Split-Seconds Lever Isolation Mechanism for Chronograph Friction Reduction

Solution Overview

Problem

Mechanical timepiece split-seconds mechanisms experience energy intake when stopped, leading to energy losses due to friction between the split-seconds lever and the core, which affects the accuracy and efficiency of the chronograph mechanism.

Innovation Solution

A split-seconds isolation mechanism is introduced, utilizing a diaphragm system with a control ring and connecting rods to move the split-seconds lever away from the core, ensuring it remains non-contact regardless of the core's angular position, allowing the mechanism to switch between operational and inactive states to prevent energy intake.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Loss of energy

If the split-seconds mechanism is stopped, then energy losses due to friction are reduced, but the mechanism cannot perform its chronograph function

Engineering Contradiction:

Improveenergy losses due to frictionVSAvoidchronograph function performance

Core Design Contradiction:

Loss of energyVSProductivity

Solution Approach 1:

The patent implements a dynamic isolation mechanism that can switch between two states: an active state where the split-seconds lever contacts the core to enable chronograph function, and an inactive state where the lever is isolated from the core to eliminate friction losses. This dynamic switching capability allows the system to adapt its configuration based on operational requirements, resolving the contradiction between energy efficiency and functional performance.

Inventive Principle:

Principle #15Dynamics

2Ease of operation

If the split-seconds lever is in contact with the core, then the chronograph function operates, but energy losses due to friction occur

Engineering Contradiction:

Improvechronograph operationVSAvoidfriction-related energy losses

Core Design Contradiction:

Ease of operationVSLoss of energy

Solution Approach 1:

The patent extracts the harmful friction interaction between the split-seconds lever and the core by introducing an isolation mechanism. This mechanism can separate the lever from the core when chronograph operation is not required, removing the source of energy loss while preserving the ability to re-establish contact when needed for operation.

Inventive Principle:

Principle #2Taking out (Extraction)

3Loss of energy

If the split-seconds lever is isolated from the core, then energy losses are eliminated, but the chronograph function cannot operate

Engineering Contradiction:

Improveenergy losses due to frictionVSAvoidchronograph mode switching

Core Design Contradiction:

Loss of energyVSAdaptability or versatility

Solution Approach 1:

The patent implements a dynamic isolation mechanism that can switch between two states: an active state where the split-seconds lever contacts the core to enable chronograph function, and an inactive state where the lever is isolated from the core to eliminate friction losses. This dynamic switching capability allows the system to adapt its configuration based on operational requirements, resolving the contradiction between energy efficiency and functional performance.

Inventive Principle:

Principle #15Dynamics

Data Source

PatentEP2897002B1Insulating adjustment mechanism and mechanical timepiece comprising a chronograph mechanism provided with said insulating adjustment mechanism

Publication Date: 2017.05.31 MONTBLANC MONTRE SA

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AI summary

The split-seconds isolation mechanism comprises a split-seconds lever (12), pivoted on a split-seconds wheel (11) coaxial with a chronograph wheel (4), capable of contacting, under the action of a lever spring (13), a core (6) integral with the chronograph wheel (4). It includes a diaphragm device having several connecting rods (26) linking a control ring (20) concentric with the split-seconds wheel (11) to several moving parts (27, 28, 29), each having a central portion in the shape of an arc of a circle such that an angular displacement of the control ring causes the central portions (28) of the moving parts (27, 28, 29) to move closer to or further from the axis (5) of the chronograph wheel.