Timepiece Control Device Elastic Arm Jamming Prevention

Resolve Bottlenecks,
Find Innovative Solutions
Generate Solutions

Solution Overview

Problem

Existing timepiece control devices face issues with jamming and premature travel interruption due to toothed mobile collisions, and the use of flexible arms can lead to torque-induced disengagement when operating mechanisms in both directions.

Innovation Solution

A control device with a blocker and abutment or hooking means, controlled by an external member, to prevent disengagement of the toothed mobile from either mobile, allowing operation in both directions without risk of disengagement, and incorporating an elastic arm to facilitate smooth operation and prevent user-induced breakage.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Ease of operation

If the external control member is actuated to bring the toothed mobile into mesh with another mobile, then the mechanism can be switched between positions, but the teeth may abut against each other causing jamming and preventing proper meshing

Engineering Contradiction:
Improveswitching between positionsVSAvoidmeshing reliability
Core Design Contradiction:
Ease of operationVSReliability

Solution Approach 1:

The elastic arm is pre-biased to push the toothed mobile toward the meshing position before the control member completes its actuation. This preliminary action ensures that the teeth are already positioned to engage properly, preventing the abutment problem that occurs when switching between positions.

Inventive Principle:
Principle #10Preliminary action

Solution Approach 2:

The elastic arm acts as a cushioning element that absorbs the shock and misalignment that would otherwise cause the teeth to abut against each other. By providing this beforehand cushioning, the mechanism prevents jamming and ensures smooth meshing when switching between positions.

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

2Stability of the object's composition

If a rigid positioning lever is used to position the toothed mobile, then the meshing position is stable, but the control member blocks before reaching the predefined position and may cause component breakage

Engineering Contradiction:
Improvemeshing position stabilityVSAvoidcontrol member travel
Core Design Contradiction:
Stability of the object's compositionVSEase of operation

Solution Approach 1:

The positioning lever is changed from a rigid structure to an elastic structure. This parameter change allows the lever to deform during the control member's actuation, enabling the control member to complete its full travel without blocking, while still achieving stable meshing position through the lever's elastic recovery.

Inventive Principle:
Principle #35Parameter changes

Solution Approach 2:

The elastic arm provides beforehand cushioning by deforming to absorb the travel interruption that would otherwise block the control member. This cushioning effect allows the control member to reach its predefined position without causing component breakage, while the lever still achieves stable positioning.

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

3Ease of operation

If a flexible arm is used to control the positioning lever, then the operation is smoother and breakage is prevented, but torque may cause the toothed mobile to disengage from the mobile

Engineering Contradiction:
Improveoperation smoothnessVSAvoidmeshing retention
Core Design Contradiction:
Ease of operationVSReliability

Solution Approach 1:

The blocker is positioned to apply a preliminary counteracting force that prevents the torque from causing disengagement. By acting in advance against the potential harmful effect of torque, the blocker ensures the toothed mobile remains engaged with the mobile even when using a flexible arm for smooth operation.

Inventive Principle:
Principle #9Preliminary anti-action

Solution Approach 2:

The blocker acts as an intermediary element between the flexible arm and the toothed mobile. It mediates the torque transmission by providing a blocking action that prevents disengagement, allowing the flexible arm to provide smooth operation without compromising meshing retention.

Inventive Principle:
Principle #24Intermediary (Mediator)

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 smooth operation of both mechanisms in both directions without jamming or disengagement, reducing the risk of component breakage and maintaining the mechanism's integrity.

Implementation Method 1

a positioning lever comprising a first and a second arm, the first arm being elastic, the external control member being arranged to cooperate with the elastic arm so as to tilt the positioning lever in one direction or the other

Methodology Applied
Scientific EffectElasticity: Elasticity

Data Source

PatentEP3486733B1Control device for a timepiece comprising a sliding pinion
Publication Date: 2020.03.25 PATEK PHILIPPE SA
  • EP3486733B1 patent drawingFigure 1
  • EP3486733B1 patent drawingFigure 2a~2b
  • EP3486733B1 patent drawingFigure 3

AI summary

The control device comprises an external moving member (3), a sliding sleeve (12) having a toothed wheel (15), and a movable support (13) on which the toothed wheel is rotatably mounted. The toothed wheel (15) is kinematically connected to the external moving member (3), such that the latter drives the toothed wheel in rotation. The control device further comprises a selector having an external control member (21) manually switchable between two predefined positions, and a positioning lever (23) arranged to be actuated by the external control member to switch in one direction or the other when the external control member (21) switches. The positioning lever (23) has a flexible, elastic arm (25) and is further arranged to act on the sliding sleeve (12) so as to selectively mesh the toothed wheel (15) with one or the other of two wheels (17, 19).