Railcar Brake Control Device Adhesion Management
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
When switching from an electric brake to an air brake in railcars, there is a risk of excessive braking force leading to increased slip and wheel lock, especially when the friction coefficient between the wheel and rail is low, resulting in longer braking distances.
Innovation Solution
A brake control device that includes a brake switching portion to transition from electric to mechanical braking when the wheelset speed drops below a threshold, and an adhesion control portion to ensure the wheel adheres to the rail during this switch, preventing excessive slip and lock.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Reliability
If switching from electric brake to air brake is performed when wheelset speed decreases to low speed range, then braking force continuity is maintained, but excessive braking force causes slip increase and wheel lock
Solution Approach 1:
The air brake is activated in advance before the electric brake is completely deactivated during the switching process. This preliminary action ensures braking force continuity while the adhesion control portion monitors and adjusts the braking force to prevent excessive slip and wheel lock, resolving the contradiction between maintaining continuity and preventing harmful effects.
2Reliability
If both electric brake and air brake operate simultaneously during switching, then braking force interruption is prevented, but total braking force becomes excessive
Solution Approach 1:
The adhesion control portion continuously monitors the adhesion state between wheel and rail during the brake switching process. When it detects that the total braking force becomes excessive, it provides feedback to adjust and reduce the braking force, thereby preventing slip increase and wheel lock while maintaining braking force continuity.
3Device complexity
If brake switching is performed without adhesion control, then system complexity is reduced, but slip increases and braking distance lengthens
Solution Approach 1:
The adhesion control portion automatically monitors and adjusts the braking force during switch 切换 based on real-time adhesion conditions, enabling the system to self-regulate without requiring complex external intervention. This self-service approach prevents excessive slip and shortens braking distance while maintaining reasonable system complexity.
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 solution prevents slip increase and wheel lock, thereby shortening the braking distance by ensuring proper adhesion during the switching process.
Implementation Method 1
an electric brake device configured to cause an electric motor that is a driving power source to serve as a power generator to brake a wheel
Implementation Method 2
an air brake device configured to cause a brake shoe or the like to drive by air pressure to brake the wheel by friction
Data Source
AI summary
A brake control device of a railcar includes: a brake switching portion configured to perform switching from an operation of an electric brake device to an operation of a mechanical brake device when a switching monitoring speed obtained from a wheelset speed becomes less than a switching threshold; and an adhesion control portion configured to, when the brake switching portion performs the switching, control at least one of the electric brake device and the brake switching portion to cause a wheel to adhere to a rail.