Watch Depth Measuring Device Using Piston and Gear Train

Resolve Bottlenecks,
Find Innovative Solutions
Generate Solutions

Solution Overview

Problem

Existing diving watches face challenges in integrating depth measurement devices without modifying the watch case or movement, and in triggering chronograph functions at specific depths due to limited space and volume constraints.

Innovation Solution

A depth measurement device using a piston mechanism that transmits external pressure through a gear train to indicate depth, with a compact and precise design that can be integrated into various watch models, and a pressure-sensing system within the crown to automatically start and stop the chronograph at predetermined depths.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Ease of manufacture

If a depth measuring device is integrated into the watch case without modifying the movement, then the ease of manufacture and adaptability improve, but the device complexity increases due to space constraints

Engineering Contradiction:
Improveease of integrationVSAvoiddevice complexity
Core Design Contradiction:
Ease of manufactureVSDevice complexity

Solution Approach 1:

The depth measuring device is nested within the existing watch case structure. The piston mechanism is housed in a chamber formed by the case back and movement, with the circular slide rotating within the casing circle. This nesting approach allows integration without modifying the movement while maintaining manufacturability.

Inventive Principle:
Principle #7Nested doll (Nesting)

Solution Approach 2:

The piston moves in an axial direction perpendicular to the main plane of the watch, converting linear pressure-driven motion into rotational motion of the circular slide through ramp-shaped cams. This dimensional transformation enables compact integration within the constrained watch case volume.

Inventive Principle:
Principle #17Another dimension (Dimensionality change)

2Measurement precision

If a piston mechanism with gear train is used for depth measurement, then the measurement precision improves, but the volume of the device increases

Engineering Contradiction:
Improvedepth measurement accuracyVSAvoiddevice volume
Core Design Contradiction:
Measurement precisionVSVolume of moving object

Solution Approach 1:

The depth measurement function is segmented into distinct components: the piston for pressure sensing, the ramp-shaped cams for motion transformation, the circular slide for rotation, and the gear train for indication. This segmentation allows each component to be optimized for its specific function while maintaining overall compactness.

Inventive Principle:
Principle #1Segmentation

Solution Approach 2:

The piston moves in an axial direction perpendicular to the main plane of the watch, converting linear pressure-driven motion into rotational motion of the circular slide through ramp-shaped cams. This dimensional transformation enables compact integration within the constrained watch case volume.

Inventive Principle:
Principle #17Another dimension (Dimensionality change)

3Ease of manufacture

If the pressure sensor is made small to fit existing watches, then the ease of integration improves, but the force available to trigger chronograph functions decreases

Engineering Contradiction:
Improveease of integrationVSAvoidforce to trigger functions
Core Design Contradiction:
Ease of manufactureVSForce

Solution Approach 1:

The ramp-shaped cams convert the small axial force from the piston into rotational motion with mechanical advantage. The cam profile is designed to provide sufficient force at the appropriate points in the rotation cycle to trigger chronograph functions, dynamically adapting the force transmission to the operational requirements.

Inventive Principle:
Principle #15Dynamics

Solution Approach 2:

The circular slide acts as an intermediary between the piston and the chronograph triggering mechanism. It translates the small linear displacement of the piston into rotational motion that can effectively engage the chronograph control, amplifying the effect of the small input force.

Inventive Principle:
Principle #24Intermediary (Mediator)

4Measurement precision

If transmission elements with gear train are used to transmit piston movement to watch organs, then the measurement precision improves, but the device complexity increases

Engineering Contradiction:
Improvedepth indication precisionVSAvoidtransmission mechanism complexity
Core Design Contradiction:
Measurement precisionVSDevice complexity

Solution Approach 1:

The transmission mechanism is segmented into the circular slide for rotation, the gear train for precise indication, and the chronograph control linkage. This segmentation allows each component to be optimized for its specific function while maintaining overall manageability and precision.

Inventive Principle:
Principle #1Segmentation

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 accurate depth measurement and automatic chronograph control without modifying the watch movement, ensuring high precision, longevity, and ease of integration while respecting the original watch design.

Implementation Method 1

the sensor mechanism comprises at least one piston (343) capable of being moved by external pressure against the effect of a return element

Methodology Applied
Scientific EffectPressure: Pressure Increase

Implementation Method 2

the return element is constituted by a conical or Belleville washer placed between the casing circle and the piston

Methodology Applied
Scientific EffectElasticity: Elasticity

Implementation Method 3

a rolling membrane serving as a sealing element arranged between the piston and the bottom which is provided with openings for water

Methodology Applied
Scientific EffectSealing:

Data Source

PatentEP1960845B1Depth measuring device for watch and watch incorporating such a measuring device
Publication Date: 2018.09.05 OFFICINE PANERAI AG
  • EP1960845B1 patent drawingFigure 1
  • EP1960845B1 patent drawingFigure 2
  • EP1960845B1 patent drawingFigure 3

AI summary

The device has a pressure sensor mechanism (340) comprising a plunger (343) intended to be displaced by hydrostatic pressure against the effect of a Belleville spring washer. The displacement of the plunger is transmitted by a transmission element (342) to a depth needle (307) and a dead needle (308) of a watch. The transmission element has a circular slide (350) pivoting with respect to a casing ring (320) of the watch and a gear chain (359).