CN210822593U

CN210822593U - Middle shaft connecting structure of electric bicycle

Info

Publication number: CN210822593U
Application number: CN201921642791.2U
Authority: CN
Inventors: 倪捷; 王云; 朱业良
Original assignee: BOE Technology Group Co Ltd
Current assignee: BOE Technology Group Co Ltd; Zhejiang Luyuan Electric Vehicle Co Ltd
Priority date: 2019-09-29
Filing date: 2019-09-29
Publication date: 2020-06-23
Anticipated expiration: 2029-09-29

Abstract

The utility model discloses an electric bicycle's axis connection structure, including axis, frame low tube, five-way portion, the axis is located in the five-way portion, the frame low tube is connected in the five-way portion, five-way portion both ends are equipped with the extension respectively, five-way portion is the tubulose and forms cylindric accommodation space inside it, the axis is located in the accommodation space, the cross-section of five-way portion axis direction is the interior protruding step form of centre, five-way portion is greater than or equal to along the length of axis direction frame low tube bore. The utility model discloses set up the extension at the both ends of five-way portion, can be better be connected with the frame low tube of bigger bore, and no longer need carry out draw processing or flatten the processing to the frame low tube, reduced the processing degree of difficulty, practiced thrift the cost.

Description

Middle shaft connecting structure of electric bicycle

Technical Field

The utility model relates to an electric bicycle especially relates to an electric bicycle's well hub connection structure.

Background

The continuous development of electric bicycles has the increasing demand on the structure of the built-in battery of the frame lower tube and the increasing demand on the battery capacity, so that the caliber of the frame lower tube is gradually increased along with the battery capacity. The frame lower tube is connected on the axis through the five-way pipe, but the axis is the standard part, and axis assembly size relates to the collocation of bicycle transmission and speed change system size, therefore the axis size can't change, leads to the frame lower tube after the bore grow can't carry out effectual connection in the axis, and the current scheme is all to frame lower tube draw processing or flatten the processing, and the processing degree of difficulty is big, and the outward appearance is not pleasing to the eye, increases the cost. If the complex cross-section is more difficult to machine, it is only an option to forego use and improvements need to be made to this.

Disclosure of Invention

The utility model discloses thereby to the mode that prior art exists to frame low tube carry out draw processing or flatten processing and axis connection, the processing degree of difficulty is big, defect such as with high costs provides an electric bicycle's well hub connection structure.

In order to solve the technical problem, the utility model discloses a following technical scheme realizes:

a middle shaft connecting structure of an electric bicycle comprises a middle shaft, a frame lower pipe and a five-way portion, wherein the middle shaft is located in the five-way portion, the frame lower pipe is connected to the five-way portion, extending portions are arranged at two ends of the five-way portion respectively, the five-way portion is tubular, a cylindrical accommodating space is formed inside the five-way portion, the middle shaft is arranged in the accommodating space, the cross section of the five-way portion in the axial direction is of a step shape with an inward convex middle portion, and the length of the five-way portion in the axial direction is larger than or equal to the caliber of the frame lower pipe.

The extension parts are arranged at the two ends of the five-way part, the frame lower pipe with a larger caliber can be better connected, the frame lower pipe does not need to be subjected to pipe reducing processing or flattening processing, the processing difficulty is reduced, the cost is saved, the containing space is used for containing the center shaft, the center shaft is stably connected to the five-way part, the length of the five-way part along the axial direction is larger than or equal to the caliber of the frame lower pipe, enough connecting space can be provided for the frame lower pipe, and the frame lower pipe is more stably connected with the five-way part.

Preferably, in the above central shaft connecting structure of the electric bicycle, fixing spaces with the same radius are arranged at two ends of the accommodating space, and the radius of the accommodating space is smaller than that of the fixing spaces.

The radius of the fixed space arranged at the two ends of the accommodating space is larger than that of the accommodating space, so that the process of mounting or dismounting the middle shaft is more convenient.

Preferably, in the above middle shaft connecting structure of the electric bicycle, both ends of the accommodating space are provided with internal threads, and the middle shaft is connected to the five-way portion through the internal threads of the accommodating space.

The internal thread is arranged in the accommodating space, so that the connection between the middle shaft and the accommodating space is facilitated, and the connection stability is improved.

Preferably, the center shaft connecting structure of the electric bicycle further comprises two locking sleeves, the two locking sleeves are arranged on the center shaft and are in threaded connection with the accommodating space, the locking sleeves are provided with outer end portions, and the outer end portions are located in the fixing space and limited by the fixing space.

The locking sleeves are arranged at the two ends of the accommodating space, the outer end parts of the locking sleeves are located in the fixing space, the position of the middle shaft can be better limited, and meanwhile, the installation and the disassembly processes of the middle shaft are more convenient and faster.

Preferably, in the above-mentioned intermediate shaft connecting structure of an electric bicycle, the five-way portion includes an inner tube and a sleeve, the length of the sleeve is greater than the length of the inner tube, the sleeve is sleeved outside the inner tube, and the sleeve is longer than the inner tube to form the extension portion.

The extension part is formed by matching the sleeve with the inner pipe, the utilization rate of the inner pipe can be improved, the production cost is reduced, the matching of the sleeve and the inner pipe is low in processing difficulty, the length of the extension part is convenient to adjust, and therefore the extension part can be better connected with the lower tubes of the frames with different calibers, and the adaptability of each part is improved.

Preferably, in the above middle axle connecting structure for the electric bicycle, the frame lower tube is welded to the outer surface of the sleeve, and the middle axle is disposed in the inner tube.

The inner pipe is matched with the middle shaft, the inner pipe can be correspondingly adjusted according to the standard of the middle shaft, the sleeve pipe is matched with the frame lower pipe, the sleeve pipe can be correspondingly adjusted according to the size change of the frame lower pipe, and the sleeve pipe and the frame lower pipe are matched to be capable of adapting to the connection of the middle shaft and the frame lower pipes with different sizes.

Preferably, in the above-described intermediate shaft connecting structure of an electric bicycle, the sleeve is welded to an outer surface of the inner tube.

Adopt welded mode, can make sleeve pipe and inner tube connection more firm, and the operation degree of difficulty is low.

Preferably, in the above-mentioned middle shaft connecting structure of an electric bicycle, the length of the extending portion is 4-5 mm.

The length of the extension part is set to be 4-5mm, so that the extension part can be suitable for the size of most of the existing frame lower tubes, and the universality of the five-way part is improved.

Drawings

FIG. 1 is a cross-sectional view of the five-way section of the present invention;

FIG. 2 is a sectional view of the bottom bracket of the present invention;

fig. 3 is a schematic structural diagram of the present invention.

Detailed Description

The invention will be described in further detail with reference to the accompanying figures 1-3 and the detailed description, but they are not intended to limit the invention:

example 1

As shown in fig. 1 to 3, a bottom bracket connecting structure of an electric bicycle includes a bottom bracket 5, a bottom bracket tube 7, and a bottom bracket portion 2, wherein the bottom bracket tube 5 is located in the bottom bracket portion 2, the bottom bracket tube 7 is connected to the bottom bracket portion 2, two ends of the bottom bracket portion 2 are respectively provided with an extension portion 1, the bottom bracket portion 2 is tubular and forms a cylindrical accommodating space 3 therein, the bottom bracket tube 5 is located in the accommodating space 3, a cross section of the bottom bracket portion 2 in an axial direction is in a step shape with an inward convex middle, and a length of the bottom bracket portion 2 in the axial direction is greater than or equal to a diameter of the bottom bracket tube 7.

When the bottom bracket is installed, the lower frame tube 7 is firstly connected to the outer surfaces of the five-way part 2 and the extension part 1, the lower frame tube 7 and the five-way part 2 are welded, the length of the extension part 1 can be adjusted to adapt to the assembly of the lower frame tubes 7 with different sizes and calibers, and then the middle shaft 5 is installed in the accommodating space 3 to connect the middle shaft 5 and the five-way part 2. When the length of the extension part 1 along the axial direction is changed, the protruding size of the step with the cross section in the axial direction of the five-way part (2) being inwards convex in the middle is fixed and unchanged, so that the five-way part can be used as a center shaft of a standard part, and the matching requirement of the size of a bicycle transmission and speed change system related to the assembly size of the center shaft is met.

Preferably, the two ends of the accommodating space 3 are provided with fixing spaces 4 with the same radius, and the radius of the accommodating space 3 is smaller than that of the fixing spaces 4.

Preferably, both ends of the accommodating space 3 are provided with internal threads 31, and the middle shaft 5 is connected in the five-way portion 2 through the internal threads 31 of the accommodating space 3.

Preferably, the locking device further comprises two locking sleeves 6, the locking sleeves 6 are arranged on the middle shaft 5 and connected with the internal threads 31 of the accommodating space 3, the locking sleeves 6 are provided with outer end parts 61, and the outer end parts 61 are located in the fixing space 4 and limited by the fixing space 4.

Preferably, the five-way portion 2 comprises an inner tube 21 and a sleeve 22, the length of the sleeve 22 is greater than that of the inner tube 21, the sleeve 22 is sleeved outside the inner tube 21, and the extension portion 1 is formed by the sleeve 22 which is longer than the inner tube 21.

Preferably, the down tube 7 is welded to the outer surface of the sleeve 22, and the bottom bracket 5 is disposed in the inner tube 21.

Preferably, the sleeve 22 is welded to the outer surface of the inner tube 21.

Preferably, the extension 1 has a length of 4 to 5 mm.

More specifically, the five-way portion 2 is first machined, and the size and length of the inner tube 21 are determined according to the size of the bottom bracket 5, and the size and length of the bushing 22 are determined according to the sizes of the down tube 7 and the inner tube 21. After the above operation is completed, female screws 31 are formed at both ends of the inner surface of the inner tube 21, and the outer surface of the inner tube 21 is welded to the inner surface of the sleeve 22 to form the five-way portion 2. Then, the down tube 7 is welded to the outer surface of the sleeve 22 of the bottom bracket 2. Finally, the middle shaft 5 is connected inside the inner tube 21, the locking sleeves 6 are respectively connected to the internal threads 31 at the two ends of the inner tube 21, the middle shaft 5 is limited in the accommodating space 3, and meanwhile, the outer end portions 61 of the locking sleeves 6 are located in the fixing space 4, and machining is completed.

In short, the above description is only a preferred embodiment of the present invention, and all the equivalent changes and modifications made within the scope of the claims of the present invention should be covered by the present invention.

Claims

1. The utility model provides an electric bicycle's well hub connection structure, includes axis (5), frame low tube (7), five-way portion (2), axis (5) are located in five-way portion (2), frame low tube (7) are connected on five-way portion (2), its characterized in that: extension parts (1) are respectively arranged at two ends of the five-way part (2), the five-way part (2) is tubular, a cylindrical accommodating space (3) is formed in the five-way part, the middle shaft (5) is arranged in the accommodating space (3), the cross section of the five-way part (2) in the axis direction is of a step shape with an inward convex middle part, and the length of the five-way part (2) in the axis direction is larger than or equal to the caliber of the lower frame tube (7).

2. The intermediate shaft coupling structure of an electric bicycle according to claim 1, wherein: the two ends of the accommodating space (3) are provided with fixing spaces (4) with the same radius, and the radius of the accommodating space (3) is smaller than the fixing spaces (4).

3. The intermediate shaft coupling structure of an electric bicycle according to claim 2, wherein: the two ends of the accommodating space (3) are provided with internal threads (31), and the middle shaft (5) is connected into the five-way portion (2) through the internal threads (31) of the accommodating space (3).

4. The intermediate shaft coupling structure of the electric bicycle according to claim 3, wherein: the locking device is characterized by further comprising two locking sleeves (6), wherein the locking sleeves (6) are arranged on the middle shaft (5) and connected with the inner threads (31) of the accommodating space (3), outer end portions (61) are arranged on the locking sleeves (6), and the outer end portions (61) are located in the fixing space (4) and limited by the fixing space (4).

5. The intermediate shaft coupling structure of an electric bicycle according to claim 1, wherein: the five-way portion (2) comprises an inner tube (21) and a sleeve (22), the length of the sleeve (22) is larger than that of the inner tube (21), the sleeve (22) is sleeved on the outer side of the inner tube (21), and the part, longer than the inner tube (21), of the sleeve (22) forms the extension portion (1).

6. The intermediate shaft coupling structure of an electric bicycle according to claim 5, wherein: the frame lower pipe (7) is welded with the outer surface of the sleeve (22), and the middle shaft (5) is arranged in the inner pipe (21).

7. The intermediate shaft coupling structure of an electric bicycle according to claim 5, wherein: the sleeve (22) is welded on the outer surface of the inner pipe (21).

8. The intermediate shaft coupling structure of an electric bicycle according to claim 1, wherein: the length of the extension part (1) is 4-5 mm.