Abstract: A furnace for heat treating metal slabs or strips includes a heating chamber through which stock is passed in confronting relationship to an array of jet impingement radiation burners. Combustion is separated from the stock by flat refractory plates having a plurality of holes uniformly distributed thereover which direct uniform jets of combustion products upon the strip or slab. The jets of combustion products heat the work by convection. Also, the refractory jet forming plates are heated to radiance so that heat energy is transferred to the work by radiation.

Abstract: A food cooker is illustrated in the form of a deep-fat fryer, in which the fat is isothermally heated to an operating temperature below a temperature range in which an unacceptably high rate of undesirable decomposition products formation occurs in the cooking liquid. The heat transfer process used is vaporization and condensation of a confined liquid essentially isothermally and substantially at the working temperature. Condensation of the heat transfer vapor takes place at an outer surface of the container for the fat. Heat is applied to the heat transfer liquid remote from the container, which having no heating element or elements intruding into its interior is easy to clean. Heat is transferred to the cooking fat by condensation of the heat transfer vapor essentially only as it is used by the load being cooked. Hot spots are minimized, so that the formation of undesirable decomposition products of the cooking fat is retarded.

Abstract: A water heater has a hot gas conduit forming a heat transfer wall enclosed by a water jacket. A series of baffles within the conduit direct jets of hot gases to impinge upon the heat transfer wall. The baffles thermally expand during operation to engage the heat transfer wall, but are removable as a unit for servicing when the heater is cool.

Abstract: A food cooker is illustrated in the form of a deep-fat fryer, in which the fat is isothermally heated to an operating temperature below a temperature range in which an unacceptably high rate of undesirable decomposition products formation occurs in the cooking liquid. The heat transfer process used in vaporization and condensation of a confined liquid essentially isothermally and substantially at the working temperature. Condensation of the heat transfer vapor takes place at an outer surface of the container for the fat. Heat is applied to the heat transfer liquid remote from the container, which having no heating element or elements intruding into its interior is easy to clean. Heat is transferred to the cooking fat by condensation of the heat transfer vapor essentially only as it is used by the load being cooked. Hot spots are minimized, so that the formation of undesirable decomposition products of the cooking fat is retarded.

Abstract: Food preparation apparatus involves a heat transmitting zone and a heat source located remotely from the transmitting zone. Heat energy is transferred from the heat source to the transmitting zone by a fluid vapor which travels from the heat source to the transmitting zone, condenses upon the transmitting zone and then returns in a liquid state to the heat source.In one described embodiment of this invention, an oven is provided wherein a fluid enclosure within the oven walls confines the vapor which transfers heat energy from a central heat source to heat transmitting surfaces.

Abstract: A vacuum furnace heats articles by radiation from a condenser portion of a heat pipe. The heat pipe further includes an adiabatic portion passing through the enclosing wall of the furnace and an evaporator portion outside the enclosure. The evaporator portion is preferably heated by a gas-fired burner which may surround it, and the heat pipe acts as a flux converter accepting heat outside the enclosure and delivering heat inside the enclosure to the articles to be heated. The condenser portion of the heat pipe may be panel-shaped and is disposed adjacent the articles to be heat-treated. In the more elaborate forms of the invention involving condenser panels, the condenser panel, or each condenser panel where several heat pipes are used, is a cylindrical section which partially, or substantially completely, surrounds the articles.