Shift Device Lever Part Stamping and Resin Coating
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Existing shift devices face issues with high manufacturing costs and potential failure under strong forces due to the need for complex machining processes and stiff, solid metal components, which can lead to the operation knob being pulled off from the lever part.
Innovation Solution
A shift device design featuring a lever part with a metal plate having an open cross-sectional shape formed by stamping and coated with a resin material, where the operation knob includes a claw portion and protruding elements that fit into slot or through-hole shaped portions, reducing manufacturing costs and ensuring adequate stiffness and strength.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Reliability
If a strong force acts on the shift knob main body in the pull-off direction, then the elastic flange bends out of the notch and the shift knob main body is pulled off from the shaft, but this results in poor reliability under emergency operation conditions
Solution Approach 1:
The operation knob is divided into a knob outer portion and a knob inner portion that are housed relative to each other. The knob outer portion includes a latch structure with a latch protrusion that engages with a latch groove on the shaft, while the knob inner portion includes a claw portion that hooks the shaft. This segmentation allows the force to be distributed across multiple engagement points, preventing pull-off under emergency conditions.
Solution Approach 2:
The knob inner portion is housed within the knob outer portion, forming a nested structure. The latch protrusion of the knob outer portion fits into the latch groove of the shaft, while the爪 portion of the knob inner portion simultaneously engages with the shaft. This nested arrangement creates redundant engagement mechanisms that work together to prevent pull-off.
2Strength
If a cylindrical component or solid metal component is used for the shift lever to ensure stiffness and strength, then adequate structural integrity is achieved, but the manufacturing cost significantly rises due to required hole machining and groove machining
Solution Approach 1:
The lever part uses a plate-shaped component with a specific cross-sectional shape that provides adequate stiffness and strength through its geometry rather than requiring solid metal construction. This plate structure eliminates the need for complex hole machining and groove machining, significantly reducing manufacturing costs while maintaining structural integrity.
Solution Approach 2:
The cross-sectional shape of the lever part is optimized to provide the necessary stiffness and strength with minimal material. By changing the geometric parameters of the plate structure, the design achieves adequate strength without requiring solid metal construction, thereby reducing manufacturing complexity and cost.
3Reliability
If the knob outer portion is formed in at least two divisions with a latch structure, then the operation knob is ensured to be prevented from getting off the lever part under heavy loads, but the device complexity increases
Solution Approach 1:
The latch structure is integrated into the knob outer portion as an inherent feature rather than a separate component. The latch protrusion is formed as part of the knob outer portion structure, and the engagement with the latch groove on the shaft provides reliable retention without requiring additional complex mechanisms. This merging approach maintains reliability while minimizing device complexity.
Data Source
AI summary
In the present invention, an operation knob is provided with a knob outer section that forms an outer shell, and a knob inner section into which one edge of a lever section is inserted. The knob inner section has a claw section that allows insertion when the lever section is inserted, and once the lever section has been inserted, hooks the lever section towards the inner side of the knob inner section. A groove section is formed in the lever section and extends in a direction perpendicular to the axis direction of the lever section. The knob outer section is made up of two parts, which are an outer casing and a knob cover. The knob cover is provided with protruding sections, which protrude towards the outer casing and fit into the groove section when the lever section is attached to the knob inner section.