This application relates to the field of motors, and specifically, to a disk motor, an assembly method for the disk motor, a powertrain, and a vehicle.
Multi-motorization is one of the development trends of a drive motor of an electric vehicle. A final expected form of the drive motor is to implement independent driving of each wheel, to obtain best power performance and maneuverability. Therefore, miniaturization of the motor has become an industry development trend. Under a specific power requirement, there are two ways to make a motor small: One is to make the motor have a high speed, and the other is to make the motor have a high torque density design. Currently, a design of the motor is close to a limit (for example, 20,000 rpm) of a mechanical system (mainly a serrated shaft), but there is still a large space for the high torque density design. An axial flux motor, also referred to as a disk motor, is a motor that forms a closed flux loop through an axial air gap surface of the motor, and has high torque density. An existing disk motor usually includes three structures: a single-stator single-rotor structure, a dual-stator single-rotor structure, and a dual-rotor single-stator structure. The dual-rotor single-stator structure can achieve highest torque density in the foregoing three structures. Therefore, a dual-rotor single-stator motor also gradually becomes a research hotspot.
However, for an existing motor with the dual-rotor single-stator structure, dynamic balance adjustment needs to be performed on a rotor system (rotor+rotating shaft) of the motor before assembly. Currently, a method is to perform dynamic balance adjustment on the rotor through a dummy shaft, and then assemble a stator, the rotor, and the rotating shaft. Because there is a deviation between assembling through the dummy shaft and assembling through an actual rotating shaft, a deviation between a centroid and a rotation center of an entire rotor system is limited by an inherent deviation (approximately 6 to 9 μm) of a current process capability. According to a dynamic balance requirement on the motor in GB9239.1-2006, the motor with a maximum rotational speed more than 950 rpm needs to meet a dynamic balance requirement in G2.5. For example, if a rotational speed is 10,000 rpm, a centroid deviation needs to be limited within approximately 2.5 μm. However, in view of the foregoing inherent deviation, the solution of performing dynamic balance adjustment through the dummy shaft cannot theoretically meet the dynamic balance requirement in G2.5. Another dynamic balance adjustment method is to first perform dynamic balance adjustment on a system with two rotors, then disassemble one of the rotors, and mount the rotor after a stator is mounted. In this method, there are many assembly operations, which is not conducive to improving production efficiency. In addition, repeated disassembly and assembly of a component with interference may easily cause a decrease in reliability of the entire machine. Consequently, the existing dynamic balance adjustment method cannot consider both accurate dynamic balance adjustment and convenient production.
This application provides a disk motor, an assembly method for the disk motor, a powertrain, and a vehicle, to improve accuracy of dynamic balance adjustment and improve assembly convenience.
According to a first aspect, this application provides a disk motor. The disk motor includes a rotating shaft and a first rotor, a stator, and a second rotor that are sleeved on the rotating shaft. The first rotor, the stator, and the second rotor are sequentially spaced apart. The stator is rotatably connected to the rotating shaft, the rotating shaft includes a first shaft body and a second shaft body that are detachably connected to each other, the first shaft body is fastened to the first rotor, and the second shaft body is fastened to the second rotor.
The rotating shaft of the disk motor in this application may be divided into the first shaft body and the second shaft body. The first shaft body is connected to the first rotor, and the second shaft body is connected to the second rotor. Before assembly, dynamic balance adjustment is performed on the first rotor and the first shaft body, and dynamic balance adjustment is performed on the second rotor and the second shaft body. Then, the first shaft body is connected to the second shaft body, and the stator is mounted. In a dynamic balance adjustment process, the first rotor and the second rotor each are adjusted by using a true shaft, so that a problem of poor accuracy caused by using a dummy shaft can be avoided. In the dynamic balance adjustment process, a dynamic balance indicator of a single rotor system (for example, a rotor system including the first rotor and the first shaft body or a rotor system including the second rotor and the second shaft body) may be controlled within a dynamic balance indicator of the entire disk motor (that is, a single-disk dynamic balance requirement is tightened), so that a final dynamic balance indicator of the disk motor meets the requirement. During assembly of the disk motor with this structure, the rotor on which dynamic balance adjustment is performed does not need to be disassembled, and the entire motor is assembled at a time, so that convenience and reliability of assembly can be ensured.
In some embodiments, a connection manner of the first shaft body and the second shaft body includes but is not limited to an interference fit connection, a bonding connection, a coupling connection, a pin connection, a flange connection, and the like. A specific connection manner of the first shaft body and the second shaft body is not limited in this application, provided that the first shaft body and the second shaft body can be connected.
In some embodiments, at least one of a side surface that is of the first rotor and that is perpendicular to the rotating shaft and away from the stator and a side surface that is of the second rotor and that is perpendicular to the rotating shaft and away from the stator is provided with a weight adjustment component. In some embodiments, at least one of a circumferential surface of the first rotor and a circumferential surface of the second rotor may be provided with a weight adjustment component.
In some embodiments, the weight adjustment component includes a fastening element disposed on the first rotor and the second rotor and a weight adjustment block connected to the fastening element through cooperation. For example, the fastening element includes a hole or a protruding column.
In some embodiments, the fastening element is disposed on the side surface that is of the first rotor and that is perpendicular to the rotating shaft and away from the stator, there are a plurality of fastening elements, and the plurality of fastening elements form concentric rings in a radial direction of the first rotor. For example, in any one of the rings formed by the fastening elements, a plurality of fastening elements are evenly arranged in a circumferential direction of the first rotor. The fastening element is disposed on the side surface that is of the second rotor and that is perpendicular to the rotating shaft and away from the stator, there are a plurality of fastening elements, and the plurality of fastening elements form concentric rings in a radial direction of the second rotor. For example, in any one of the rings formed by the fastening elements, a plurality of fastening elements are evenly arranged in a circumferential direction of the second rotor.
According to a second aspect, this application provides an assembly method for the foregoing disk motor. The assembly method includes the following operations:
In some embodiments, the performing dynamic balance adjustment on the first shaft body and the first rotor that are fastened to each other includes: adjusting the weight adjustment component, for a deviation between a centroid and a rotation center of a rotation unit including the first shaft body and the first rotor to satisfy a preset dynamic balance level standard at a preset rotational speed.
In some embodiments, the performing dynamic balance adjustment on the second shaft body and the second rotor that are fastened to each other includes: adjusting the weight adjustment component, for a deviation between a centroid and a rotation center of a rotation unit including the second shaft body and the second rotor to satisfy a preset dynamic balance level standard at a preset rotational speed.
According to a third aspect, this application further provides a powertrain. The powertrain may include a transmission mechanism and the disk motor according to the first aspect of this application. The transmission mechanism is connected to the disk motor. The disk motor may drive the transmission mechanism to move.
According to a fourth aspect, this application further provides a vehicle. The vehicle includes a vehicle frame and the disk motor in this application.
For technical effects that may be implemented in the second aspect and the fourth aspect, refer to corresponding effect descriptions in the first aspect. Details are not described herein again.
To make the objectives, technical solutions, and advantages of this application clearer, the following further describes this application in detail with reference to the accompanying drawings.
Terms used in the following embodiments are merely intended to describe specific embodiments, but are not intended to limit this application. The terms “one”, “a” and “this” of singular forms used in this specification and the appended claims of this application are also intended to include expressions such as “one or more”, unless otherwise specified in the context clearly.
Reference to “an embodiment”, “some embodiments”, or the like described in this specification indicates that one or more embodiments of this application include a specific feature, structure, or characteristic described with reference to the embodiment. Therefore, statements such as “in an embodiment”, “in some embodiments”, “in some other embodiments”, and “in other embodiments” that appear at different places in this specification do not necessarily mean referring to a same embodiment. Instead, the statements mean “one or more but not all of embodiments”, unless otherwise specifically emphasized in another manner. The terms “include”, “have”, and their variants all mean “include but are not limited to”, unless otherwise specifically emphasized in another manner.
For ease of understanding, dynamic balance mentioned in this application is first explained and described. The dynamic balance is research content of rotor dynamics, and is an operation of determining a position and a magnitude of imbalance (a centrifugal force and centrifugal force couple) generated when a rotor rotates, and eliminating the imbalance. The imbalance causes transverse vibration of the rotor, and causes the rotor to be subject to an unnecessary dynamic load. This is not conducive to a normal operation of the rotor. Therefore, before a motor is assembled, dynamic balance adjustment needs to be performed on the rotor, so that a centroid of the rotor is close to a rotation center in a rotation process.
Currently, there is no mature dynamic balance adjustment solution for a multi-rotor disk motor (for example, a disk motor with two rotors and a single stator). In most cases, dynamic balance is performed on each rotor through a dummy shaft, and then the rotors are assembled as a whole. In this adjustment solution, impact of the dummy shaft on the dynamic balance is not considered. Consequently, bearing reliability of the disk motor is reduced, and a problem of excessive vibration (e.g., a vibration amplitude of the motor exceeds a preset value) may be introduced.
To resolve the foregoing problem, this application provides a disk motor.
As shown in
Still refer to
Another connection manner of the first shaft body 141 and the second shaft body 142 is described with reference to
The foregoing connection manners of the first shaft body 141 and the second shaft body 142 are merely examples for description. A specific connection manner of the first shaft body 141 and the second shaft body 142 is not limited in this application, provided that the first shaft body 141 and the second shaft body 142 can be fastened to each other.
Still refer to
Refer to
Still refer to
Still refer to
In addition to the side surface that is of the first rotor 11 and that is perpendicular to the rotating shaft 14, the weight adjustment component 20 may be alternatively disposed on a peripheral side surface of the first rotor 11. In this case, a corresponding adjustment function may also be implemented. Similarly, the weight adjustment component 20 may also be disposed on a peripheral side surface of the second rotor 13. The weight adjustment component 20 may be separately disposed on the peripheral side surface of the first rotor 11, or may be separately disposed on the peripheral side surface of the second rotor 13, or may be disposed on both the peripheral side surface of the first rotor 11 and the peripheral side surface of the second rotor 13.
The first rotor 11 is used as an example. As shown in
When dynamic balance adjustment is performed by using a weight increase method, adjustment may be performed by adding an adjustment block on the fastening element 21 or the like. When dynamic balance adjustment is performed by using a weight decrease method, in addition to adjusting a quantity of weight adjustment blocks 22, adjustment may be performed by providing holes on the first rotor 11 and the second rotor 13. A specific weight adjustment manner is not specifically limited in this embodiment of this application.
Still refer to
For a structure of the weight adjustment component of the second rotor 13, refer to the structure of the weight adjustment component of the first rotor 11. Details are not described herein again.
Operation S11: as shown in
Operation S12: as shown in
Operation S13: as shown in
A sequence of the foregoing operations S11 to S13 is merely an example for description, and the sequence may be adjusted based on an actual requirement. This is not specifically limited herein.
Dynamic balance adjustment of a rotating unit including the first shaft body 141 and the first rotor 11 includes the following operations: adjusting the weight adjustment component, for a deviation between a centroid and a rotation center of the rotation unit including the first shaft body 141 and the first rotor 11 to satisfy a preset dynamic balance level standard, for example, a level standard specified in G2.5, G1.0, and the like in GB/T 9239.1, at a preset rotational speed.
Similarly, dynamic balance adjustment of a rotating unit including the second shaft body 142 and the second rotor 13 includes the following operations: adjusting the weight adjustment component, for a deviation between a centroid and a rotation center of the rotation unit including the second shaft body 142 and the second rotor 13 to satisfy the preset dynamic balance level standard, for example, the level standard specified in G2.5, G1.0, and the like in GB/T 9239.1, at the preset rotational speed.
In the disk motor 10 in embodiments of this application, the rotating shaft 14 is divided into the first shaft body 141 and the second shaft body 142 that are detachably connected to each other. Dynamic balance adjustment is first performed on each rotor system before assembly, and the disk motor 10 is assembled after the dynamic balance adjustment is performed on each rotor system. When dynamic balance adjustment is performed on a single rotor system, a dynamic balance indicator of the single rotor system may be strictly controlled, so that final overall dynamic balance of the disk motor 10 meets a use requirement. In the assembly process, dynamic balance of an entire machine introduces only one assembly error. Impact of the error can be eliminated by remaining unbalance and assembly size errors (for example parameters such as interference and coaxiality) of two rotor systems, to effective control remaining unbalance of the entire machine. In addition, in the assembly method for the disk motor 10 in embodiments of this application, assembly convenience is ensured, and quality of dynamic balance of the entire machine can be significantly improved.
The foregoing descriptions are merely specific implementations of this application, but are not intended to limit the protection scope of this application. Any variation or replacement readily figured out by a person skilled in the art within the technical scope disclosed in this application shall fall within the protection scope of this application. Therefore, the protection scope of this application shall be subject to the protection scope of the claims.
| Number | Date | Country | Kind |
|---|---|---|---|
| 202210770799.7 | Jun 2022 | CN | national |
This application is a continuation of International Application No. PCT/CN2023/084013, filed on Mar. 27, 2023, which claims priority to Chinese Patent Application No. 202210770799.7, filed on Jun. 30, 2022. The disclosures of the aforementioned applications are hereby incorporated by reference in their entireties.
| Number | Date | Country | |
|---|---|---|---|
| Parent | PCT/CN2023/084013 | Mar 2023 | WO |
| Child | 19003373 | US |