Watch Hairspring Temperature Compensation for Stable Resonator Frequency
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Mechanical resonators in watches are prone to frequency variations due to external parameters such as temperature, pressure, and gravity, leading to inaccuracies in time measurement.
Innovation Solution
A spring-spiral regulating organ with an elastic temperature compensation device that adjusts its stiffness according to temperature changes by using a bimetallic strip to apply a variable force or torque on an elastic element, modifying the resonator's behavior to maintain precision.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Measurement precision
If a traditional balance spring is used without temperature compensation, then the device complexity is low, but the measurement precision deteriorates due to frequency variations caused by temperature changes
Solution Approach 1:
The elastic temperature compensation element is integrated within the existing balance spring structure. The element is inserted into the inner turns of the balance spring, forming a nested configuration where the compensation element is housed within the coils of the main spring. This nesting approach allows temperature compensation functionality to be added without significantly increasing overall device complexity or requiring separate compensation mechanisms.
Solution Approach 2:
The invention changes the physical parameters of the balance spring system by introducing an elastic element with temperature-dependent stiffness properties. The elastic element's stiffness varies with temperature, automatically adjusting the overall spring characteristics to compensate for temperature-induced frequency variations. This parameter change approach maintains measurement precision across different temperatures without complex control systems.
2Measurement precision
If temperature compensation means are added to the balance spring, then the measurement precision improves, but the device complexity increases due to additional components
Solution Approach 1:
The invention merges the temperature compensation function with the existing balance spring structure. The elastic element is combined with the balance spring's inner turns, creating a unified system where the compensation function is integrated rather than added as a separate mechanism. This merging reduces the overall complexity compared to independent compensation devices while maintaining improved measurement precision.
Solution Approach 2:
The elastic temperature compensation element operates autonomously based on temperature changes. It automatically adjusts its stiffness according to the ambient temperature, providing self-regulating temperature compensation without requiring external control mechanisms, sensors, or additional actuation systems. This self-service approach improves precision while minimizing added complexity.
3Measurement precision
If the elastic element stiffness is increased to compensate for temperature effects, then the measurement precision improves, but the force required to operate the resonator increases
Solution Approach 1:
The invention applies local quality by positioning the elastic temperature compensation element specifically at the outer end of the balance spring, where it can most effectively influence the spring's overall characteristics. The element is inserted into the inner turns, creating a localized modification that optimizes its compensating effect while minimizing the overall force requirements. This localized placement allows precision improvement without proportionally increasing the operating force.
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
The solution ensures precise operation of the resonator by fine-tuning its frequency adjustment in response to temperature fluctuations, enhancing timekeeping accuracy.
Implementation Method 1
using a bimetallic strip to apply a variable force or torque on an elastic element, modifying the resonator's behavior to maintain precision
Implementation Method 2
an elastic device comprising an elastic element connecting the external end to a first support fixed relative to the clock movement
Data Source
Figure 1~2
AI summary
The invention relates to a regulating organ (1) for a watch movement comprising an oscillating mass, for example a balance wheel, a balance spring comprising a flexible ribbon (2) wound on itself in several turns, the ribbon (2) having a predefined rigidity to allow the oscillating mass to perform a rotary oscillatory movement, the ribbon (2) comprising an external end (9), characterized in that the regulating organ (1, 10) comprises an elastic temperature compensation device configured to adapt its stiffness according to the temperature in order to compensate for the effect of the temperature on the regulating organ (1, 10), the elastic device comprising an elastic element (5) connecting the external end (9) to a first support fixed (7) with respect to the watch movement, as well as pre-stressing means (6) for applying a variable force or torque on the elastic element (5) according to the temperature.The invention also relates to a clockwork movement comprising such a regulating organ (1).