High velocity, hot air dryer and extractor

A hot air dryer comprising, in combination:

• a dryer head including an elongated housing member having a tubular sidewall defining a plenum chamber, the tubular sidewall being intersected by an airflow discharge port;
• an elongated air delivery tube having an inlet port for receiving high velocity airflow and having a tubular sidewall disposed in the plenum chamber of the dryer head, the tubular sidewall having an inner airflow passage connecting the inlet port in airflow communication with the plenum chamber;
• an elongated heating element disposed within the inner airflow passage of the air delivery tube;
• an end block coupled to,the housing member, the end block having a body portion intersected by an axial bore, a counterbore and a radial inlet bore communicating with the counterbore;
• the heating element having an end portion projecting through the axial bore and counterbore;
• and,
• the air delivery tube having an end portion disposed in the counterbore with its inner airflow passage coupled in airflow communication with the radial inlet bore.

A hot air dryer for use in combination with a printing press of the type having conveyor apparatus for transporting a processed substrate along a sheet travel path comprising, in combination:

• first and second elongated dryer heads adapted for side-by-side installation in a position facing the freshly processed side of a substrate as it moves through a dryer exposure zone along the sheet travel path, each dryer head having a housing member defining an air distribution manifold chamber, each air distribution manifold housing member including an inlet port for receiving high velocity air and having a discharge port oriented for directing pressurized air toward the sheet travel path, the dryer heads being separated from each other by a longitudinal air gap;
• first and second elongated heating elements disposed within the air distribution manifold chambers of the first and second dryer heads, respectively, for heat exchange contact with high velocity air directed through the respective air distribution manifolds;
• and,
• an extractor coupled to the dryer heads, the extractor including a housing defining an extractor manifold chamber coupled in air flow communication with the longitudinal air gap, and having an extractor port coupled in air flow communication with the extractor manifold chamber for exhausting moisture laden air, high velocity hot air and volatiles from the dryer exposure zone.

A hot air dryer for use in combination with a printing press of the type having conveyor apparatus for transporting a processed substrate along a sheet travel path comprising, in combination:

• first and second elongated dryer heads adapted for side-by-side installation in a position facing the freshly processed side of a substrate as it moves through a dryer exposure zone along the sheet travel path, each dryer head having a housing member defining an air distribution manifold chamber, each air distribution manifold housing member including an inlet port for receiving high velocity air and having a discharge port oriented for directing pressurized air toward the sheet travel path, the driver heads being separated from each other by a longitudinal air gap;
• first and second elongated heating elements disposed within the air distribution manifold chambers of the first and second dryer heads, respectively, for heat exchange contact with high velocity air directed through the respective air distribution manifolds;
• an extractor coupled to the dryer heads, the extractor including a housing defining an extractor manifold chamber coupled in air flow communication with the longitudinal air gap, and having a discharge port coupled in air flow communication with the extractor manifold chamber for exhausting moisture laden air from the dryer exposure zone;
• first and second end blocks coupled to the housing member of each dryer head, each end block having a body portion intersected by an axial bore, a counterbore and a radial inlet bore communicating with the counterbore;
• each heating element having an end portion projecting through the axial bore and counterbore;
• and,
• each air delivery tube having an end portion disposed in the counterbore with its inner airflow passage coupled in airflow communication with the radial inlet bore.

A dryer for use in combination with a printing press of the type having conveyor apparatus for transporting a freshly processed substrate along a travel path comprising, in combination:

• a first dryer head having a housing defining an air distribution manifold chamber, the dryer head housing having an inlet port for admitting pressurized air into the manifold chamber and having a discharge port oriented for directing pressurized air from the manifold chamber into a dryer exposure zone;
• a second dryer head having a housing defining a second air distribution manifold chamber, the second dryer head housing having an inlet port for admitting pressurized air into the second manifold chamber and having a discharge port oriented for directing pressurized air from the second manifold chamber into the dryer exposure zone;
• the first and second dryer heads being adapted for side-by-side installation on the press in a position facing the freshly processed side of a substrate as it moves through the dryer exposure zone, the dryer heads being separated from each other by a longitudinal air gap;
• and,
• an extractor head coupled to the dryer heads, the extractor head including a housing defining an extractor manifold chamber coupled in air flow communication with the longitudinal air gap, and having discharge port means coupled in air flow communication with the extractor manifold chamber for exhausting air from the exposure zone.

A method for drying a freshly printed sheet in a printing press comprising the steps:

• directing high velocity air through an air delivery tube which is disposed within the plenum chamber of an air distribution manifold;
• heating high velocity air flowing through the air delivery tube by heat transfer contact with an elongated heating element disposed within the air delivery tube;
• pressurizing the air distribution plenum chamber with the heated air;
• and,
• discharging the pressurized, heated air from the plenum chamber onto the freshly printed sheet.