Solar Cell Positioning in Electronic Timepiece Movement
Solution Overview
Problem
The integration of a solar cell in electronic timepieces poses challenges in reducing the size of the movement while maintaining a calendar function, as the solar connection spring interferes with the trigger piece and yoke, preventing the use of a calendar wheel.
Innovation Solution
An electronic timepiece design featuring a solar cell with a solar cell holding member, a light-transmissive character plate, a ground plate, and a ring-shaped calendar wheel, where the solar cell is positioned on the inside of the calendar wheel, allowing the conduction spring to be placed within the calendar wheel, thus reducing movement size and enabling calendar functionality.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Ease of manufacture
If the solar connection spring is arranged on the outer periphery of the movement, then the solar cell can be connected to charge the secondary battery, but the movement size increases and calendar function cannot be implemented
Solution Approach 1:
The patent transitions the solar connection spring arrangement from a two-dimensional outer periphery layout to a three-dimensional configuration where the spring is positioned within the depth of the movement, specifically in the space between the calendar wheel and the solar cell. This dimensional change allows the spring to occupy unused vertical space rather than expanding the horizontal footprint, thereby reducing movement size while maintaining solar charging functionality.
Solution Approach 2:
The solar connection spring is nested within the existing movement structure, specifically positioned in the gap between the calendar wheel and solar cell. This nesting approach allows the spring to be accommodated within the existing component boundaries without requiring additional external space, effectively utilizing otherwise wasted space within the movement assembly.
2Stability of the object's composition
If the solar connection spring is arranged near the trigger piece and yoke, then the movement structure can be maintained, but the calendar wheel arrangement is interfered with and calendar function cannot be achieved
Solution Approach 1:
The solar connection spring is extracted from its traditional position near the trigger piece and yoke, and relocated to the space between the calendar wheel and solar cell. This extraction removes the interference between the spring and calendar wheel components, allowing the calendar function to be implemented without structural conflicts while maintaining the overall movement integrity.
Solution Approach 2:
The spring is repositioned from a horizontal arrangement near the trigger piece to a vertical arrangement within the depth of the movement between the calendar wheel and solar cell. This dimensional relocation eliminates spatial interference with the calendar wheel while preserving the movement's structural stability.
3Volume of moving object
If the movement size is reduced for smaller timepiece design, then the timepiece can be more compact and suitable for women's use, but the solar cell and calendar wheel arrangement becomes difficult
Solution Approach 1:
The patent utilizes the vertical dimension (depth) of the movement to arrange components, positioning the solar connection spring between the calendar wheel and solar cell. This three-dimensional arrangement allows compact horizontal dimensions suitable for small timepieces while accommodating all necessary components through strategic vertical layering.
Solution Approach 2:
The patent employs thin-film solar cells that can be positioned in the limited space between the calendar wheel and movement components. The flexible nature of thin-film solar cells allows them to conform to the compact arrangement required for small timepieces while maintaining functionality.
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
This configuration allows for a smaller electronic timepiece with a solar cell, enabling calendar functionality without interference, reducing costs by allowing shared components across various models, and enhancing design flexibility for different sizes and styles.
Implementation Method 1
a solar cell (4) arranged on the inside of the calendar wheel (21) in plan view seen from the character plate (5) side
Data Source
AI summary
An electronic timepiece with a solar cell is provided with a solar cell, a solar cell holding member, a light-transmissive character plate, a ground plate, and a ring-shaped calendar wheel. The solar cell includes a base material that is made of an insulating material, and a light-receiving unit that is arranged on a first surface of the base material. The solar cell holding member is fixedly attached to a second surface of the base material. The light-transmissive character plate is arranged on a timepiece front side of the solar cell. The ground plate is arranged on a back surface of the solar cell. The ring-shaped calendar wheel is disposed between the character plate and the ground plate. The solar cell holding member is arranged on a character plate side of the calendar wheel to position the calendar wheel.