Moon Phase Watch Gear Mechanism for Accurate Lunar Indication

Resolve Bottlenecks,
Find Innovative Solutions
Generate Solutions

Solution Overview

Problem

Existing moon phase display watches require users to estimate the moon phase by positioning the sun, leading to potential errors in determining the correct phase.

Innovation Solution

A moon phase display watch with a sun plate and moon hand mechanism, where the sun plate makes one rotation per day and the moon hand makes approximately 28.53059 rotations over a synodic month, using a planetary gear mechanism and correction mechanism to accurately indicate the moon phase with minimal error.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Device complexity

If the user estimates the moon phase by positioning the sun themselves, then the device structure can be simpler, but the measurement precision of moon phase determination deteriorates

Engineering Contradiction:
Improvedevice structureVSAvoidmoon phase determination accuracy
Core Design Contradiction:
Device complexityVSMeasurement precision

Solution Approach 1:

The watch mechanism automatically performs the complex calculation and positioning of moon phases without requiring user estimation or manual operation. The gear system self-regulates to maintain accurate moon phase indication based on the sun's position, eliminating the need for user intervention in the measurement process.

Inventive Principle:
Principle #25Self-service

Solution Approach 2:

The patent replaces manual mechanical positioning and user estimation with an automated gear-based mechanical system. The planetary gear mechanism automatically tracks the sun's motion and calculates moon phase positions, substituting human cognitive estimation with precise mechanical computation.

Inventive Principle:
Principle #28Mechanics substitution (Replace mechanical system)

2Reliability

If the moon phase is indicated with high precision, then the reliability of moon phase indication improves, but the device complexity increases

Engineering Contradiction:
Improvemoon phase indication accuracyVSAvoidmechanism complexity
Core Design Contradiction:
ReliabilityVSDevice complexity

Solution Approach 1:

The patent introduces intermediate gear mechanisms that serve as mediators between the sun tracking function and the moon phase indication function. These intermediate gears (including the sun moon intermediate wheel with multiple gears) translate the sun's daily motion into the precise monthly moon phase cycle, breaking down the complex transformation into manageable mechanical steps.

Inventive Principle:
Principle #24Intermediary (Mediator)

Solution Approach 2:

The moon phase indication mechanism is segmented into multiple functional components: the sun wheel for daily tracking, the moon wheel for monthly cycling, and intermediate wheels for ratio transformation. This segmentation allows each component to handle a specific aspect of the calculation, making the overall complex system more manageable and maintainable.

Inventive Principle:
Principle #1Segmentation

Data Source

PatentEP3719585B1Moon phase display watch
Publication Date: 2024.10.16 SEIKO EPSON CORP
  • EP3719585B1 patent drawingFigure 1
  • EP3719585B1 patent drawingFigure 2
  • EP3719585B1 patent drawingFigure 3

AI summary

A moon phase display watch of the present disclosure includes a first member configured to make one rotation per day, a second member configured to rotate coaxially with the first member and to make M-1 rotations every M days, the M days being a period of a synodic month, a moon phase indicating part provided at one of the first member and the second member, the moon phase indicating part being configured to indicate a moon phase, and a moon phase pointing part provided at the other of the first member and the second member, the moon phase pointing part being configured to point to the moon phase indicating part.