Timepiece Display Device with Magnetic Coupling for Oscillation Damping

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Solution Overview

Problem

Existing timepiece display systems face issues with oscillation during display coupling and high energy consumption, particularly when aligning or separating displays, which affects the smooth movement and efficiency of watch hands, especially in functions like compass mode.

Innovation Solution

Implementing contactless magnetic or electrostatic coupling means on the displays and their transmission mechanisms, allowing them to attract and create a torque only in specific positions, thereby dampening oscillations without permanent friction, and enabling disengagement under control for efficient operation.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Stability of the object's composition

If an elastic friction washer is interposed in the gear train to dampen oscillation, then the oscillation is completely dampened, but energy consumption increases

Engineering Contradiction:
Improveoscillation dampeningVSAvoidenergy consumption
Core Design Contradiction:
Stability of the object's compositionVSUse of energy by moving object

Solution Approach 1:

The patent applies periodic action by using magnetic coupling that is activated only during specific phases of the display operation (during alignment and coupling phases) rather than continuously. The magnetic field is engaged temporarily to dampen oscillations during needle pivoting, then disengaged during normal operation to conserve energy, creating a periodic on/off action that addresses oscillation only when needed.

Inventive Principle:
Principle #19Periodic action

Solution Approach 2:

The patent replaces the mechanical friction-based damping system (elastic friction washer in gear train) with a magnetic field-based coupling system. Instead of using continuous mechanical friction to dampen oscillations, the invention uses contactless magnetic attraction and repulsion forces between magnetized elements to achieve the same damping effect without the energy loss associated with mechanical friction.

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

2Stability of the object's composition

If the needle is moved rapidly to eliminate oscillation, then oscillation is eliminated, but this cannot be achieved with a single-phase motor

Engineering Contradiction:
Improveoscillation eliminationVSAvoidneedle movement speed
Core Design Contradiction:
Stability of the object's compositionVSSpeed

Solution Approach 1:

The patent introduces a magnetic field as an intermediary force between the motor and the display needle. The magnetic coupling acts as a mediator that provides additional damping force during needle movement, allowing the single-phase motor to achieve smooth positioning without requiring excessive speed. The magnetic field mediates the interaction between the driving force and the needle, enabling controlled movement that eliminates oscillation.

Inventive Principle:
Principle #24Intermediary (Mediator)

3Stability of the object's composition

If mechanical coupling between displays is performed by friction using springs, then coupling is achieved, but energy loss increases

Engineering Contradiction:
Improvedisplay couplingVSAvoidenergy loss during coupling
Core Design Contradiction:
Stability of the object's compositionVSLoss of energy

Solution Approach 1:

The patent replaces the mechanical spring-based friction coupling system with a magnetic field-based coupling system. Instead of using physical springs and friction surfaces to couple displays, the invention uses magnetic attraction forces between magnetized elements on different displays to achieve coupling. This contactless magnetic coupling eliminates the energy loss associated with mechanical friction and spring deformation while maintaining stable display coupling.

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

4Stability of the object's composition

If magnetic coupling is used between motor means and display, then coupling is achieved, but friction forces alter mechanism performance

Engineering Contradiction:
Improvemagnetic couplingVSAvoidenergy loss due to friction
Core Design Contradiction:
Stability of the object's compositionVSLoss of energy

Solution Approach 1:

The patent applies magnetic coupling between motor means and display elements, replacing mechanical friction-based coupling. The magnetic field provides the necessary coupling force without physical contact, eliminating friction losses that would otherwise occur in mechanical coupling systems. The magnetized elements attract or repel each other through the magnetic field, achieving stable coupling without energy dissipation through friction.

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

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 solution reduces energy consumption and maintains efficient movement by damping oscillations only when necessary, ensuring smooth alignment and separation of displays while minimizing energy loss, particularly in functions like compass mode.

Implementation Method 1

cooperate in a complementary manner in contactless coupling by attraction

Methodology Applied
Scientific EffectMagnetic coupling by attraction: Magnetism

Implementation Method 2

cooperate in a complementary manner in contactless coupling by attraction

Methodology Applied
Scientific EffectElectrostatic coupling by attraction: Electrostatics

Implementation Method 3

creating a force or an additional torque between said first display and the second display so as to dampen their oscillation

Methodology Applied
Scientific EffectOscillation damping: Damping

Data Source

PatentEP2602674B1Timepiece display device with combined display means
Publication Date: 2014.06.25 ETA SA MFG HORLOGERE SUISSE
  • EP2602674B1 patent drawingFigure 1~3

AI summary

A clockwork display device (100) comprising a first display (1) cooperating via first transmission means (11) with first drive means (10), and a second display (2) cooperating via second transmission means (21) with second drive means (20). First non-contact coupling means (12) are carried by said first display (1) or by said first transmission means (11), second non-contact coupling means (22) are carried by said second display (2) or by said second transmission means (21), said first coupling means (12) cooperate in a complementary non-contact coupling by attraction with said second coupling means (22) so as, when they are located in the immediate vicinity of each other, to synchronize the movement of said first display (1) and said second display (2).The said first (12) and second (22) coupling means are magnetic or electrostatic.