Dual-Mode Retractable Reel Mechanism – Mechanical Design and CAD Engineering

This project involves the full mechanical design and CAD development of a dual-mode retractable reel mechanism. The device is based on a standard badge-holder-style reel, but will be enhanced with a custom internal mechanism that enables two selectable operating modes:

➤ Mode 1: Standard Retraction

Cord extends and retracts normally via internal power spring

No locking behavior; automatic retraction on release

➤ Mode 2: Controlled Extension Lock

Cord can be pulled to approximately 75% of its full length

Upon release, cord remains loose in that extended position

A secondary pull will trigger full retraction

Only a single lock point is allowed (not multiple per revolution)

A mechanical mode-switching element (e.g., lever, tab, or twist switch) will toggle between Mode 1 and Mode 2. The entire solution must be fully mechanical, compact, and designed for ease of assembly and low-cost manufacturing.

Deliverables:
Phase 1 – Concept Development

Conceptual sketches or mechanism diagrams

Mechanical logic for Mode 2 locking and trigger behavior

Description of the mode-switching solution

Optional short animation or simulation to illustrate function

Phase 2 – CAD + Engineering Package

Full SolidWorks 3D CAD assembly

STL or STEP files for 3D printing / prototyping

Production-ready 2D drawings with tolerances, exploded views

Designed with assembly simplicity and mass production in mind