Disk Brake Shim Structure for Uniform Pad Pressure
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Conventional disk brake apparatuses experience an imbalance in surface pressure between the brake pad and disk, leading to noise and increased fluid requirement, which degrades vehicle performance and pedal stroke.
Innovation Solution
The disk brake apparatus incorporates an opening in the pad shim, rather than the cover shim, to minimize fluid increase while uniformizing surface pressure, with the opening's inner diameter determined by the center movement distance considering the coefficient of friction between the brake pad and disk.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Object-affected harmful factors
If an opening is formed in the cover shim which comes into contact with the piston member, then the surface pressure is uniformized, but the required amount of fluid increases and piston behavior is disturbed
Solution Approach 1:
The pad shim acts as an intermediary component between the brake pad and the cover shim. By forming the opening in the pad shim rather than the cover shim, the design allows pressure equalization to occur through this intermediate layer, preventing direct disturbance to the piston member's behavior while still achieving uniform surface pressure distribution across the brake pad contact area.
2Object-affected harmful factors
If an opening is formed in the cover shim, then the surface pressure is uniformized, but the piston behavior is disturbed when hydraulic pressure is generated
Solution Approach 1:
The pad shim serves as a mediator that isolates the opening's effect from the piston member. The opening is positioned in the pad shim, which is located between the brake pad and the cover shim, allowing pressure equalization to occur without creating direct communication between the hydraulic pressure source and the opening that would disturb piston behavior.
Solution Approach 2:
The opening is strategically positioned in the pad shim at a location that provides local pressure equalization where needed, while the cover shim maintains its integrity and direct contact with the piston member, preserving reliable piston behavior. The opening's position is optimized to uniformize surface pressure in the brake pad contact area without affecting piston operation.
3Object-affected harmful factors
If the required amount of fluid is increased, then the surface pressure is uniformized, but the pedal stroke is increased and vehicle performance is degraded
Solution Approach 1:
The pad shim with the opening serves as an intermediary structure that achieves pressure uniformization through a different mechanism than increasing fluid volume. The opening allows localized pressure equalization in the brake pad contact area, achieving noise reduction without requiring increased fluid amount, thereby maintaining optimal pedal stroke and vehicle performance.
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
This design minimizes the required fluid amount, improves vehicle performance, and reduces noise during braking by ensuring uniform surface pressure distribution.
Implementation Method 1
a piston member installed in the caliper body, and moved by hydraulic pressure
Implementation Method 2
the brake pad is pressed against the disk by the piston which is advanced or retreated, thereby generating a friction force
Data Source
AI summary
A disk brake apparatus may include a caliper body installed on the outer circumference of a disk; a piston member installed in the caliper body, and moved by hydraulic pressure; a brake pad pressed toward the disk by the piston member; and a shim plate installed between the piston member and the brake pad, formed in a plate shape, and abutting on a piston contact part installed on a surface of the piston member, facing the brake pad, the shim plate may include a cover shim brought into contact with the piston contact part; and a pad shim stacked on a surface of the cover shim, facing the brake pad, and including an opening formed through a region which overlaps at least a part of the piston contact part.