METHOD FOR INTEGRALLY FORMING BICYCLE STEM AND HANDLEBARS

Abstract

A method for integrally forming a bicycle stem and handlebars includes the following steps: material preparation (S1), pre-processing (S2), initial forging (S3), punch forging (S4), and processing and finishing (S5). By making the stem part 101 solid internally and integrally forming it with the two handlebar parts (102), the overall weight and cost are significantly reduced. The integrated stem part (101) and two handlebar parts (102) allow the solid interior of the stem part (101) to withstand greater external forces. The method greatly reduces the assembly steps, thereby speeding up assembly time. The method improves issues of the conventional technology, which requires additional components to combine the stem and handlebars, thereby increasing overall weight. The present invention addresses the issue of the structure being unable to withstand external forces due to excessive hollow parts inside, which could lead to deformation.

Claims

1. A method for integrally forming a bicycle stem and handlebars, comprising the following steps: Material Preparation Step S1: Using casting processing to form a metal billet (100) with an initial stem blank (100A) and a rough handle blank (100B); Pre-processing Step S2: Placing the metal billet (100) into a mold cavity (201) of a mold (200), each of two ends of the mold (200) having a punch opening (202) communicating with a space of the mold cavity (201), the mold cavity (201) including a first section (2011) and two second sections (2012) which are connected to two sides of the first section (2011), the initial stem blank (100A) located corresponding to the first section (2011), the rough handle blank (100B) located corresponding to each of the second sections (2012); Initial Forging Step S3: Processing the mold (200) containing the metal billet (100) so that the metal billet (100) is shaped in the mold cavity (201), after shaping, the metal billet (100) forming a stem part (101) and two handlebar parts (102), the stem part (101) and the two handlebar parts (102) are both solid and integrally formed; Punch Forging Step S4: Using two punch parts (301) of a punching device (300) aligned with the two punch openings (202) of the mold (200), inserting the two punch parts (301) into the mold cavity (201) through the corresponding punch openings (202) to punch the ends of the two handlebar parts (102) so as to form an end hole (103) at the end of each of the two handlebar parts (102), a depth of each end hole (103) being shorter than a length of each handlebar part (102), and Processing and Finishing Step S5: Removing the metal billet (100) with the end holes (103) formed by the punching device (300) from the mold (200), and processing and finishing a surface of the metal billet (100) and an interior of the end holes (103).

2. The method as claimed in claim 1, wherein a processing method of the initial forging step S3 is hot forging or cold forging to change a hardness of the metal billet (100), the stem part (101) of the metal billet (100) is shaped in the first section (2011) to form a reinforced section (1010) and a connecting section (1011), one of two ends of the reinforced section (1010) is connected to the two handlebar parts (102), another one of the two ends is connected to the connecting section (1011), a through hole (1012) is defined from a top end to a bottom end of the connecting section (1011).

3. The method as claimed in claim 2, wherein a cut (1013) is formed in the connecting section (1011), the cut (1013) is defined from an outside of the stem part (101) towards the through hole (1012), the cut (1013) communicates with the through hole (1012).

4. The method as claimed in claim 2, wherein the reinforced section (1010) is triangular in shape, two arc-shaped guide surfaces (1014) are formed between an outer sides of the reinforced section (1010) and each handlebar part (102).

5. The method as claimed in claim 2, wherein a thickness of the reinforced section (1010) from a top surface to a bottom surface is greater than a diameter of each handlebar part (102).

6. The method as claimed in claim 2, wherein a first wire hole (1015) is formed in a wall of the through hole (1012), a second wire hole (1021) is formed in a bottom surface of each end hole (103) of the handlebar parts (102), each second wire hole (1021) passes through the stem part (101) and communicates with the first wire hole (1015).

7. The method as claimed in claim 1, wherein the stem part (101) is pivotally connected to an adapter (500).

8. The method as claimed in claim 1, wherein the stem part (101) is assembled with a front brake (400).

Description

BRIEF DESCRIPTION OF THE DRAWINGS

[0013] FIG. 1 illustrates the steps of the method of the present invention;

[0014] FIG. 2 is a perspective view of the metal billet after casting of the present invention;

[0015] FIG. 3 is a perspective view of the opened mold of the present invention;

[0016] FIG. 4 is a perspective view to show that the metal billet is placed into the mold cavity of the mold of the present invention;

[0017] FIG. 5 shows the operation of heating the mold of the present invention to change the hardness of the metal billet;

[0018] FIG. 6 is a schematic diagram of the action where the two punch parts of the punching device enter through the two punch openings of the mold of the present invention;

[0019] FIG. 7 is a schematic diagram of the action of the two punch parts forging the metal billet of the present invention;

[0020] FIG. 8 is a perspective view of the metal billet shaped according to the mold cavity after forging by the punching device of the present invention;

[0021] FIG. 9 is another perspective view of the forged metal billet of the present invention;

[0022] FIG. 10 is a cross sectional view, taken along line X-X of FIG. 8;

[0023] FIG. 11 is a side view of FIG. 8;

[0024] FIG. 12 is a perspective view of the metal billet of FIG. 8 assembled with the first type of adapter;

[0025] FIG. 13 is a perspective view of the metal billet of FIG. 8 assembled with the second type of adapter;

[0026] FIG. 14 is a perspective view of the metal billet of FIG. 8 assembled with the front brake, and

[0027] FIG. 15 is a schematic diagram of the first wire hole in the metal billet of FIG. 8 communicating with each of the second wire holes.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT

[0028] Referring to FIGS. 1-11, the method for integrally forming a bicycle stem and handlebars, comprising the following steps:

[0029] Material Preparation Step S1: Using casting processing to form a metal billet 100 with an initial stem blank 100A and a rough handle blank 100B. The aforementioned casting process is not limited, but the metal billet 100 needs to undergo trimming, sanding, and other finishing processes after casting.

[0030] Pre-processing Step S2: Placing the metal billet 100 into a mold cavity 201 of a mold 200, each of two ends of the mold 200 having a punch opening 202 communicating with a space of the mold cavity 201, the mold cavity 201 including a first section 2011 and two second sections 2012 which are connected to two sides of the first section 2011 (The shape and size of the mold cavity 201 can vary according to the desired form and size, and are not limited here.), the initial stem blank 100A located corresponding to the first section 2011, the rough handle blank 100B located corresponding to each of the second sections 2012;

[0031] Initial Forging Step S3: Processing the mold 200 containing the metal billet 100 so that the metal billet 100 is shaped in the mold cavity 201 (This invention mainly illustrates hot forging processing. Please refer to the dashed lines in FIG. 5, which represent the heating device. The heating temperature can vary depending on the metal characteristics of the billet 100. In addition to hot forging, cold forging can also be used. The processing methods mentioned here are not limited. This allows the metal billet 100 to change its original hardness so that it can be shaped), after shaping, the metal billet 100 forming a stem part 101 (formed from the initial stem blank 100A) and two handlebar parts 102 (formed from the rough handle blank 100B), the stem part 101 and the two handlebar parts 102 are both solid and integrally formed;

[0032] Punch Forging Step S4: Using two punch parts 301 of a punching device 300 aligned with the two punch openings 202 of the mold 200, inserting the two punch parts 301 into the mold cavity 201 through the corresponding punch openings 202 to punch the ends of the two handlebar parts 102 so as to form an end hole 103 at the end of each of the two handlebar parts 102, a depth of each end hole 103 being shorter than a length of each handlebar part 102, the depth of each end hole 103 being not extended to the position of the stem part 101, and

[0033] Processing and Finishing Step S5: Removing the metal billet 100 with the end holes 103 formed by the punching device 300 from the mold 200, and processing and finishing a surface of the metal billet 100 and an interior of the end holes 103.

[0034] According to the above description of the production steps of the present invention, a complete metal billet 100 is directly formed into a stem part 101 and two handlebar parts 102. This makes the connection between the stem part 101 and the two handlebar parts 102 a solid design, significantly enhancing the impact resistance, shock resistance, and stress endurance of the bicycle frame. Compared to the conventional clamping method, where most of the force is borne solely by the handlebars and often leads to breakage at the clamping points of the vertical pipe clamp and clamp cover, the integrally formed design of the stem part 101 and each handlebar part 102 in this invention effectively strengthens the overall structure's ability to withstand forces. Additionally, since the stem part 101 and the two handlebar parts 102 are integrally formed, the use of excessive components is reduced, thereby decreasing the overall weight and cost, aligning better with the current users' pursuit of lightweight bicycles.

[0035] Please refer to FIGS. 8 to 11, regarding the forming of the stem part 101, during the heating process in the initial forging step S3, the stem part 101 will be shaped mainly according to the cavity shapes of the first section 2011 and the two second sections 2012. In particular, according to the shaping of the first section 2011, the stem part 101 will form a reinforced section 1010 and a connecting section 1011. One end of the reinforced section 1010 is connected to the two handlebar parts 102, while the other end of the reinforced section 1010 is connected to the connecting section 1011. Additionally, a through hole 1012 is provided, which runs from the top end to the bottom end of the connecting section 1011. Furthermore, a cut 1013 is made in the connecting section 1011, starting from the outside of the stem part 101 and extending towards the through hole 1012, thereby connecting the cut 1013 with the through hole 1012.

[0036] Since the reinforced section 1010 is not impacted by the two punch parts 301 during the punch forging step S4, it remains solid internally. The solid design of the reinforced section 1010 enhances the overall external force resistance. The reinforced section 1010 is approximately triangular in shape, two arc-shaped guide surfaces 1014 are formed between the outer sides of the reinforced section 1010 and each handlebar part 102. The thickness of the reinforced section 1010 from the top surface to the bottom surface is greater than the diameter of each handlebar part 102. Utilizing this design, where the thickness of the reinforced section 1010 is greater than the diameter of each handlebar part 102 (as indicated in FIG. 11, where T is the thickness of the reinforced section 1010 and P is the diameter of the handlebar part 102), the reinforced section 1010 can withstand greater external forces and avoid breakage. Additionally, the design of the arc-shaped guide surfaces 1014 mainly provides an aerodynamic effect for the overall structure.

[0037] The present invention is mainly intended to be installed on a bicycle frame. Depending on the different types of frames, the structure of the connecting section 1011 of the stem part 101 will also vary. First, please refer to FIGS. 8 to 11. The cut 1013 design of the connecting section 1011 is narrower. As shown in FIG. 14, this design allows for the installation of a front brake 400. One end of the front brake 400 will pass through the head tube of the bicycle frame and be installed with the connecting section 1011 of this invention. It will pass through the through hole 1012 of the connecting section 1011 and be tightened with a few bolts, causing the cut 1013 to gradually shrink and securely clamp the front brake 400. The number of bolts used in this embodiment is fewer than in conventional bicycle frames, so the overall weight will not be heavier than conventional techniques. Refer to FIG. 12, where the design of the cut 1013 is wider than the cut 1013 in FIGS. 8 to 11. This is mainly to provide a pivotal connection with an adapter 500. With the connecting section 1011 of the stem part 101 pivotally connected to the adapter 500, the user can adjust the tilt angle to suit riding comfort and make adjustments according to different bicycle models. Finally, please see FIG. 13 for another example of using an adapter 500.

[0038] Finally, since a bicycle will have a brake system installed and many electronic accessories, there will be issues with wiring. To keep the appearance neat and avoid exposed wires affecting the ride, the wall of the through hole 1012 is further provided with a first wire hole 1015. Each end hole 103 at the bottom of the handlebar parts 102 is provided with a second wire hole 1021. These second wire holes 1021 pass through the solid part of the stem part 101 and connect to the first wire hole 1015. Users or assemblers can insert the wires of the brake system and electronic accessories through the openings of the end holes 103 in the two handlebar parts 102, then pass them through the second wire holes 1021 to the first wire hole 1015. All wires can be routed out from the first wire hole 1015, making the overall appearance tidier and preventing wire tangling that could affect turning operations during riding. Please refer to FIG. 15 for an illustration.

[0039] While we have shown and described the embodiment in accordance with the present invention, it should be clear to those skilled in the art that further embodiments may be made without departing from the scope of the present invention.