METHOD AND DEVICE FOR DETECTING NON-UNIFORM AND UNIFORM DETERIORATIONS IN A SUSPENSION MEMBER ARRANGEMENT FOR AN ELEVATOR BASED ON AC VOLTAGE MEASUREMENTS

• Main Authors: HENNEAU, Philippe, ROBIBERO, Vincent
• Format: Patent
• Language: English; French; German
• Published: 10.01.2024
• Subjects: ELEVATORS; ESCALATORS OR MOVING WALKWAYS; HAULING; HOISTING; LIFTING; MEASURING; MEASURING ELECTRIC VARIABLES; MEASURING MAGNETIC VARIABLES; PERFORMING OPERATIONS; PHYSICS; TESTING; TRANSPORTING

A method and a device for detecting non-uniform and uniform deterioration states in an elevator's suspension member arrangement (9) comprising at least one suspension member (11) having a first and a second group (24a, 24b) of electrically conductive cords (23) is proposed. First ends (25a,b) of the groups of cords (23) are electrically connected to an alternating voltage generator arrangement (G, G1, G2). Second ends (27a, b) of the first and second group (24a, 24b) are electrically connected to each other via a neutral point (30) at which electrical resistances to a first and second voltage generators (G1, G2), respectively, are same in a non-deteriorated state of the suspension member arrangement (9). First and second resistors (Ra, Rb) are arranged between the neutral point (30) and the second ends (27a, 27b), respectively. The method comprises: applying the first alternating voltage U1 to the first end (25a) of the first group (24a) and applying the second alternating voltage U2 to the first end (25b) of the second group (24b); determining a neutral point voltage Un between the neutral point (30) and an electrical reference potential (34); determining a difference voltage Ud between a first difference measurement point (57), located between the second end (27a) of the first group (24a) and the first electrical resistor (Ra), and a second difference measurement point (59), located between the second end (27b) and the second electrical resistor (Rb); determining the deterioration state based on both the determined neutral point voltage Un and the determined difference voltage Ud. Both, non-uniform as well as uniform deteriorations throughout the suspension member arrangement (9) may be determined using a simple measurement device (17) including two voltage determining units (35, 40) arranged at a same end of the suspension members (11).