Study on Design of Safety Gear for Fall Prevention of Freight Elevator

Abstract

Background/Objectives: This study intends to fine out structure stability through design of a safety gear for fall prevention of freight elevator as a trend of large scaled elevator according to high-rise and advanced buildings.

Methods/Statistical analysis: In order to fabricate a safety gear by applying safety standards and test criteria required by freight elevator and considering mass production, analysis has been proceeded to check design and structure stability of the safety gear using a dedicated structural design software, SOLIDWORKS 2016 and a dedicated analysis software, ANSYS Workbench 18.0.

Findings: Applicable conditions to the safety gear of freight elevator are 5,000[kg] of total allowable load, 60[m/min] or less of rated speed, 16[mm] of guiderail, and 0.2~1[g_n] or less of deceleration. Design and simulation have been carried out using U-spring with 60Si2MnA, hardness is HRC 41~45, and dimensions are thickness 14[mm], height 100[mm], bending length is 80[mm]. Results of finite element analysis of the safety gear with 3D modeling optimization show maximum 1.1502[mm] of total deformation, maximum 0.0043869 of strain, maximum 431.07[MPa] of stress, maximum 15 and minimum 2.7 of safety factor.

Improvements/Applications: We could check operation characteristics and structural safety through design and simulation of the safety gear. We have designed the safety gear considering mass production and assembly so that parts including U-spring can be assembled in a case. It can be applicable to freight and passenger elevator and various kinds of applications including parking tower, dumbwaiter, etc. 

Keywords: safety device, safety