Timepiece Rate Measurement via Magnetic Sensor
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Conventional timepieces with continuous rotation electromechanical transducers face challenges in measuring the rate accurately due to variable rotational speeds, requiring longer measurement periods compared to those with stepping motors, and the lack of a perfectly periodic event detectable from outside, making precise rate measurement difficult without opening the watch case.
Innovation Solution
A method involving the measurement of medium frequency derived from a digital signal generated by an electronic time base, using a kinematic chain with a continuous rotation electromechanical transducer, where regulation impulses are supplied to regulate rotational speed, allowing for precise measurement without galvanic contact, by detecting time intervals between regulation impulses and calculating the medium frequency.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Ease of operation
If a continuous rotation electromechanical transducer is used in the timepiece, then the time display can be driven, but the rotational speed varies making precise rate measurement difficult
Solution Approach 1:
The patent introduces an intermediary periodic signal generated by an electronic time base that mediates between the variable rotational speed of the electromechanical transducer and the measurement system. This periodic signal provides a stable reference that can be detected externally, allowing precise rate measurement despite the variable speed of the transducer itself.
Solution Approach 2:
The patent replaces direct mechanical detection of the transducer's rotational position with an electronic signal-based measurement system. Instead of mechanically detecting the variable speed, the system uses electronic periodic signals and magnetic field detection to measure the rate, substituting mechanical measurement with electronic measurement.
2Reliability
If measurement is performed without opening the watch case, then the timepiece remains sealed and functional, but detecting periodic events from outside becomes challenging
Solution Approach 1:
The patent uses magnetic field variations as an intermediary that can transmit information about the internal periodic events through the sealed case. The magnetic sensor detects these field variations externally without requiring physical access to internal components, maintaining the seal while enabling measurement.
Solution Approach 2:
The patent substitutes mechanical detection methods with magnetic field detection. Instead of mechanically accessing internal components to detect periodic events, the system uses magnetic sensors to detect field variations caused by the electromechanical transducer's operation, enabling non-invasive measurement.
3Ease of operation
If a magnetic sensor is used to detect regulation impulses from outside, then non-contact measurement is achieved, but the variable rotational speed causes measurement inaccuracies
Solution Approach 1:
The patent introduces a periodic electronic signal from the time base that regulates the electromechanical transducer at fixed intervals. This periodic action creates regularly spaced magnetic field variations that can be detected accurately, overcoming the irregularity caused by variable rotational speed. The measurement system synchronizes with this periodic signal to achieve precise timing.
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
Enables precise measurement of the timepiece rate with improved accuracy and efficiency, reducing the measurement period significantly, allowing for accurate rate determination even when the rotational speed is variable, thus addressing the limitations of existing methods.
Implementation Method 1
In motor mode, to switch from an electric current to a mechanical drive force of a time display mechanism, it is envisaged that such an electric current circulates in at least one coil so as to generate a magnetic field which is coupled with permanent magnets borne by the rotor. In generator mode, to switch from a mechanical drive force of the generator rotor to an electric current, which may power an electronic circuit for regulating the medium rotational speed of the rotor, a force couple rotates the rotor wherein the magnets then induce an electric current in the stator coil.
Implementation Method 2
measurement apparatuses exist arranged to make precise time measurements between the steps of the motor, using a magnetic sensor capable of precisely detecting a certain time relative to each of the electrical impulses supplied to the stepping motors for the driving thereof. The electrical impulses induce magnetic impulses in the stator of the motor to rotate the rotor thereof which is equipped with at least one permanent magnet. The magnetic impulses are propagated partially outside the stator and they may be detected by a magnetic sensor outside the watch.
Data Source
AI summary
A method for measuring the medium frequency of a digital signal derived from a reference periodic signal generated by an electronic oscillator (quartz oscillator) forming a timepiece (2) which includes an analogue time display device and a continuous rotation electromechanical transducer (generator or continuous rotation motor) which is kinematically linked to this display device and wherein the medium rotational speed is regulated by a regulation device. The medium frequency of the digital signal is determined by a measurement device (70) without galvanic contact with the movement of the timepiece. The measurement method makes it possible to determine the rate of the timepiece and the precision of the electronic oscillator based on regulation impulses detected by a magnetic sensor (72) and over a measurement period limited to the duration of an inhibition cycle of periods of the reference periodic signal.