(1) Traction wheel position deviation: The front and rear (towards the counterweight) directions should not exceed ± 2mm, and the left and right directions should not exceed ± 1mm.
(2) The verticality error of the traction wheel should not exceed 2.0mm.
(3) The parallelism error between the traction wheel and the guide wheel or the winding wheel shall not exceed ± 1mm.
Influencing Factors Balance Coefficient
Due to the fact that the drag force is generated by the combined gravity of the car and the counterweight acting on the traction wheel rope groove through the traction rope, the counterweight is a necessary condition for the friction force between the traction rope and the traction wheel rope groove. With it, it is easy to balance the weight of the elevator car with the weight of the payload, which can also reduce the power consumption of the transmission device during elevator operation. Therefore, counterweight, also known as balance weight, is suspended at the other end of the traction wheel relative to the car, playing a role in balancing the weight of the car.
When the weight on the side of the elevator car is equal to the weight on the opposite side, T1=T2, If the weight change of the steel wire rope is not considered, the traction machine can easily operate by overcoming various frictional resistances. But in reality, the weight of the car changes with the cargo (passengers), so a fixed counterweight cannot completely balance the weight of the car under various loads. Therefore, the weight to weight matching will directly affect the drag force and transmission power.
In order to ensure that the absolute value of the load torque of the elevator is basically equal under full load and empty load conditions, the national standard stipulates a balance coefficient K=0.4-0.5, which means balancing 40% to 50% of the rated load. Therefore, the total weight of the counterweight side should be equal to the self weight of the car plus 0.4 to 0.5 times the rated load capacity. This 0.4-0.5 is the equilibrium coefficient.
When K=0.5, the load torque of the elevator is zero at half load. The car and counterweight are completely balanced, and the elevator is in optimal working condition. When the elevator load changes from no-load to rated load, the torque change reflected on the traction wheel is only 50%, reducing energy consumption and lowering the burden on the traction machine.
