Railcar Steering Bogie Plate Spring Support
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
The existing plate spring bogies face issues with steering function deterioration due to inhibited axle box movement in curved sections, and stress concentration leading to reduced strength when attempting to bend the plate springs for horizontal end portions.
Innovation Solution
A railcar steering bogie design featuring a bogie frame with axles, axle boxes, and plate springs where the plate spring end portions are supported by inclined upper surfaces of support seats, and gap bodies allow relative displacement between the axle box and bogie frame, preventing support seat movement and reducing horizontal load components, thus maintaining axle box mobility and plate spring strength.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Reliability
If the upper surface of the spring seat is inclined and the gap body performs elastic deformation, then the axle box can be supported, but the movement of the axle box inward in the car longitudinal direction is inhibited during steering
Solution Approach 1:
The gap body serves as an intermediary element between the spring seat and the axle box suspension. It allows controlled relative movement while maintaining support, enabling the axle box to move inward during steering without directly compromising the support function of the inclined spring seat surface.
2Ease of operation
If both car longitudinal direction end portions of the plate spring are made horizontal, then the movement of the axle box during steering is not inhibited, but stress concentrates on the bent portion of the plate spring
Solution Approach 1:
The invention changes the orientation parameter of the plate spring end portions from horizontal to oblique, extending them obliquely upward along the car longitudinal direction. This parameter change eliminates the need for bending, thereby preventing stress concentration while still allowing free movement of the axle box during steering operations.
3Strength
If the plate spring end portions extend obliquely upward and are supported by inclined surfaces, then the plate spring strength is maintained, but the horizontal component of carbody support load acts outward on the axle box during steering
Solution Approach 1:
The gap body acts as a mediator that decouples the force transmission path. It allows the inclined plate spring end portions to maintain their strength-providing orientation while preventing the horizontal load component from being directly transmitted to the axle box during steering, as the gap body absorbs or isolates this force component.
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 enables smooth passage through curved lines without inhibiting steering axle movement and maintains the strength of the plate spring, preventing wear and enhancing the bogie's steering performance.
Implementation Method 1
gap bodies each provided between an upper surface of the corresponding axle box suspension and a lower surface of the corresponding support seat and configured to allow displacement of the axle box suspension and the support seat in the car longitudinal direction
Implementation Method 2
when vehicle occupancy increases, and a downward load of the carbody increases, the car longitudinal direction middle portion of the plate spring sinks downward
Data Source
AI summary
A railcar steering bogie includes: a bogie frame including a cross beam; pair of axles; axle boxes accommodating bearings; axle box suspensions each including a coupling member coupling the corresponding axle box and bogie frame while allowing relative displacement in a car longitudinal direction; plate spring extending in the car longitudinal direction and including car longitudinal direction end portions extending obliquely upward along the car longitudinal direction and supported above the respective axle boxes and a car longitudinal direction middle portion unfixedly arranged under the cross beam; support seats including respective inclined upper surfaces and supporting the both respective longitudinal direction end portions of the plate spring; and gap bodies each provided between an upper surface of the corresponding axle box suspension and a lower surface of the corresponding support seat and configured to allow displacement of the axle box suspension and the support seat in the car longitudinal direction.