Steel Belt Elevator Technologies: A Systematic Review of Patent Trends and Damage Detection Methods

Introduction: Steel-belt traction elevators are increasingly adopted in modern buildings due to their compact structure, enhanced ride comfort, and reduced maintenance needs. Despite their growing use, a systematic understanding of technological innovation trends and damage detection methods remains lacking. Methods: This study combines patent bibliometric analysis with a technical literature review. Patent data were retrieved from the PatSnap Global Patent Database, covering over 6598 records. A targeted search yielded 1,639 valid patents related to steel-belt elevator technologies filed between 1990 and 2025. In parallel, academic literature was surveyed to categorize damage types and damage detection methods for traction belts. Results: Patent filings have increased steadily, with China, the U.S., and Switzerland leading in volume. While China holds the numerical advantage, core innovations are more concentrated in the U.S. and Europe. Damage detection methods primarily target surface and internal defects through techniques, such as electromagnetic sensing, resistance measurement, and computer vision. However, in-field reliability and understanding of damage evolution remain limited. Conclusion: Steel-belt elevator technology is advancing globally, though unevenly. Future work should focus on failure mechanism modeling and integrated, real-time monitoring systems to improve operational reliability and predictive maintenance.