Pilot valve with adjustable switch pressure differential - has connection between pressure valve and servo control space

摘要

A pressure cut-off valve (100) connected to a pressure medium and a tank (T) has a main valve (101), a servo valve (102 or I) and a pressure control valve (103 or II). The control space (20) of the main valve (101) is connected with the tank (T) when the closing mechanism (8) of the servo valve (102) is held in the open position by a piston (4) acted on by control medium. The control space (21) of the servo valve piston (4) has a line (12) incorporating a restrictor (14) to the service (A), and is linked to the pressure valve (103 or II) which connects it with the tank (T) at a fixed control pressure. USE - Permits accurate adjustment of switch pressure differential.