SCR Doser Electrical Adapter Post-Weld Assembly

Resolve Bottlenecks,
Find Innovative Solutions
Generate Solutions

Solution Overview

Problem

The heat generated during the welding process of an SCR doser's housing can damage the electrical leads within the housing, as they are arranged before the welding occurs, leading to potential electrical connection issues.

Innovation Solution

An electrical adapter with sprung pins and terminals is used, which is inserted through an aperture in the base wall after the injector assembly is enclosed in the housing and welded, ensuring the electrical connections are made after the heat dissipation, with retaining features like grommets and flexible arms to secure the adapter in place, preventing disengagement.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Ease of manufacture

If electrical leads are arranged in the housing before welding, then the housing can be assembled and welded together, but the heat generated by welding damages the electrical leads

Engineering Contradiction:
Improvehousing assemblyVSAvoidelectrical connection
Core Design Contradiction:
Ease of manufactureVSReliability

Solution Approach 1:

The housing is assembled and welded together before the electrical leads are installed. The adapter is inserted through the base wall after welding, and the electrical pins are then connected to the solenoid, reversing the traditional sequence to avoid exposing leads to welding heat

Inventive Principle:
Principle #10Preliminary action

Solution Approach 2:

The electrical connection system is divided into separate components: an adapter inserted through the base wall, electrical pins on the injector assembly, and terminals on the solenoid. This segmentation allows the housing to be welded separately from the electrical connection process

Inventive Principle:
Principle #1Segmentation

2Reliability

If the electrical adapter is inserted through the base wall after welding, then the electrical leads are protected from welding heat, but the adapter must be securely retained in place

Engineering Contradiction:
Improveelectrical connectionVSAvoidadapter retention mechanism
Core Design Contradiction:
ReliabilityVSDevice complexity

Solution Approach 1:

A flexible grommet is used at the aperture in the base wall to retain the adapter. The grommet's flexibility allows the adapter to be inserted while providing frictional retention to hold it in place

Inventive Principle:
Principle #30Flexible shells and thin films

Solution Approach 2:

The grommet acts as an intermediary element between the adapter and the base wall, providing a secure connection without requiring complex mechanical fastening mechanisms

Inventive Principle:
Principle #24Intermediary (Mediator)

Data Source

PatentEP3529470B1SCR doser
Publication Date: 2021.06.30 DELPHI TECH IP LTD
  • EP3529470B1 patent drawingFigure 1
  • EP3529470B1 patent drawingFigure 2~5
  • EP3529470B1 patent drawingFigure 6~7

AI summary

A SCR doser (10) comprising an electrical adapter (64) extending from an inner end electrically connected to the pins (30) of a solenoid to an outer end having electrical terminals (70), the outer end outwardly protruding from an aperture (46, 48) provided in a base wall (32) of the housing of the SCR doser. The adaptor comprises a grommet, which is inserted as a last step in the manufacturing process of the doser and being retained by a flexible parts engaging a groove recess of the base wall.