Air heater

Abstract

A liquid fuel air heater comprises a housing defining a motor housing portion and a grip portion extending from the motor housing portion. An electric motor is positioned in the motor housing portion. A combustion chamber is at least partially positioned within the motor housing portion. A fan is driven by the motor when activated for generating an axial airflow through the combustion chamber. A battery pack containing a plurality of battery cells connected to each other in a series or parallel arrangement is removably coupled to the grip portion of the housing for supplying power to the motor.

1 . A liquid fuel air heater comprising:
 a housing defining a motor housing portion and a grip portion extending from the motor housing portion;   an electric motor positioned in the motor housing portion;   a combustion chamber at least partially positioned within the motor housing portion;
 a fan driven by the motor when activated for generating an axial airflow through the combustion chamber; and 
 a battery pack containing a plurality of battery cells connected to each other in a series or parallel arrangement, the battery pack being removably coupled to the grip portion of the housing for supplying power to the motor. 
   
     
     
         2 . The liquid fuel air heater of  claim 1 , further comprising a liquid fuel container for providing liquid fuel to the combustion chamber. 
     
     
         3 . The liquid fuel air heater of  claim 2 , further comprising a control valve to alternatively permit or prevent the flow of liquid fuel from the liquid fuel container to the combustion chamber. 
     
     
         4 . The liquid fuel air heater of  claim 3 , wherein the control valve is a solenoid actuated valve. 
     
     
         5 . The liquid fuel air heater of  claim 3 , further comprising an ignitor configured to ignite liquid fuel in the combustion chamber. 
     
     
         6 . The liquid fuel air heater of  claim 5 , further comprising an actuator moveable between a first position in which the motor is off and the control valve is closed and a second position, wherein the actuator biased to the first position, and wherein when the actuator is in the second position for a predetermined period of time, the control valve is opened, the ignitor creates sparks to ignite liquid fuel in the combustion chamber, and the motor is activated. 
     
     
         7 . The liquid fuel air heater of  claim 6 , wherein after the control valve is opened, if a temperature of the combustion chamber is below a threshold temperature for a second predetermined period of time, the control valve is closed. 
     
     
         8 . The liquid fuel air heater of  claim 3 , wherein after the control valve is opened, if a temperature of the combustion chamber is below a threshold temperature for a predetermined period of time, the control valve is closed. 
     
     
         9 . The liquid fuel air heater of  claim 8 , wherein after the control valve is opened, if a temperature of the combustion chamber is greater than or equal to the threshold temperature for a predetermined period of time, the control valve is kept open. 
     
     
         10 . The liquid fuel air heater of  claim 9 , further comprising a thermocouple configured to produce a voltage that is proportional to the temperature of the combustion chamber and provided as an input to a controller, wherein after the control valve is opened if the temperature of the combustion chamber is greater than or equal to the threshold temperature for the predetermined period of time, the controller keeps the control valve open in response to receiving the input. 
     
     
         11 . The liquid fuel air heater of  claim 3 , further comprising a heating blanket in thermal contact with and at least partially surrounding the liquid fuel container, wherein the heating blanket, when activated, increases a temperature of the liquid fuel container. 
     
     
         12 . The liquid fuel air heater of  claim 11 , wherein the heating blanket is activated when the temperature of the liquid fuel container falls below a threshold temperature. 
     
     
         13 . A liquid fuel air heater comprising:
 a housing defining a motor housing portion;   an electric motor positioned in the motor housing portion;   a combustion chamber at least partially positioned within the motor housing portion;   a fan driven by the motor when activated for generating an axial airflow through the combustion chamber;   a liquid fuel container at least partially positioned in the housing for providing liquid fuel to the combustion chamber; and   a heating blanket in thermal contact with and at least partially surrounding the liquid fuel container,   wherein the heating blanket, when activated, increases the temperature of the liquid fuel container.   
     
     
         14 . The liquid fuel air heater of  claim 13 , wherein the heating blanket is activated when a temperature of the liquid fuel container falls below a threshold temperature. 
     
     
         15 . The liquid fuel air heater of  claim 13 , wherein the housing defines a grip portion extending from the motor housing portion. 
     
     
         16 . The liquid fuel air heater of  claim 15 , further comprising a battery pack containing a plurality of battery cells connected to each other in a series or parallel arrangement, wherein the battery pack is removably coupled to the grip portion of the housing for supplying power to the motor. 
     
     
         17 . The liquid fuel air heater of  claim 13 , further comprising an ignitor configured to ignite liquid fuel in the combustion chamber and a control valve to alternatively permit or prevent the flow of liquid fuel from the liquid fuel container to the combustion chamber. 
     
     
         18 . The liquid fuel air heater of  claim 17 , further comprising an actuator moveable between a first position in which the motor is off and the control valve is closed and a second position, the actuator biased to the first position, and wherein when the actuator is in the second position for a first predetermined period of time, the control valve is opened, the ignitor creates sparks to ignite liquid fuel in the combustion chamber, and the motor is activated. 
     
     
         19 . The liquid fuel air heater of  claim 18 , wherein after the control valve is opened, if a temperature of the combustion chamber is below a threshold temperature for a second predetermined period of time, the control valve is closed, and if the temperature of the combustion chamber is greater than or equal to the threshold temperature for the second predetermined period of time, the control valve is kept open. 
     
     
         20 . The liquid fuel air heater of  claim 19 , further comprising a thermocouple configured to produce a voltage that is proportional to the temperature of the combustion chamber and provided as an input to a controller, wherein after the control valve is opened if the temperature of the combustion chamber is greater than or equal to the threshold temperature for the predetermined period of time, the controller keeps the control valve open in response to receiving the input. 
     
     
         21 . The liquid fuel air heater of  claim 17 , wherein after the control valve is opened, if a temperature of the combustion chamber is below a threshold temperature for a predetermined period of time, the control valve is closed, and if the temperature of the combustion chamber is greater than or equal to the threshold temperature for the predetermined period of time, the control valve is kept open. 
     
     
         22 - 28 . (canceled)