Middle axle structure for electric bicycle
By adding mounting seats on both sides of the frame of the electric bicycle and simplifying the central shaft structure, the problems of complex assembly and increased weight in the prior art are solved, and the lightweight and energy efficiency of the electric bicycle are achieved.
Patent Information
- Application Number
- CN202422462323.4
- Authority / Receiving Office
- CN · China
- Patent Type
- Utility models(China)
- Current Assignee / Owner
- Filing Date
- 2024-10-11
- Publication Date
- 2025-07-08
- Estimated Expiration
- 2034-10-11
AI Technical Summary
The central axle structure of existing electric bicycles is complex, which increases assembly difficulty and significantly increases weight, making it difficult to achieve lightweight and improve energy efficiency.
Add a left mounting seat and a right mounting seat on both sides of the electric bicycle frame, and assemble the central shaft body between them. Use the bearing installation structure and bearing components to cancel the five-way pipe bracket and directly install the central shaft to simplify the assembly process.
It has achieved simplification of the assembly structure, reduced the weight of the vehicle, met the lightweight requirements, and improved energy efficiency.
Smart Images
Figure CN223072669U_ABST
Abstract
Description
Technical Field
[0001] The utility model relates to the technical field of electric bicycle parts, in particular to a bottom bracket structure for an electric bicycle. Background Art
[0002] At present, most of the bottom brackets of electric bicycles on the market are installed by using a bottom bracket shell. The bottom bracket shell comes from bicycles and is used to connect the cross position of the seat tube, down tube and two rear stays. Plus, it is essentially a through tube, and there are a total of five directions communicating, so it is called "bottom bracket". On electric bicycles, most of the frame tubes are on both sides, while the bottom bracket shell is in the middle, and additional brackets for fixing the bottom bracket shell need to be added.
[0003] However, adding an additional bottom bracket shell not only increases the complexity of the assembly structure, but also significantly increases the weight of the whole vehicle. For the electric bicycle industry that pursues lightweight and energy efficiency improvement, this is undoubtedly a problem that needs to be overcome.
[0004] On this basis, it is a social demand to develop a bottom bracket structure for an electric bicycle. Summary of the Utility Model
[0005] The applicant of the present utility model aims at the above-mentioned disadvantages in the existing production technology, and provides a bottom bracket structure for an electric bicycle, so as to be able to reduce the overall weight on the basis of simplifying the assembly structure, realize the lightweight of the electric bicycle, and improve energy efficiency.
[0006] The technical solution adopted by the present utility model is as follows: A bottom bracket structure for an electric bicycle, a left mounting seat and a right mounting seat are added at both sides of the electric bicycle frame, and a bottom bracket body is assembled between the left mounting seat and the right mounting seat; bearing mounting structures are installed on both the left mounting seat and the right mounting seat, and bearing assemblies are arranged at the contact ends of the bearing mounting structures and the bottom bracket body; a chainring is fixed on the bottom bracket body.
[0007] As a further improvement of the above technical solution:
[0008] Preferably, the left mounting seat and the right mounting seat are of an integral structure with the electric bicycle frame;
[0009] Or, the left mounting seat and the right mounting seat are metal parts and are welded to both sides of the frame.
[0010] Preferably, on the bottom bracket body, a step is arranged at the contact end of the bearing assembly and the bottom bracket body, and the step is used for limiting the bearing assembly;
[0011] More preferably, the structure of the bearing assembly is a rolling friction structure with metal balls added in a cage or a nylon sliding friction structure without balls.
[0012] Preferably, the bearing mounting structure includes a left bearing seat and a right bearing seat. The left bearing seat is assembled on the left mounting seat, and the right bearing seat is assembled on the right mounting seat; a left bearing assembly is provided at the contact end of the left bearing seat and the central shaft body; a right bearing assembly is provided at the contact end of the right bearing seat and the central shaft body.
[0013] Preferably, threads or counterbored holes are machined on the left mounting seat; when threads are machined on the left mounting seat, the left bearing seat is screwed into the left mounting seat; when counterbored holes are machined on the left mounting seat, the left bearing seat is press-fitted into the left mounting seat, and an interference fit is provided between the left bearing seat and the left mounting seat; threads or counterbored holes are machined on the right mounting seat; when threads are machined on the right mounting seat, the right bearing seat is screwed into the right mounting seat; when counterbored holes are machined on the right mounting seat, the right bearing seat is press-fitted into the right mounting seat, and an interference fit is provided between the right bearing seat and the right mounting seat;
[0014] Alternatively, an integral structure is provided between the left bearing seat and the left mounting seat, and an integral structure is provided between the right bearing seat and the right mounting seat.
[0015] More preferably, a lock ring is added to the left bearing seat; the left bearing seat is screwed into the left mounting seat from the outside of the left mounting seat through threads, and the lock ring is screwed into the left bearing seat from the inside of the left mounting seat through threads. The lock ring is used to prevent the left bearing seat from loosening.
[0016] Preferably, the chainring is provided with an assembly hole and is fixed to the central shaft body through a locking bolt assembly passing through the assembly hole; the structure of the locking bolt assembly is: including a chainring locking bolt and a chainring locking nut sleeved on the chainring locking bolt and located on the other side of the assembly hole.
[0017] The beneficial effects of the present utility model are as follows:
[0018] The structure of the present utility model is compact and reasonable, and the assembly process is simple. The assembly structure that requires a bottom bracket to install the central shaft in the prior art is cancelled, and there is no need to additionally provide a bottom bracket support. Mounting seats are directly added on both sides of the frame, and the central shaft is directly installed by using the mounting seats, which simplifies the assembly structure, reduces the weight of the whole vehicle and the cost; at the same time, it also meets the lightweight requirements of electric bicycles and improves energy efficiency. BRIEF DESCRIPTION OF THE DRAWINGS
[0019] Figure 1 is an exploded view of the overall structure of the present utility model.
[0020] Figure 2 is a front view of the overall structure of the present utility model.
[0021] Figure 3 is Figure 2 the A-A sectional view in
[0022] Wherein: 1. Left bearing seat; 2. Left bearing assembly; 3. Middle shaft body; 4. Left mounting seat; 5. Lock ring; 6. Chainring locking nut; 7. Chainring; 8. Right bearing assembly; 9. Right bearing seat; 10. Right mounting seat; 11. Chainring locking bolt. Detailed implementation manners
[0023] The following combines with the drawings to illustrate the detailed implementation manners of the present utility model.
[0024] For the convenience of understanding the present utility model, the present utility model will be described more comprehensively below with reference to the relevant drawings. The preferred embodiments of the present utility model are given in the drawings. However, the present utility model can be implemented in many different forms and is not limited to the embodiments described herein. On the contrary, the purpose of providing these embodiments is to make the understanding of the disclosure content of the present utility model more thorough and comprehensive.
[0025] Unless otherwise defined, all technical and scientific terms used herein have the same meaning as commonly understood by those skilled in the technical field to which the present utility model belongs. The terms used in the description of the present utility model in this specification are only for the purpose of describing specific embodiments and are not intended to limit the present utility model. The term "and / or" used herein includes any and all combinations of one or more of the related listed items.
[0026] In the case of using "including", "having", and "comprising" described herein, unless a clear limiting term is used, such as "only", "consisting of", etc., another component can also be added. Unless otherwise mentioned, terms in the singular form can include the plural form and should not be understood as having a quantity of one.
[0027] It should be understood that although terms such as "first" and "second" can be used herein to describe various elements, these elements should not be limited by these terms. These terms are only used to distinguish one element from another. For example, without departing from the scope of the present utility model, the first element can be called the second element, and similarly, the second element can be called the first element.
[0028] In addition, the drawings are not drawn to a scale of 1:1, and the relative sizes of the various elements are only drawn by way of example in the drawings and not necessarily to the true scale.
[0029] As Figures 1 to 3 , it shows a state schematic diagram of a middle shaft structure for an electric bicycle in an embodiment of the present utility model; for the convenience of description, the drawings only show the structures related to the embodiments of the present utility model.
[0030] The central shaft structure for an electric bicycle in this embodiment adds a left mounting seat 4 and a right mounting seat 10 at both sides of the electric bicycle frame, and assembles a central shaft body 3 between the left mounting seat 4 and the right mounting seat 10; both the left mounting seat 4 and the right mounting seat 10 are equipped with bearing mounting structures, and bearing assemblies are provided at the contact ends of the bearing mounting structures and the central shaft body 3; a chainring 7 is fixed on the central shaft body 3.
[0031] In this embodiment, by way of example, the left mounting seat 4 and the right mounting seat 10 are of an integral structure with the electric bicycle frame.
[0032] In this embodiment, on the central shaft body 3, a step is provided at the contact end of the bearing assembly and the central shaft body 3, and the step is used to limit the bearing assembly.
[0033] In this embodiment, by way of example, the structure of the bearing assembly is a rolling friction structure with metal balls added in a cage; alternatively, the structure of the bearing assembly can also be a nylon sliding friction structure without balls.
[0034] In this embodiment, the bearing mounting structure includes a left bearing seat 1 and a right bearing seat 9. The left bearing seat 1 is assembled on the left mounting seat 4, and the right bearing seat 9 is assembled on the right mounting seat 10; a left bearing assembly 2 is provided at the contact end of the left bearing seat 1 and the central shaft body 3; a right bearing assembly 8 is provided at the contact end of the right bearing seat 9 and the central shaft body 3; by way of example, both the left bearing seat 1 and the right bearing seat 9 are set as steel bowl structures.
[0035] In this embodiment, specifically, threads are machined on the left mounting seat 4, and the left bearing seat 1 is screwed into the left mounting seat 4 through the threads; at the same time, a lock ring 5 is added on the left bearing seat 1; the left bearing seat 1 is screwed into the left mounting seat 4 from the outside of the left mounting seat 4, and the lock ring 5 is screwed into the left bearing seat 1 from the inside of the left mounting seat 4, and the lock ring 5 is used to prevent the left bearing seat 1 from loosening.
[0036] In this embodiment, specifically, a counterbore is machined on the right mounting seat 10; the right bearing seat 9 is press-fitted into the right mounting seat 10, and an interference fit is provided between the right bearing seat 9 and the right mounting seat 10.
[0037] In this embodiment, specifically, the chainring 7 is provided with assembly holes and is fixed on the central shaft body 3 through the assembly holes by a locking bolt assembly; the structure of the locking bolt assembly is: including a chainring locking bolt 11 and a chainring locking nut 6 sleeved on the chainring locking bolt 11 and located on the other side of the assembly hole.
[0038] Embodiment Two:
[0039] In this embodiment, the difference from Embodiment One is that the left mounting seat 4 and the right mounting seat 10 are metal parts and are welded to both sides of the frame.
[0040] Embodiment Three:
[0041] In this embodiment, the difference from Embodiment One is as follows: a counterbore is machined on the left mounting seat 4, and the left bearing seat 1 is press-fitted into the left mounting seat 4; a thread is machined on the right mounting seat 10, and the right bearing seat 9 is screwed into the right mounting seat 10 through the thread.
[0042] Embodiment Four:
[0043] In this embodiment, the difference from Embodiment One is as follows: threads are machined on both the left mounting seat 4 and the right mounting seat 10, and the bearing seat is assembled with the corresponding mounting seat through the threads.
[0044] Embodiment Five:
[0045] In this embodiment, the difference from Embodiment One is as follows: counterbores are machined on both the left mounting seat 4 and the right mounting seat 10, and the bearing seat is inserted into the corresponding mounting seat through the counterbore and interference-fitted.
[0046] Embodiment Six:
[0047] In this embodiment, the difference from Embodiment One is as follows: the left bearing seat 1 and the left mounting seat 4 are of an integral structure, and the right bearing seat 9 and the right mounting seat 10 are of an integral structure;
[0048] In this embodiment, the bearing seat and the corresponding mounting seat are directly integrated, so that the mounting seat itself has the function of the bearing seat without the need to additionally assemble bearing seat parts, further simplifying the assembly process.
[0049] The structure of the present utility model is reasonable and the assembly is simple. Mounting seats are directly added on both sides of the frame of the electric bicycle, and the central shaft body 3 is directly mounted by using the mounting seats, which simplifies the assembly structure, reduces the weight of the whole vehicle and the cost; at the same time, it also meets the lightweight requirements of the electric bicycle and improves the energy efficiency.
[0050] The technical features of the above-described embodiments can be combined arbitrarily. For the sake of brevity of description, not all possible combinations of the technical features in the above embodiments are described. However, as long as there is no contradiction in the combination of these technical features, it should be considered as the scope recorded in this specification.
[0051] The above-described embodiments only represent the implementation manners of the present utility model. The description is relatively specific and detailed, but it should not be construed as a limitation on the scope of the utility model patent. It should be noted that for those of ordinary skill in the art, without departing from the concept of the present utility model, several deformations and improvements can still be made, and these all belong to the protection scope of the present utility model. Therefore, the protection scope of the utility model patent should be subject to the appended claims.
Claims
1. A central shaft structure for an electric bicycle, characterized in that: Left mounting seats (4) and right mounting seats (10) are additionally provided at both sides of the electric bicycle frame, and a central shaft body (3) is assembled between the left mounting seat (4) and the right mounting seat (10); Both the left mounting seat (4) and the right mounting seat (10) have bearing mounting structures, and bearing assemblies are arranged at the contact ends of the bearing mounting structures and the central shaft body (3); A chainring (7) is fixed on the central shaft body (3).
2. The bottom bracket structure for an electric bicycle according to claim 1, characterized in that: The left mounting seat (4) and the right mounting seat (10) are of an integral structure with the electric bicycle frame.
3. The bottom bracket structure for an electric bicycle according to claim 1, wherein: The left mounting seat (4) and the right mounting seat (10) are metal parts and are welded to both sides of the frame.
4. The bottom bracket structure for an electric bicycle according to claim 1, wherein: On the central shaft body (3), a step is arranged at the contact end of the bearing assembly and the central shaft body (3), and the step is used for limiting the bearing assembly.
5. The bottom bracket structure for an electric bicycle according to claim 4, characterized in that: The structure of the bearing assembly is a rolling friction structure with metal balls added in a cage or a nylon sliding friction structure without balls.
6. The bottom bracket structure for an electric bicycle according to claim 1, wherein: The bearing mounting structure includes a left bearing seat (1) and a right bearing seat (9). The left bearing seat (1) is assembled on the left mounting seat (4), and the right bearing seat (9) is assembled on the right mounting seat (10); A left bearing assembly (2) is arranged at the contact end of the left bearing seat (1) and the central shaft body (3); A right bearing assembly (8) is arranged at the contact end of the right bearing seat (9) and the central shaft body (3).
7. The bottom bracket structure for an electric bicycle according to claim 6, wherein: Threads are machined or counterbored holes are machined on the left mounting seat (4); when threads are machined on the left mounting seat (4), the left bearing seat (1) is screwed into the left mounting seat (4); when counterbored holes are machined on the left mounting seat (4), the left bearing seat (1) is press-fitted into the left mounting seat (4), and an interference fit is formed between the left bearing seat (1) and the left mounting seat (4); Threads are machined or counterbored holes are machined on the right mounting seat (10); when threads are machined on the right mounting seat (10), the right bearing seat (9) is screwed into the right mounting seat (10); when counterbored holes are machined on the right mounting seat (10), the right bearing seat (9) is press-fitted into the right mounting seat (10), and an interference fit is formed between the right bearing seat (9) and the right mounting seat (10).
8. The bottom bracket structure for an electric bicycle according to claim 6, characterized in that: The left bearing seat (1) and the left mounting seat (4) are of an integral structure, and the right bearing seat (9) and the right mounting seat (10) are of an integral structure.
9. The bottom bracket structure for an electric bicycle according to claim 7, characterized in that: A lock ring (5) is additionally arranged on the left bearing seat (1); The left bearing seat (1) is screwed into the left mounting seat (4) from the outside of the left mounting seat (4) through threads, and the lock ring (5) is screwed into the left bearing seat (1) from the inside of the left mounting seat (4) through threads. The lock ring (5) is used to prevent the left bearing seat (1) from loosening.
10. The bottom bracket structure for an electric bicycle according to claim 1, characterized in that: Assembly holes are arranged on the chainring (7), and the chainring is fixed on the central shaft body (3) through a locking bolt assembly passing through the assembly holes; The structure of the locking bolt assembly is: including a chainring locking bolt (11) and a chainring locking nut (6) sleeved on the chainring locking bolt (11) and located on the other side of the assembly hole.