Portable steam and heat generator for pest control

Abstract

The present invention describes numerous improvements in steam generating apparatus for pest control. In one aspect, an improved cart arrangement for such an apparatus is described. Other aspects include improved valves, nozzles and other improvements to increase the efficiency of the steam generating apparatus.

1 . An apparatus for generating at least one of steam, hot water and hot water vapor along with air heated by a burner for application to unwanted vegetation, the apparatus comprising a wheeled cart supporting a water container, a control module, a holder for an applicator wand and a fuel container, the applicator wand comprising a holding means and an applicator head coupled to the holding means, the applicator head comprising a housing, an inlet and an outlet to define a cavity to accept a flash boiler adjacent the outlet, the flash boiler comprising a steam generator and a burner for heating the steam generator, a first elongate hose connecting the water container to a first control located on the applicator wand, the first control controlling and supplying a flow of water to the steam generator, and a second elongate hose connecting the fuel container to a second control located on the applicator wand, the second control controlling and supplying a flow of fuel to the burner, both the first and second controls being controlled by a single switch, such that when said switch is activated, fuel and water are supplied essentially simultaneously to said flash boiler and a blast of heated air and at least one of steam, superheated steam, hot water and hot water vapor is urged from the outlet to the unwanted vegetation, the control module of the wheeled cart including a water pump to supply water to the applicator wand from the water tank, a source of energy for the water pump and control and feedback circuitry and displays to allow an operator to monitor the operating parameters of the apparatus. 
     
     
         2 . A flow control and flush valve for a steam generating apparatus for weed control, which allows for a simple means of controlling the volume of water flowing through the system, the flow control valve comprising a first fixed elliptical orifice and a second rotating elliptical orifice, the center of rotation of the second elliptical orifice being located adjacent one end of the orifice, the rotation of the rotating orifice varying the overlapping area between the fixed orifice and the rotating orifice to allow for control of the volume of water flowing through the overlapping orifices. 
     
     
         3 . A trigger control valve having a bypass channel such that a small flow of fluid passes through the valve when the valve is in the closed position, the trigger control valve being provided with an inlet and outlet and a spring biased poppet, which seals the outlet when the valve is in the closed position, the sealing surface of the valve against which the poppet rests being provided with a channel to allow for a low flow of water in the closed position. 
     
     
         4 . A steam nozzle for a steam generating apparatus for weed control, the steam nozzle aiding in diffusing the steam and accelerating the airflow through the steam generating apparatus, the steam nozzle comprising an inlet and a plurality of outlets to provide for the diffusion of the steam from the steam generating apparatus. 
     
     
         5 . The steam nozzle according to  claim 4  wherein the steam nozzle is centrally mounted within the outlet of the steam generating apparatus by a plurality of spacers or fins located between the exterior of the steam nozzle and an interior wall of a steam head of the steam generating apparatus. 
     
     
         6 . The steam generating apparatus according to  claim 1  wherein the steam generating apparatus is provided with an air blower to increase the volume of air flowing through the steam generating apparatus to increase the combustion of the fuel used to heat the flash boiler, as well as to increase the output of steam and hot air from the steam generating apparatus. 
     
     
         7 . The steam generating apparatus according to  claim 1  wherein the steam head containing the steam generating apparatus is provided with an outlet having an elliptical or oval shape to concentrate the steam and hot air to the target area.