Middle motor and middle transmission
By using bearings at both ends of the shaft to support the planetary gear mechanism, the instability issue in middle motor designs is resolved, enhancing stability and performance.
Patent Information
- Application Number
- CN202422138241.4
- Authority / Receiving Office
- CN · China
- Patent Type
- Utility models(China)
- Current Assignee / Owner
- Filing Date
- 2024-09-02
- Publication Date
- 2025-07-15
- Estimated Expiration
- 2034-09-02
AI Technical Summary
The shaft of the existing mid-mounted motor has poor stability due to cantilever problems.
The first bearing and the second bearing are respectively installed at both ends of the shaft of the center motor, and the planetary gear assembly is mounted on the shaft and between the first bearing and the second bearing, and is mounted on the other assembly through these two bearings, thereby balanced both ends of the shaft.
Through the support of the bearing, the cantilever problem of the shaft is solved, the stability of the mid-mounted motor is improved, and the volume of the mid-mounted motor is reduced through a compact structural design.
Smart Images
Figure CN223109819U_ABST
Abstract
Description
Technical Field
[0001] The utility model relates to the technical field of motors, in particular to a mid-mounted motor and a mid-mounted transmission. Background Art
[0002] In an electric assist bicycle equipped with a transmission, a mid-mounted motor drives the output component of the transmission to rotate to provide power for the bicycle, enabling the user to ride more effortlessly. In existing mid-mounted motors, generally, a reduction component (such as a planetary gear system) is installed at one end of the shaft of the mid-mounted motor, and the shaft drives the reduction component to rotate. This design will leave the other end of the shaft unsupported, resulting in a cantilever problem of the shaft and thus affecting the stability of the mid-mounted motor. Summary of the Utility Model
[0003] The purpose of the utility model is to provide a mid-mounted motor and a mid-mounted transmission, aiming to solve the problem of the cantilever of the shaft of the mid-mounted motor in the prior art.
[0004] In a first aspect, the present application provides a mid-mounted motor, including: a shaft, a first bearing, a core, a reduction component, and a second bearing; the core includes a rotor and a stator located outside the rotor, and the reduction component includes a planetary gear assembly and a ring gear located outside the planetary gear assembly; the first bearing, the rotor, the planetary gear assembly, and the second bearing are sequentially installed on the shaft along the axial direction, and the stator and the ring gear are relatively fixed; the shaft is used to rotate under the drive of the rotor, and then drive the planetary gear assembly to rotate.
[0005] In an embodiment, the planetary gear assembly includes multiple groups of planetary gear combinations, the multiple groups of planetary gear combinations share one ring gear, and each group of planetary gear combinations includes multiple planetary gears.
[0006] In an embodiment, the planetary gear assembly includes a sun gear installed on the shaft, multiple first planetary gears meshing with the sun gear, a first planetary carrier for installing the first planetary gears, multiple second planetary gears driven to rotate under the drive of the first planetary carrier, and a second planetary carrier for installing the second planetary gears; the multiple first planetary gears and the multiple second planetary gears are both meshed with the ring gear.
[0007] In an embodiment, the first planetary carrier includes a first planetary carrier body and a first output portion protruding from one end of the first planetary carrier body, and the second planetary carrier includes a second planetary carrier body and a second output portion protruding from one end of the second planetary carrier body; the second planetary carrier body is sleeved on the first output portion, and a third bearing in contact with the second planetary carrier body is installed on the first output portion.
[0008] In one embodiment, a fourth bearing that abuts against the second output portion is mounted on the shaft.
[0009] In one embodiment, the sun gear is a helical gear.
[0010] In one embodiment, the mid-mounted motor further includes an output gear mounted on the second planet carrier.
[0011] In one embodiment, the mid-mounted motor further includes a one-way clutch assembly mounted inside the output gear and cooperating with the outside of the second planet carrier, and the output gear is used to lock or disengage from the second planet carrier through the one-way clutch assembly.
[0012] In one embodiment, the stator is provided with a first mounting portion for fixing in the housing where the mid-mounted motor is located, and the ring gear is provided with a second mounting portion for fixing in the housing.
[0013] In a second aspect, the present application provides a mid-mounted transmission, including a housing, a transmission assembly, and the mid-mounted motor as described in the first aspect above, and the transmission assembly and the mid-mounted motor are located inside the housing.
[0014] The beneficial effects of the mid-mounted motor provided by the present utility model are as follows: By respectively mounting a first bearing and a second bearing at both ends of the shaft of the mid-mounted motor, and mounting the planetary gear assembly on the shaft and between the first bearing and the second bearing, the mid-mounted motor is mounted on other components (such as a housing) through the first bearing and the second bearing, which can enable both the first bearing and the second bearing to play a role in supporting the shaft, balance the forces at both ends of the shaft, and solve the problem of the shaft's cantilever. BRIEF DESCRIPTION OF THE DRAWINGS
[0015] In order to more clearly illustrate the technical solutions in the embodiments of the present utility model, the following will briefly introduce the drawings required for use in the embodiments or the description of the prior art.
[0016] Figure 1 Schematic diagram of the mid-mounted motor provided by the embodiment of the present utility model;
[0017] Figure 2 Cross-sectional view of the mid-mounted motor provided by the embodiment of the present utility model;
[0018] Figure 3 Partial exploded view of the mid-mounted motor provided by the embodiment of the present utility model.
[0019] Among them, the reference numerals in the drawings are as follows:
[0020] 10. Shaft; 20. First bearing; 30. Movement; 31. Rotor; 32. Stator; 40. Reduction assembly; 41. Planetary gear assembly; 411. Sun gear; 412. First planetary gear; 413. First planet carrier; 4131. First planet carrier body; 4132. First output part; 414. Second planetary gear; 415. Second planet carrier; 4151. Second planet carrier body; 4152. Second output part; 42. Ring gear; 50. Second bearing; 60. Third bearing; 70. Fourth bearing; 80. Fifth bearing; 90. Output gear; 91. One-way clutch assembly; 911. Cage; 912. Roller. Detailed implementation mode
[0021] The embodiments of the present invention will be described in detail below. The examples of the embodiments are shown in the drawings, where the same or similar reference numerals denote the same or similar elements or elements having the same or similar functions throughout. The embodiments described below by referring to the drawings are exemplary and are intended to explain the present invention and should not be construed as a limitation to the present invention.
[0022] Referring to "one embodiment" or "embodiments" throughout the specification means that a particular feature, structure, or characteristic described in connection with the embodiments is included in at least one embodiment of the present application. Thus, the phrases "in one embodiment" or "in some embodiments" appearing throughout the specification do not necessarily refer to the same embodiment. In addition, in one or more embodiments, the particular features, structures, or characteristics may be combined in any suitable manner.
[0023] In the description of the present invention, it should be understood that the orientation or positional relationships indicated by the terms "length", "width", "upper", "lower", "front", "rear", "left", "right", "vertical", "horizontal", "top", "bottom", "inner", "outer", etc. are based on the orientation or positional relationships shown in the drawings, and are only for the convenience of describing the present invention and simplifying the description, rather than indicating or implying that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and thus should not be construed as a limitation to the present invention.
[0024] In addition, the terms "first" and "second" are only used for descriptive purposes and should not be construed as indicating or implying relative importance or implicitly indicating the quantity of the indicated technical features. Thus, the features defined with "first" and "second" may explicitly or implicitly include one or more of such features.
[0025] In the present utility model, unless otherwise clearly defined and limited, terms such as "installation", "connection", "linkage", "fixation", etc. shall be understood in a broad sense. For example, it may be a fixed connection, a detachable connection, or an integral body; it may be a mechanical connection or an electrical connection; it may be a direct connection or an indirect connection through an intermediate medium, and it may be the internal communication between two components or the interaction relationship between two components. For those of ordinary skill in the art, the specific meanings of the above terms in the present utility model can be understood according to specific circumstances.
[0026] Please refer to Figures 1-3 , and now the mid-mounted motor in the embodiments of the present utility model will be described.
[0027] The mid-mounted motor in the embodiments of the present utility model includes a shaft 10, a first bearing 20, a motor core 30, a reduction assembly 40, and a second bearing 50; the motor core 30 includes a rotor 31 and a stator 32 located outside the rotor 31, and the reduction assembly 40 includes a planetary gear assembly 41 and a gear ring 42 located outside the planetary gear assembly 41; the first bearing 20, the rotor 31, the planetary gear assembly 41, and the second bearing 50 are sequentially installed on the shaft 10 along the axial direction, and the stator 32 and the gear ring 42 are relatively fixed; wherein, the axial direction is referenced by the axial direction of the shaft 10. The shaft 10 is used to rotate under the drive of the rotor 31, and then drive the planetary gear assembly 41 to rotate. Among them, the first bearing 20 and the second bearing 50 may be rolling bearings. The mid-mounted motor is installed on other components (such as the housing where the mid-mounted motor is located) through the first bearing 20 and the second bearing 50 at both ends.
[0028] In the above embodiment, by sequentially installing the first bearing 20, the rotor 31, the planetary gear assembly 41, and the second bearing 50 on the shaft 10, the first bearing 20 and the second bearing 50 are located at both ends of the shaft 10, so that the mid-mounted can be installed on other components through the first bearing 20 and the second bearing 50, and both the first bearing 20 and the second bearing 50 play a role in supporting the shaft 10, so that the forces at both ends of the shaft 10 are balanced, solving the overhang problem of the shaft 10, and further improving the stability during the operation of the mid-mounted motor.
[0029] In one embodiment, the planetary gear assembly 41 includes multiple groups of planetary gear combinations, and the multiple groups of planetary gear combinations share a gear ring 42. Each group of planetary gear combinations includes multiple planetary gears, so that the occupied space of the gear ring 42 can be reduced, and further the volume of the mid-mounted motor can be reduced.
[0030] In one embodiment, the planetary gear assembly 41 includes a sun gear 411 mounted on the shaft 10, a plurality of first planetary gears 412 meshing with the sun gear 411, a first planetary carrier 413 for mounting the first planetary gears 412, a plurality of second planetary gears 414 driven to rotate by the first planetary carrier 413, and a second planetary carrier 415 for mounting the second planetary gears 414; the plurality of first planetary gears 412 and the plurality of second planetary gears 414 both mesh with the ring gear 42. When the shaft 10 rotates driven by the rotor 31, the sun gear 411 is driven to rotate. The rotation of the sun gear 411 drives the plurality of first planetary gears 412 to rotate around the sun gear 411 within the ring gear 42. The first planetary gears 412 drive the first planetary carrier 413 to rotate, the first planetary carrier 413 drives the plurality of second planetary gears 414 to rotate, and the second planetary gears 414 then drive the second planetary carrier 415 to rotate. The second planetary carrier 415 transmits the driving force to the transmission. Through the above structural design, the reduction ratio of the reduction assembly 40 can be increased, and the structure of the reduction assembly 40 can be made more compact, thereby reducing the volume of the mid-mounted motor.
[0031] In one embodiment, the first planetary carrier 413 includes a first planetary carrier body 4131 and a first output portion 4132 protruding from one end of the first planetary carrier body 4131, and the second planetary carrier 415 includes a second planetary carrier body 4151 and a second output portion 4152 protruding from one end of the second planetary carrier body 4151; the second planetary carrier body 4151 is sleeved on the first output portion 4132, and a third bearing 60 in contact with the second planetary carrier body 4151 is mounted on the first output portion 4132. Exemplarily, the first output portion 4132 includes an engaging portion and a bearing mounting portion connected to each other. The outer side of the engaging portion meshes with the plurality of second planetary gears 414 to drive the plurality of second planetary gears 414 to rotate, and the third bearing 60 is mounted on the bearing mounting portion. By mounting the third bearing 60, the stability between the first planetary carrier 413 and the second planetary carrier 415 can be increased.
[0032] In one embodiment, a fourth bearing 70 in contact with the second output portion 4152 is mounted on the shaft 10, so as to improve the stability of the second planetary carrier 415 during rotation.
[0033] In one embodiment, a fifth bearing 80 in contact with the first output portion 4132 is mounted on the shaft 10, so as to increase the stability of the first planetary carrier 413 during rotation.
[0034] In one embodiment, the sun gear 411 is a helical gear, so as to increase the reduction ratio of the reduction assembly 40.
[0035] In one embodiment, the mid-mounted motor further includes an output gear 90 mounted on the second planet carrier 415, so as to drive the rotation of a gear meshing with the output gear 90 through the output gear 90.
[0036] In one embodiment, the mid-mounted motor further includes a one-way clutch assembly 91 mounted inside the output gear 90 and cooperating with the outer side of the second planet carrier 415. The output gear 90 is used to lock or separate from the second planet carrier 415 through the one-way clutch assembly 91. Exemplarily, the one-way clutch assembly 91 includes a cage 911 and rollers 912. A groove is provided on the outer side of the second output portion 4152, so as to form a receiving groove between the outer side of the second output portion 4152 and the cage 911. The rollers 912 are located in the receiving groove. When the second planet carrier 415 rotates, the rollers 912 move towards the side away from the groove in the receiving groove, and the second planet carrier 415 and the output gear 90 are combined into a whole through the rollers 912, and the output gear 90 rotates synchronously with the second planet carrier 415. When the second planet carrier 415 stops rotating, the rollers 912 move into the groove in the receiving groove, and the second planet carrier 415 is separated from the output gear 90. Through the one-way clutch assembly 91, the output gear 90 can be locked or separated from the second planet carrier 415, so that the output gear 90 can rotate driven by the movement mechanism 30 or can also rotate driven by other driving components.
[0037] In another embodiment, the outer side of the second output portion 4152 of the second planet carrier 415 can directly mesh with other gears to drive the rotation of other gears.
[0038] In one embodiment, a first mounting portion for fixing in the housing where the mid-mounted motor is located is provided on the stator 32, and a second mounting portion for fixing in the housing is provided on the ring gear 42, so that both the stator 32 and the ring gear 42 can be fixed in the housing, and the stator 32 and the ring gear 42 are relatively fixed axially and circumferentially.
[0039] Another embodiment of the present application provides a mid-mounted transmission, including a housing, a transmission assembly, and the above-mentioned mid-mounted motor. The transmission assembly and the mid-mounted motor are located in the housing.
[0040] The above are only the preferred embodiments of the present invention, and are not intended to limit the present invention. Any modifications, equivalent replacements, and improvements made within the spirit and principle of the present invention should be included in the protection scope of the present invention.
Claims
1. A mid-mounted motor, characterized in that, include: A shaft, a first bearing, a movement, a reduction assembly and a second bearing; the movement includes a rotor and a stator located outside the rotor, and the reduction assembly includes a planetary gear assembly and a ring gear located outside the planetary gear assembly; the first bearing, the rotor, the planetary gear assembly and the second bearing are sequentially installed on the shaft along the axial direction, and the stator and the ring gear are relatively fixed; the shaft is used to rotate under the drive of the rotor, thereby driving the planetary gear assembly to rotate.
2. The mid-mounted motor according to claim 1, wherein The planetary gear assembly includes a plurality of planetary gear assemblies, the plurality of planetary gear assemblies share one ring gear, and each of the planetary gear assemblies includes a plurality of planetary gears.
3. The mid-mounted motor according to claim 2, characterized in that, The planetary gear assembly includes a sun gear mounted on the shaft, a plurality of first planetary gears meshing with the sun gear, a first planet carrier for mounting the first planetary gears, a plurality of second planetary gears for rotating under the drive of the first planet carrier, and a second planet carrier for mounting the second planetary gears; the plurality of first planetary gears and the plurality of second planetary gears are all meshed with the ring gear.
4. The mid-mounted motor according to claim 3, wherein The first planet carrier includes a first planet carrier body and a first output part protruding from one end of the first planet carrier body, and the second planet carrier includes a second planet carrier body and a second output part protruding from one end of the second planet carrier body; the second planet carrier body is sleeved on the first output part, and the first output part is equipped with a third bearing that contacts the second planet carrier body.
5. The mid-mounted motor according to claim 4, characterized in that, A fourth bearing abutting against the second output portion is mounted on the shaft.
6. The mid-mounted motor according to claim 3, characterized in that The sun gear is a helical gear.
7. The mid-mounted motor according to claim 3, characterized in that, The mid-mounted motor also includes an output gear mounted on the second planet carrier.
8. The mid-mounted motor according to claim 7, characterized in that, The mid-mounted motor further includes a one-way clutch assembly installed on the inner side of the output gear and matched with the outer side of the second planet carrier. The output gear is used to be locked or separated from the second planet carrier through the one-way clutch assembly.
9. The mid-mounted motor according to claim 1, wherein, The stator is provided with a first mounting portion for fixing in a housing where the central motor is located, and the ring gear is provided with a second mounting portion for fixing in the housing.
10. A mid-mounted transmission, characterized in that, It comprises a housing, a transmission assembly and a mid-mounted motor as claimed in any one of claims 1 to 9, wherein the transmission assembly and the mid-mounted motor are located in the housing.