Variable Radius Guide Pin for Disc Brake NVH Reduction
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
The existing disc brake assemblies experience noise, vibration, and harshness due to metal-on-metal contact between guide pins and the interior surfaces of the anchor bracket bores, which is undesirable for efficient braking performance.
Innovation Solution
The guide pins are designed with a circular cross-section having distinct radii and surfaces, including planar surfaces and formed edges, to minimize contact area and reduce friction, thereby reducing noise, vibration, and harshness. These guide pins are concentric with a bushing channel to further enhance the controlled contact.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Ease of manufacture
If guide pins are designed with constant circular cross-section, then manufacturing is simple and efficient, but metal-on-metal contact with bore interior surfaces produces noise, vibration, and harshness
Solution Approach 1:
The guide pin transitions from a constant cross-section to a variable cross-section design where the radius changes along the length of the pin. This local variation in geometry creates specific contact zones that control the interaction with the bore interior surface, reducing harmful metal-on-metal contact while maintaining manufacturing feasibility through standard machining processes
Solution Approach 2:
The invention changes the geometric parameter of the guide pin from a constant radius to a variable radius along its length. This parameter change allows the pin to have different contact characteristics at different positions, reducing noise and vibration by controlling where and how the pin contacts the bore surface
2Ease of operation
If guide pins have clearance between exterior surface and bore interior surface, then guide pins can move freely within bores, but contact between guide pins and bore interior surfaces produces noise, vibration, and harshness
Solution Approach 1:
The variable radius design creates specific localized contact zones along the guide pin length rather than uniform contact. This allows the pin to maintain mobility in certain regions while controlling contact in other regions, reducing harmful interactions while preserving necessary movement capability
Solution Approach 2:
The variable radius profile acts as an intermediary geometry between the guide pin and bore interior surface, mediating the contact interaction to reduce harmful effects while maintaining functional movement
Data Source
AI summary
A guide pin, for a disc brake assembly, comprises a head portion and a stem. The stem extends from the head portion along an axis and has a circular cross section, a first stem portion, and a second stem portion. The first stem portion is adjacent a tip of the stem. The second stem portion is between the first portion and the head portion. The first stem portion has a first radius from the axis and the second stem portion has a second radius from the axis. The second radius is less than the first radius. A surface is on the first and second stem portions. A distance is from a plane to the surface. The plane is parallel to the surface and the axis is in the plane. The distance is less than the second radius.