Stator Core Module Assembly Using Nested Fasteners

Solution Overview

Problem

Existing stator core module assembly methods require precise reassembly to maintain continuity and prevent gaps or voids, which becomes impractical when modules are lost due to handling issues, necessitating a return to time-consuming hand-stacking techniques.

Innovation Solution

A stator core module design featuring a main body with core rings, through-holes, counter-bores, and fastener assemblies composed of epoxy glass rods and Belleville washers, allowing for alignment and coupling of modules without vacuum pressure impregnation bonding, enabling efficient assembly and accommodation of surface variations.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Reliability

If vacuum pressure impregnation bonding is used to form stator core modules, then the core rings are securely bonded together, but the assembly process becomes time-consuming and complex when modules need to be reassembled or replaced

Engineering Contradiction:

Improvebonding strengthVSAvoidassembly time

Core Design Contradiction:

ReliabilityVSLoss of time

Solution Approach 1:

The stator core is divided into multiple discrete modules that can be independently assembled and replaced. Each module contains core rings secured by fastener assemblies with threaded rods, nuts, and washers, allowing individual module replacement without affecting other modules. This segmentation enables rapid field replacement while maintaining overall stator integrity.

Inventive Principle:

Principle #1Segmentation

Solution Approach 2:

The patent replaces the chemical bonding process (vacuum pressure impregnation) with a mechanical fastening system. Threaded epoxy glass rods, nuts, and Belleville washers provide secure mechanical attachment of core rings, eliminating the need for time-consuming adhesive curing processes while maintaining structural integrity and enabling easy disassembly and replacement.

Inventive Principle:

Principle #28Mechanics substitution (Replace mechanical system)

2Manufacturing precision

If precise reassembly is required to maintain continuity between modules, then gaps and voids are prevented, but the complexity of the assembly process increases significantly

Engineering Contradiction:

Improvealignment precisionVSAvoidassembly complexity

Core Design Contradiction:

Manufacturing precisionVSDevice complexity

Solution Approach 1:

The fastener assemblies are designed to nest within counter-bores in adjacent modules. The threaded rods extend through aligned holes in multiple core rings and are secured with nuts that nest within counter-bores, providing self-aligning features that simplify the assembly process while ensuring precise positioning and continuity between modules.

Inventive Principle:

Principle #7Nested doll (Nesting)

Solution Approach 2:

Counter-bores are pre-formed in the core rings during manufacturing, creating ready-received cavities for the fastener assemblies. This preliminary preparation of alignment features eliminates the need for field alignment operations and ensures consistent positioning when modules are assembled or replaced.

Inventive Principle:

Principle #10Preliminary action

3Adaptability or versatility

If traditional hand-stacking techniques are used to replace lost modules, then flexibility is maintained, but the replacement process becomes impractically time-consuming

Engineering Contradiction:

Improvereplacement flexibilityVSAvoidreplacement speed

Core Design Contradiction:

Adaptability or versatilityVSProductivity

Solution Approach 1:

The stator core is divided into multiple discrete modules that can be independently assembled and replaced. Each module contains core rings secured by fastener assemblies with threaded rods, nuts, and washers, allowing individual module replacement without affecting other modules. This segmentation enables rapid field replacement while maintaining overall stator integrity.

Inventive Principle:

Principle #1Segmentation

Solution Approach 2:

The patent replaces the chemical bonding process (vacuum pressure impregnation) with a mechanical fastening system. Threaded epoxy glass rods, nuts, and Belleville washers provide secure mechanical attachment of core rings, eliminating the need for time-consuming adhesive curing processes while maintaining structural integrity and enabling easy disassembly and replacement.

Inventive Principle:

Principle #28Mechanics substitution (Replace mechanical system)

Data Source

PatentUS9455611B2Process for assembling a stator core assembly

Publication Date: 2016.09.27 SIEMENS ENERGY INC

AI summary

The present invention comprises a process for assembling a stator core assembly to replace existing stator cores in electric power generators. First and second stator core modules are positioned adjacent to one another such that one end of a fastener assembly in the second stator core module is nested in a counter-bore of the first stator core module and one end of a fastener assembly in the first stator core is nested in a counter-bore of the second stator core module.