Perpetual Calendar Mechanism Lateral Subsystem Arrangement

Resolve Bottlenecks,
Find Innovative Solutions
Generate Solutions

Solution Overview

Problem

Existing perpetual calendar mechanisms for timepieces are complex, difficult to assemble, and have a large thickness due to the stacking of multiple levels of toothing and control cams, making them cumbersome and inefficient.

Innovation Solution

A perpetual calendar mechanism with a date mobile driven by a synchronization wheel, which is connected to three subsystems via kinematic links, each handling additional steps for months with less than 31 days, February, and February in non-leap years, reducing complexity and thickness by eliminating the need for complex cam and wheel stacking.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Reliability

If multiple levels of toothing and control cams are stacked to achieve perpetual calendar functionality, then the calendar can handle additional steps for months with less than 31 days and leap years, but the device complexity and thickness increase significantly

Engineering Contradiction:
Improveperpetual calendar functionalityVSAvoidcomplexity of programming mobile
Core Design Contradiction:
ReliabilityVSDevice complexity

Solution Approach 1:

The patent divides the perpetual calendar mechanism into three separate subsystems, each handling a specific correction case (months with less than 31 days, February, and February in non-leap years). Each subsystem has its own correction wheel and retractable tooth, allowing independent operation and simplifying the overall structure by eliminating the need for a single complex multi-level programming mobile.

Inventive Principle:
Principle #1Segmentation

Solution Approach 2:

The patent transitions from a vertical stacking arrangement (multiple levels of toothing and cams in the thickness direction) to a lateral arrangement (subsystems positioned side-by-side in the plane of the mechanism). This dimensional change significantly reduces the thickness of the mechanism while maintaining all necessary perpetual calendar functions.

Inventive Principle:
Principle #17Another dimension (Dimensionality change)

2Reliability

If multiple levels of toothing and control cams are stacked to achieve perpetual calendar functionality, then the calendar can handle additional steps for months with less than 31 days and leap years, but the thickness of the mechanism increases

Engineering Contradiction:
Improveperpetual calendar functionalityVSAvoidthickness of mechanism
Core Design Contradiction:
ReliabilityVSLength of stationary object

Solution Approach 1:

The patent transitions from a vertical stacking arrangement (multiple levels of toothing and cams in the thickness direction) to a lateral arrangement (subsystems positioned side-by-side in the plane of the mechanism). This dimensional change significantly reduces the thickness of the mechanism while maintaining all necessary perpetual calendar functions.

Inventive Principle:
Principle #17Another dimension (Dimensionality change)

Solution Approach 2:

The patent divides the perpetual calendar mechanism into three separate subsystems, each handling a specific correction case (months with less than 31 days, February, and February in non-leap years). Each subsystem has its own correction wheel and retractable tooth, allowing independent operation and simplifying the overall structure by eliminating the need for a single complex multi-level programming mobile.

Inventive Principle:
Principle #1Segmentation

3Reliability

If a programming mobile with multiple levels of toothing and control cams is used, then perpetual calendar functionality is achieved, but the difficulty of development and assembly increases

Engineering Contradiction:
Improveperpetual calendar functionalityVSAvoidease of assembly
Core Design Contradiction:
ReliabilityVSEase of manufacture

Solution Approach 1:

The patent divides the perpetual calendar mechanism into three separate subsystems, each handling a specific correction case (months with less than 31 days, February, and February in non-leap years). Each subsystem has its own correction wheel and retractable tooth, allowing independent operation and simplifying the overall structure by eliminating the need for a single complex multi-level programming mobile.

Inventive Principle:
Principle #1Segmentation

Data Source

PatentEP3588201B1Calendar mechanism for timepiece
Publication Date: 2020.12.09 MONTBLANC MONTRE SA
  • EP3588201B1 patent drawingFigure 1
  • EP3588201B1 patent drawingFigure 2
  • EP3588201B1 patent drawingFigure 3a~3b

AI summary

The invention relates to a date mechanism (1) for a timepiece comprising: - a date wheel (3) arranged to be driven by steps at a rate of one step per day by means of a corresponding actuator (9a); characterized in that said mechanism (1) further comprises: - a synchronizing wheel (13) in kinematic connection with said date wheel (3);- a first subsystem (15), a second subsystem (17), and a third subsystem (19) arranged laterally relative to each other and substantially in the same plane, each subsystem (15, 17, 19) comprising a correction wheel (15a, 17a, 19a) kinematically linked to said synchronizing wheel (13) and each carrying a respective retractable tooth (15b, 17b, 19b), as well as a respective control cam (15f, 17f, 19f) arranged to bring said respective retractable tooth (15b, 17b, 19b) into an active position in which it is capable of being driven by a respective actuator (23a, 23b, 23c) at the end of a month, in which: - the control cam (15f) of the first subsystem (15) is arranged to bring said respective retractable tooth (15b) in its active position at the end of each month having less than 31 days;- the control cam (17f) of the second subsystem (17) is arranged to bring said respective retractable tooth (17b) into its active position at the end of each February; and - the control cam (19f) of the third subsystem (19) is arranged to bring said respective retractable tooth (19b) into its active position at the end of each February, which has only 28 days.