Selective heating and cooling apparatus

Abstract

An improved portable refrigeration apparatus for selectively cooling or heating a limb of a patient or the like, and which includes at least one flexible pad adapted to be wrapped around a bodily limb and which incorporates flexible tubing serving as an evaporator. A separate auxiliary evaporator is positioned downstream of the pad in the cooling mode to insure that all of the refrigerant is evaporated before returning to the compressor. A temperature control system is provided for the pad which, in the cooling mode, includes a by-pass conduit which by-passes the pad, and a temperature controlled valve for selectively opening and closing the by-pass conduit, and so that the refrigerant will flow concurrently through the by-pass conduit and the pad when the valve is opened. A reversing valve is provided for reversing the direction of flow of the refrigerant composition to effect heating of the pad, and in the heating mode, temperature control is accomplished by selectively actuating the reversing valve to switch to the cooling mode. In the preferred embodiment, there is also provided a by-pass pipe and a pressure actuated valve in the pipe, by which the refrigerant by-passes the pad during heating in the event the pressure in the pad becomes excessive. Also, where more than one pad is utilized, there is provided a check valve downstream of each pad during heating, with the valves acting to equalize the temperatures in the two pads during heating regardless of their respective elevations. Still further, the apparatus preferably includes two separate expansion valves, with one being operative in the cooling mode and the other being operative in the heating mode, to thereby permit different pressure settings in the two modes.

Dependencies are inferred from the claim text.