An electrically assisted bicycle frame produced by squeeze casting

Abstract

The application relates to the technical field of frame equipment, in particular to an extrusion-cast electric power-assisted vehicle frame which comprises a frame upper part and a frame lower part, the frame upper part is fixedly installed at the top of the frame lower part, an upper pipe is fixedly installed in the frame upper part, a lower pipe is fixedly connected to one end of the upper pipe, a middle pipe is fixedly connected to the other end of the upper pipe, a head pipe is fixedly connected to the top center of the lower pipe, first nut columns are uniformly fixedly connected to the bottom surface of the upper pipe, a frame right part is fixedly installed in the frame lower part, and a frame left part is fixedly connected to the side surface of the frame right part. The frame is composed of only three modules, so that the number of parts is small, the working procedure is few, welding is not needed, the number of workers is small, the work efficiency is high, the labor productivity is high, the product consistency is good, the quality is greatly improved, the workload of after-sales is reduced, unnecessary expenses are reduced, the cost expenditure is reduced, and carbon emission is reduced.

Description

Technical Field

[0001] This invention relates to the field of vehicle frame equipment technology, specifically to an extrusion-cast electric bicycle frame. Background Technology

[0002] According to Chinese Patent No. CN201921722845.6, this utility model discloses an electric-assisted bicycle frame, characterized by mainly comprising: a bottom bracket, a front frame, a rear frame, a rear seat plate, and a folding component; wherein, the rear frame is fixed to the bottom of the bottom bracket, the front frame adopts a double-tube structure and is connected to the bottom bracket via the folding component; the rear seat plate is welded to the bottom bracket and connected to the rear seat plate via a support tube. This utility model, by adopting a double-tube structure design for the front frame, effectively reduces the buffering force during use and increases the impact resistance; the use of the folding component makes it more convenient to use, giving this utility model the characteristics of simple structure, light weight, effective reduction of buffering force, and enhanced impact resistance.

[0003] According to Chinese Patent No. CN201720625909.5, this utility model discloses an electric-assisted bicycle frame, including a front triangle and a rear triangle. The front triangle sequentially includes tubular components of a seat tube, top tube, bottom tube, and head tube. The rear triangle sequentially includes two rear upper forks integrally connected to the seat tube and two rear lower forks integrally connected to the bottom tube. The bottom tube houses a battery. The front end of the head tube has a headlight, and the rear end of the seat tube has a taillight. The top tube houses a control panel, and the upper end of the seat tube has a seat post mounting groove. A rear fender fixing tube is located between the two rear upper forks. This utility model improves existing bicycle frames to suit electric-assisted bicycles by mounting a battery, front and rear lights, and a control panel on the frame tubes, providing a reasonably structured and functionally complete electric-assisted bicycle frame with excellent adaptability to electric-assisted bicycles. However, this patent has many processes and parts, resulting in poor consistency after processing, poor quality, and a high rework rate, requiring improvement.

[0004] The frame of an electric-assisted bicycle is a crucial component, primarily serving a load-bearing function. Its quality directly impacts user safety. However, existing electric-assisted bicycle frames suffer from several drawbacks: the use of forming, bending, and stamping processes for tubing results in numerous steps and parts, leading to poor consistency, lower quality, higher rework rates, and lower efficiency. Furthermore, the welding process causes deformation during manufacturing, resulting in inconsistent product quality, affecting overall assembly, higher rework rates, and higher after-sales costs. Welding also increases labor costs and reduces efficiency. Additionally, the aluminum alloy tubing used involves two smelting processes: electrolytic aluminum – melting A00 aluminum ingots – melting aluminum alloy bars – extruding tubing – frame tubing processing, which is detrimental to carbon emission reduction. Therefore, a die-cast electric-assisted bicycle frame is needed to address these issues. Summary of the Invention

[0005] The purpose of this invention is to provide an extrusion-cast electric bicycle frame to solve the problems mentioned in the background art.

[0006] To achieve the above objectives, the present invention provides the following technical solution: an extrusion-cast electric bicycle frame, comprising an upper frame and a lower frame, wherein the upper frame is fixedly mounted on the top of the lower frame, an upper tube is fixedly mounted inside the upper frame, a lower tube is fixedly connected to one end of the upper tube, a middle tube is fixedly connected to the other end of the upper tube, a head tube is fixedly connected to the center of the top of the lower tube, and first nut posts are evenly fixedly connected to both sides of the bottom surface of the upper tube; a right frame is fixedly mounted inside the lower frame, a left frame is fixedly connected to the side of the right frame, a left upright fork is fixedly mounted at the top of the interior of the left frame, and a left horizontal fork is fixedly connected to the interior of the left frame and at the bottom of the left upright fork. A left rear hook is fixedly connected to the inside of the left side of the frame, at one end of the left upright fork. First screw holes are evenly distributed along one edge of the upper surface of the left side of the frame. Second nut posts are evenly fixedly connected along the outer perimeter of the left side of the frame. A left center connector is welded to the bottom of the left side of the frame. A right upright fork is fixedly installed at the top inside of the right side of the frame. A right flat fork is fixedly connected to the inside of the right side of the frame, at one end of the bottom of the left upright fork. A right fork hook is fixedly connected to the inside of the right side of the frame, at one end of the left upright fork. Second screw holes are evenly distributed along one edge of the upper surface of the left side of the frame. Third screw holes are evenly distributed along the outer perimeter of the right side of the frame. A right center connector is welded to the bottom of the right side of the frame.

[0007] Specifically, the upper and lower parts of the frame are made of aluminum alloy.

[0008] Specifically, there are six first nut posts, three first screw holes, seven second nut posts, three second screw holes, and seven third screw holes.

[0009] Specifically, the upper tube is snapped into place by aligning the first screw hole and the second screw hole on the top side of the left and right sides of the frame with the first nut post on the bottom surface.

[0010] Specifically, the left and right sides of the frame are aligned and snapped together by a second nut post and a third screw hole.

[0011] Specifically, the left side of the frame is aligned and snapped together with the right side center connector on the right side of the frame via the left center connector at the bottom of the side.

[0012] Specifically, the first screw hole, the second nut post, and the second screw hole are all internally threaded with fastening bolts.

[0013] Specifically, a battery box is installed inside the lower part of the frame, at the bottom between the left and right sides of the frame.

[0014] Compared with the prior art, the beneficial effects of the present invention are as follows:

[0015] This invention utilizes a one-piece extrusion casting process, enabling each module to be formed in a single, seamless process without welding. The material used is aluminum alloy, further reducing the product's weight while ensuring its strength meets relevant national standards. Electric bicycle frames, tricycle frames, and bicycle frames can all be formed in one piece using this extrusion casting process. Materials include steel, aluminum alloy, aluminum-magnesium alloy, and magnesium alloy.

[0016] This invention applies the extrusion casting process to the manufacture of electric bicycle frames, bicycle frames, and tricycle frames. By employing this process, the frame is modularly manufactured from multiple welded parts, eliminating the need for welding and allowing only bolt fastening to complete the entire frame. Besides extrusion casting, other casting and pressure casting processes are also within the scope of protection for this technical solution. The material used in this technical solution is aluminum alloy; however, the use of steel, aluminum alloy, aluminum-magnesium alloy, and magnesium alloy is also within the scope of protection.

[0017] This invention features a chassis composed of only three modules, resulting in fewer parts, fewer processes, no welding, fewer personnel, higher efficiency, higher labor productivity, better product consistency, significantly improved quality, reduced after-sales workload, reduced unnecessary expenses, lower costs, and also helps reduce carbon emissions. Attached Figure Description

[0018] Figure 1This is a schematic diagram of the main structure of the present invention;

[0019] Figure 2 This is a schematic diagram of the upper part of the frame of the present invention;

[0020] Figure 3 This is a schematic diagram of the lower part of the frame of the present invention;

[0021] Figure 4 This is a schematic diagram of the left side of the vehicle frame of the present invention;

[0022] Figure 5 This is a schematic diagram of the right side of the frame of the present invention.

[0023] In the diagram: 1-Upper part of frame, 2-Left part of frame, 3-Right part of frame, 4-Head tube, 5-Down tube, 6-Top tube, 7-Side tube, 8-First nut post, 9-First screw hole, 10-Left center connector, 11-Left upright fork, 12-Left rear hook, 13-Second nut post, 14-Left horizontal fork, 15-Right upright fork, 16-Right fork hook, 17-Right horizontal fork, 18-Right center connector, 19-Second screw hole, 20-Third screw hole, 21-Battery box, 22-Lower part of frame. Detailed Implementation

[0024] The technical solutions of 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 embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0025] Please see Figure 1-5An embodiment of the present invention provides: an extrusion-cast electric bicycle frame, comprising an upper frame 1 and a lower frame 22. The upper frame 1 is fixedly mounted on the top of the lower frame 22. An upper tube 6 is fixedly mounted inside the upper frame 1. A lower tube 5 is fixedly connected to one end of the upper tube 6, and a middle tube 7 is fixedly connected to the other end of the upper tube 6. A head tube 4 is fixedly connected to the center of the top of the lower tube 5. First nut posts 8 are evenly fixedly connected to both sides of the bottom surface of the upper tube 6. A right frame 3 is fixedly mounted inside the lower frame 22. A left frame 2 is fixedly connected to the side of the right frame 3. A left upright fork 11 is fixedly mounted at the top of the inside of the left frame 2. A left horizontal fork 14 is fixedly connected to the bottom end of the left upright fork 11 inside the left frame 2. A left rear hook 12 is fixedly connected to the bottom end of the left upright fork 11 inside the left frame 2. The surface has a first screw hole 9 evenly distributed on one side edge. The outer edge of the side of the left part 2 of the frame is evenly fixedly connected to a second nut post 13. The bottom of the side of the left part 2 of the frame is welded to a left center connector 10. The top of the inside of the right part 3 of the frame is fixedly installed with a right vertical fork 15. The inside of the right part 3 of the frame and at the bottom end of the left vertical fork 11 is fixedly connected to a right horizontal fork 17. The inside of the right part 3 of the frame and at the end of the left vertical fork 11 is fixedly connected to a right fork hook 16. The upper surface of the left part 2 of the frame has a second screw hole 19 evenly distributed on one side edge. The outer edge of the side of the right part 3 of the frame has a third screw hole 20 evenly distributed on the side edge. The bottom of the side of the right part 3 of the frame is welded to a right center connector 18.

[0026] The upper part 1 and the lower part 22 of the frame are made of aluminum alloy. There are six first nut posts 8, three first screw holes 9, seven second nut posts 13, three second screw holes 19, and seven third screw holes 20, which can enhance the connection stability between the upper part 1, the left part 2 and the right part 3 of the frame.

[0027] The upper tube 6 is aligned and engaged with the first screw hole 9 and the second screw hole 19 on the top side of the left part of the frame 2 and the right part of the frame 3 through the first nut post 8 on the bottom surface, and the left part of the frame 2 and the right part of the frame 3 are aligned and engaged through the second nut post 13 and the third screw hole 20, thereby ensuring the accuracy of the connection and alignment between the upper part of the frame 1, the left part of the frame 2 and the right part of the frame 3.

[0028] The left side 2 of the frame is aligned and snapped together with the right side 3 of the frame via the left center connector 10 at the bottom of the side, which ensures that the left center connector 10 and the right center connector 18 are aligned without deviation.

[0029] The first screw hole 9, the second nut post 13, and the second screw hole 19 are all threaded with fastening bolts, which facilitates the fastening connection between the upper part 1 of the frame, the left part 2 of the frame, and the right part 3 of the frame.

[0030] A battery box 21 is installed inside the lower part 22 of the frame and at the bottom between the left part 2 and the right part 3 of the frame, so as to facilitate the installation of batteries inside the left part 2 and the right part 3 of the frame.

[0031] Working principle: The electric-assisted bicycle frame mainly consists of three modules. The first module is the upper frame 1, which is composed of the head tube 4, lower tube 5, upper tube 6, middle tube 7, and first nut post 8. Furthermore, the head tube 4, lower tube 5, upper tube 6, middle tube 7, and first nut post 8 are located within the upper frame 1. The first module is formed in one piece using a squeeze casting process, completely eliminating welding. The second module is the lower frame 22, which mainly consists of the left frame 2 and the right frame 3. The first screw hole 9, left center joint 10, left upright fork 11, left rear hook 12, second nut post 13, and left horizontal fork 14 inside the left frame 2 are also formed in one piece using the same squeeze casting process, similarly eliminating welding. Similarly, the right upright fork 15, right fork hook 16, right horizontal fork 17, right center joint 18, second screw hole 19, and third screw hole 20 inside the right frame 3 are also formed in one piece using a squeeze casting process, completely eliminating welding. After the upper frame 1, left frame 2, and right frame 3 are extruded and cast, they need to be assembled. First, assemble the left frame 2 and right frame 3, making sure their sides are in contact with each other and aligning the third screw hole 20 and the second nut post 13 on their sides. Then, install the battery box 21 between the sides of the left frame 2 and right frame 3, positioning it at the upper edge of the left center connector 10 and the right center connector 18, and below the first screw hole 9 and the second screw hole 19. Finally, use a fastening bolt to pass through the third screw hole 20. The first nut 8 is threaded to one end of the second nut post 13, thereby securing the left part 2 and the right part 3 of the frame together. This also confines the battery box 21 between the left and right parts of the frame. The lower part 22 of the frame is then assembled. The upper part 1 of the frame is placed at the top center of the lower part 22, aligning the first nut post 8 on the bottom surface of the upper tube 6 with the second screw hole 19 on one side of the top of the left and right parts of the frame. A fastening bolt is then threaded upwards from the bottom of the second screw hole 19 and threaded onto the bottom end of the first nut post 8, thereby securing the battery box 21 between the left and right parts of the frame. The upper part 1 of the frame is fixedly installed on the top of the lower part 22 of the frame, and the upper part 1 and the lower part 22 of the frame are assembled and connected to form a complete electric-assisted bicycle frame. Through the extrusion casting one-piece molding process, each module is one-time extrusion casting molding without welding. The material used is aluminum alloy, which makes the product lighter and the strength meets the requirements of relevant national standards. Electric bicycle frames, tricycle frames and bicycle frames can all be formed in one piece using the extrusion casting one-piece molding process. Materials include steel, aluminum alloy, aluminum-magnesium alloy, magnesium alloy, etc.The process includes casting and pressure casting. By adopting a one-piece extrusion casting molding process, the frame consists of only three modules, resulting in fewer parts, fewer processes, no welding, fewer personnel, higher efficiency, higher labor productivity, better product consistency, significantly improved quality, reduced after-sales workload, reduced unnecessary expenses, lower costs, and also helps reduce carbon emissions.

[0032] Although embodiments of the invention have been shown and described, it will be understood by those skilled in the art that various changes, modifications, substitutions and alterations can be made to these embodiments without departing from the principles and spirit of the invention, the scope of which is defined by the appended claims and their equivalents.

Claims

1. An extrusion-cast electric bicycle frame, comprising an upper frame portion (1) and a lower frame portion (22), characterized in that: The upper part (1) of the frame is fixedly installed on the top of the lower part (22) of the frame. An upper tube (6) is fixedly installed inside the upper part (1). A lower tube (5) is fixedly connected to one end of the upper tube (6). A middle tube (7) is fixedly connected to the other end of the upper tube (6). A head tube (4) is fixedly connected to the center of the top of the lower tube (5). First nut posts (8) are evenly fixedly connected to both sides of the bottom surface of the upper tube (6). The right part (3) of the frame is fixedly installed inside the lower part (22). The left part (2) of the frame is fixedly connected to the side of the right part (3). The left upright fork (11) is fixedly installed at the top of the left part (2). A left flat fork (14) is fixedly connected to the bottom of the left upright fork (11) inside the left part (2). A left flat fork (14) is fixedly connected to the bottom of the left upright fork (11) inside the left part (2). The rear hook (12) has a first screw hole (9) evenly opened on one side edge of the upper surface of the left side (2) of the frame. The second nut post (13) is evenly fixedly connected to the outer edge of the side of the left side (2). The left center connector (10) is welded to the bottom of the side of the left side (2). The right upright fork (15) is fixedly installed at the top inside of the right side (3). The right flat fork (17) is fixedly connected to the bottom end of the left upright fork (11) inside the right side (3). The right fork hook (16) is fixedly connected to the bottom end of the left upright fork (11) inside the right side (3). The second screw hole (19) is evenly opened on one side edge of the upper surface of the left side (2). The third screw hole (20) is evenly opened on the outer edge of the side of the right side (3). The right center connector (18) is welded to the bottom of the side of the right side (3).

2. The electric bicycle frame made by extrusion casting according to claim 1, characterized in that: The upper part (1) and lower part (22) of the frame are made of aluminum alloy.

3. The extrusion-cast electric bicycle frame according to claim 2, characterized in that: The number of first nut posts (8) is six, the number of first screw holes (9) is three, the number of second nut posts (13) is seven, the number of second screw holes (19) is three, and the number of third screw holes (20) is seven.

4. The extrusion-cast electric bicycle frame according to claim 3, characterized in that: The upper tube (6) is aligned and snapped with the first screw hole (9) and the second screw hole (19) on the top side of the left side (2) and the right side (3) of the frame through the first nut post (8) on the bottom surface.

5. The extrusion-cast electric bicycle frame according to claim 4, characterized in that: The left (2) and right (3) parts of the frame are aligned and snapped together by the second nut post (13) and the third screw hole (20).

6. The extrusion-cast electric bicycle frame according to claim 5, characterized in that: The left side (2) of the frame is aligned and snapped together with the right side (3) of the frame via the left center connector (10) at the bottom of the side.

7. The extrusion-cast electric bicycle frame according to claim 6, characterized in that: The first screw hole (9), the second nut post (13), and the second screw hole (19) are all threaded with fastening bolts.

8. The extrusion-cast electric bicycle frame according to claim 7, characterized in that: A battery box (21) is installed inside the lower part (22) of the frame and at the bottom between the left part (2) and the right part (3) of the frame.

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