System for dynamic airflow control in a paint booth using multiple air supply plenums

A system for handling airflow in a paint booth comprising:

• a paint booth adapted to receive airflow from two or more plenum outlets located above the paint booth;
• a primary plenum supplied with higher pressure air from an air source and having a primary plenum outlet;
• a secondary plenum within the primary plenum, supplied with air by the primary plenum and having a secondary plenum outlet adjacent to a portion of said primary plenum outlet and generally above a paint spray applicator within said paint booth, wherein relatively low density filter media extends between the secondary plenum outlet and the balance of the paint booth, and wherein the secondary plenum outlet has one or more airflow restrictors directly above the paint spray applicator;
• a variable density filter media extending across the primary plenum outlet, with relatively higher density media being installed at a plurality of locations at the primary plenum outlet, thereby creating lower velocity airflow beneath said locations within the paint booth, and with relatively lower density media being installed at a plurality of locations at the primary plenum outlet, thereby creating high velocity airflow beneath said locations;
• an airflow velocity detector within the paint booth and near said paint spray applicator, adapted to transmit a signal corresponding to air velocity below the secondary plenum outlet;
• and
• an adjustable damper for controlling airflow from the primary plenum to the secondary plenum based at least in part on the value of said air velocity signal.

A method of controlling airflow velocity in a paint booth comprising:

• supplying air under pressure to a primary plenum having a primary plenum outlet located above a paint booth;
• supplying air from the primary plenum to a secondary plenum that is enclosed within the primary plenum, with said secondary plenum having a secondary plenum outlet located generally above a paint spray applicator and above a workpiece within said paint booth;
• using an airflow velocity detector, installed in the airflow between the secondary plenum outlet and said workpiece, to generate a signal corresponding to air velocity beneath the secondary plenum outlet;
• and
• dynamically controlling the air supplied to the secondary plenum in real time by adjusting a damper at a secondary plenum inlet based at least in part on the value of said air velocity signal.