Abstract: A portable compact sauna wherein a user's body is warmed to sweating primarily by direct absorption of infrared radiation. Broad infrared radiation emitters or sources are placed around the inside of a narrow cabinet so as to be in close proximity to various parts of a seated user. Fins spaced apart less than finger-width on the emitters protect the user from contact with elevated temperatures in the emitters. The emitters, which lend themselves to easy cleaning, are heated by electric infrared heaters having a unique design which eliminates extremely-low-frequency (ELF) electromagnetic field (EMF) normally generated by AC energized electrical heater elements, to provide low extremely-low frequency EMF saunas able to utilize conventional-commercial electrical-energy sources. The emitters protect the heaters. Power wires for the heaters are arranged for low ELF EMF emission, too.

Abstract: A portable compact sauna wherein a user's body is warmed to sweating primarily by direct absorption of infrared radiation. Broad infrared radiation emitters or sources are placed around the inside of a narrow cabinet so as to be in close proximity to various parts of a seated user. Fins spaced apart less than finger-width on the emitters protect the user from contact with elevated temperatures in the emitters. The emitters, which lend themselves to easy cleaning, are heated by electric infrared heaters having a unique design which eliminates extremely-low-frequency (ELF) electromagnetic field (ELF) normally generated by AC energized electrical heater elements, to provide low extremely-low frequency EMF saunas able to utilize conventional-commercial electrical-energy sources. The emitters protect the heaters. Power wires for the heaters are arranged for low ELF EMF emission, too.

Abstract: A portable compact sauna wherein a user's body is warmed to sweating primarily by direct absorption of infrared radiation. Broad infrared radiation emitters or sources are placed around the inside of a narrow cabinet so as to be in close proximity to various parts of a seated user. Fins spaced apart less than finger-width on the emitters protect the user from contact with elevated temperatures in the emitters. The emitters, which lend themselves to easy cleaning, are heated by electric infrared heaters having a unique design which eliminates extremely-low-frequency (ELF) electromagnetic field (EMF) normally generated by AC energized electrical heater elements, to provide low extremely-low frequency EMF saunas able to utilize conventional-commercial electrical-energy sources. The emitters protect the heaters. Power wires for the heaters are arranged for low ELF EMF emission, too.

Abstract: A portable compact sauna wherein a user's body is warmed to sweating primarily by direct absorption of infrared radiation. Broad infrared radiation emitters or sources are placed around the inside of a narrow cabinet so as to be in close proximity to various parts of a seated user. Fins spaced apart less than finger-width on the emitters protect the user from contact with elevated temperatures in the emitters. The emitters, which lend themselves to easy cleaning, are heated by electric infrared heaters having a unique design which eliminates extremely-low-frequency (ELF) electromagnetic field (ELF) normally generated by AC energized electrical heater elements, to provide low extremely-low frequency EMF saunas able to utilize conventional-commercial electrical-energy sources. The emitters protect the heaters. Power wires for the heaters are arranged for low ELF EMF emission, too.

Abstract: A sandwich panel has a core formed of a plastic sheet having columns of equally spaced points displaced from one side, and other columns of similarly spaced points displaced from the other side, the columns on the two sides being interleaved and the points in adjacent columns on the same side being staggered, with the points in the other-side columns being disposed in rows with the oncoming one side column. The displaced points on a side form somehat cone-like structures which intersect the cone-like structures formed by displaced points on the other side to form structures constituting tetrahedrons and octahedrons when assembled and cemented between the layers of a panel. An apparatus and method for forming the core from a heated plastic sheet, involve passing the sheet between two rollers having projections which displace the points to each side. Another apparatus and method involve forming core shapes over stationary projections. Complex and compound structures may be created.

Abstract: A very lightweight sandwich panel is constructed using as the core layer a very thin plastic sheet that has been preformed with projections having broad bonding areas on their free ends for chemically cementing to one outer layer of the panel and with areas between the projections for bonding to the other outer layer. The projections may be made of different cross-sectional shapes, heights, spacings, tilts, profiles, etc., to produce different characteristics in the panel. Differences may even be made in a given sheet to produce a panel having different characteristics in various portions, including shape and function. These characteristics can be predetermined, and the panels may therefore be computer designed. Special panel applications such as airplane wings and thermal boards are comtemplated.