Caliper Brake Seal Groove Geometry for Drag-Free Piston Rollback
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Conventional caliper brakes experience a drag phenomenon due to premature piston advancement during high pressure braking, leading to inefficient rollback and increased braking fluid requirements, which affects fuel efficiency and pedal feel.
Innovation Solution
The caliper brake design includes a seal groove with a protrusion on the front braking surface and inclined surfaces, allowing for enhanced elastic deformation and improved rollback performance without increasing the required braking fluid volume, thus preventing premature deformation and maintaining efficient assembly.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Reliability
If the elastic deformation movable range of the seal member is increased by expanding the inclined surface of the seal groove, then the rollback performance is improved, but the required amount of braking fluid increases leading to increased invalid stroke and reduced pedal feel
Solution Approach 1:
The seal groove is designed with different width characteristics at different locations: the seating surface side and piston side have greater widths than the intermediate portion. This local variation in geometry allows the seal member to achieve sufficient elastic deformation for complete rollback while limiting the overall volume change that would require additional braking fluid.
2Reliability
If the elastic deformation movable range of the seal member is increased, then the rollback performance is improved, but the invalid stroke increases and pedal feel is reduced
Solution Approach 1:
By creating a seal groove with non-uniform width (wider at seating surface and piston sides, narrower at intermediate portion), the design enables the seal member to deform sufficiently for complete piston rollback while minimizing the total volume change. This prevents excessive invalid stroke and maintains responsive pedal feel during braking operation.
3Reliability
If the seal member deforms prematurely during low pressure braking, then the piston returns to original position, but the amount of braking fluid required increases
Solution Approach 1:
The seal groove geometry is specifically designed with width variations that control the elastic deformation characteristics of the seal member. The wider sections at the seating surface and piston sides provide necessary deformation space for complete rollback, while the narrower intermediate portion limits excessive deformation that would consume additional braking fluid during low pressure braking.
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 design ensures full rollback performance during high pressure braking, reduces drag, and improves fuel efficiency by minimizing the amount of braking fluid needed, while maintaining pedal feel and assembly efficiency.
Implementation Method 1
the seal member is deformed and restored by elasticity thereof, and the piston, which has moved forward, retracts again to return its original position by the elasticity of the seal member
Data Source
AI summary
Disclosed herein a caliper brake includes a carrier in which a pair of pad plates are installed to move forward and backward toward a disk; a caliper housing slidably installed on the carrier and provided with a cylinder; a piston installed in the cylinder and configured to move forward and backward toward the pair of pad plates by a braking hydraulic pressure; a seal member in close contact with an outer surface of the piston and an inner surface of the cylinder, the seal member having a ring-shaped; and a seal groove formed to be recessed in the inner surface of the cylinder to accommodate the seal member, the seal groove including a front braking surface facing a front surface of the seal member; wherein the front braking surface includes a protrusion protruding toward the seal member.