Abstract: An apparatus for transmitting energy to and from superconductive coils, via a unipolar capacitor having a large capacitance. The apparatus is characterized by the use of two on-off self-controllable switches which are turned on and off under instructions from a control circuit or the like. The control circuits assure that the capacitor voltage remains constant by operating the switches in response to detected voltage levels.

Abstract: A circuit for transmitting energy to and from coils is improved by connecting a coil to a bridge circuit composed of a diode and a switch such as a gate turn-off thyristor. An opposite polarity switch and diode construction may be used in addition to selectively allow the direction of current flow through the coil to be reversible.

Abstract: A semiconductor element is disposed within a hollow cylindrical, electrically insulating member. The member has each of opposite open ends closed with a respective electrode of the element and a piece of thin sheet metal to form an annular space on either side of the semiconductor element. A silicone rubber layer is attached to that surface of the metallic piece facing the semiconductor element, and a high thermally resisting ceramic annulus is buried in the layer.

Abstract: A semiconductor device is carried in compressive contact relationship between two vapor cooling containers put in fluid communication with condensers disposed above them through connection tubes respectively. A condensible liquid coolant fully fills each container, and the associated connection tube and partly fills the mating condenser. One auxiliary tube is disposed within each connection tube and has a bent upper end opening in the associated condenser below the liquid surface of the coolant and a lower end opening in the associated cooling container connected thereto.

Abstract: Within a refrigerant two planar semiconductor elements are sandwiched between two cooling member while another cooling member is interposed between the elements. The interposed cooling member includes three through holes vertically running through it and each of the outermost cooling members includes three grooves vertically extending throughout that surface remote from the semiconductor elements. An axial hole may be provided on each of the cooling members.

Abstract: A semiconductor device is immersed into a cooling medium in its liquid phase disposed in a vessel. The cooling medium changes to its vapor phase due to heat from the semiconductor device to enter a condenser located above the vessel. The cooling medium condensed in the condenser passes through a conduit connected to the lower portion of the vessel to be directly mixed with the liquid cooling medium within the vessel.

Abstract: A plurality of semiconductor elements alternating with hollow heat dissipation blocks are connected together into a unitary structure by means of a fastening mechanism and disposed below a coolant reservoir. The hollow blocks are connected in fluid communication to the reservoir through individual connection tubes including respective bellows-shaped tube portions. A body of boilable liquid coolant is charged into the reservoir and fills both the connection tubes and hollow heat dissipation blocks. A condenser is disposed in fluid communication relationship with and above the reservoir. The condenser may be disposed within the reservoir.

Abstract: A plurality of semiconductor elements alternating in compressive contact relationship hollow heat dissipation blocks are disposed below a coolant reservoir filled with a condensible coolant in its liquid phase having a liquid surface. The hollow blocks are connected to the reservoir through respective connection tubes to be filled with the liquid coolant. A condenser is disposed above the reservoir. One auxiliary tube is disposed within each connection tube and has an upper open end located below the liquid surface and short of a point where a condensed coolant from the condenser flows into the reservoir and a lower end opening within the associated block.