Abstract: A stove for burning fuel in which secondary air is introduced and mixed with the products of combustion in a firebox with primary air, the secondary air being kept from the firebox by a gravity-induced downward movement owing to the greater density of the secondary air-combustion products mixture as compared with the products of combustion per se.

Abstract: A combustor including a combustion chamber having two paths for removing combustion exhaust gases, a valve in one path, and means to provide, when the valve is in a closed position, pressure at a downstream side of the valve higher than the pressure inside the combustion chamber to prevent leakage of combustion gases from the combustion chamber through the valve.

Abstract: Apparatus supporting a catalytic converter for a burner comprising a support including an opening for passage of exhaust gases therethrough, a catalytic converter mounted on the support for movement into and out of an operating position adjacent to the opening to receive the exhaust gases, and means extending from the support for causing the catalytic converter to be moved into and out of the operating position.

Abstract: Apparatus for supporting a catalytic converter for a burner including a housing having an opening for directing the exhaust gases to a catalyst region and a by-pass opening permitting the exhaust gases to by-pass the catalyst region, a baffle positioned over the catalyst region and having a groove formed in it and a tab extending from one end and adjacent to the groove, a closure movably mounted to open and close the by-pass opening, and a control rod slidably and pivotally mounted within the groove and having one end connected to the closure to open and close the by-pass opening by pivoting of the rod, the rod being lockably engageable by the tab by longitudinal displacement of the rod when in a pivotal position corresponding to closing of the by-pass opening, and having handle means extending from the other end for permitting pivoting and longitudinal displacement of the rod.

Abstract: This stove is divided by a partition into a lower, combustion chamber, and an upper chamber which communicates directly with an exhaust opening in the stove. A catalytic converter is removably mounted in an opening in the partition. A by-pass damper, which is connected to the stove door, is normally held closed over a by-pass opening in the wall of the lower chamber, when the door to the stove is closed, whereby all combustion gases from the lower chamber must pass upwardly through the converter and the secondary chamber to the exhaust opening. When the stove door is opened, the by-pass damper tilts by gravity into an open position so that combustion gases from the lower chamber pass directly to the exhaust opening rather through the upper chamber, and rather than being accidentally discharged out of the open door. The converter causes all by-products of combustion to be subjected to a secondary combustion in the converter before passing to the exhaust opening.

Abstract: A wood burning stove having a catalytic converter for achieving greatly increased combustion efficiency, said stove having damper means for insuring that all combustion gases from the primary combustion chamber pass through said converter before reaching the stove's exhaust duct when the damper is in one position, and manual control means for moving the damper to a second position wherein the combustion gases bypass said converter and pass directly to said exhaust duct, it being necessary to move said damper to its second position before the door of said stove can be opened. Said damper has a controlled leakage factor whereby if the converter becomes clogged when the damper is in its first position, combustion gases will be permitted to pass to said exhaust duct. In one operational mode, the stove may be used to burn coal.

Abstract: A wood burning stove having a primary combustion chamber and a secondary chamber having a catalytic converter therein is disclosed. Primary air is introduced to said primary chamber and secondary air is introduced to said secondary chamber utilizing completely separate and independent control means, with the draft means for said primary and secondary air both being located below the fuel (wood) support level. Means are provided for preheating both the secondary air and the catalytic converter.

Abstract: A modular heat exchange element, adapted to be positioned in fixed relation to one or more other of such modules, may be produced as a monolithic, honeycombed body having a plurality of flow paths therethrough for at least two fluids. The body is provided with a plurality of cells extending from one face end of the body to the other face end thereof and arranged in columns of cells separated by fluid barrier wall surfaces. At least selected columns of cells are closed on both face ends of the body, with inlets and outlets for the selected cells provided by removing portions of the boundary surfaces and fluid barrier walls of the columns of cells near face ends of the body. A first fluid may enter selected columns of cells through the inlets and exit from the outlets near the other end thereof. A second fluid passes through the other selected columns of cells.

Abstract: There has been provided an armored beaded piping system, having a boot of corrosive resistant material adapted to shield the forward end of the armor from corrosives and to provide a protective end covering, which is grasped by a pipe coupler such that separation of the pipe system from the coupler is prevented upon inner pipe failure.

Abstract: There has been provided a coupler for joining lengths of concentric pipe. A sleeve member receives the pipes in spaced relation therein, with an end of the concentric inner pipe forward of the end of the outer pipe. A forward annular flange portion of said sleeve member is concentric with the pipes and extends radially inward as well as outward of the sleeve member. A rearward face of said flange portion faces the forward end of the outer pipe and is spaced away therefrom by a selected length of said tail portion forming an annular groove bounded by the outer pipe end and inner wall of said tail portion of the selected length and the rear face of the flanged portion. A compressible O-ring type elastomer seal is disposed in the annular groove and extends radially inward of said outer pipe. A gasket is concentrically sleeved between said O-ring seal and outer wall of the inner pipe. In compression, the O-ring seal and gasket form a circumferential seal about the inner pipe.