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.

What is claimed is: 
     
         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 ( 100 A) and a rough handle blank ( 100 B);   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 ( 100 A) located corresponding to the first section ( 2011 ), the rough handle blank ( 100 B) 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 ).