Flame cutter - has identical two=way valves in oxygen supplies and three=way valve for fuel gas supply for gas pressure control

摘要

In the control system for a flame cutter, the valves (17,18) in the O2 supply lines are identical two-way valves. The valve (16) in the fuel gas line is a three-way valve. Pref. the O2 supply valves (17,18) each have two selectable electro-magnetic valves (46.49) and sensors (50,51) with electronic valve controls (19,20). One electro-magnetic valve (46,48) is between the inflow openings and the control zones of the regulating pistons, and the other electro-magnetic valve (47,49) is between the control zones and the relief outlets. The sensors (50,51) generate actual value signals for the values in the low-pressure valve chambers, which are constantly compared with nominal values from the flame cutter control (12) by the electronic valve controls. According to the signal for the difference between actual and nominal values, the electro-magnetic valves (46,49) are opened or closed to raise or lower the oxygen supply (38,39) pressure. The valve (16) in the fuel gas supply has a control magnet (84) and a sensor (85) with an electronic magnet control (21). The control magnet (84) is connected to a control piston (91) which forms the valve seat (92,102) with the main piston (93). The main piston (93) is held by a spring (94) against the action of the control magnet (84). The valve seat (92,102) is opened or closed according to the ratio of the magnetic force to the force from the low-pressure valve chamber (90). ADVANTAGE - The assembly gives a simple control for the required gas pressures for the flame cutting according to the nature of the workpiece.