drive device

Abstract

The present invention relates to a drive mechanism for a vehicle (100), which is particularly operable by muscle force and / or motor power, comprising: a housing (1); a drive unit within the housing; a frame interface (2); and a screw (3), wherein the housing and the frame interface are screwed together along a helical axis (30) by means of the screw, the housing is partially coated with a coating (7) such that, when the housing and the frame interface are screwed together, at least a portion of the coating is disposed between the housing and the frame interface, the frame interface having a predetermined surface structure (4) designed to plastically deform a region of the housing during initial screwing with at least one predetermined preload (5), such that the surface structure and the plastically deformed region form a shape fit in a plane (35) perpendicular to the helical axis, and the region to be plastically deformed is formed without coating.

Description

Technical Field

[0001] The present invention relates to a drive device, a vehicle including the drive device, and a method for manufacturing the drive device for the vehicle. Background Technology

[0002] For example, the drive unit of an electric bicycle is known, in which the drive unit is screwed onto the vehicle's frame via a mounting plate for secure mounting. To achieve precise alignment of the drive unit relative to the vehicle frame, a special gauge is often used for positioning during the initial tightening. If the drive unit later needs to be removed from the vehicle frame, for example for maintenance or repair, reinstallation requires realigning it again using a special gauge to regain the precise relative alignment. Similarly, a special gauge may be needed for precise relative mounting of the mounting plate and drive unit. Summary of the Invention

[0003] In contrast, the present invention provides a drive mechanism for a vehicle, particularly one operable by muscle force and / or motor power, the drive mechanism comprising: a housing, a drive unit within the housing, a frame interface, and screws, wherein the housing and the frame interface are screwed together along a helical axis by means of the screws, the housing is partially coated such that at least a portion of the coating is disposed between the housing and the frame interface when the housing and the frame interface are screwed together, the frame interface having a predetermined surface structure designed to plastically deform a region of the housing with at least one predetermined preload during the initial screwing of the housing and the frame interface, such that the surface structure and the plastically deformed region form a shape fit in a plane perpendicular to the helical axis, and the region to be plastically deformed is formed without coating.

[0004] The advantage of the drive mechanism according to the invention is that, through a particularly simple and cost-effective design, the drive unit can be easily and accurately re-screwed onto the frame interface. Furthermore, a particularly robust and reliable fixation of the drive unit can be achieved. This is achieved by a vehicle drive mechanism comprising a housing, a drive unit disposed within the housing, a frame interface, and screws. The housing and frame interface are screwed together along a helical axis. The housing is at least partially coated such that, when the housing and frame interface are threaded together, at least a portion of the coating is disposed between the housing and the frame interface. The frame interface has a predetermined surface structure designed to plastically deform a region of the housing with at least one predetermined preload during the initial screwing of the frame interface and the housing. The surface structure is configured to deform the region such that the surface structure and the plastically deformed region form a form fit in a plane perpendicular to the helical axis. The region of the housing to be plastically deformed is here formed without a coating. Form fit here is considered as at least partial engagement of the surface structure and the plastically deformed region in a plane perpendicular to the helical axis.

[0005] In other words, the drive unit comprises two components that can be screwed together, namely a housing and a frame interface, wherein the frame interface has a predetermined surface structure, and the housing has a region of plastic deformation in a predetermined manner, which is generated by the back pressure on the surface structure during initial tightening. The surface structure and the plastically deformed region engage with each other, thereby forming a form fit in a plane perpendicular to the helical axis.

[0006] The drive unit preferably includes a motor and / or a gear mechanism. The frame interface can be configured as needed. For example, the frame interface can be a portion of the vehicle frame. An alternative preferred option is that the frame interface is a mounting plate, preferably configured for screwing onto the vehicle frame, particularly by means of a separate threaded connection.

[0007] Surface structures can be specifically considered as bulges and / or depressions on the surface of the corresponding element. For example, a bulge as a surface structure can lead to a corresponding depression in the housing. In particular, a depression can cause plastic flow in the deformable region of the housing, thereby enabling a bulge that at least partially corresponds to the depression to be realized in the housing.

[0008] The advantage of this drive mechanism is that the relative arrangement of the drive unit and the frame interface can be reproduced in a particularly simple way, for example, after loosening the threaded connection when removing the drive unit. This relative arrangement is defined during initial tightening, particularly relative to a plane perpendicular to the helical axis. At this point, the area of ​​plastic deformation in the housing, generated during initial tightening by means of the surface structure, defines the relative position of the housing and frame interfaces relative to each other. That is, when the housing and frame interfaces are loosened after the first disassembly and are intended to be tightened together again, they simply find their previously defined relative positions again based on the surface structure and the resulting predetermined plastic deformation. This allows for particularly simple and rapid reassembly of the drive mechanism, especially without the need for special gauges for precise relative positioning during reassembly. This ensures particularly high positioning accuracy during retightening, especially without additional gauges.

[0009] Since the area to be plastically deformed is formed without a coating, precisely defined deformation can be achieved directly within the casing itself. This is particularly advantageous if the casing is made of a material with a lower hardness than the coating.

[0010] Furthermore, a particularly good seal can be achieved between the housing and frame interfaces through plastic deformation. Since a portion of the coating remains between the housing and frame interfaces and is compressed by the threaded connection between them, the coating can provide an additional sealing surface to, for example, prevent water ingress.

[0011] Another advantage is the form fit, which results in a threaded connection that is particularly robust and reliable under lateral loads. Specifically, the form fit prevents adjacent components from sliding relative to each other in a plane perpendicular to the helical axis. This allows the housing and frame interfaces to be designed purely for constant loads, making them particularly simple and inexpensive to manufacture. Furthermore, a particularly robust and reliable threaded connection can be achieved throughout its service life, even with variations in the load acting on one or more components of the threaded connection. Preferably, there is frictional locking between the screw and frame interfaces; that is, each contact surface, perpendicular to the helical axis and pressed against each other by preload, is planar. This avoids vibrational loads on the screw and potential screw breakage, for example, when forces are applied to the drive mechanism.

[0012] Preload is specifically considered as the minimum installation preload necessary for tightening, particularly to generate a predetermined clamping force between the housing and frame interface after plastic deformation. Threaded connections are preferably configured such that a minimum preload exists when tightening the screws with a predetermined tightening torque, preferably at least 8 Nm, preferably at most 12 Nm, and particularly preferably 10 Nm.

[0013] The technical solution according to the present invention includes preferred developments of the present invention.

[0014] The area to be plastically deformed preferably has a lower hardness than the surface structure. Specifically, the hardness here is considered to be Rockwell hardness and / or Brinell hardness and / or Vickers hardness and / or Martens hardness. The area to be deformed is particularly preferably at least 5%, preferably at least 20%, lower than the Vickers hardness. This allows for particularly simple and reliable achievement of the predetermined plastic deformation while the surface structure remains unchanged. The frame interface preferably has a lower hardness than the screws. Furthermore, the outer shell is preferably lower than the frame interface.

[0015] The screw is preferably screwed into a hole in the housing, wherein the area of ​​the housing surrounding the hole is formed without a coating. In particular, the uncoated area surrounding the hole corresponds to the area of ​​the housing to be plastically deformed. This allows for a particularly compact arrangement and advantageous hole sealing.

[0016] The surface structure preferably has an annular cutting edge, which is formed concentrically with respect to the helical axis. The annular cutting edge is considered to be an element that protrudes from the surface of the frame interface and is formed in a tapered manner, particularly conical, in cross-section. The annular cutting edge provides a particularly simple geometry that can be manufactured inexpensively and allows for plastic deformation of the housing area.

[0017] The surface structure preferably has at least one annular groove arranged radially inward and / or radially outward of the annular cutting edge, preferably concentric with respect to the annular cutting edge. The annular groove is considered a recess on the frame interface surface. For example, when the annular cutting edge is pressed into the housing, the bead-like areas of the housing displaced by the annular cutting edge can thereby move into the annular groove.

[0018] The surface structure particularly preferably has at least one indentation. The at least one indentation is preferably in the form of knurling. Knurling can be, for example, cross knurling and / or double cross knurling. Alternatively or additionally, the indentation is preferably a pit, particularly considered to be a circular pit, which preferably has a protrusion caused by the indentation in its outer circumferential direction. Furthermore, the indentation may alternatively or additionally be a star-shaped configuration. Multiple indentations as a surface structure are particularly advantageous.

[0019] At least a portion of the drive unit preferably has lower strength than the frame interface. Alternatively or additionally preferably, the frame interface has lower strength than the screw.

[0020] The housing is preferably made of magnesium. The housing is particularly preferably a casting. Also preferably, the frame interface is formed of aluminum or steel. The screws are preferably made of steel.

[0021] The housing particularly preferably has a sleeve, especially as a separate component. The sleeve is arranged in the housing opening of the housing. Screws are screwed into the sleeve, particularly into the hole of the sleeve. The area of ​​the housing to be plastically deformed is located radially outside the housing opening, i.e. radially outside the sleeve. The sleeve may be formed, for example, from a different material than the housing, such as aluminum, so as to allow for a particularly strong threaded connection.

[0022] Preferably, the coating is a powder coating. In particular, this provides mechanical and corrosion protection for the housing.

[0023] Furthermore, the present invention results in a vehicle, preferably one operable by muscle force and / or motor power, and more preferably an electric bicycle, comprising the described drive mechanism. Through a special threaded connection in the drive mechanism, the housing can be mounted on the vehicle with exceptional precision, thereby always ensuring optimal positioning relative to other components of the vehicle, such as the vehicle frame.

[0024] The vehicle preferably includes a vehicle frame, wherein the frame interface of the threaded connection device is an integral part of the vehicle frame. Alternatively, the frame interface of the threaded connection device is a separate component threaded onto the vehicle frame, wherein the frame interface is preferably a mounting plate. This allows for precise and repeatable installation of the vehicle drive unit in a particularly simple and cost-effective manner.

[0025] Furthermore, the present invention relates to a method for manufacturing a drive mechanism for a vehicle, which is particularly operable by muscle force and / or motor power. The method includes steps performed sequentially, particularly in the aforementioned order: - Provides a housing having a drive unit located therein, wherein the housing is partially coated. - Positioning the shell relative to the vehicle's frame interface using calibration tools, and - Initially, the housing is screwed onto the frame interface with a predetermined preload using screws, causing a predetermined surface structure of the frame interface to plastically deform a region of the housing by means of the preload. A coating is formed on the housing such that, with the housing and frame interface screwed together, the coating is at least partially located between the housing and the frame interface, and the area to be plastically deformed is uncoated. Therefore, this method allows for simple installation and, particularly simple, reinstallation onto the frame interface of a vehicle after the drive unit has been removed.

[0026] The method also preferably includes the following, particularly, consecutive steps: - Loosen the threaded connection. - The shell is positioned relative to the vehicle frame by means of the surface structure and the areas of plastic deformation of the shell, and - Use screws to re-screw the housing onto the frame interface.

[0027] The step of providing the housing particularly preferably includes the step of coating the housing. The area to be plastically deformed is shielded, or in other words covered, by a masking element during coating to prevent coating of the area to be plastically deformed. This makes it particularly easy to ensure that the area to be deformed is formed without a coating.

[0028] The step of providing the housing preferably includes the following steps: - Coated casing, and - Remove the coating from the area to be plastically deformed. That is, during the manufacturing process of the drive unit, the area of ​​the housing to be deformed is first coated simultaneously, and then the coating in that area is removed. For example, the area to be deformed may be formed in a way that protrudes from the surrounding area of ​​the housing, thereby allowing the coating in that area to be removed in a particularly simple manner, such as by abrasion. Attached Figure Description

[0029] The present invention will now be described with reference to the accompanying drawings and exemplary embodiments. Components with the same or similar functions are represented by the same reference numerals in the drawings, wherein: Figure 1 A cross-sectional view of a drive device according to a first exemplary embodiment of the present invention is shown; Figure 2 It shows Figure 1 A cross-sectional view of the drive unit components during the production of the components; Figure 3 It shows Figure 1 A cross-sectional view of a component of the drive unit during an alternative manufacturing method of the component; Figure 4 A detailed view of the frame interface of the drive device according to a second exemplary embodiment of the present invention is shown; Figure 5 A detailed view of the frame interface of the drive device according to a third exemplary embodiment of the present invention is shown; and Figure 6 A simplified schematic diagram of a vehicle having a drive device according to one of the exemplary embodiments of the present invention is shown. Detailed Implementation

[0030] Figure 1 A cross-sectional view of a drive device 10 according to a first exemplary embodiment of the present invention is shown. Figure 1 Only a partial cross-section of the drive unit 10 is shown. The drive unit 10 includes a housing 1 in which a drive unit (not shown) is located, as well as a frame interface 2 and screws 3.

[0031] The drive unit includes a motor and / or gear mechanism (not shown) and is surrounded by a housing 1.

[0032] Frame interface 2 is designed as a fixing plate to secure the housing 1 to the vehicle frame 105 of the vehicle 100 (see...). Figure 6 ).

[0033] The housing 1 and the frame interface 2 are screwed together along the helical axis 30 by means of screws 3. The fastening part 14 of the housing 1 is shown in... Figure 1 In the middle, the housing 1 has a housing opening 19, in which a sleeve 18, which can be considered part of the housing 1, is arranged. A screw 3 is screwed into a hole 16 in the sleeve 18 by means of threads. A frame interface 2 is arranged between the screw head 31 of the screw 3 and the housing 1.

[0034] Tightening the screw 3 with a predetermined torque generates a predetermined preload 5, which is applied to the frame interface 2 parallel to the helical axis 30.

[0035] During the initial screwing of the drive unit 10 together, the housing 1 and the frame interface 2 are preferably aligned relative to each other by means of a special gauge (not shown) in order to allow for precise positioning.

[0036] The frame interface 2 has a predetermined surface structure 4, which is designed as a bulge on the lower side 21a of the frame interface 2. The frame interface 2 and the housing 1 are designed such that during the initial screwing of the drive device 10 together, the surface structure 4 penetrates the upper side 60 of the housing 1 facing the frame interface 2, that is, plastically deforms region 6 of the housing 1 in a predetermined manner. In particular, an imprint corresponding to the shape of the surface structure 4 is formed at a predetermined depth 63 in the upper side 60 of the housing 1. This predetermined plastic deformation occurs whenever the frame interface 2 presses against the housing 1 with a predetermined preload. To specifically induce plastic deformation, the hardness of the housing 1 is lower than that of the frame interface 2.

[0037] The outer casing 1 is preferably made of magnesium, and the frame interface 2 is made of aluminum or steel.

[0038] To provide good protection against environmental impact, especially good corrosion protection, the outer casing is partially coated with coating 7. Coating 7 is a powder coating.

[0039] The coating 7 is also partially located between the frame interface 2 and the housing 1. Thus, when screwed together, this portion of the coating 7 is sandwiched between the frame interface 2 and the housing 1 and is also partially deformed. The coating 7 thus forms a seal between the frame interface 2 and the housing 1 to prevent, for example, water penetration.

[0040] Since the coating 7 has a high hardness in order to better protect the outer shell 1, it is advantageous to form an uncoated state in the plastic deformation area 6 of the outer shell 1, so that the surface structure 4 can directly deform the material of the outer shell 1 during tightening.

[0041] To ensure that the area 6 to be plastically deformed is free of coating, in a first variation of the manufacturing method of the drive unit 10, a portion of it is... Figure 2 As shown in the figure, the region 6 to be deformed can be masked.

[0042] In detail, in this respect, when the outer casing 1 is coated with coating 7, such as Figure 2 As shown in (a), a masking element 50 is used. The masking element 50 has a head 51 and a shaft 52 that can be pushed into the housing opening 19. The head 51 has an outer diameter 61 that corresponds to the outer diameter of the area 6 to be deformed and to be kept uncoated, and this outer diameter is larger than the inner diameter 69 of the housing opening 19. During coating, the head 51 rests against the upper side 60 of the housing 1, thus preventing the area 6 to be deformed from being coated in order to obtain Figure 2 (b) shows the outer casing 1 with an uncoated area 6.

[0043] Figure 3 It shows something similar to Figure 2 As part of an alternative production method, the difference lies in that the area 6 of the outer shell 1 to be plastically deformed is initially coated, such as Figure 3 As shown in (a). The coating 7 in region 6 was subsequently removed (see [reference]). Figure 3 (b)).

[0044] To enable simple, economical, and precise removal of coating 7 only in region 6, housing 1 has a shoulder 64 that protrudes from the rest of housing 1 and has an outer diameter corresponding to the outer diameter 61 of region 6 to be plastically deformed. The shoulder 64 protrudes from the rest of housing 1 by at least a predetermined distance 65. The shoulder 64 allows for particularly simple removal of coating 7, for example, by abrasion, in order to provide... Figure 3 (b) shows the outer casing 1 with an uncoated area 6.

[0045] The special deformation of the surface structure 4 of the frame interface 2 causes the outer shell 1 to retain plastic deformation in region 6 even after the threaded connection is loosened. For example, if the outer shell 1 with the drive unit must be removed from the vehicle frame 105 for maintenance purposes, the connection may need to be loosened. When the drive unit 10 is screwed back together, the precise positioning of the initial tightening can be easily reproduced by aligning the surface structure 4 and the plastically deformed region 6 with each other. Therefore, the drive unit 10 provides a simple and cost-effective design that allows for precise and repeatable installation at a particularly low cost.

[0046] Furthermore, the interlocking of the surface structure 4 and the plastically deformed region 6 provides additional sealing, especially to reliably prevent water from seeping into the housing 1.

[0047] Another advantage of the drive unit 10 is that the surface structure 4 and the plastically deformed region 6 form a form fit, which operates in a plane 35 perpendicular to the helical axis 30. That is, the surface structure 4 and the corresponding indentation produced mesh with each other relative to the plane 35, thus creating a form fit. The form fit functions here in addition to the frictional fit generated by the clamping force of the screw 3. In this way, particularly high lateral forces can be transmitted by means of a threaded connection. In particular, this can reliably prevent slippage between the frame interface 2 and the housing 1.

[0048] exist Figure 1 In the first exemplary embodiment, the surface structure 4 is designed in the form of an annular cutting edge 41. The annular cutting edge 41 is formed concentrically with respect to the helical axis 30 or with respect to the axis of the hole on the lower side 21a of the frame interface 2. The annular cutting edge 41 is formed in a tapering manner, preferably conical, along the direction of the housing 1 in cross-section. The annular cutting edge 41 allows for particularly targeted and simple drilling into the housing 1 during initial screwing. Furthermore, this allows for particularly simple and precise re-screwing, as the tapering geometry allows the frame interface 2 and the housing 1 to be easily repositioned and aligned with each other during re-screwing.

[0049] Figure 4 A detailed view of the frame interface 2 of the drive device 10 according to a second exemplary embodiment of the present invention is shown. The second exemplary embodiment substantially corresponds to... Figure 1 The first exemplary embodiment is described, but it has an alternative surface structure 4. The surface structure 4 is designed here in the form of a plurality of indentations 45, specifically in the form of circular recesses 45b arranged around the opening 20 through which the screw shank 32 of the screw 3 protrudes.

[0050] like Figure 4 As shown, three rows are formed, each row having multiple pits 45b evenly distributed along the circumferential direction. The indentations 45 cause plastic deformation of region 6 of the outer shell 1 in a manner similar to a ring-shaped cutting edge 41.

[0051] Figure 5 A detailed view of the frame interface 2 of the drive device 10 according to a third exemplary embodiment of the present invention is shown. The third exemplary embodiment substantially corresponds to... Figure 4 The second exemplary embodiment is shown, but it has an alternative construction of indentation 45. In the third exemplary embodiment, the indentation is designed in the form of knurling 45a. Figure 5(a) shows a cross knurling pattern with a diamond shape. Figure 5 (b) shows another variation of knurling 45a, which is in the form of double cross knurling, with two additional indentations on each diamond-shaped area to produce a greater degree of roughness. Knurling 45a brings with it... Figure 4 It has a similar effect to the pit 45b.

[0052] Figure 6 A simplified schematic diagram of a vehicle 100 is shown, which can be operated by muscle force and / or motor power and includes a drive unit 10 according to one of the described exemplary embodiments. The vehicle 100 is an electric bicycle with an electric motor for assisting the cyclist's pedaling force. The electric motor is part of the drive unit 10 and is powered by a rechargeable battery 102. The frame interface 2 of the drive unit 10 is part of and / or connected to or can be connected to the vehicle frame 105 of the vehicle 100.

Claims

1. A drive unit for a vehicle (100) includes: - Outer shell (1), - The drive unit inside the housing (1), - Framework interface (2), and - Screw (3). The outer shell (1) and the frame interface (2) are screwed together along the helical axis (30) by means of the screws (3). The outer casing (1) is partially coated with a coating (7) such that, with the outer casing and the frame interface screwed together, at least a portion of the coating (7) is disposed between the outer casing (1) and the frame interface (2). The frame interface (2) has a predetermined surface structure (4) designed to plastically deform a region (6) of the housing (1) with at least one predetermined preload (5) during the initial screwing of the housing and the frame interface together, such that the surface structure (4) and the plastically deformed region (6) form a shape fit in a plane (35) perpendicular to the helical axis (30), and The area (6) to be plastically deformed is formed without a coating.

2. The driving device according to claim 1, wherein, The hardness of the region (6) to be plastically deformed is lower than the hardness of the surface structure (4).

3. The driving device according to claim 1 or 2, wherein, The screw (3) is screwed into the hole (16) of the housing (1), and the area (6) of the housing (1) surrounding the hole (16) is formed without coating.

4. The driving device according to claim 1 or 2, wherein, The surface structure (4) has an annular cutting edge (41).

5. The driving device according to claim 4, characterized in that, The surface structure (4) has at least one annular groove (42) arranged radially inside and / or radially outside the annular cutting edge (41).

6. The driving device according to claim 1 or 2, wherein, The surface structure (4) has at least one indentation (45).

7. The driving device according to claim 1 or 2, wherein, The outer shell (1) is made of magnesium, and / or the frame interface (2) is made of aluminum or steel.

8. The driving device according to claim 1 or 2, wherein, The housing (1) has a sleeve (18) arranged in the housing opening (19) of the housing (1), the screw (3) is screwed into the sleeve (18), and the area (6) to be plastically deformed is arranged radially outside the housing opening (19).

9. The driving device according to claim 1 or 2, wherein, The coating (7) is a powder coating.

10. The driving device according to claim 1 or 2, wherein, The vehicle can be operated by muscle force and / or motor power.

11. The driving device according to claim 4, wherein, The annular cutting edge (41) is formed concentrically with respect to the helical axis (30).

12. The driving device according to claim 6, wherein, The indentation (45) is in the form of knurling (45a) and / or pitting (45b) and / or star-shaped configuration.

13. A means of transportation, wherein, The vehicle includes a drive unit (10) according to any one of the preceding claims.

14. The vehicle according to claim 13, comprising a vehicle frame (105), wherein, The frame interface (2) of the drive unit (10) is a component of the vehicle frame (105), or the frame interface (2) of the drive unit (10) is screwed onto the vehicle frame (105).

15. The means of transport according to claim 13 or 14, wherein, The vehicle is a bicycle that can be operated by muscle force and / or motor power.

16. The means of transport according to claim 15, wherein, The bicycle in question is an electric bicycle.

17. A method for manufacturing a drive unit (10) for a vehicle (100), wherein, The method includes the following steps: - Provide a housing (1) having a drive unit located therein, wherein the housing (1) is partially coated with a coating (7). - Position the housing (1) relative to the frame interface (2) of the vehicle (100) using a calibration tool, and - Initially, the housing (1) is screwed to the frame interface (2) with a predetermined preload (5) by means of screws (3), such that a predetermined surface structure (4) of the frame interface (2) plastically deforms a region (6) of the housing (1) by means of the preload (5), wherein the coating (7) is formed on the housing such that, in the state where the housing and the frame interface are screwed together, the coating (7) is at least partially located between the housing (1) and the frame interface (2), and the region (6) to be plastically deformed is uncoated.

18. The method according to claim 17, wherein, The vehicle can be operated by muscle force and / or motor power.

19. The method of claim 17, wherein, The method further includes the following steps: - Loosen the threaded connection. - The outer shell (1) is positioned relative to the vehicle frame (105) by means of the surface structure (4) and the plastically deformed region (6), and - The housing (1) is re-screwed to the frame interface (2) by means of the screw (3).

20. The method according to any one of claims 17 to 19, wherein, Providing the housing (1) includes the step of coating the housing (1), and during the coating process, the area to be plastically deformed (6) is shielded by means of a shielding element (50) to avoid coating the area to be plastically deformed (6).

21. The method according to any one of claims 17 to 19, wherein, Providing the housing (1) includes the following steps: - Coating the outer shell (1), and - Remove the coating (7) from the area (6) to be plastically deformed.

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