Burner construction for air heaters using an ultrasonic atomizer

Abstract

A burner for air heaters comprises a first wall structure defining an ignition chamber with an ultrasonic atomizer discharging into the ignition chamber and with means for delivering primary air into the ignition chamber for ignition by suitable ignition device to form an igniting gas mixture. The construction includes a second wall arrangement which is adjacent the ignition chamber and which defines a primary combustion chamber which has a passage for the ignited gas mixture from the ignition chamber and also for secondary air so as to complete the combustion in the main combustion chamber. The main combustion chamber in turn is connected downstream and into an exhaust diffuser in which the completely burnt gases are delivered to a place of use for heating an area such as a space in a motor vehicle. In one construction, the combustion chamber is defined within a perforated tube which has a perforated bottom or rear wall facing an ignition chamber which is defined with an outer tube which is also perforated to provide for the inflow of the primary air. The ignition device is mounted in the outer tube adjacent the atomizer so as to ignite the fuel with the primary air and direct this ignited mixture into perforations of the main combustion chamber for continued burning therein. In another embodiment the primary chamber is defined by a perforated wall which defines an area within the outer perforated housing which comprises the ignition chamber having the atomizer in an igniting element. This ignition chamber communicates through perforations in the surrounding wall with an inlet for the primary air and one or more inlets for the secondary air in the remaining space within the outer housing which defines the main combustion chamber.