Abstract: A dielectric heating section for a blow molding machine is provided. Within the heating section a plurality of heating stations are defined by electrode pairs. At least one electrode of each pair is made recontourable to achieve the desired temperature profile within the wall section of a thermoplastic preform suspended therebetween. The preforms are rotated while supported within the alternating electric field created between the electrodes when the electrodes are energized by a radio frequency signal generator. The preforms are moved from station-to-station to achieve high rate controlled heating of each preform.

Abstract: This relates to the heating of polyethylene terephthalate by way of RF energy. It has been found that if polyethylene terephthalate articles are passed through a radio frequency energy field, the molecules thereof will become excited and rapid heating will result. This heating is particularly useful in the heating of preforms prior to the blow molding thereof and by varying the configuration and relationship of electrodes, controlled heating of the preforms may be effected with it being possible to have a controlled temperature differential along the length of the preform or other article so heated.

Abstract: The wrapped insulation on the straight parallel sections of coils for larger rotary electric machines is treated under heat and pressure in a preferably double-sided coil press in which pressure is applied first to the center of the heated sections then also to the outer parts thereof to enable excess resin impregnating the insulation to flow away from the center parts and achieve a more uniformly and accurately dimensioned coil.

Abstract: This relates to the heating of polyethylene terephthalate by way of RF energy. It has been found that if polyethylene terephthalate articles are passed through a radio frequency energy field, the molecules thereof will become excited and rapid heating will result. This heating is particularly useful in the heating of preforms prior to the blow molding thereof and by varying the configuration and relationship of electrodes, controlled heating of the preforms may be effected with it being possible to have a controlled temperature differential along the length of the preform or other article so heated.

Abstract: An apparatus for pre-heating resin tablets comprising a resin tablet heater, a switch for setting a reference softening degree and a softening degree detector for the resin tablet. The detector includes a pressure source and a pressure transmitting member coupled to the pressure source and adapted for contact with the resin tablet. The pressure transmitting member is movable a distance representative of the softening degree of the resin tablet being heated due to deformation of the resin tablet.

Abstract: A device for the production of a non-woven product from a fluid dielectric substance, comprising a first electrode, means for leading this electrode along a closed path, driving means to move this electrode along this path, coating means for coating this electrode with the said substance opposite a first portion of the said path, a second electrode whose surface is relatively extensive with regard to the first electrode, located opposite a second portion of the said path, an electrostatic generator connected to one of the said electrodes to establish a potential difference between them so as to create an electrostatic field capable of acting on the said substance to form a plurality of fibers in the direction of the said second electrode, characterized in that it comprises two endless transport bands mounted respectively around guide means defining two closed parallel trajectories passing near the coating means and the said second electrode, these bands being connected to the said driving means so as to move

Abstract: An apparatus and method for molding thermosetting material into shaped articles rapidly and without the occurrence of hot spots or other defects. A mold having a cavity conforming to the shape of the article to be molded is provided and is filled with thermosetting material. An energy source generates electromagnetic energy in the microwave range and a coupling means is provided for causing the electric field component of the generated energy to uniformly irradiate the volume of thermosetting material in the mold cavity.

Abstract: The present invention relates to methods for shaping compositions comprising materials containing at least one electrically conductive material, dispersed in substantially non-electrically conductive plastic materials selected from thermosetting resins, thermoplastic resins and elastomers. With thermosetting resins, shaping is accompanied by curing.

Abstract: A heated mold panel for casting concrete has a rigid base providing a base surface, a substantial part of which is grooved by interconnecting grooves, has a continuous heating element laid in the grooves, and the base surface is covered with a non-porous, non-corrosive material that provides a smooth outside surface covering the base surface, spanning the grooves and enclosing the element in interconnecting passages defined by the grooves and the covering material. Sufficient clearance is provided in said passages around the element for air to flow freely from passage to passage, whereby heat flow from the element to the concrete poured against the outside surface is by radiation from the element and by convection of air flowing in the passages around the element.

Abstract: The wrapped insulation of coils of large electric machines--motors or generators--is set by heat and pressure in a press that extends the length of both wrapped legs of the coil and supports the coil so that it is substantially free from stress. The coil may be supported with its wrapped legs level and horizontal, and the press can be adjustable for different coil sizes and configurations. The heat and pressure cycle is operable automatically to suit the requirements of the insulating material.

Abstract: Friction or antifriction material for use in brakes, clutches, bearings and the like is shaped and cured in a mold containing a mixture of a substantially non-electrically conducting heat bondable friction or antifriction material composite with at least one electrically conductive material dispersed throughout the mixture. The mold is closed to confine the mixture and at least two electrodes are placed opposite sides of and electrically connected with the mixture. An electrical potential is applied to the electrodes to pass an electric current substantially throughout the mixture to effect resistance heating, shaping and curing of the mixture within the mold. The heat input to the mixture is monitored to control the total heat input to a predetermined value required for effecting shaping and curing of the mixture. The maximum electric current passed through the mixture can also be controlled.

Abstract: Apparatus for molding crayons and the like having particular utility in reclamation of broken and worn crayons and molding thereof into new crayons. Means for supplying radiant and convective heat are surrounded by a housing, with a plurality of chutes positioned beneath the heat supply means, each chute having an orifice communicating with a mold cavity into which molten wax flows by gravity. The apparatus has no moving parts and is simple and safe for use by children.

Abstract: A non-woven fabric or film of thermoplastic material has a pattern impressed on its surface so that it has a more pleasing appearance. The film is pressed between the patterned surfaces of two mold bands and is passed through an electromagnetic field which heats a susceptor material in the film to soften the fabric or film so that the pattern will be impressed in it.

Abstract: Elastomer waste may be devulcanized without depolymerization to a material capable of recompounding and revulcanization into a product having physical properties essentially equivalent to the original vulcanizate. Devulcanization is accomplished by application of a controlled dose of microwave energy to sized material, preferably in a continuous process.

Abstract: Disclosed is a process for the uniform cure of polyurethane elastomers including the steps of mixing polyurethane prepolymers, having free isocyanate groups, with a stable curing agent complex to form a blend, thereafter transferring it to a suitable mold and subjecting it to a predetermined amount of microwave energy until it is substantially cured.

Abstract: The present invention is related to a method for producing a planar heating element. The method comprises melt-admixing an insulating thermoplastic resin with an electrically conductive powder. The mixture is then extruded, and the extruded body is rapidly cooled.

Abstract: A method of extruding plastic film is provided which employs a die comprising a die body having an inlet therein for receiving a plastic melt under pressure and having an annulus in the die in flow communication with the inlet and having a discharge orifice for extruding the plastic melt therefrom in tubular form. A heat conductive band is provided and supported by the die body and such band has a circumferential heat conductivity which is better than its radial heat conductivity; and, a heater is employed for heating the band with the band assuring heat is transmitted so that practically all points of an annular portion of the die body located immediately adjacent the band are substantially at the same temperature.

Abstract: A technique for the repair of selenium photoconductor elements is disclosed. The particular method includes applying a concentrated heat source to a damaged area of the photoconductor in an oscillating motion traverse to the damaged area so as to effect a weld of same. The oscillating motion of the heat source enables quick melting and resolidification of a minute area of selenium wihout undesirable recrystallization of the photoconductor.

Abstract: A burn-resistant article transparent to microwaves and suitable for use in a microwave oven, either as a receptacle for supporting articles to be heated, for shelving, housing or parts of housing, is prepared from a sheet molding composition.

Abstract: A peroxidic-initiated graft copolymerization process wherein a water-insoluble thiocarbonated or thiocarbamated substrate is exposed to high-frequency microwave energy in the presence of at least one ethylenically unsaturated monomer and a perioxidic free radical initiator.

Abstract: A method of moulding a drum or similar from a thermoplastic resin in powdered form, in which an appropriately shaped mould, after introduction of the thermoplastic material, is subjected to the actions of alternate direction rotation, tilting, heating and cooling in a predetermined sequence with the heating of the drum body and ends being effected and controlled independently.