Abstract: A system and method for inductive heating, in which a power source provides current pulses with high-frequency harmonics to a heater coil, the coil generating a magnetic flux for inductive heating of an article. The high-frequency harmonics enhance a relative proportion of inductive heating, compared to resistive heating of the heater coil. Providing these high-frequency harmonics, occurring above the border frequency of the heating system, enables the system to deliver an increased proportion of inductive heating, compared to resistive heating, without requiring an increase in the Root Means Square (RMS) current in the coil. Providing better coupling between the coil and the core, such as by embedding the coil wholly or at least partially in the core, and providing a magnetic yoke to close the loop with the core, can provide a significantly decreased border frequency.

Abstract: A thermoplastic article is produced by welding or injection molding. The mechanical performance of the article is optimized by a method employing a plurality of test samples also produced by welding or injection molding. For welding, each test sample comprises two thermoplastic workpieces welded at an interface having a preselected shape. The test samples are prepared using different welding conditions and tested. The results are used to select injection molding conditions for the first and second workpieces. For injection molding, each test sample is prepared with a knit line having a preselected shape. The test samples are injection molded using different conditions and tested. The results are used to select welding conditions for the first and second workpieces. The test samples are much easier to prepare than samples that have to be machined from full-scale articles made under the requisite variety of experimental conditions heretofore required for process optimization.

Abstract: A system and method for inductive heating, in which a power source provides current pulses with high-frequency harmonics to a heater coil, the coil generating a magnetic flux for inductive heating of an article. The high-frequency harmonics enhance a relative proportion of inductive heating, compared to resistive heating of the heater coil. Providing these high-frequency harmonics, occurring above the border frequency of the heating system, enables the system to deliver an increased proportion of inductive heating, compared to resistive heating, without requiring an increase in the Root Means Square (RMS) current in the coil. Providing better coupling between the coil and the core, such as by embedding the coil wholly or at least partially in the core, and providing a magnetic yoke to close the loop with the core, can provide a significantly decreased border frequency.

Abstract: A frictionally welded, filled thermoplastic article is strengthened by restricting lateral flow of molten material out of the gap between the workpieces, so that a molten pool of substantial depth is maintained from the beginning of melting to the onset of solidification. The restriction to lateral flow of material is provided by dams (projections) of essentially rectangular cross-section at each lateral edge of one of the workpieces, while the other workpiece has a substantially flat mating surface.

Abstract: A co-injection molded air intake manifold shell comprises an inner and outer skin layer separated by a sound absorbing or sound insulation core. Each skin layer is composed of a polyamide resin which, optionally, contains glass fiber reinforcement and high specific gravity fillers such as barium sulfate or tungsten. The sound insulating core is composed of a high density material having a foam structure, such as a polyamide resin. Skin layers are provided with a plurality of pockets to permit distribution of localized lumped masses at predetermined locations tailored to increase noise transmission losses. A single layer air intake manifold shell having non-uniform thickness is also provided. The thickness of the single layer air intake manifold shell is larger over preselected noise sources of larger amplitude to maximize noise attenuation for a nominal air intake manifold shell thickness.

Abstract: A first workpiece having a first mating surface and a second workpiece having a second mating surface are joined by an ultrasonic welding method to form a joined article. Each of the workpieces is composed of a thermoplastic material. Joining is accomplished by a method comprising the steps of: (i) placing an auxiliary energy director in contact with the first mating surface; (ii) bringing the second mating surface into close proximity with the first mating surface and into contact with the auxiliary energy director; (iii) imposing a compressive force urging the first and second mating surfaces into contact; (iv) activating a source that applies ultrasonic vibration to one of the workpieces for a time sufficient to cause melting of at least a portion of each of the first and second workpieces; (v) discontinuing the application of ultrasonic vibration; and (vi) cooling the workpieces to allow the melted portions to solidify, thereby forming the joined article.

Abstract: A frictionally welded, filled thermoplastic article is strengthened by restricting lateral flow of molten material out of the gap between the workpieces, so that a molten pool of substantial depth is maintained from the beginning of melting to the onset of solidification. The restriction to lateral flow of material is provided by dams (projections) of essentially rectangular cross-section at each lateral edge of one of the workpieces, while the other workpiece has a substantially flat mating surface.

Abstract: A co-injection molded air intake manifold shell comprises an inner and outer skin layer separated by a sound absorbing or sound insulation core. Each skin layer is composed of a polyamide resin which, optionally, contains glass fiber reinforcement and high specific gravity fillers such as barium sulfate or tungsten. The sound insulating core is composed of a high density material having a foam structure, such as a polyamide resin. Skin layers are provided with a plurality of pockets to permit distribution of localized lumped masses at predetermined locations tailored to increase noise transmission losses. A single layer air intake manifold shell having non-uniform thickness is also provided. The thickness of the single layer air intake manifold shell is larger over preselected noise sources of larger amplitude to maximize noise attenuation for a nominal air intake manifold shell thickness.

Abstract: A frictionally welded, filled thermoplastic article is strengthened by restricting lateral flow of molten material out of the gap between the workpieces, so that a molten pool of substantial depth is maintained from the beginning of melting to the onset of solidification. The restriction to lateral flow of material is provided by dams (projections) of essentially rectangular cross-section at each lateral edge of one of the workpieces, while the other workpiece has a substantially flat mating surface.

Abstract: Two polygon shaped articles having walls of different thicknesses are mated and welded together. Specimens cut from this composite part are used to evaluate the performance of welded joints with the influence of design, processing conditions such as welding, molding, and the like, and material composition. The evaluation advantageously provides an accurate predictor for linear vibration, orbital vibration, hot plate, hot gas, hot gas extrusion and infrared welding at a variety of bead thicknesses.