Electric Junction Box Drain Part Design

Solution Overview

Problem

Existing electric junction boxes for motor vehicles face issues with water drainage, leading to potential short circuits or corrosion due to water accumulation, and existing solutions complicate the structure and increase size.

Innovation Solution

An electric junction box design featuring a drain part on the inner case surface that directs water downward and outward, using a combination of ribs and grooves to prevent scattering and ensure effective drainage, with a simple structure that maintains a compact size.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Reliability

If a duct is provided in the case to drain water, then water drainage function is improved, but the structure becomes complicated and size increases

Engineering Contradiction:

Improvewater drainage functionVSAvoidstructure complexity

Core Design Contradiction:

ReliabilityVSDevice complexity

Solution Approach 1:

The drainage function is extracted from a separate duct structure and integrated directly into the connector block body. The groove and drain outlet are formed as integral parts of the connector block, eliminating the need for a separate duct component in the case. This simplifies the overall structure while maintaining effective water drainage capability.

Inventive Principle:

Principle #2Taking out (Extraction)

Solution Approach 2:

The drainage structure (groove and drain outlet) is merged with the connector block body as an integrated unit. Instead of being a separate component, the drainage features are formed directly in the connector block, combining the connector function with the drainage function in a single component, thereby reducing structural complexity.

Inventive Principle:

Principle #5Merging (Combining)

2Reliability

If a duct is provided in the case to drain water, then water drainage function is improved, but the size of the electric junction box becomes large

Engineering Contradiction:

Improvewater drainage functionVSAvoidsize of electric junction box

Core Design Contradiction:

ReliabilityVSVolume of moving object

Solution Approach 1:

The drainage function is extracted from a separate duct structure and integrated directly into the connector block body. The groove and drain outlet are formed as integral parts of the connector block, eliminating the need for a separate duct component in the case. This simplifies the overall structure while maintaining effective water drainage capability.

Inventive Principle:

Principle #2Taking out (Extraction)

Solution Approach 2:

The drainage structure (groove and drain outlet) is merged with the connector block body as an integrated unit. Instead of being a separate component, the drainage features are formed directly in the connector block, combining the connector function with the drainage function in a single component, thereby reducing structural complexity.

Inventive Principle:

Principle #5Merging (Combining)

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 design securely drains water without scattering it onto the wiring board, preventing damage from water entry and maintaining a compact, simplified structure.

Implementation Method 1

Water which enters into the case through the hole reaches the bottom surface of the connector block, is absorbed in the groove, and is drained to the outside of the connector block from the drain outlet.

Methodology Applied

Scientific EffectCapillary action: Capillary Action

Implementation Method 2

a drain part provided on an inner surface of the case so that water, which enters into the case from the hole and is drained from the connector block, moves downward along the inner surface of the case and is drained outside the case

Methodology Applied

Scientific EffectGravity: Gravitation

Data Source

PatentUS7883342B2Electric junction box

Publication Date: 2011.02.08 YAZAKI CORP

AI summary

An electric junction box which includes: a wiring board; a connector block having a body part and terminals, the terminal penetrating through a bottom wall of the body part and one end part of the terminal being electrically connected to the wiring board; a case which is arranged above the bottom wall of the body part, has holes each of which allows an opposite end part of the terminal to pass therethrough so as to expose the terminal, and receives the wiring board and the connector block therein; and a drain part provided on an inner surface of the case so that water, which enters into the case from the hole and is drained from the connector block, moves downward along the inner surface of the case and is drained outside the case.