Belt Type EPS Pulley Structure with Bent Support Frame
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Conventional pulley structures for belt type electric power steering (EPS) gears face challenges in assemblability due to the need for separate press-fitting of flanges, excessive weight from metallic materials, and difficulty in manufacturing integrated flange portions, which limits weight reduction and increases assembly complexity.
Innovation Solution
A pulley structure featuring an insert ring section coupled to a ball nut with a support section, first and second flange sections, and a bent support frame, allowing for internal space and integrated manufacturing using engineering plastic, enabling easier assembly and weight reduction through injection molding.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Strength
If metallic material is used for pulley structure, then strength and durability are improved, but weight increases excessively
Solution Approach 1:
The pulley structure uses composite material construction by integrating engineering plastic for the main body with a sintered metal insert ring for the ball nut coupling section. This combination allows the pulley to achieve the strength and durability of metallic materials while maintaining the weight reduction benefits of plastic materials. The sintered metal insert ring provides high-strength coupling with the ball nut, while the engineering plastic body keeps overall weight low.
2Ease of manufacture
If flange is integrated with nut pulley using sintered material, then manufacturing is simplified, but assemblability deteriorates due to separate press-fitting requirement
Solution Approach 1:
The pulley structure uses composite material construction by integrating engineering plastic for the main body with a sintered metal insert ring for the ball nut coupling section. This combination allows the pulley to achieve the strength and durability of metallic materials while maintaining the weight reduction benefits of plastic materials. The sintered metal insert ring provides high-strength coupling with the ball nut, while the engineering plastic body keeps overall weight low.
Solution Approach 2:
The flange and support frame are integrated into a single unified structure formed by injection molding, eliminating the need for separate assembly operations. This merging of components simplifies both manufacturing and assembly processes, as the integrated structure is produced as one piece and requires no additional fastening or alignment steps during assembly.
3Reliability
If conventional nut pulley structure is used, then belt separation prevention is achieved, but assemblability deteriorates and part count increases
Solution Approach 1:
The flange and support frame are integrated into a single unified structure formed by injection molding, eliminating the need for separate assembly operations. This merging of components simplifies both manufacturing and assembly processes, as the integrated structure is produced as one piece and requires no additional fastening or alignment steps during assembly.
Data Source
AI summary
Provided is a pulley structure of a belt type electric power steering (EPS) gear, and more particularly, a pulley structure of a belt type EPS gear capable of providing good assemblability using an engineering plastic and a specific structure. The pulley structure of the belt type EPS gear includes an insert ring section coupled to a ball nut, a support section configured to support the insert ring section, a first flange section configured to prevent separation of a belt, a pulley having a driving section configured to receive a driving force of the belt, a support frame disposed at one side surface of the driving section and having a bent shape to have an internal space when coupled to the ball nut, and a second flange section disposed at one side surface of the support frame and configured to prevent separation of the belt.