Board Unit Tool-Insertion Recessed Portion for Cover Release
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Existing board unit designs face difficulties in easily releasing the engagement between a case and a cover, particularly due to the obstruction of tool insertion caused by stepped surfaces, making it hard to detach the cover using a tool.
Innovation Solution
The design incorporates engagement protruding and recessed portions on the case and cover, along with a tool-insertion recessed portion at the boundary between the stepped surface and the cover's lower end surface, allowing for easy release of the engagement state using a tool, while maintaining a flush surface for compactness and protecting against water ingress.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Reliability
If a stepped surface is formed in the frame of the case and the lower end surface of the side wall portion of the cover abuts against it, then the engagement between case and cover is ensured, but the tip of a tool cannot be inserted between the frame and the side wall portion, making it difficult to release the engagement
Solution Approach 1:
The side wall of the cover is segmented into two functional regions: an upper engagement portion that abuts against the stepped surface for reliable engagement, and a lower tool-accessible portion that provides access to the tool-insertion recessed portion. This segmentation allows the same side wall to fulfill both engagement reliability and ease of release operation requirements.
Solution Approach 2:
A tool-insertion recessed portion is introduced as an intermediary element that mediates between the tool and the engagement protruding/recessed portions. This recessed portion allows the tool tip to access and manipulate the engagement mechanism without requiring direct access between the tool and the main engagement interface, thus resolving the contradiction between engagement reliability and ease of release.
2Stability of the object's composition
If the lower end surface of the side wall portion abuts against the stepped surface over its entire length, then stable engagement is achieved, but the boundary between the stepped surface and the lower end surface obstructs tool insertion
Solution Approach 1:
The side wall structure is divided into distinct functional segments: an upper engagement region that maintains stable contact with the stepped surface, and a lower access region that incorporates the tool-insertion recessed portion. This segmentation enables the structure to achieve both engagement stability and tool accessibility without increasing overall complexity.
Solution Approach 2:
Different regions of the side wall are given different local qualities: the upper portion maintains a flat engagement surface for stable abutment against the stepped surface, while the lower portion incorporates a recessed portion with specific geometric features that facilitate tool insertion. This local differentiation resolves the contradiction between stability and accessibility.
3Ease of operation
If engagement protruding and recessed portions are provided for easy tool-based release, then ease of operation is improved, but the overall size of the board unit may increase
Solution Approach 1:
The engagement protruding portion and recessed portion are merged into the existing side wall structure of the cover, rather than being added as separate external components. The tool-insertion recessed portion is integrated into the lower end of the side wall, combining multiple functions (engagement, tool access, and size reduction) into a unified structure that minimizes the overall board unit volume.
Solution Approach 2:
The tool-insertion recessed portion is nested within the lower end region of the side wall, utilizing the existing structural space rather than adding external protrusions. This nesting approach allows the engagement release mechanism to be compactly integrated into the cover structure, preventing an increase in the overall board unit size while maintaining ease of operation.
Data Source
AI summary
A board unit includes a circuit board, a case for accommodating the circuit board and a bus bar electrically connected to the circuit board. A power supply terminal connects a lead-out portion of the bus bar and a connection terminal of an electrical wire. A cover covers the power supply terminal, and has a side wall overlapping the outer side of a side surface of a peripheral wall portion of the case. A stepped surface against which a lower end surface of the side wall of the cover abuts is formed in the side surface of the peripheral wall portion of the case. An engagement protruding portion is provided in the peripheral wall portion and the side wall of the cover. An engagement recessed portion engages the engagement protruding portion. A tool-insertion recessed portion releases the engagement protruding portion from the engagement recessed portion.