Pressure dependent dust control filter compressed air reversed flushing control system

A compressed fluid flushing system, which comprises:

• a compressed fluid reservoir;
• a fluid compressor having an outlet connected to supply compressed fluid to said reservoir;
• means for regulating the volume rate of compressed fluid produced by the compressor for discharge at said compressor outlet;
• a plurality of flushing valve connected to receive compressed fluid from said reservoir, each of said flushing valves including a pilot chamber and main chamber separated from said pilot chamber by diaphragm valve means for releasing pressure in said main chamber in response to a drop in pressure in said pilot chamber;
• a control valve adapted to sense fluid pressure in said reservoir and open at said selected pressure;
• and a sequencing valve having a first inlet connected to receive pressure from said control valve, and a plurality of second inlets connected to receive pressure from said pilot chambers, said sequencing valve including piston means operable in response to pressure received at said first inlet for releasing pressure at a selected one of said second inlets thereby to operate a selected one of said flushing valves, said sequencing valve including means for indexing said piston to release pressure at a second selected one of said inlets.

The system as claimed in claim 18, wherein said sequencing valve includes:

• a valve body having a cylindrical bore;
• said piston means including a piston slidingly mounted in said bore and dividing said bore into a first chamber and a second chamber;
• said first inlet being connected to said first chamber;
• an outlet for discharging air from said first chamber;
• said plurality of second inlets being connected to said second chamber;
• a normally closed valve in each of said second inlets;
• means for venting said second chamber;
• said piston means including operator means on said piston for opening one of said valves in said second inlets;
• means for biasing said piston toward said first chamber;
• and said indexing means includes means for rotating said piston in response to axial movement of said piston within said bore, whereby said operator means sequentially opens said valves in said second inlets in response to fluid pressure received at said first inlet.