Power Module Overmolding Retention via Attachment Tenons

Resolve Bottlenecks,
Find Innovative SolutionsGenerate Solutions

Solution Overview

Problem

Power modules with overmolding in motor vehicle environments face detachment due to mechanical vibrations, which compromises their reliability.

Innovation Solution

Incorporating attachment tenons on the electrical connection parts that project from the main plates, allowing the overmolding to cover these tenons, thereby increasing the contact surface area and enhancing retention.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Reliability

If the power module is subjected to mechanical vibrations in motor vehicle environments, then the overmolding becomes detached over time, but the power module needs to maintain reliable electrical connections and structural integrity

Engineering Contradiction:

Improveovermolding retentionVSAvoidmechanical vibrations

Core Design Contradiction:

ReliabilityVSObject-affected harmful factors

Solution Approach 1:

The patent introduces attachment tenons that extend in a projection direction perpendicular to the main plate plane, adding a vertical dimension to the attachment interface. This dimensional extension increases the contact surface area between the overmolding and connection parts, providing enhanced mechanical interlocking that resists vibration-induced detachment forces.

Inventive Principle:

Principle #17Another dimension (Dimensionality change)

Solution Approach 2:

The electrical connection parts are divided into functional segments: the main plate for electrical connections and the attachment tenon for mechanical retention. This segmentation allows the overmolding to engage with dedicated retention features (tenons) separate from the electrical connector elements, improving overall retention without interfering with electrical functionality.

Inventive Principle:

Principle #1Segmentation

2Reliability

If attachment tenons are added to increase contact surface area, then overmolding retention is improved, but the device complexity increases

Engineering Contradiction:

Improveovermolding retentionVSAvoidconnection part structure

Core Design Contradiction:

ReliabilityVSDevice complexity

Solution Approach 1:

The attachment tenon is integrated with the main plate as a single piece, formed by continuation of material. This merging of the retention feature with the electrical connection part eliminates the need for separate retention components, reducing assembly steps and overall device complexity while still providing enhanced overmolding retention.

Inventive Principle:

Principle #5Merging (Combining)

Solution Approach 2:

The main plate serves dual functions: establishing electrical connections through its conductive properties and providing mechanical retention through the integrated attachment tenon. This multi-functionality reduces the total number of components needed, as the same structural element (main plate) performs both electrical and mechanical retention roles.

Inventive Principle:

Principle #6Universality (Multi-functionality)

Data Source

PatentUS20230128774A1Power module with overmoulding, devices comprising such a power module and method for manufacturing a power module with overmoulding

Publication Date: 2023.04.27 VALEO EQUIP ELECTRIC MOTEUR

AI summary

A power module having electrical connection parts, preferably made of metal, each having a main plate, the main plates extending in one and the same main plane so as to be substantially coplanar. At least one of the electrical connection parts includes at least one electrical connector projecting from its main plate. At least one transistor is electrically connected between two upper faces of respectively two of the main plates, and an electrically insulating overmolding, for example made of resin, covers each transistor and at least one portion of the upper faces of the main plates.