Construction And Operation Principles - SMC Networks IR2000-A Series Operation Manual

３． Construction and Operation Principles
When the knob is rotated, the flapper is pushed through the spring, and a gap is generated
between the nozzle and flapper. The supply pressure flows to the inlet passes through the path
between the nozzle and flapper and acts on the supply diaphragm as nozzle pressure. The force
generated by the diaphragm pushes down the valve, and the supply pressure flows to the outlet.
The discharged air pressure acts on the exhaust diaphragm, and counteracts against the force
generated by the supply diaphragm. The air pressure acts on the nozzle diaphragm at the same
time, and counteracts against the compression force of the adjusting spring to adjust the set
pressure. When the set pressure increases too much, the nozzle diaphragm is pushed up, and a
gap is generated between the flapper and nozzle diaphragm. This happens after the flapper
closes. The balance of the supply diaphragm and exhaust diaphragm is lost when the nozzle back
pressure flows into the atmosphere. The exhaust valve is open after the valve is closed, and
excess pressure on the outlet is released to the air. Due to this pilot mechanism, fine pressure
variations are detected and precise pressure adjustment is possible.
Adjusting spring
②
Flapper
③
⑤
⑥ Supply
diaphragm
Inlet (IN)
⑧
Component parts
No. Description
Bonnet
①
Nozzle diaphragm assembly
②
Seal
③
Seal
④
Diaphragm spacer
⑤
Supply diaphragm
⑥
Exhaust diaphragm assembly
⑦
Valve assembly
⑧
Body
⑨
Grease: lithium grease
knob
①
Nozzle diaphragm
Nozzle
⑦
Exhaust diaphragm
Outlet (OUT)
Valve
⑨
Aluminum, Weather resistant NBR
Aluminum, Weather resistant NBR
Aluminum, stainless steel, HNBR
-8-
IN / OUT side
④
Materials
Aluminum die-cast
HNBR
NBR
Polyacetal
Weather resistant NBR
Aluminum die-cast
④