Self-cleaning air filter

A self-cleaning air filter apparatus connected to a compressed air source comprising:

• a filter casing defining an interior therein, the filter casing includes an air inlet at a first end thereof and an air outlet at a second end thereof opposite the first end, the filter casing also includes a sidewall having an opening therein,
• a filter element disposed within the filter casing and having an interior and an exterior thereof, whereby during a filtering cycle a negative pressure differential between the filter element interior and the filter element exterior draws airflow inward through the filter element during a filtering cycle and during a self-cleaning cycle a positive pressure differential between the filter element interior and the filter element exterior forces airflow outward through the filter element,
• a valve mounted to the filter casing and connected to the compressed air source for automatically and periodically releasing a pulse of compressed air into the filter element whereby dust is dislodged from the filter element exterior into the filter casing, the valve includes a nozzle extending into the outlet port for directing the compressed air pulse laterally through the filter element interior toward the first end of the filter casing and radially outward through the filter element;
• and
• a vent mounted to the filter casing between the first end of the filter casing and the second end of the filter casing for venting the pulse of compressed air from the filter casing to maintain a positive pressure differential between the filter element interior and the filter element exterior during the cleaning cycle, the vent includes a pliable diaphragm shiftably seated over the sidewall opening between an open position spaced from the sidewall opening and a closed position enclosing the sidewall opening and a spring biasing the diaphragm in to the closed position.