Watch Strap Connecting Link With Elastic Return Means

Resolve Bottlenecks,
Find Innovative Solutions
Generate Solutions

Solution Overview

Problem

Traditional watch bracelet connections with bars exhibit play and clearance issues due to non-rigid construction and visible gaps between the watch case and the connecting link, leading to poor retention and aesthetic concerns.

Innovation Solution

A connecting link with integrated elastic return means, including a cover with elastic arms and pivots that move between compressed and rest positions, eliminates play by ensuring perfect co-axiality and wider machining tolerances, allowing for a more robust and aesthetically pleasing assembly.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Adaptability or versatility

If traditional spring bars with sliding pieces and cylindrical bodies are used, then the bar can accommodate movement and assembly, but the construction is not rigid and has play between parts

Engineering Contradiction:
Improveassembly accommodationVSAvoidrigidity
Core Design Contradiction:
Adaptability or versatilityVSStability of the object's composition

Solution Approach 1:

The patent employs elastic arms that can dynamically adjust between a compressed state during assembly and an extended state during operation. This dynamic behavior allows the connecting link to accommodate assembly movements while maintaining rigid retention during wear, eliminating the play characteristic of traditional sliding-piece constructions.

Inventive Principle:
Principle #15Dynamics

Solution Approach 2:

The connecting link is divided into distinct functional segments: elastic arms for retention, pivots for positioning, and a rigid body for structural support. This segmentation allows each component to perform its specific function optimally - the elastic arms provide adaptability while the rigid body ensures stability, resolving the contradiction between flexibility and rigidity.

Inventive Principle:
Principle #1Segmentation

2Ease of operation

If lateral clearances are provided in the connecting link for bracelet mounting, then assembly and dismounting is enabled, but the retention quality is reduced

Engineering Contradiction:
Improveassembly easeVSAvoidretention quality
Core Design Contradiction:
Ease of operationVSReliability

Solution Approach 1:

The elastic arms transition from a compressed state during assembly (allowing lateral clearance for easy mounting) to an extended state during operation (providing strong retention). This dynamic transformation enables the connecting link to simultaneously achieve ease of assembly and high retention quality without compromising either attribute.

Inventive Principle:
Principle #15Dynamics

3Manufacturing precision

If precise initial positioning between the connecting link strip and housing is required, then co-axiality can be guaranteed, but assembly complexity increases

Engineering Contradiction:
Improveco-axialityVSAvoidassembly complexity
Core Design Contradiction:
Manufacturing precisionVSDevice complexity

Solution Approach 1:

The pivots serve a dual function: they are both structural components and self-aligning elements. During assembly, the pivots automatically position themselves to ensure co-axiality between the connecting link and housing without requiring precise initial positioning or complex alignment procedures. This self-service mechanism eliminates the need for complex assembly processes while guaranteeing manufacturing precision.

Inventive Principle:
Principle #25Self-service

Solution Approach 2:

The patent changes the geometric parameters of the pivots (cylindrical or truncated conical shapes) to enable self-alignment. These parameter modifications allow the pivots to automatically achieve co-axial positioning during assembly, reducing assembly complexity while maintaining high manufacturing precision.

Inventive Principle:
Principle #35Parameter changes

4Adaptability or versatility

If multiple small sliding pieces and a cylindrical body with spring are used, then the bar can function, but the number of components increases

Engineering Contradiction:
Improvefunctional capabilityVSAvoidcomponent count
Core Design Contradiction:
Adaptability or versatilityVSDevice complexity

Solution Approach 1:

The patent merges multiple traditional components (spring, sliding pieces, cylindrical body) into an integrated elastic arm structure. The elastic arms incorporate the retention function of the spring, the positioning function of the sliding pieces, and the structural function of the cylindrical body, thereby reducing the total component count while maintaining full functional capability.

Inventive Principle:
Principle #5Merging (Combining)

Solution Approach 2:

The elastic arms perform multiple functions simultaneously: they provide elastic retention like a spring, enable lateral movement like sliding pieces, and maintain structural integrity like a cylindrical body. This multi-functionality eliminates the need for separate specialized components, reducing device complexity while preserving adaptability.

Inventive Principle:
Principle #6Universality (Multi-functionality)

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 provides a secure, rigid connection between the watch case and bracelet, eliminating visible play and simplifying assembly, while allowing for easier machining and reduced component count, resulting in improved retention and a more integrated look.

Implementation Method 1

elastic return means including a cover (30) provided with elastic arms (32) in the link (10), the elastic arms (32) separating two pivots mounted movable inside the passage, along the longitudinal axis of the passage and capable of evolving each between a compressed position and a rest position

Methodology Applied
Scientific EffectElasticity: Elasticity

Data Source

PatentEP3333643B1Attachment device
Publication Date: 2020.02.05 THE SWATCH GRP RES & DEVELONMENT LTD
  • EP3333643B1 patent drawingFigure 1~2
  • EP3333643B1 patent drawingFigure 3~4
  • EP3333643B1 patent drawingFigure 5

AI summary

The invention relates to a device for attaching a watch strap to a watch case by means of a connecting link. The watch case comprises a case middle, at least one pair of lugs, and a case back. The connecting link includes a passage for attaching the strap to the watch case. According to the invention, the attachment means are integrated into the connecting link and comprise elastic return means separating two pivots mounted movably within the passage. Each pivot is capable of moving between a compressed position and a rest position in which the pivots are arranged to rest in a hole formed in each lug of the watch case.