Abstract: A dual fuel boiler has fuel delivery apparatus coupled to its burner section through a pressure regulator and operative to deliver to the burner section, from sources thereof, a selectively variable one of (1) a first fuel at a pressure greater than the pressure regulation setting of the pressure regulator, and (2) a second fuel at a pressure less than the pressure regulation setting, the second fuel having a Wobbe index greater that that of the first fuel. The first fuel is flowed to the burner section via a branch supply line in which first and second electromechanical two position, two-way, two position valves are installed in series in opposite normal flow orientations to thereby prevent backflow of the second fuel into the source of the first fuel.

Abstract: The present invention relates to apparatus and methods for winding filament to create a structure. In one embodiment, the invention includes the application of filament to a rotating mandrel to create a desired shape. The invention includes the filament winding of both simple and complex shapes.

Abstract: A single piece co-cured composite wing is disclosed. The wing has a flying surface and structural members. In one embodiment the structural members may be a plurality of spars. The spars may have various shapes to increase the buckling strength. The spars may be wave shaped, such as a sinusoidal shape. The flying surface and the structural members are co-cured in order to form a single piece, integral wing structure. A process for manufacturing a single piece co-cured wing is also disclosed. The process may include laying out composite sheets for the flying surface of the wing. Then, the composite material of the spars is arranged around a plurality of pressurizable forms. Finally, the composite material is cured in a clamshell frame. A single piece co-cured composite structure is also disclosed that includes an outer skin, and inner skin, a frame, and a stringer.

Abstract: A method for manufacturing a composite structure is disclosed herein. The process uses a frame and selectively pressurizable forms. The forms define the interior members of the composite structure and frames define the exterior surface of the composite structure. Composite material is wrapped around the forms and the forms and composite material are placed in the frame. Selective forms are then pressurized and the composite material is co-cured together. A single piece co-cured fuselage incorporating a plurality of stiffeners is also disclosed in the application. The stiffeners are co-cured to the fuselage and may be in various patterns. The patterns may include an iso-grid pattern, and ortho-grid pattern, and a hoop-grid pattern.

Abstract: An apparatus used to form a three-dimensional composite structure is disclosed having an initially rigid heat-softenable layer of ABS plastic wherein uncured portions of the composite structure are first assembled between the layer of ABS plastic and a hard mold surface. Prior to curing of the composite structure, pressure and heat are applied to the ABS layer to soften the layer and thereafter compact the uncured portions of the structure against the hard mold surface. The ability to pre-shape the ABS layer allows stiffening beams to be incorporated into the structure so as to yield a lightweight, strong composite structure that can be used as a pressure vessel in an aerospace vehicle.

Abstract: A process is disclosed for forming a thermoplastic structure on the exterior surface of the heated mold form. A mold is heated to approximately two times the melting temperature of a thermoplastic material and particulate thermoplastic material then sprinkled onto the exterior surface of the heated mold. An adhesively bondable material may then be added to the semi-molten thermoplastic material structure. The mold is then cooled and the resulting thermoplastic structure removed.An apparatus for practicing the above process comprising a mold form, heating system, and particulate thermoplastic material dispensing system is also disclosed.

Abstract: A process is disclosed for forming a thermoplastic structure on the exterior surface of the heated mold form. A mold is heated to approximately two times the melting temperature of a thermoplastic material and particulate thermoplastic material then sprinkled onto the exterior surface of the heated mold. An adhesively bondable material may then be added to the semi-molten thermoplastic material structure. The mold is then cooled and the resulting thermoplastic structure removed.An apparatus for practicing the above process comprising a mold form, heating system, and particulate thermoplastic material dispensing system is also disclosed.

Abstract: A heat exchanger or boiler has a bypass between the inlet and the outlet. The outlet includes a chamber having a partition with a thermostatically controlled valve, which controls flow of heating medium from the heat exchanger to the outlet connection. The thermostat maintains the temperature at the chamber. The bypass is from an inlet chamber to the space beyond the thermostat. The thermostatic valve, itself, is of a typical known construction consisting of a valve member actuated relative to a port in a plate by means of a thermostatic element axially positioned relative to the valve member. The plate forms part of a partition formed in a header member which forms a chamber at the outlet of the heat exchanger from which the heating medium flows through the thermostatic valve, to the outlet conduit. The bypass is controlled by a plate partially obstructing a passageway and it may be flexible to respond to flow of medium to have a throttling effect.

Abstract: A five-way valve embodying a cylindrical body with valve seats and cooperating valve discs operable by a stem and having associated inlet and outlet ports. The stem is actuatable by pistons in the cylindrical body. The pistons are driven by pressure under the control of three-way valves. The valve structure is adaptable for use in a swimming pool heating system having a primary pool heater and also a solar heater. The water is circulated by a pump pumping through a filter. The three-way valves are controlled in response to a thermostat responsive to temperature at the solar heater. The three-way valves respond to water pressure differential as between the upstream and downstream sides of the pump in the system.