Abstract: As used in an apparatus for thermal treatment of semiconductors, a treating tube has a flanged portion at one end, near an outlet for a treating gas, and a sealing closure has a cylindrical portion and a flanged portion. The flanged portion of the sealing closure is adapted to be interfitted with the flanged portion of the treating tube so as to seal said end. The sealing closure is removable so as to open said end. The cylindrical portion is adapted to be inserted into the treating tank through said end so as to substantially fill the treating tube, as far as the cylindrical portion extends into the tube, except for a clearance provided around the cylindrical portion, between the cylindrical portion and the treating tube, whereby formation of convection currents in the treating gas is prevented. The flanged portion of the treating tube, a hollow interior of the sealing closure, and the flanged portion of the sealing closure are open to an outer atmosphere when the flanged portions are interfitted.

Abstract: A heating element for use in an electric blanket or the like including conductors spaced apart in a positive temperature coefficient (PTC) material which serves as a self-limiting heater. The conductors are separated by a spacer which prevents the conductors from engaging each other when the PTC material softens or melts during annealing thereof. A coating of material having a higher melting point than the PTC material is placed over the PTC material to maintain its shape during the annealing process.

Abstract: A hand held hair dryer housing with a relatively small open end and a relatively large opposite open end, heater means, and a reversible motor-driven fan for selectively providing either a concentrated or a diffused flow of heated air through said small or large open ends of said housing, respectively.

Abstract: A heating cable having spaced helically wound conductor wires separated by a layer of positive temperature coefficient material which functions as a self-limiting heating element. At least one of the conductor wires is helically disposed on a stranded core of insulating fibers which have been coated and impregnated with conductive carbon.

Abstract: A door opening mechanism for partially opening a door on a toaster oven wherein the oven includes a thermal timer for controlling the operation of the oven in a toast mode. The door opening mechanism includes a first lever held in a first position by the timer wherein the first lever is released upon termination of the toast mode. The mechanism further includes a resiliently biased slide held in a first position by the first lever and released to a second position upon completion of the toast mode. The slide is mechanically coupled to a lever assembly that includes second and third levers and a cam lever. The third lever and the cam lever are mechanically coupled to the oven door and are resiliently held in a first position to hold the door closed and resiliently moved to a second, door open position upon release of the first lever. The mechanism turns the mode selector switch to the off position once the toast has been removed from the oven and the door closed.

Abstract: A diffuser attachment which is telescopically assembled to the air outlet end of a hand-held hair dryer and which is characterized by a forwardly flared body portion and by a diffuser plate concentrically mounted within the flared body portion and having a convex surface facing the flow of heated air from the hair dryer.

Abstract: In an electric bedcover of a type wherein a safety thermostat having a bimetallic element is adapted to deenergize a heater when the bimetallic element is heated sufficiently, as when an overheated condition occurs, an elongated flexible sensor of a type comprising a pair of conductors spaced from each other by a layer of material having a negative temperature coefficient of resistance is adapted to influence the bimetallic element through a resistor, which is mounted for heat dissipation to the bimetallic element, and a first circuit branch comprising the resistor, the conductors, and the layer between the conductors, in series with each other, is connected so as to maintain the conductors at different potentials when the heater operates, and so as to conduct sufficient current to cause the resistor to conduct sufficient heat to cause the bimetallic element to open the contacts when some part of the layer between the conductors is heated so as to act as an electrical conductor having a low impedance rather t