Controlling the flow of water to machine tools by fitting a first pressure switch which closes when the pressure is above a minimum and a second which closes when the pressure is below a maximum

摘要

The flow of lubricating water to a machine tool may be controlled by installing two pressure operated switches (A,B) in the water supply line. The first switch (A) closes when the pressure is above a minimum and the second switch (B) closes when the pressure is below a maximum. The two switches are connected in series and a closed circuit indicates correct operation