APPARATUS FOR MEASURING EFFECTIVE FLEXURAL RIGIDITY OF GUIDE RAIL OF ELEVATOR

PURPOSE:To measure effective flexural rigidity simply with relatively good accuracy by applying vibration force to a guide rail in a direction perpendicular thereto and by measuring natural frequency of lateral vibration of the guide rail at this time. CONSTITUTION:An electric signal is sent from a control box 14 to a vibration applying device 8, which applies vibration force of variable frequency to a guide rail 1 to cause lateral vibration in a horizontal direction on the rail 1. By measuring magnitude of vibration at this time by a vibration measuring device 9, natural frequency f0 on the rail 1 is measured. Since there is correlation between the frequency f0 and a spring constant (k) of horizontal deflection, the value f0 can be converted into a constant K0. When a spring constant at an optional floor is kH, an increase/decrease of flexural rigidity can be estimated with a constant ratio kH/k0. Since in general the value f0 is proportional to a square root of the constant (k), measurement of natural frequency f0H at an optional floor position and natural frequency f00 without any compression load applied to the rail 1 permits estimation of an increase/decrease in flexural rigidity from (f0H/f00) (=kH/k0).