Floating Chronograph Heart Radial Flexure Tolerance Compensation

Resolve Bottlenecks,
Find Innovative SolutionsGenerate Solutions

Solution Overview

Problem

The positioning of a heart-type reset device in chronograph mechanisms requires bulky energy-consuming jumpers or flexible hammers, which are not precise due to manufacturing tolerances, affecting the accuracy of the zero position.

Innovation Solution

A horological mobile with a core mounted floating radially on a shaft, utilizing a flexible element such as a spring or integrated blade to precisely position the heart in the zero position, compensating for shape defects and tolerances without the need for bulky hammers or jumpers.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Measurement precision

If a jumper or flexible hammer is used to position the heart, then the reset function can be achieved, but the device becomes bulky and energy-consuming with reduced precision due to manufacturing tolerances

Engineering Contradiction:

Improvepositioning precision of heartVSAvoidstructure complexity of reset mechanism

Core Design Contradiction:

Measurement precisionVSDevice complexity

Solution Approach 1:

The patent changes the physical state and mechanical parameters of the heart by introducing a flexible element that allows the heart to deform elastically. This enables the heart to adapt its shape to compensate for manufacturing tolerances, achieving precise positioning without complex adjustment mechanisms. The flexible element transforms the heart from a rigid component with fixed dimensions to one that can dynamically adjust its geometric parameters.

Inventive Principle:

Principle #35Parameter changes

Solution Approach 2:

The patent introduces dynamic characteristics to the heart positioning system by making the heart flexible rather than rigid. The heart can now change its shape and position dynamically in response to forces applied during the resetting operation, allowing it to adapt to variations in hammer positioning and achieve consistent zero-positioning accuracy despite manufacturing tolerances.

Inventive Principle:

Principle #15Dynamics

2Ease of manufacture

If a rigid heart is used, then manufacturing is simpler, but positioning accuracy is reduced due to inability to compensate for tolerances

Engineering Contradiction:

Improvemanufacturing simplicity of heartVSAvoidpositioning precision of heart

Core Design Contradiction:

Ease of manufactureVSMeasurement precision

Solution Approach 1:

Inventive Principle:

Principle #35Parameter changes

Solution Approach 2:

The patent converts the harmful effect of manufacturing tolerances into a beneficial adaptive feature. Rather than trying to eliminate tolerances through tighter manufacturing controls, the flexible element allows the heart to naturally compensate for dimensional variations, transforming what was previously a source of positioning error into a mechanism for self-correction and precision achievement.

Inventive Principle:

Principle #22Blessing in disguise (Convert harm into benefit)

3Measurement precision

If a flexible hammer is used to account for tolerances, then positioning accuracy improves, but the hammer becomes bulky and energy-consuming

Engineering Contradiction:

Improvepositioning precision of heartVSAvoidenergy consumption of reset mechanism

Core Design Contradiction:

Measurement precisionVSUse of energy by moving object

Solution Approach 1:

The patent inverts the conventional approach by making the heart flexible instead of the hammer. Rather than using a flexible or articulated hammer to compensate for tolerances, the rigid hammer strikes a flexible heart that deforms to absorb positioning variations. This inversion transfers the flexibility requirement from the actuating mechanism to the receiving component, simplifying the hammer design and reducing its energy consumption while maintaining positioning precision.

Inventive Principle:

Principle #13The other way round (Inversion)

Solution Approach 2:

The patent employs a simple, rigid hammer that can be less precise in its positioning, relying instead on the flexible heart to absorb the positioning errors. The hammer itself becomes a simpler, more durable component that doesn't require complex flexibility mechanisms, effectively trading the durability and simplicity of a rigid hammer for the adaptive precision of a flexible heart.

Inventive Principle:

Principle #27Cheap short-living objects (Disposable)

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

Ensures precise positioning of the heart, adapting to manufacturing defects and maintaining accuracy by providing a flexible and efficient mechanism for resetting chronograph counters, enhancing the accuracy and reliability of timepiece mechanisms.

Implementation Method 1

a spring (60) pushing the core (2) in a radial direction (R) towards said axis (D)

Methodology Applied

Scientific EffectElastic force: Elasticity

Implementation Method 2

sized to dampen an impact applied to a peripheral cam track (23) that comprises said core (2)

Methodology Applied

Scientific EffectImpact damping: Damping

Data Source

PatentEP3101486B1Heart of timepiece or chronograph

Publication Date: 2018.10.03 ETA SA MFG HORLOGERE SUISSE

Figure 1~2
Figure 3~4
Figure 5~6

AI summary

A clockwork mechanism (1) comprising a shaft (3) carrying a wheel (4), and a core (2) angularly indexed in position relative to said wheel (4). This core (2) is mounted to float in a radial direction (R) relative to the axis (D) of said shaft (3) of said mechanism (1), and returned to a neutral position towards said axis (D) by at least one flexible element (6), said flexible element (6) being either a blade (25; 26) integrated into said core (2), or a spring (60) interposed between said wheel (4) and said core (2), and said at least one flexible element (6) being dimensioned to dampen an impact applied to a peripheral cam track (23) comprising said core (2).