Spring-Loaded Gate Retraction Device for Rail-Road Crossing
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Current spring-loaded gate return devices are limited to 45-degree rotation, often fail to return the gate arm due to spring popping out of a detent, and require a shear pin, which is prone to failure, especially when rotating from angles above horizontal.
Innovation Solution
A spring-loaded gate retraction device utilizing a two-ended pin and spring-catching washers to enable bi-directional 60-degree rotation, eliminating the need for a shear pin by using a frame with angled end plates and a deeper detent in the ramp to maintain spring compression and prevent unintended operation.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Reliability
If a traditional spring-loaded gate return device is used with a detent and notch mechanism, then the gate arm can be returned to home position, but the spring pops out of the detent causing device failure
Solution Approach 1:
The patent transitions from a two-dimensional notch-based spring retention system to a three-dimensional ramp-based system with angled end plates. The ramp structure provides a tapered surface that guides the spring into a deeper, more secure detent position, preventing spring ejection while accommodating larger rotation angles up to 60 degrees.
Solution Approach 2:
The patent modifies the geometric parameters of the retention mechanism by increasing the detent depth and introducing angled end plates with specific ramp angles. These parameter changes enhance the spring's engagement with the detent, ensuring reliable retention during bi-directional rotation up to 60 degrees without spring popping out.
2Adaptability or versatility
If the gate return device is limited to 45 degree rotation, then the structure remains simple, but the device fails to return gate arm from angles above horizontal
Solution Approach 1:
The patent enables dynamic rotation capability by designing a pivot assembly that can accommodate bi-directional rotation up to 60 degrees. The main pivot assembly with angled end plates and ramp structure allows the gate arm to rotate through a larger angular range while maintaining structural integrity and proper spring engagement throughout the motion range.
Solution Approach 2:
The patent adds angular dimensionality to the rotation capability by introducing angled end plates and a ramp-based detent system. This dimensional enhancement allows the device to handle rotation angles exceeding the traditional 45-degree limit, providing versatility for gate arms positioned at various angles above and below horizontal while maintaining a relatively compact structure.
3Reliability
If a shear pin is used in the assembly, then the gate arm can be returned from impact positions, but the shear pin is prone to failure requiring replacement by railroad worker
Solution Approach 1:
The patent removes the shear pin component from the assembly by replacing it with a ramp-based detent system and angled end plates. This extraction eliminates the weak point that required periodic replacement, as the new design uses the ramp structure and spring mechanism to safely manage impact forces without relying on a sacrificial shear pin that needs maintenance intervention.
Solution Approach 2:
The patent implements a self-maintaining system where the spring-loaded mechanism with ramp and detent automatically manages impact events. The system self-regulates by allowing controlled deformation and energy absorption through the spring and ramp structure, eliminating the need for external intervention to replace shear pins after impact events, thus reducing maintenance requirements.
4Reliability
If the device uses a two-ended pin with spring-catching washers instead of a notch, then the spring is prevented from moving, but the device requires more complex assembly
Solution Approach 1:
The patent introduces spring-catching washers as intermediary components between the two-ended pin and the spring. These washers serve as mediators that capture and retain the spring in the correct position, preventing spring movement while distributing loads. The washers simplify the overall assembly by providing a straightforward capture mechanism that integrates easily with the pin and end plate structure.
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 device effectively returns the gate arm to its home position from 60 degrees in both directions and up to 60 degrees from horizontal without spring failure, eliminating the need for shear pins and enhancing maintenance by reducing the risk of shear bolt failure and high wind-induced operation.
Implementation Method 1
a first spring having a first end and a second end. The first spring is disposed horizontally lengthwise on the first side of the main pivot assembly and coupled to the frame on the first end of the first spring and detachably coupled to the first length of the pin of the main pivot assembly on the second end of the first spring
Data Source
AI summary
A gate retraction device is provided to return a crossing gate arm to a home position. The gate retraction device comprises a frame to hold a gate pivot pin that is configured to provide a bi-directional rotation of the crossing gate arm. The gate retraction device further comprises a main pivot assembly that receives the gate pivot pin on one end so as to enable rotation of the main pivot assembly in a horizontal plane. The main pivot assembly comprises a first side and a second side opposite of the first side and wherein the main pivot assembly further comprises a spring pin extending on the first side and the second side of the main pivot assembly. The gate retraction device further comprises a spring-loaded assembly trapped against the spring pin of the main pivot assembly as the main pivot assembly rotates.