Bicycle Twist Grip Shifter with Ball Bearings and Snap Connection

Resolve Bottlenecks,
Find Innovative Solutions
Generate Solutions

Solution Overview

Problem

Existing twist grip shifters for bicycles require additional assembly steps and components, such as separate fixed grip parts, which complicate manufacturing and handling, and may lead to unintentional shifting due to friction issues.

Innovation Solution

An integrated twist grip shifter design where the bearing tube and fixed grip part are securely connected but can be assembled and disassembled individually, featuring a snap connection mechanism and ball bearings to minimize friction, allowing for a secure fit on handlebars without additional assembly steps and offering variants with or without a separate fixed grip.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Reliability

If the bearing tube and fixed grip part are connected in one piece, then safety is improved by preventing unintentional shifting, but manufacturing complexity increases due to requirements for larger injection molding machines

Engineering Contradiction:
ImprovesafetyVSAvoidmanufacturing complexity
Core Design Contradiction:
ReliabilityVSEase of manufacture

Solution Approach 1:

The fixed grip part is separated from the bearing tube, allowing each component to be manufactured independently using standard injection molding machines. The separation enables safer assembly where the fixed grip part can be securely attached to the bearing tube, preventing unintentional shifting while avoiding the need for large-capacity molding equipment.

Inventive Principle:
Principle #1Segmentation

2Ease of manufacture

If the bearing tube and fixed grip part are separated into individual components, then manufacturing is simplified, but assembly complexity increases requiring additional work steps

Engineering Contradiction:
Improvemanufacturing simplicityVSAvoidassembly complexity
Core Design Contradiction:
Ease of manufactureVSDevice complexity

Solution Approach 1:

The fixed grip part and bearing tube are designed with complementary geometric features that enable direct assembly without additional fastening components. The bearing tube includes an outer peripheral surface that fits into a corresponding recess in the fixed grip part, creating a unified structure through simple geometric interlocking rather than requiring separate assembly steps.

Inventive Principle:
Principle #5Merging (Combining)

3Ease of operation

If friction is reduced between the rotary handle and fixed grip part, then operation smoothness is improved, but the grip may slip off the handlebars

Engineering Contradiction:
Improverotation smoothnessVSAvoidgrip security
Core Design Contradiction:
Ease of operationVSReliability

Solution Approach 1:

The bearing tube is designed with differentiated surface characteristics: the outer peripheral surface that interfaces with the fixed grip part has high friction properties to prevent slipping, while the inner peripheral surface that contacts the rotary handle has low friction properties to enable smooth rotation. This local differentiation of surface quality resolves the contradiction between grip security and operational smoothness.

Inventive Principle:
Principle #3Local quality

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 integrated design simplifies manufacturing, reduces friction during operation, and enhances safety by eliminating unintentional shifting, while allowing for easy assembly and disassembly, thus improving user experience and production efficiency.

Implementation Method 1

The arrangement of ball bearings between the bearing tube and the rotary handle in the axial area where the spool for winding the cable to be actuated is located is a measure to minimize friction.

Methodology Applied
Scientific EffectBall bearing: Ball Bearing

Data Source

PatentEP2514662B1Rotary handle with clip-on end piece
Publication Date: 2014.12.03 SRAM
  • EP2514662B1 patent drawingFigure 1
  • EP2514662B1 patent drawingFigure 2
  • EP2514662B1 patent drawingFigure 3

AI summary

The invention relates to a bicycle twist grip shifter that is connected to a fixed grip and mounted as a unit on the handlebar tube. This also securely fixes the fixed grip to the handlebar tube. Furthermore, the individual components are sized for injection molding. The twist grip shifter provides the user with precise operation by eliminating disruptive friction between the twist grip and the bearing tube. This is achieved through the use of ball bearings for the winding spool and the use of a metallic positioning ring in the positioning mechanism.