Abstract: A heat exchanger is characterized by having two or more fluid flow circuits, each formed by multiple small cross-section “micro-tubes” contained within a surrounding metal structure, or “metal matrix.” Its function is to efficiently transfer heat from one fluid to another in a highly compact assembly. Most any metal or metal alloy can be considered for the micro-tubes. The micro-tubes, while typically arranged in alternating layers of alternating flow circuits, may be organized in any number of arrangements including co-linear and at cross angles to provide for co-flow, counter flow and cross flow. The metal matrix, is provided in one embodiment by a metal or metal alloy powder consolidated in a hot isostatic pressing (HIP) process. This process also joins the tubes together and to the matrix itself, producing a monolithic structure.

Abstract: A heat exchanger is characterized by having two or more fluid flow circuits, each formed by multiple small cross-section “micro-tubes” contained within a surrounding metal structure, or “metal matrix.” Its function is to efficiently transfer heat from one fluid to another in a highly compact assembly. Most any metal or metal alloy can be considered for the micro-tubes. The micro-tubes, while typically arranged in alternating layers of alternating flow circuits, may be organized in any number of arrangements including co-linear and at cross angles to provide for co-flow, counter flow and cross flow. The metal matrix, is provided in one embodiment by a metal or metal alloy powder consolidated in a hot isostatic pressing (HIP) process. This process also joins the tubes together and to the matrix itself, producing a monolithic structure.

Abstract: A heat exchanger is characterized by having two or more fluid flow circuits, each formed by multiple small cross-section “micro-tubes” contained within a surrounding metal structure, or “metal matrix.” Its function is to efficiently transfer heat from one fluid to another in a highly compact assembly. Most any metal or metal alloy can be considered for the micro-tubes. The micro-tubes, while typically arranged in alternating layers of alternating flow circuits, may be organized in any number of arrangements including co-linear and at cross angles to provide for co-flow, counter flow and cross flow. The metal matrix, is provided in one embodiment by a metal or metal alloy powder consolidated in a hot isostatic pressing (HIP) process. This process also joins the tubes together and to the matrix itself, producing a monolithic structure.

Abstract: Improved fuel cell stacks constructed from a plurality of cells, each comprising a series of interrelated mono and bipolar collector plates (BSPs), which in turn are built up by lamination of a core of related non-conductiveplastic orceramic platelets sandwiched between conductive microscreen platelets of metal or conductive ceramic or plastic, with an electrode membrane (EMA) between adjacent BSPs. The platelets, both metal and plastic of the composite BSPs, are produced from sheet material with through and depth features formed by etching, pressing, stamping, casting, embossing and the like. Adjacent plates, each with correspondingly relieved features form serpentine channels within the resultant monolithic platelet/cell stack for integrated fluid and thermal management. The plastic platelets are particularly useful for PEM fuel cells employing H.sub.2 and Air/O.sub.2 as fuel. The platelets are easily made by printing (embossing) processes, and dies made by photolithographic etching for rapid redesign.

Abstract: Platelet assemblies are formed from bondable platelets, such as diffusion-bondable, brazable, or adhesive-bondable platelets, with void regions in the platelets to form channels or open spaces in the finished platelet assembly. To improve the response of the platelet assembly to pressure bonding as well as to post-bonding fabrication processes such as forming, machining and welding, the void regions are filled with a sacrificial material which transmits the load of the applied pressure in the same manner as the remainder of the platelet, and yet which is removable from the finished platelet assembly by either thermal or chemical liquefaction after all potentially damaging fabrication procedures have been performed on the platelet assembly.

Abstract: A connecting rod having a multiplicity of internal cavities and external pockets that allow optimization of the rod structural properties while minimizing weight. The rod is fabricated as a multiple piece assembly, utilizing wrought materials and metallurgical joining techniques.

Abstract: Single sideband modulation system. A first single sideband of radio frequency is generated with first audio modulation on the lower side of an assigned frequency, the first single sideband bandwidth being equal to the highest frequency of said first audio modulation. A second single sideband of radio frequency is generated with second audio modulation on the upper side of the assigned frequency, the second single sideband bandwidth being equal to the highest frequency of said second audio modulation. A first stereo channel is modulated on the lower sideband frequency. A second stereo channel is modulated on the upper sideband frequency. The stereo channels are combined whereby a receiver tuned to the assigned non-transmitted carrier frequency will receive both stereo channels.