Magnetic Escapement with Stop Means for Shock Protection

Resolve Bottlenecks,
Find Innovative Solutions
Generate Solutions

Solution Overview

Problem

Escapement mechanisms in timepieces are sensitive to shocks and overtorques, and existing mechanical contact-based systems lack efficiency and safety.

Innovation Solution

The use of magnetic or electrostatic fields to transmit torque between a retainer and an escapement wheel set, with stop means to prevent mechanical contact and ensure safe operation under high torque conditions, combining a magnetic or electrostatic escapement with a mechanical one to maintain functionality.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Loss of energy

If magnetic or electrostatic fields are used to transmit torque without mechanical contact, then efficiency is improved and wear is reduced, but sensitivity to shocks and overtorques increases

Engineering Contradiction:
ImproveefficiencyVSAvoidsensitivity to shocks and overtorques
Core Design Contradiction:
Loss of energyVSReliability

Solution Approach 1:

The patent replaces the traditional mechanical contact-based torque transmission system with a magnetic or electrostatic field-based system. The retainer uses magnetic poles or electrostatic charges to interact with the escapement wheel set without physical contact, eliminating friction and wear while maintaining efficient torque transmission. This substitution directly addresses the efficiency improvement while the stop means provide mechanical backup for reliability.

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

Solution Approach 2:

The patent incorporates stop means (mechanical stops or limits) that engage before the magnetic or electrostatic actuators can be damaged by excessive torque or shocks. These stop means act as a protective mechanism that limits the maximum force or displacement, preventing damage to the contactless actuation system while allowing normal operation to proceed without interference.

Inventive Principle:
Principle #11Beforehand cushioning (Prior cushioning)

2Reliability

If mechanical contact is used between retainer and escapement wheel set, then safety against shocks and overtorques is improved, but efficiency decreases due to friction and wear

Engineering Contradiction:
Improvesafety against shocks and overtorquesVSAvoidefficiency
Core Design Contradiction:
ReliabilityVSLoss of energy

Solution Approach 1:

The patent replaces continuous mechanical contact with contactless magnetic or electrostatic interaction for torque transmission. The retainer uses magnetic poles or electrostatic charges to attract or repel the escapement wheel set, eliminating sliding friction and wear that occur in traditional mechanical escapements. This substitution directly improves efficiency by reducing energy loss to friction while the stop means provide mechanical safety backup.

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

3Loss of energy

If contactless magnetic or electrostatic actuation is used, then wear is reduced and efficiency is improved, but protection against shocks and overtorques becomes insufficient

Engineering Contradiction:
ImproveefficiencyVSAvoidprotection against shocks and overtorques
Core Design Contradiction:
Loss of energyVSObject-affected harmful factors

Solution Approach 1:

The patent replaces mechanical contact-based actuation with contactless magnetic or electrostatic fields. The retainer uses magnetic poles or electrostatic charges to transmit torque to the escapement wheel set without physical contact, eliminating wear and reducing energy loss to friction. This substitution improves efficiency while the stop means provide mechanical protection against extreme conditions.

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

Solution Approach 2:

The patent incorporates stop means that engage before the contactless actuation system can be damaged by excessive torque or shocks. These mechanical stops or limits act as a protective barrier, preventing the magnetic or electrostatic actuators from experiencing forces beyond their design limits, thereby providing the necessary protection against harmful factors.

Inventive Principle:
Principle #11Beforehand cushioning (Prior cushioning)

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 enhances efficiency and safety by preventing stalling and maintaining operation under high torque conditions, offering a constant force system and improved chronometric properties while ensuring protection against shocks and overtorques.

Implementation Method 1

at least the first pole mass 310 and/or the first track 21 creates a first magnetic or electrostatic field in a first air gap 210

Methodology Applied
Scientific EffectMagnetic field: Magnetic Field

Implementation Method 2

at least the first pole mass 310 and/or the first track 21 creates a first magnetic or electrostatic field in a first air gap 210

Methodology Applied
Scientific EffectElectrostatic field: Electric Field

Implementation Method 3

at least the second pole mass 320 and/or the second track 42 creates a second magnetic or electrostatic field in a second gap 420

Methodology Applied
Scientific EffectMagnetic field: Magnetic Field

Implementation Method 4

at least the second pole mass 320 and/or the second track 42 creates a second magnetic or electrostatic field in a second gap 420

Methodology Applied
Scientific EffectElectrostatic field: Electric Field

Data Source

PatentEP2894522B1Optimised escapement with security system
Publication Date: 2019.01.30 NIVAROX FAR SA
  • EP2894522B1 patent drawingFigure 1~3

AI summary

Escapement mechanism (1) comprising a stop (3) comprising a first actuator (31) cooperating with a resonator (2) and a second actuator (32) cooperating with an escapement wheel (4) subjected to a driving torque less than a nominal torque. The first actuator (31) comprises a magnetized or electrified pole mass (310), the resonator (2) comprises a magnetized or electrified track (21), and the pole mass (310) and/or the track (21) creating, in an air gap (210) between the pole mass (310) and the track (21), a magnetic or electrostatic field having an intensity ensuring the relative drive of the stop (3) and the resonator (2) when the torque is less than the nominal torque, and the stop (3) and/or the resonator (2) comprise stopping means (211; 311) limiting the relative travel between the actuator (31) and the resonator (2) when the torque is greater than the nominal torque.