Electronic Device Casing Position-Limiting Mechanism for Gap Reduction
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Existing electronic device casings suffer from gaps due to weak tension between the battery cover and rear casing, leading to poor waterproof and dustproof performance, inconvenient operation, and abrasion of buckles, which are exacerbated by external impacts.
Innovation Solution
A casing structure with a position-limiting portion extending downward from the second casing and an abutment portion on the first casing, allowing the second casing to rotate and lock securely without interference, ensuring the casings remain closed even under external forces.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Stability of the object's composition
If a locking piece with lock hook and lock groove is used to lock the battery cover and rear casing, then the buckling stability is improved, but the tension between the middle part of the battery cover and rear casing becomes weak, causing the battery cover to bulge and deform
Solution Approach 1:
The locking mechanism is divided into two functional parts: the locking piece at the ends for buckling stability, and the positioning-limiting portion in the middle for tension strength. This segmentation allows each part to specialize in its function without compromising the other.
Solution Approach 2:
The positioning-limiting portion adds a vertical dimension to the locking structure by extending downward from the battery cover to engage with the abutment portion on the rear casing, creating a multi-dimensional locking system that addresses both end-stability and middle-tension.
2Strength
If circle of buckles are arranged on the periphery of the battery cover to increase tensioning force, then the tensioning force between battery cover and rear casing is increased, but the buckles repeatedly rub against the side wall causing abrasion and reduced tensioning force over time
Solution Approach 1:
Instead of having the buckle rub against the side wall (horizontal friction), the positioning-limiting portion engages vertically with the abutment portion through a downward extension, inverting the friction direction to vertical which eliminates repeated rubbing during opening/closing operations.
Solution Approach 2:
The positioning-limiting portion copies the essential locking function of the buckle but implements it through a different geometric configuration (vertical engagement vs. horizontal rubbing), achieving the same tensioning purpose without the wear problem.
3Strength
If buckles are arranged on the battery cover to increase tensioning force, then the tensioning force is increased, but when the hand-held terminal is impacted by external force, the battery cover is easily extruded and deformed, causing the buckle to separate from the clamping groove and form a large gap
Solution Approach 1:
The positioning-limiting portion with its downward extension and abutment surface provides pre-positioning and limiting constraints that prevent excessive deformation under impact, cushioning the effect of external forces before they can cause gap formation.
Solution Approach 2:
The locking system combines two different structural elements (locking piece for buckling and positioning-limiting portion for positioning) to create a composite locking mechanism that provides both tension strength and impact resistance simultaneously.
4Ease of operation
If the position-limiting portion and abutment portion are designed to engage during rotation, then the interference during opening and closing is reduced, but the position-limiting surface must be precisely positioned to move along the correct arc path
Solution Approach 1:
The position-limiting surface is designed as an arc-shaped surface that guides the positioning-limiting portion along a precise circular path during rotation, using geometry rather than complex mechanical guides to achieve accurate positioning with minimal manufacturing tolerance requirements.
Data Source
Figure 1
Figure 2
Figure 3
AI summary
Provided is a casing structure of an electronic device. The casing structure comprises a first casing and a second casing. The second casing is detachably mounted on the first casing, and has a main body portion having a substantially rectangular shape. The main body portion has a first end and a second end arranged oppositely, and the first end is rotatable about and supported by the first casing, such that the first casing and the second casing are in a relatively open state or closed state. The casing structure of an electronic device further comprises: at least one position-limiting portion extending downward from a middle portion of the main body portion and located between the first end and the second end, the position-limiting portion having a position-limiting surface facing upward and sloping toward the first end; and at least one abutment portion located at a position of the first casing corresponding to the position-limiting portion, the abutment portion having a downward-sloping abutment surface that abuts the position-limiting surface. When the second casing is rotated from the open state to the closed state, the position-limiting portion rotates with the first end as an axis, such that the position-limiting surface moves in a substantially arc-shaped path to a position obliquely below the abutment portion so as to contact the abutment surface.