Railway Switch Frog Point Roller Bracket Design

Resolve Bottlenecks,
Find Innovative Solutions
Generate Solutions

Solution Overview

Problem

Existing railway switch frog systems face challenges with high friction, environmental concerns from lubrication, and space requirements, making them unsuitable for high axle loads and speeds, and difficult to retrofit existing infrastructure.

Innovation Solution

A compact design where a bracket with a central receptacle for the frog engages under the wing rails, using rollers for force transmission and featuring raised sections with pressing edges to ensure the frog point is pressed against the rails, eliminating the need for sliding guides and separate components.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Ease of manufacture

If sliding plates are used to move the frog point between positions, then the structure is simple, but regular lubrication is required increasing workload and environmental concerns arise

Engineering Contradiction:
Improvestructural simplicityVSAvoidmaintenance workload
Core Design Contradiction:
Ease of manufactureVSEase of operation

Solution Approach 1:

The patent replaces the sliding plate mechanical system with a roller-based system. The frog point is mounted on a bracket that is guided on rollers instead of sliding plates, eliminating the need for lubrication while reducing friction. This substitution transforms the mechanical interaction from sliding friction to rolling friction, solving both the maintenance workload and environmental concerns.

Inventive Principle:
Principle #28Mechanics substitution (Replace mechanical system)

2Ease of operation

If frog lifting devices with rollers are used to reduce friction, then friction is reduced without lubrication, but the space required leads to extensive design measures and is not suitable for retrofitting

Engineering Contradiction:
Improvefriction reductionVSAvoiddesign complexity
Core Design Contradiction:
Ease of operationVSDevice complexity

Solution Approach 1:

The patent merges the frog point mounting bracket with the roller guidance system into a single integrated component. The bracket is passed through recesses in the wing rails and is mounted on rollers that are at least partially arranged below the wing rails. This merging eliminates the need for separate lifting devices and extensive design measures, enabling retrofitting of existing switches while maintaining friction reduction benefits.

Inventive Principle:
Principle #5Merging (Combining)

Solution Approach 2:

The patent repositions the rollers from a vertical arrangement (below the frog point) to a lateral arrangement (below the wing rails). This dimensional change allows the bracket to be guided on rollers in a space that does not interfere with the frog point's movement path, reducing the space required and simplifying the overall design for retrofitting applications.

Inventive Principle:
Principle #17Another dimension (Dimensionality change)

3Ease of operation

If the frog point is continuously lifted on rollers, then friction is minimized, but the rollers bear impermissible loads when the switch is in end positions

Engineering Contradiction:
Improvefriction reductionVSAvoidroller load capacity
Core Design Contradiction:
Ease of operationVSStrength

Solution Approach 1:

The patent implements periodic action by transferring the frog point between lifting phases and support phases. During movement between positions, the frog point is lifted on rollers to minimize friction. In end positions, the frog point is lowered onto support surfaces to divert loads from the rollers. This periodic transfer optimizes friction reduction during operation while protecting rollers from excessive static loads.

Inventive Principle:
Principle #19Periodic action

Solution Approach 2:

The patent introduces support surfaces as intermediary elements between the frog point and the rollers. These support surfaces serve as mediators that bear the loads in end positions, preventing impermissible loads on the rollers. The support surfaces are integrated into the bracket structure, allowing seamless transition between roller-supported movement and surface-supported positioning.

Inventive Principle:
Principle #24Intermediary (Mediator)

4Volume of moving object

If a bracket passed through recesses in wing rails is used, then space is reduced, but the structure becomes complex and is not suitable for retrofitting existing switches

Engineering Contradiction:
Improvespace requirementVSAvoidretrofitting capability
Core Design Contradiction:
Volume of moving objectVSAdaptability or versatility

Solution Approach 1:

The patent designs the bracket with universal adaptability to accommodate both new installations and retrofitting applications. The bracket is passed through recesses in the wing rails and is mounted on rollers that can be positioned in available space, creating a multi-functional solution that works for both greenfield and brownfield deployments. This universal design enables the same structure to serve different installation scenarios without modification.

Inventive Principle:
Principle #6Universality (Multi-functionality)

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 optimizes friction conditions, allows for easy retrofitting of existing switches, and ensures reliable positioning of the frog point without additional components, reducing operational effort and environmental impact.

Implementation Method 1

the bracket is mounted on rollers, the rollers each rolling on one of the raceways

Methodology Applied
Scientific EffectRolling friction: Roller

Data Source

PatentEP2414590B1Switch for railway systems
Publication Date: 2014.12.10 BUNTMETALL AMSTETTEN GES
  • EP2414590B1 patent drawingFigure 1~3

AI summary

The invention relates to a switch for railway systems, with a frog (1), the point (1a) of which is movable between a first position bearing against a first wing rail (2) and a second position bearing against a second wing rail (3), with a supporting surface (4) for supporting the frog point (1a), wherein the frog point (1a) rests on a strap (5) which is mounted outside the first and the second wing rail (2, 3) on a respective roller (9a, 9b) in order to lift the frog point (1a) during the movement between the first position and the second position, wherein the rollers (9a, 9b) each roll along a running track (11a, 11b), and at least one running track (11a, 11b) has lowered end sections (12a, 13a; 12b, 13b). A solution which can advantageously be retrofitted is provided by the frog point (1a) engaging under the first and the second wing rail (2, 3) and by the strap (5) having a base (6) which, in the central region thereof, has a receptacle (8) for the frog (1) and which is lowered in relation to laterally adjoining supporting sections (7a, 7b).