Gear shaft assembly, electric driving device and vehicle

Abstract

Disclosed are a gear shaft assembly, an electric drive device and a vehicle, the gear shaft assembly (100) comprising: a first shaft (200) rotatably mounted on a bearing (400) around a rotation axis; the first tooth (300) is provided with an axial through cavity (310), and the first tooth is fixedly installed on the first shaft (200) through the axial through cavity (310) and can rotate together with the first shaft (200); the axial through cavity (310) comprises a main body section (311), a first end section (312) and a second end section (313), the first end section (312) and the second end section (313) are arranged on the two sides of the main body section in the axial direction respectively, the main body section (311) is in clearance fit with the first shaft (200), and the first end section (312) and the second end section (313) are in interference fit with the first shaft (200).

Description

Technical Field

[0001] The present invention relates to the field of tooth - shaft fitting, and more particularly to a tooth - shaft assembly, an electric drive device, and a vehicle. Background Art

[0002] With the wide application of tooth - shaft assemblies in civil and commercial uses, the installation and fitting methods of tooth - shaft assemblies themselves are facing higher requirements.

[0003] Currently, in a tooth - shaft assembly including a shaft component and a gear component, generally, the installation of the gear component and the shaft component adopts a press - fit method. And in the through - cavity of the gear component, there are a main body section and an end section abutting against the shaft component. The main body section of the gear component and the shaft component are set to form an interference fit. For example, an interference fit is formed through the internal spline of the gear in the main body section and the mating spline of the shaft component. And the end section of the gear component and the shaft component are set to form a clearance fit. However, this results in that during the process of pressing the gear onto the shaft component, due to the pressing force, a large deformation will be formed in the main body section of the gear component along the radial direction of the gear. This will cause deformation of the tooth surface of the main structure of the gear, and make the tooth - shaft assembly generate noise during operation, resulting in poor performance of the noise, vibration, and harshness (NVH) of the tooth - shaft assembly.

[0004] Therefore, there is a need for a tooth - shaft assembly that can significantly reduce the pressing force borne by the main body section of the tooth component, reduce the deformation of the tooth surface of the main body section of the tooth component, and reduce the mechanical noise of the overall tooth - shaft assembly during operation on the premise of achieving a good press - fit between the tooth component and the shaft component in the tooth - shaft assembly. Summary of the Invention

[0005] In view of the above problems, the present invention provides a tooth - shaft assembly, an electric drive device, and a vehicle.

[0006] According to one aspect of the present invention, a tooth - shaft assembly is provided, including: a first shaft rotatably mounted on a bearing about a rotation axis; a first tooth having an axially through - cavity, the first tooth being fixedly mounted on the first shaft via the axially through - cavity and capable of rotating together with the first shaft; wherein, the axially through - cavity includes a main body section, a first end section and a second end section respectively arranged on both sides of the main body section in the axial direction, the main body section forms a clearance fit with the first shaft, and the first end section and the second end section form an interference fit with the first shaft.

[0007] By using the tooth shaft assembly provided by the present invention, on the basis of achieving a good press-fitting between the tooth component and the shaft component in the tooth shaft assembly, the press-fitting force borne by the main body section of the tooth component can be significantly reduced, the tooth surface deformation of the main body section of the tooth component can be reduced, and the mechanical noise of the overall tooth shaft assembly during operation can be reduced.

[0008] The tooth shaft assembly according to the present disclosure may also have one or more of the following features alone or in combination.

[0009] In some embodiments, a first internal spline is provided on the main body section of the first tooth, and a spline mating shaft section is correspondingly provided on the first shaft.

[0010] In some embodiments, the first end section abuts against the bearing, and the first end section forms a shaft hole fit with the corresponding shaft hole mating shaft section of the first shaft.

[0011] In some embodiments, the second end section also forms a shaft hole fit with the corresponding shaft hole mating shaft section of the first shaft.

[0012] In some embodiments, a second internal spline is provided on the second end section, and a tooth shaft mating shaft section is correspondingly provided on the first shaft. The tooth crest of the spline of the second internal spline forms a tooth shaft fit with the tooth shaft mating shaft section of the first shaft.

[0013] In some embodiments, the inner diameter of the first end section is greater than the inner diameter of the main body section, and the inner diameter of the second end section is less than the inner diameter of the main body section.

[0014] In some embodiments, the inner diameter of the first end section is greater than the inner diameter of the main body section, and the inner diameter of the second end section is less than the inner diameter of the main body section; internal splines are simultaneously formed on the main body section and the second end section through a single broaching process.

[0015] In some embodiments, the diameter of the tooth shaft mating shaft section of the first shaft is less than the diameter of the spline mating shaft section of the first shaft, and the diameter of the spline mating shaft section of the first shaft is less than the diameter of the shaft hole mating shaft section of the first shaft.

[0016] In some embodiments, the first shaft is a motor shaft, and the first tooth is the input gear of the motor.

[0017] According to another aspect of the present disclosure, an electric drive device is provided, including the tooth shaft assembly as described above.

[0018] According to another aspect of the present disclosure, a vehicle is provided, including the electric drive device as described above. Description of the Drawings

[0019] To more clearly illustrate the technical solutions of the embodiments of the present invention, the following will briefly introduce the accompanying drawings required for the description of the embodiments. Obviously, the accompanying drawings in the following description are only some embodiments of the present invention. For those of ordinary skill in the art, without creative efforts, other accompanying drawings can also be obtained based on these drawings. The following accompanying drawings are not deliberately drawn to scale in actual size, and the focus is on showing the gist of the present invention.

[0020] Figure 1 Shows a schematic diagram of a gear shaft assembly 100 according to an embodiment of the present disclosure;

[0021] Figure 2 Shows a perspective view of a first gear 300 according to a first embodiment of the present disclosure;

[0022] Figure 3 Shows a cross-sectional view of a first gear 300 according to a first embodiment of the present disclosure;

[0023] Figure 4 Shows a perspective view of a first gear 300 from another angle according to a first embodiment of the present disclosure;

[0024] Figure 5 Shows a side view of a first shaft 200 according to a first embodiment of the present disclosure;

[0025] Figure 6A Shows a cross-sectional view of a gear shaft assembly 100 according to a first embodiment of the present disclosure;

[0026] Figure 6B Shows a cross-sectional view of a first gear 300 according to a second embodiment of the present disclosure;

[0027] Figure 6C Shows a cross-sectional view of a gear shaft assembly 100 according to a second embodiment of the present disclosure;

[0028] Figure 7 Shows Figure 6A a cross-sectional view of the first gear 300 in

[0029] Figure 8 Shows a cross-sectional view of a first shaft 200 according to an embodiment of the present disclosure;

[0030] Figure 9 Shows a schematic diagram of an oil outlet 500 provided near the gear shaft assembly 100 according to an embodiment of the present disclosure;

[0031] Figure 10 Shows a schematic diagram of lubricating oil flowing in the gear shaft assembly 100 according to an embodiment of the present disclosure. Detailed implementation manners

[0032] The technical solutions in the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some of the embodiments of the present invention, rather than all embodiments. All other embodiments obtained by those of ordinary skill in the art based on the embodiments of the present invention without creative efforts shall also fall within the protection scope of the present invention.

[0033] As used in this application and the claims, unless the context clearly dictates otherwise, the words "a", "an", "one", and / or "the" are not specifically singular and may also include the plural. Generally speaking, the terms "comprising" and "including" only indicate the inclusion of the steps and elements that have been clearly identified, and these steps and elements do not constitute an exclusive list. The method or device may also include other steps or elements.

[0034] Although this application makes various references to certain modules in the system according to the embodiments of this application, however, any number of different modules can be used and run on the user terminal and / or the server. The modules are only illustrative, and different aspects of the system and method can use different modules.

[0035] Flowcharts are used in this application to illustrate the operations performed by the system according to the embodiments of this application. It should be understood that the operations before or below do not necessarily have to be performed precisely in order. On the contrary, as needed, various steps can be performed in reverse order or simultaneously. At the same time, other operations can also be added to these processes, or one or several operations can be removed from these processes.

[0036] According to one aspect of the present disclosure, a gear shaft assembly 100 is provided. It should be understood that the gear shaft assembly refers to a combined assembly having a toothed component (such as a gear) and a shaft component.

[0037] Figure 1 A schematic diagram of the gear shaft assembly 100 according to an embodiment of the present disclosure is shown. Referring to Figure 1 , the gear shaft assembly 100 includes: a first shaft 200 and a first gear 300.

[0038] The first shaft 200 represents a rotating shaft component, which is rotatably mounted on a bearing 400, for example, about a rotation axis. For example, as Figure 1 shown, for example, two support bearings 400 can be provided at both ends of the first shaft, and the first shaft is rotatably mounted on the bearings 400 at both ends.

[0039] It should be understood that the embodiments of the present disclosure are not limited by the specific type of the bearing and the specific mounting manner of the first shaft on the bearing.

[0040] Figure 2Shows a perspective view of a first tooth 300 according to a first embodiment of the present disclosure. Referring to Figure 2 , the first tooth 300 represents a gear assembly having an axially through cavity 310. The first tooth 300 is fixedly mounted on the first shaft 200 via the axially through cavity 310 and is capable of rotating together with the first shaft 200.

[0041] The axially through cavity 310 refers to a through cavity that extends in a direction parallel to the rotation axis of the first shaft within the first tooth and penetrates the first tooth. It can be, for example, a through cavity having a generally cylindrical shape.

[0042] The first tooth is, for example, mounted to a corresponding section on the first shaft 200 via the axially through cavity 310, thereby achieving the installation of the first tooth and the first shaft and forming the tooth-shaft assembly.

[0043] The first tooth being capable of rotating together with the first shaft means that the first tooth can be fixedly mounted to the first shaft and rotate together at the same angular velocity.

[0044] For example, as Figure 1 shown, the first tooth can be, for example, mounted at one end (cantilever end) of the first shaft and abutted against a bearing 400 of the first shaft to achieve the installation.

[0045] Figure 3 Shows a cross-sectional view of the first tooth 300 according to a first embodiment of the present disclosure. Referring to Figure 3 , the axially through cavity 310 can include, for example, a main section 311 and a first end section 312 and a second end section 313 respectively disposed on both sides of the main section in the axial direction.

[0046] The main section 311 refers to the cavity section that forms the main part of the axially through cavity. The length of the main section can correspond to the length of the main structure of the gear in the axial direction, for example.

[0047] For example, it can be centrally disposed in the axis through cavity and occupy 50% of the axially through cavity, or it can also occupy 70% of the axially through cavity. It should be understood that the embodiments of the present disclosure are not limited by the specific extension length and scope of the main section.

[0048] The end sections refer to the cavity sections that are disposed on both sides of the main section and form the two end parts of the axis through cavity. The present disclosure is not limited by the specific extension length and scope of the end sections.

[0049] It should be understood that the first end section and the second end section are only intended to distinguish two different sections disposed on both sides of the main section and are not intended to limit them.

[0050] And among them, the main body section 311 forms a clearance fit with the first shaft 200, and the first end section 312 and the second end section 313 form an interference fit with the first shaft 200.

[0051] The clearance fit refers to an installation fit method with a clearance (including the minimum clearance being equal to zero), that is, when the gear shaft is assembled, there is a clearance between the main body section 311 of the first gear 300 and the first shaft 200.

[0052] The interference fit refers to an installation fit method that relies on the interference value between the shaft and the hole to generate elastic pressure between the surfaces of the parts after assembly, thereby obtaining a firm connection. That is, when the gear shaft is assembled, elastic pressure is generated between the first end section 312 of the first gear 300 and the first shaft 200, and between the second end section 313 and the first shaft 200, so as to realize the fixed installation of the first gear and the first shaft through the first end section 312 and the second end section 313.

[0053] It should be understood that the present application is not limited by this specific clearance fit method (such as spline clearance fit, etc.) or specific interference fit method (such as gear shaft interference, hole shaft interference, etc.).

[0054] Based on the above, in the present application, by setting the first gear of the gear shaft assembly to be fixedly installed on the first shaft via the axially penetrating cavity and capable of rotating together with the first shaft, and further setting that the main body section of the axially penetrating cavity forms a clearance fit with the first shaft, and the first end section and the second end section form an interference fit with the first shaft, so that during the installation process of the tooth component and the shaft component of the gear shaft assembly, compared with the current situation where the inner spline in the main body section of the gear forms an interference fit with the mating spline of the shaft component, by forming an interference fit through the end sections at both ends of the tooth component and the shaft component to achieve a firm installation, while the main body section forms a clearance fit with the shaft component, so that during the process of press-fitting the tooth component onto the shaft component for installation, there will be no press-fitting force on the main body section of the tooth component due to the clearance fit, and the tooth surface on the main body structure of the gear will not be deformed during the installation process, which can greatly reduce the deformation of the tooth surface of the main body section of the tooth component, and reduce the mechanical noise of the overall gear shaft assembly during operation; and at the same time, by realizing the installation through interference fit at both end sections, on the basis of realizing the stable installation of the tooth component on the shaft component, it is also beneficial to keep the tooth component well in place on the shaft component through the installation at both ends, especially in the axial direction.

[0055] Figure 4 A perspective view of the first gear 300 from another angle according to the first embodiment of the present disclosure is shown. Figure 5 A side view of the first shaft 200 according to the first embodiment of the present disclosure is shown.

[0056] Combined reference Figure 4 and Figure 5 In some embodiments, a first internal spline 321 is provided on the main body section 311 of the first tooth 300, and the first shaft 200 is correspondingly provided with a spline mating shaft section 210.

[0057] The first internal spline refers to a spline portion that projects inward from the axis through cavity within the main body section 311 of the first tooth 300. It should be understood that the embodiments of the present disclosure are not limited by the specific spline type and the number of splines of the first internal spline.

[0058] The spline mating shaft section 210 can be, for example, an external spline section at a position corresponding to the main body section on the shaft. The external spline on the spline mating shaft section can cooperate with the first internal spline of the main body section of the first tooth, thereby achieving a good assembly between the tooth and the shaft.

[0059] Based on the above, in the present application, by providing a first internal spline on the main body section of the first tooth and correspondingly providing a spline mating shaft section on the first shaft, it is possible to achieve a clearance fit between the first tooth and the first shaft on the main body section in a simple and convenient spline mating manner, which is beneficial to simplifying the manufacturing process.

[0060] Figure 6A A cross-sectional view of a tooth-shaft assembly 100 according to a first embodiment of the present disclosure is shown, in which two end sections are in different interference fit manners with the first shaft.

[0061] Combined reference Figure 4 、 Figure 5 and Figure 6A In some embodiments, the first end section 312 abuts against the bearing 400, for example, and the first end section 312 forms a shaft-hole fit with the corresponding shaft-hole mating shaft section 230 of the first shaft 200.

[0062] The shaft-hole fit refers to achieving an interference fit through the fit between the shaft and the hole. Specifically, that is, the diameter of the shaft section of the paired first shaft is equal to or greater than the hole diameter of the corresponding first tooth.

[0063] The shaft-hole mating shaft section 230 refers to the section on the shaft for mating with the end section of the first tooth.

[0064] Specifically, for example, the first end section 312 of the axially through cavity 310 of the first tooth is formed as an opening, the aperture of the opening (i.e., the inner diameter hereinafter) is d1, for example, and the shaft-hole mating shaft section of the first shaft corresponding to the first end section has a diameter z1, and the shaft diameter z1 of the shaft-hole mating shaft section is slightly greater than the aperture d1 of the opening of the first end section 312.

[0065] Based on the above, in the present application, by arranging the first end section to abut against the bearing and arranging the first end section to form a shaft-hole fit with the corresponding shaft-hole fit section of the first shaft, it is possible to simply and conveniently achieve an interference fit between the first end section and the shaft through the shaft-hole fit, thereby simplifying the manufacturing process.

[0066] Figure 6B Shows a cross-sectional view of the first tooth 300 according to the second embodiment of the present disclosure; Figure 6C Shows a cross-sectional view of the tooth shaft assembly 100 according to the second embodiment of the present disclosure, in which both end sections form a hole-shaft fit with the first shaft.

[0067] Referring to Figure 6B and Figure 6C , in some embodiments, the first end section 312 and the second end section 313 can, for example, achieve an interference fit with the first shaft in the same way. Specifically, on the basis that the first end section 312 forms a shaft-hole fit with the corresponding shaft-hole fit section 230 of the first shaft 200, the second end section 313 also forms a shaft-hole fit with the corresponding shaft-hole fit section 230 of the first shaft 200.

[0068] The shaft-hole fit refers to achieving an interference fit through the fit of a shaft and a hole. Specifically, that is, the diameter of the shaft section of the paired first shaft is equal to or greater than the hole diameter of the corresponding first tooth.

[0069] The shaft-hole fit section 230 refers to the section on the shaft for fitting with the opening of the end section of the first tooth.

[0070] Specifically, for example, the second end section 313 of the axially through cavity 310 of the first tooth is formed as an opening, and the opening has a hole diameter (i.e., the inner diameter hereinafter) d3, and the shaft-hole fit section of the first shaft corresponding to the second end section 313 has a diameter z3, and the diameter z3 of the shaft-hole fit section can, for example, be slightly larger than the hole diameter d3 of the opening of the first end section 312.

[0071] Based on the above, in the present application, by arranging both the first end section and the second end section to form a shaft-hole fit with the corresponding shaft-hole fit section of the first shaft, it is possible to simply and conveniently achieve an interference fit between the first end section, the second end section and the shaft through the shaft-hole fit, thereby simplifying the manufacturing process.

[0072] Comprehensively referring to Figure 4 , Figure 5 and Figure 6A , in some embodiments, the first end section 312 and the second end section 313 can, for example, achieve an interference fit with the first shaft in different ways.

[0073] The second end section 313 (e.g., the end section away from the bearing) is provided with a second internal spline 322, and the first shaft 200 is correspondingly provided with a spline shaft mating section 220. The crest of the spline teeth of the second internal spline 322 forms a spline shaft mating with the spline shaft mating section 220 of the first shaft 200.

[0074] The spline shaft mating refers to a mating method in which an interference fit is formed between the crest of the corresponding internal spline teeth at the end section of the first tooth and the first shaft (specifically, the outer diameter of the first shaft).

[0075] It should be understood that the second internal spline 322 refers to a spline portion that protrudes inward from the axial through cavity toward the first tooth on the second end section of the first tooth 300. It should be understood that the embodiments of the present disclosure are not limited by the specific spline type and the number of splines of the second internal spline.

[0076] The spline shaft mating section 220 refers to the section on the shaft corresponding to the second end section, such as Figure 5 and Figure 6A As shown, the outer surface of the shaft of the spline shaft mating section 220 can, for example, cooperate with the crest of the spline teeth of the second internal spline 322 of the second end section 313 of the first tooth, so as to achieve a good interference fit between the tooth and the shaft.

[0077] In the present application, when an axial hole mating is formed between the first end section and the first shaft, by further providing that the second end section is provided with a second internal spline, and the first shaft is correspondingly provided with a spline shaft mating section, the crest of the spline teeth of the second internal spline forms a spline shaft mating with the spline shaft mating section of the first shaft, so that the first end section and the second end section of the first tooth can respectively cooperate with the first shaft in two different ways, namely spline shaft mating and hole shaft mating, which is beneficial to improving the installation stability of the spline shaft assembly. In addition, by setting the second end section away from the bearing as the spline shaft mating method, the lubricating oil ejected from the oil outlet near the first shaft can flow into the interior of the spline shaft assembly through the gap between the adjacent splines of the second internal spline, so as to achieve good lubrication of the axial through cavity of the first tooth, especially the first internal spline of the main section thereof, thereby improving the overall lubrication effect of the spline shaft assembly.

[0078] For example, the lubrication process can be described more specifically. Figure 9 FIG. shows a schematic diagram of an oil outlet 500 provided near the spline shaft assembly 100 according to an embodiment of the present disclosure. Figure 10 FIG. shows a schematic diagram of the flow of lubricating oil in the spline shaft assembly 100 according to an embodiment of the present disclosure.

[0079] Referring to Figure 9 andFigure 10 It can be seen that the lubricating oil ejected from the oil outlet 500 provided near the tooth shaft assembly 100 can flow towards the first tooth of the tooth shaft assembly, and for example, flow along the outer surface of the first tooth in the direction of the arrow. Further, it flows into the interior of the tooth shaft assembly 100 through the gap between the first tooth 300 of the tooth shaft assembly 100 and the tooth shaft fit or hole-shaft fit between the first shaft 200 (for example, in the case of a tooth shaft fit, the lubricating oil can flow through the gap between adjacent splines of the second internal spline), that is, it flows into the space between the inner surface of the first tooth 300 and the outer surface of the first shaft 200, as Figure 10 shown by the arrow in [reference], thereby achieving good lubrication of the axial through cavity (especially the first internal spline in the main body section) of the first tooth and the first shaft.

[0080] In some embodiments, the inner diameter d1 of the first end section 312 is greater than the inner diameter d2 of the main body section 311, and the inner diameter d3 of the second end section 313 is less than the inner diameter d2 of the main body section 311.

[0081] It should be understood that the inner diameter refers to the diameter of the inner surface of the corresponding section of the axially extending cavity inside the first tooth.

[0082] For example, if the axially extending cavity is cylindrical, and the first end section, the second end section form a hole-shaft fit with the first shaft, and the main body section forms a spline fit with the first shaft, then the aperture of the opening formed by the first end section is the inner diameter d1 of the first end section, the aperture of the opening formed by the second end section is the inner diameter d3 of the second end section, and the diameter of the circumscribed circle surrounded by the root of the spline teeth of the first internal spline in the main body section (that is, the opening of the main body section before the internal spline is provided) is the inner diameter d2 of the main body section.

[0083] For example, if the first end section and the second end section form a hole-shaft fit and a tooth shaft fit with the first shaft respectively, then the aperture of the opening formed by the first end section is the inner diameter d1 of the first end section, and the diameter of the circumscribed circle surrounded by the root of the spline teeth of the second internal spline in the second end section (that is, the opening of the second end section before the internal spline is provided) is the inner diameter d3 of the second end section.

[0084] Figure 7 shows Figure 6A a cross-sectional view of the first tooth 300 in [reference]. Referring to Figure 7 it can be seen that the inner diameter d1 of the first end section 312 is greater than the inner diameter d2 of the main body section 311, and the inner diameter d3 of the second end section 313 is less than the inner diameter d2 of the main body section 311.

[0085] By setting the inner diameter of the first end portion section to be greater than the inner diameter of the main body section, and the inner diameter of the second end portion section to be less than the inner diameter of the main body section, a good stepped inner diameter reduction can be formed between the first end portion section, the main body section, and the second end portion section, which is beneficial to the good and reliable assembly of the first tooth on the first shaft.

[0086] In some embodiments, as described above, the inner diameter d1 of the first end portion section 312 is greater than the inner diameter d2 of the main body section 311, and the inner diameter d3 of the second end portion section 313 is less than the inner diameter d2 of the main body section 311. In addition, internal splines are simultaneously formed on the main body section 311 and the second end portion section 312 through a single broaching process.

[0087] It should be understood that the broaching process refers to using a broach with a special geometric shape to broach the inner tooth surface of the gear to form splines.

[0088] It should be understood that the specific process of forming the first internal spline and the second internal spline may be, for example: First, form three openings with different inner diameters, namely a first opening corresponding to the inner diameter d1 of the first end portion section 312, a second opening corresponding to the inner diameter d2 of the main body section 311, and a third opening corresponding to the inner diameter d3 of the second end portion section 313. Second, internal splines are simultaneously broached on the main body section 311 and the second end portion section 313 through a single broaching process, that is, through a single broaching process, internal splines on the main body section 311 and the second end portion section 313 are simultaneously formed, without the need for two broaching processes for the main body section 311 and the second end portion section 313 respectively. Finally, the internal spline of the main body section 311 directly forms the aforementioned first internal spline, and further finishing is performed on the internal spline on the second end portion section 313 and the first opening corresponding to the inner diameter d1 of the first end portion section 312. For example, the finishing may be: turning the tooth top of the internal spline on the second end portion section 313 so that the tooth top of the internal spline on the second end portion section 313 can be well adapted to the corresponding mating section of the shaft; performing further finishing on the first opening with the inner diameter d1 of the first end portion section 312 so that the inner diameter of the opening can be well adapted to the corresponding mating section of the shaft, thereby forming a good interference fit with the first shaft through the first end portion section 312 and the second end portion section 313.

[0089] In the present application, by means of a single spline broaching process, internal splines are simultaneously formed in the main body section and the second end section, enabling the internal splines at the two sections to be formed simultaneously via only one spline broaching process, thereby effectively improving the manufacturing efficiency of the first tooth. Moreover, compared with the case where both ends are hole-shaft fits and the splines in the main body section must be formed one by one via a gear shaping process, adopting an interference fit at one end of the tooth shaft and an interference fit at one end of the shaft hole and applying a single spline broaching process will significantly reduce the manufacturing cost.

[0090] Figure 8 FIG. 4 shows a cross-sectional view of a first shaft 200 according to an embodiment of the present disclosure, which is, for example, a hollow shaft. Referring to Figure 8 , in some embodiments, the diameter z3 of the tooth shaft mating shaft section 220 of the first shaft 200 is smaller than the diameter z2 of the spline mating shaft section 210 of the first shaft 200, and the diameter z2 of the spline mating shaft section 210 of the first shaft 200 is smaller than the diameter z1 of the shaft hole mating shaft section 230 of the first shaft 200.

[0091] It should be understood that the embodiments of the present disclosure are not limited by the specific values of the diameters z1, z2, and z3, as long as the relationship z1 > z2 > z3 is satisfied.

[0092] Based on the above, in the present application, in the case of setting the interference fit at one end of the shaft hole and the interference fit at one end of the tooth shaft, by setting the diameter of the tooth shaft mating shaft section of the first shaft to be smaller than the diameter of the spline mating shaft section, and setting the diameter of the spline mating shaft section to be smaller than the diameter of the shaft hole mating shaft section, the first tooth can be well adapted to the corresponding first tooth via the corresponding aperture step setting, thereby achieving good assembly of the tooth shaft assembly.

[0093] In some embodiments, the first shaft 200 is a motor shaft, and the first tooth 300 is the input gear of the motor.

[0094] It should be understood that the motor shaft can be, for example, the input shaft of the motor, and the input gear can be, for example, the output gear installed at one end of the motor input shaft to achieve good torque input.

[0095] Based on the above, in the present application, by setting the first shaft as the motor shaft and the first tooth as the input gear of the motor, good and stable assembly between the motor and the input gear can be achieved via the corresponding structural settings of the tooth shaft assembly provided in the present application, so that on the basis of achieving good force transmission of the motor, the noise during the operation of the motor and the input gear is reduced, and its operating performance is improved.

[0096] According to another aspect of the present disclosure, an electric drive device is proposed, which, for example, includes the tooth shaft assembly 100 as described above, has the structure as described above, and can achieve the functions as described above.

[0097] According to another aspect of the present disclosure, a vehicle is also provided, which includes the electric drive device as described above. As described above, the electric drive device is provided with a gear shaft assembly 100 and can achieve the functions as described above. The vehicle may be an electrified vehicle, such as a battery electric vehicle (BEV), a hybrid electric vehicle (HEV), a plug-in hybrid electric vehicle (PHEV), a range extended electric vehicle, or a fuel cell electric vehicle (FCEV). The vehicle may also be a hydrogen energy vehicle.

[0098] Certain terms are used in this application to describe embodiments of the present application. For example, "the first / second embodiment", "an embodiment", and / or "some embodiments" mean a certain feature, structure, or characteristic related to at least one embodiment of the present application. Therefore, it should be emphasized and noted that the "an embodiment" or "one embodiment" or "an alternative embodiment" mentioned twice or more at different positions in this specification does not necessarily refer to the same embodiment. In addition, certain features, structures, or characteristics in one or more embodiments of the present application may be combined appropriately.

[0099] Unless otherwise defined, all terms (including technical and scientific terms) used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this invention belongs. It should also be understood that terms such as those defined in a commonly used dictionary should be interpreted as having a meaning consistent with their meaning in the context of the relevant art, and should not be interpreted in an idealized or overly formal sense, unless expressly defined as such herein.

[0100] The above is the description of the present invention and should not be construed as a limitation thereof. Although several exemplary embodiments of the present invention have been described, those skilled in the art will readily understand that many modifications can be made to the exemplary embodiments without departing from the novel teachings and advantages of the present invention. Therefore, all such modifications are intended to be included within the scope of the present invention as defined by the claims. It should be understood that the above is the description of the present invention and should not be considered limited to the specific embodiments disclosed, and modifications to the disclosed embodiments and other embodiments are intended to be included within the scope of the appended claims. The present invention is defined by the claims and their equivalents.

Claims

1. A tooth shaft assembly (100), comprising: A first shaft (200) rotatably mounted on a bearing (400) about a rotation axis; A first tooth (300) having an axially through cavity (310), the first tooth being fixedly mounted on the first shaft (200) via the axially through cavity (310) and capable of rotating together with the first shaft (200); Wherein, the axially through cavity (310) includes a main section (311) and a first end section (312) and a second end section (313) respectively arranged on both sides of the main section in the axial direction, the main section (311) forms a clearance fit with the first shaft (200), and the first end section (312) and the second end section (313) form an interference fit with the first shaft (200).

2. The tooth shaft assembly (100) according to claim 1, wherein, A first internal spline (321) is provided on the main section (311) of the first tooth (300), and a spline mating shaft section (210) is correspondingly provided on the first shaft (200).

3. The tooth shaft assembly (100) according to claim 1 or 2, wherein, The first end section (312) abuts against the bearing (400), and the first end section (312) forms a shaft hole fit with a corresponding shaft hole mating shaft section (230) of the first shaft (200).

4. The tooth shaft assembly (100) according to claim 3, wherein, The second end section (313) also forms a shaft hole fit with a corresponding shaft hole mating shaft section (230) of the first shaft (200).

5. The tooth shaft assembly (100) according to claim 3, wherein, A second internal spline (322) is provided on the second end section (313), and a tooth shaft mating shaft section (220) is correspondingly provided on the first shaft (200), and the tooth crest of the second internal spline (322) forms a tooth shaft fit with the tooth shaft mating shaft section (220) of the first shaft (200).

6. The tooth shaft assembly (100) according to claim 3, wherein, The inner diameter of the first end section (312) is greater than the inner diameter of the main section (311), and the inner diameter of the second end section (313) is less than the inner diameter of the main section (311).

7. The tooth shaft assembly (100) according to claim 5, wherein, The inner diameter of the first end section (312) is greater than the inner diameter of the main section (311), and the inner diameter of the second end section (313) is less than the inner diameter of the main section (311); Internal splines are simultaneously formed on the main section (311) and the second end section (312) by a single broaching process.

8. The gear shaft assembly (100) according to claim 5, wherein, The diameter of the tooth shaft mating shaft section (220) of the first shaft (200) is less than the diameter of the spline mating shaft section (210) of the first shaft (200), and the diameter of the spline mating shaft section (210) of the first shaft (200) is less than the diameter of the shaft hole mating shaft section (230) of the first shaft (200).

9. The tooth shaft assembly (100) according to claim 1, wherein the first shaft (200) is a motor shaft, and the first tooth (300) is an input gear of the motor.

10. An electric drive device, comprising the tooth shaft assembly (100) according to any one of claims 1-9.

11. A vehicle, comprising the electric drive device according to claim 10.

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