The spacer element may be formed, for example, as a ring, disc, or plate.

[0013] In embodiments of handheld machine tools, the spacer element can be attached to the tool holder. The spacer element may be attached in such a way that the tool holder can be used without being substantially obstructed when the spacer element is in use. The spacer element may be coupled to the tool holder, for example, by form connection and / or friction connection.

[0014] According to an embodiment of a handheld machine tool, the spacer element has a holding portion for the tool holder. The holding portion for the tool holder may have an inner holding portion for the tool holder. The inner holding portion for the tool holder may have a shape corresponding to the tool holder. By positioning the spacer element on the tool holder using the inner holding portion of the spacer element, optimal torque transmission from the tool holder to the mounted tool becomes possible.

[0015] In embodiments of handheld machine tools, the tool holder has a transition section, the transition section of which a spacer element holder is located. The spacer element holder is formed so as to hold the transition section. The spacer element holder and the transition section are formed to correspond to each other. In this case, the inner holder of the spacer element is formed to correspond to the transition section. The tool holder additionally has a torque transmission section or a drive section. The torque transmission section is formed to transmit torque to the mounted tool. The torque transmission section may be formed in a polygonal shape, such as a square. For example, the torque transmission section may be formed in a substantially cubic shape. Furthermore, the tool holder may have a driven section. The driven section may be terminated by an anvil projection. The driven section may be formed in a cylindrical shape, for example. The driven section is formed to transmit the rotational motion absorbed by the anvil projection to the transition section. The transition section may be located between the torque transmission section and the driven section.

[0016] In the handheld machine tool embodiment, the transition section has a radius in the range of 3 mm to 8 mm. This radius is optimized and formed to enhance the stability and robustness of the transition section. Preferably, this radius is formed in the range of 5 mm to 7 mm.

[0017] In embodiments of handheld machine tools, the spacer element holder has a polygonal portion. The polygonal portion of the spacer element holder is polygonal and is formed to correspond to the torque transmission portion. In this case, the polygonal portion allows the spacer element to contact the tool holder, at least in shape, and particularly at least partially, the torque transmission portion. The polygonal portion may be formed, for example, in the form of a cube, a hollow cube, a rectangular parallelepiped, or a hollow rectangular parallelepiped. The polygonal portion may be formed in a direction toward the tool holder or the mounted tool.

[0018] In embodiments of handheld machine tools, the spacer element holder has a cylindrical portion. The cylindrical portion of the spacer element holder is formed to correspond to the driven portion. The cylindrical portion allows the spacer element to contact the tool holder at least by shape connection. The cylindrical portion may be formed in the direction of the drive unit.

[0019] In embodiments of handheld machine tools, the spacer element has a contact element formed to hold the mounted tool. The contact element may be formed, for example, as the contact surface of the spacer element. When the mounted tool is coupled to the tool holder, the contact element may be positioned away from the drive unit. The contact element may be coupled to the spacer element. The contact element and the spacer element can be integrated. The spacer element and the contact element may be formed from an elastic material. Both the contact element and the spacer element can function to dampen vibrations during the operation of the handheld machine tool. The contact element may be formed, for example, in the shape of a disc or a ring.

[0020] In embodiments of handheld machine tools, the spacer element can be positioned in the tool holder at a distance from the housing and / or the striking mechanism housing. The spacer element may be positioned in the tool holder at a distance from the housing and / or the striking mechanism housing so that it does not come into contact with the housing when the handheld machine tool, particularly the tool holder, is in operation.

[0021] The present invention also originates from the spacer element for the handheld machine tool described above according to any one of claims 1 to 9.

[0022] The present invention will be described below in terms of preferred embodiments. [Brief explanation of the drawing]

[0023] [Figure 1] This is a schematic diagram showing a handheld machine tool according to the present invention. [Figure 2a] This is a side view showing a handheld machine tool along with a spacer element. [Figure 2b] This is a side view showing a handheld machine tool with coupled spacer elements. [Figure 3]This figure shows a portion of a longitudinal cross-sectional view of the tool holder section of a handheld machine tool equipped with coupled spacer elements.

[0024] Description of the Examples Figure 1 shows a handheld machine tool 100 according to the present invention, which is formed, for example, as a rechargeable battery-powered impact driver 100. The handheld machine tool 100 includes a tool holder 150. The handheld machine tool 100 has a housing 110 equipped with a handgrip 126. The handheld machine tool 100 is configured as a rechargeable battery-powered handheld machine tool 100, as it can be mechanically and electrically connected to an energy supply unit for battery operation for power supply independent of the power grid. In this case, a handheld machine tool battery pack 130 is used as the energy supply unit. However, the present invention is not limited to rechargeable battery-powered handheld machine tools, but can also be applied to handheld machine tools that depend on the power grid, i.e., power grid-powered handheld machine tools.

[0025] The housing 110 in this case includes a drive unit 111. The drive unit 111 is located within the housing 110. The drive unit 111 includes an electrically rectified drive motor 114, powered by a handheld machine tool battery pack 130, and a transmission 118. The transmission 118 is formed as at least one planetary gear transmission. The drive motor 114 is operable, for example, via a manual switch 128, which is designed to allow the drive motor 114 to be switched on and off. Advantageously, the drive motor 114 is electronically open-loop controllable and / or closed-loop controllable, which enables a reverse rotation mode, as well as a desired rotation speed. For the reverse rotation mode, the handheld machine tool 100 has a rotation direction switching element 121, which is formed as a rotation direction switching switch. The rotation direction switching element 121 is formed to switch the drive motor 114 between clockwise and counterclockwise rotation. The appropriate structure and functional form of a drive motor are well known to those skilled in the art and will not be discussed in detail here.

[0026] The housing 110 at least partially houses the drive motor 114, the transmission 118, and the tool holder 150. In this embodiment, the housing 110 is shaped as a shell housing having two half shells 112.

[0027] The handheld power tool 100, which is formed as a rechargeable battery-powered impact driver, includes a striking mechanism 122 with an intermediate shaft 120, particularly a rotary striking mechanism 122. Both the rotary striking mechanism 122 and the intermediate shaft 120 are disposed within the housing 110. The rotary striking mechanism 122 includes a striking mechanism housing 123. In this case, the rotary striking mechanism 122 may be disposed within another suitable housing, such as a transmission housing 119 for example. The rotary striking mechanism 122 includes a striking body and a striking mechanism spring, although in this case, the striking body and the striking mechanism spring are not shown in detail. The striking body and the striking mechanism spring are substantially disposed within the striking mechanism housing 123. The striking body has two striking protrusions, which are not shown in detail. The rotary striking mechanism 122 is formed to drive a driven shaft 124. The handheld power tool 100 has a tool axis 102. In this case, the rotational axis of the driven shaft 124 forms the tool axis 102. The driven shaft 124 is provided to drive a tool holder 150. The tool holder 150 is provided on the driven shaft 124. Preferably, the tool holder 150 is integrally formed on and / or formed on the driven shaft 124. Preferably, the tool holder 150 is disposed in the axial direction 132 opposite to the drive unit 111. The tool holder 150 or the driven shaft 124 has two anvil protrusions 164 at the end in the direction of the rotary striking mechanism 122 and / or the drive unit 111. Refer also to FIG. 3. The striking body of the rotary striking mechanism 122 rotates the anvil protrusions circumferentially by the striking protrusions and is provided to drive the tool holder 150 or the driven shaft 124 in this case. The tool holder 150 is formed as a tool outer holder 152, such as a nut holder for example. The tool holder 150 is formed to hold a mounting tool 140, such as a socket wrench or a socket for example.

[0028] The handheld power tool 100 has a control unit 170 for controlling at least the drive unit 111, particularly the drive motor 114. The housing 110 at least partially houses the control unit 170.

[0029] Furthermore, the housing 110 includes an energy supply unit holder 160. The energy supply unit holder 160 houses a handheld machine tool battery pack 130, in which case it forms mounting legs 162 with mounting surfaces. The handheld machine tool battery pack 130 can be removed from the energy supply unit holder 160 without the use of tools. In addition, the housing 110 has a handgrip 126 and the energy supply unit holder 160. The user can grip the handgrip 126. In the embodiment, the energy supply unit holder 160 is positioned on the handgrip 126. The mounting legs 162 allow the handheld machine tool 100 to be placed.

[0030] Figure 2 shows a side view 300 of a handheld machine tool 100. In this case, Figure 2a shows a side view 300 including a spacer element 200. Figure 2b shows a side view 300 of the handheld machine tool 100 with the coupled spacer element 200. The handheld machine tool 100 includes a spacer element 200. The spacer element is provided to separate the mounting tool 140 from the housing. The spacer element 200 separates the mounting tool 140 so that the mounting tool 140 is separated from the housing 110 while coupled to the tool holder 150, and does not substantially contact the housing at least during the operation of the handheld machine tool 100. For example, in this case, the spacer element 200 is molded as a ring-shaped spacer. The spacer element 200 is attachable to the tool holder 150. In this case, the spacer element 200 is connectable to the tool holder 150 at least by shape connection. The spacer element 200 includes a retaining portion 210 for the tool retaining portion 150, which is formed as an inner retaining portion 212 for the tool retaining portion 150. In this case, the inner retaining portion 212 for the tool retaining portion 150 has a shape corresponding to the tool retaining portion 150.

[0031] The tool holder 150 includes a transition section 230. The spacer element 200 holder 210 is configurable on the transition section 230, and the spacer element 200 holder 210 is molded so that it holds the transition section 230. Furthermore, the spacer element 200 holder 210 and the transition section 230 are molded to correspond to each other. The tool holder 150 includes a torque transmission section 240 or a drive section. The torque transmission section 240 is provided to transmit torque to the mounted tool 150. In this case, the torque transmission section is molded, for example, as a polygon such as a square, and is substantially molded as a cube. The tool holder 150 includes a driven section 250. The driven section 250 is terminated by an anvil projection 164, see also Figure 3. In this case, the driven section 250 is molded, for example, as a cylinder. The transition section 230 is positioned between the torque transmission section 240 and the driven section 250. The transition section 240 has a radius 232 in the range of 3 mm to 8 mm.

[0032] The spacer element 200 includes a contact element 220. The contact element 220 is provided to hold the mounting tool 150, so that the mounting tool 150 is in contact with the contact element 220 during operation of the handheld machine tool 100. In this case, the contact element 220 is formed, for example, as a contact surface 222. When the mounting tool 140 is coupled to the tool holder 150, the contact element 220 is positioned away from the drive unit 111. The spacer element 200 and the contact element 220 are integral in this case, as they form the contact element 220. The spacer element 200 and the contact element 220 are manufactured from an elastic material in this case. The contact element 220 is formed, for example, as a disc. The spacer element 200 can be positioned in the tool holder 150, spaced apart from the housing 110 and / or the striking mechanism housing 123.

[0033] Figure 3 shows a portion 310 of a longitudinal cross-sectional view of the tool holder of a handheld machine tool 100 equipped with a coupled spacer element 200. The holder 210 of the spacer element 200 includes a polygonal portion 214. In this case, the polygonal portion 214 of the holder 210 of the spacer element 200 is polygonal and molded to correspond to the torque transmission portion 240. In the coupled state, the polygonal portion 214 at least partially contacts the torque transmission portion 240 in a shape connection manner. For example, the polygonal portion 214 is molded in the form of a hollow cube and is molded in a direction toward the tool holder 150 or the mounted tool 140. The holder 210 of the spacer element 200 includes a cylindrical portion 216. The cylindrical portion 216 of the holder 210 of the spacer element 200 is molded to correspond to the driven portion 250. In this case, the cylindrical portion 214 allows the spacer element 200 to contact the driven portion 250 of the tool holding portion 150, at least in a shape-connected manner. In this case, the cylindrical portion 216 is molded in the direction of the drive unit 111.

Claims

1. A handheld machine tool (100) comprising a housing (110), a drive unit (111), a striking mechanism (122) drivable by the drive unit (111), and a tool holder (150) for holding a mounting tool (140), wherein the tool holder (150) is at least partially drivable by the striking mechanism (122), A handheld machine tool (100) is provided with a spacer element (200) formed to separate the mounting tool (140) from the housing (110).

2. The handheld machine tool (100) according to claim 1, characterized in that the spacer element (200) can be attached to the tool holding part (150).

3. The handheld machine tool (100) according to claim 1 or 2, characterized in that the spacer element (200) has a holding portion (210) for the tool holding portion (150).

4. The handheld machine tool (100) according to claim 3, characterized in that the tool holding portion (150) has a transition portion (230), and the holding portion (210) of the spacer element (200) can be positioned on the transition portion (230).

5. The handheld machine tool (100) according to claim 4, characterized in that the transition section (230) has a radius (232) in the range of 3 mm to 8 mm.

6. The handheld machine tool (100) according to any one of claims 2 to 5, characterized in that the holding portion (210) of the spacer element (200) has a polygonal portion (214).

7. The handheld machine tool (100) according to any one of claims 2 to 6, characterized in that the holding portion (210) of the spacer element (200) has a cylindrical portion (216).

8. The handheld machine tool (100) according to any one of claims 1 to 7, characterized in that the spacer element (200) has a contact element (220) formed to hold the mounting tool (140).

9. The handheld machine tool (100) according to any one of claims 1 to 8, characterized in that the spacer element (200) is spaced apart from the housing (110) and / or the striking mechanism housing (123) and can be positioned in the tool holding portion (150).

10. A spacer element (200) for a handheld machine tool (100) according to any one of claims 1 to 9.

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