Interconnected-Slider Polymer Mold for One-Piece Bicycle Frames
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Existing bicycle frame manufacturing methods face challenges in achieving lightweight, precise, and repeatable structures while controlling material thickness and reducing production costs and time.
Innovation Solution
A mold design with interconnected sliders that form a solid structure to resist injection forces, ensuring consistent material thickness and repeatability, using a polymer material injection process to create a monobloc frame with controlled hollow parts.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Weight of moving object
If carbon composite layup with vacuum curing is used, then lightweight frames are obtained, but production costs become very expensive due to high labor costs
Solution Approach 1:
The patent replaces manual mechanical layup operations with an automated injection molding process. The injection machine automatically injects thermoplastic material into the mold, eliminating the need for manual cutting, draping, and vacuum curing operations, thereby reducing labor costs while maintaining frame lightness through optimized material distribution
Solution Approach 2:
The patent changes the material state from thermosetting composite (requiring curing) to thermoplastic material (enabling injection molding). This parameter change allows automated processing and reduces production complexity, making lightweight frame manufacturing more cost-effective
2Shape
If carbon composite layup with bladder inflation is used, then hollow bodies with complex shapes are produced, but thickness variations occur leading to poor precision and repeatability
Solution Approach 1:
The patent replaces the mechanical bladder inflation system with a controlled injection molding system. The injection process precisely controls material flow and pressure, ensuring uniform wall thickness throughout the hollow structures while maintaining complex geometries, thereby improving both precision and repeatability
Solution Approach 2:
The injection molding process incorporates feedback control through pressure sensors and flow monitoring that adjust injection parameters in real-time, ensuring consistent material distribution and uniform thickness across all hollow body sections, eliminating the thickness variations inherent in bladder inflation methods
3Ease of manufacture
If frame is made by welding or gluing tubes, then manufacturing is simple and inexpensive, but frame quality is only average suitable for entry-level bikes
Solution Approach 1:
The patent merges multiple manufacturing operations (mold making, material shaping, hollow body formation, and assembly) into a single injection molding process. The mold itself is designed with integrated features that form all frame components in one piece, eliminating the need for separate welding or gluing operations while producing high-quality, consistent results
Solution Approach 2:
The patent incorporates preliminary action by pre-designing the mold with precise geometric features and hollow body formations that define the final frame shape. This preliminary mold design ensures that each frame produced has consistent, high-quality dimensions and geometry, superior to post-assembly welding or gluing methods
4Adaptability or versatility
If half-frame parts are manufactured and assembled, then production flexibility is achieved, but connection robustness and dimensional stability deteriorate over time
Solution Approach 1:
The patent merges separate half-frame production and assembly operations into a single monobloc injection molding process. The mold is designed to form the complete frame as one integrated piece, eliminating all connections and joints, thereby ensuring permanent structural integrity and dimensional stability while maintaining production flexibility through mold design variations
Applied Scientific Principles
This section explains which scientific principles are used to turn an abstract innovation direction into a practical engineering solution.
Function Achieved in This Case
The mold achieves lightweight, structurally sound frames with precise thickness and dimensional consistency, reducing production costs and time through automation and optimized material usage.
Implementation Method 1
by injecting a polymer material into said mold
Data Source
Figure 1~2
Figure 3~4
Figure 5~6
AI summary
The present invention relates to a mold (1) for manufacturing a one-piece frame (32) of a bicycle, tricycle, quadricycle, or motorcycle by injection of a polymer material, the mold (1) comprising a fixed part (2) and a movable part (3) adapted to move towards or away from the fixed part to close or open the mold respectively, which together define a molding cavity (8) of the frame when the mold is closed, the mold (1) being characterized in that: it comprises at least three of the following cavities and corresponding slides: - a first cavity (11) having a fork pivot profile (33) of the frame, and a first slide (15) adapted to be inserted into the first cavity (11), - a second cavity (12) which communicates with the first cavity (11), having a diagonal tube profile (34) of the frame, and a second slide (16) adapted to be inserted into the second cavity (12),- a third impression (13) which communicates with the second impression (12), having a base profile (35) and seat stays (36), and a third slider (17) adapted to be inserted into the third impression (13), - a fourth impression (14) which communicates with the third impression (13), having a seat post profile (37), and a fourth slider (18) adapted to be inserted into the fourth impression (14).