MECHANICAL VERSUS ELECTRONICALLY CONTROLLED HYDRAULIC VALVES

摘要

The mechanical hydraulic valve has been the workhorse of low-rise elevator installations for decades. It is a familiar technology that has been proven and refined over the years. However, even the most sophisticated mechanical valves have their drawbacks. The most critical of these is the inability to provide a smooth and consistent ride with fast leveling under changing conditions of load and oil temperature/viscosity.