Abstract: The present invention relates to a cooling apparatus for an electronic device, in which a cooling solid body in close contact through thermal conductive fluid with a heat transfer portion of the electronic device is provided, on its one surface in contact with the electronic device, with a number of grooves communicating with the outside of the heat transfer portion, and a spring member for elastically pressing this cooling solid body on the electronic device is provided for forcing the cooling solid body into close contact with the electronic device by means of the thermal conductive fluid in a third layer.

Abstract: A method of feeding pure water under germ-free conditions is provided by purifying raw water into primary water by successive passage through a defined series of purification units, temporarily storing the primary water in a primary water tank, further purifying the stored water to still higher purity by passage through a defined series of purification units; injecting HF or a salt of HF into the thus-purified water in bacteriostatic and sterilizing concentrations and then feeding it to its point of use.

Abstract: Periodical sterilization is usually needed in the ultrapure water line provided in an ultrapure water-producing system or plant to kill some occasionally occurring viable cells of microorganisms in the ultrapure water as produced or being produced and thereby keep the ultrapure water under germ-free conditions. Now, it is discovered that an aqueous solution containing 1 to 100 ppm of hydrofluoric acid is effective to sterilize the ultrapure water line and is advantageous over the conventional sterilization agents such as aqueous hydrogen peroxide and sodium hypochlorite which were employed normally for the sterilization of the ultrapure water line.

Abstract: In a liquid cooling system comprising cold plates attached to their respective circuit modules, quick couplers are provided for connecting flexible hoses to these cold plates, a supply duct and a return duct to form strings of cold plates connected between the supply duct and the return duct. Valved quick couplers are used for the connection to the supply duct and the return duct, and valveless quick couplers are used for the connection to the cold plates. When a circuit module is to be serviced, a desired string of cold plates is disconnected from the supply duct and the return duct by disjoining the valved quick couplers for the connection thereto. The disconnected string of cold plates is drained of the coolant, and then the cold plate attached to the desired circuit module is disconnected from the hoses. Subsequently the desired circuit module and the cold plate attached thereto can be detached as one body from an associated connector.

Abstract: A cooling structure for cooling a multi-chip module by a heat sink is disclosed in which the heat sink is disposed above the multi-chip module in a state that heat-conductive grease is sandwiched between the heat sink and the module cap of the multi-chip module, and the heat sink, the module cap and the wiring board of the multi-chip module are clamped as one body by clamp member, and in which a heat-sink pushing member for pressing the heat sink against the module cap by a constant force is attached to the clamp members.

Abstract: A first mother board among a plurality of mother boards is mounted adjacent to a reference mother board and a second mother board among said plurality of mother boards is mounted in a position rotated 180.degree. about the horizontal centerline of the second mother board and mounted back to back to the first mother board, whereby the reference mother board and the first and second mother boards can be interconnected at a minimal distance.

Abstract: A cooling system for an electronic apparatus comprises a plurality of mother boards each having a circuit board to be cooled, a blower for causing an air flow from one of the mother boards to the other, and a draft duct for directing the air flow between the mother boards.The draft duct includes an inlet for dividing the air flow into a plurality of partial flows, a partition for changing an air flow direction of the partial flows into some other directions, and an outlet for intermixing the partial flows.

Abstract: In a cooling structure for electronic apparatus in which cards consisting of electronic components mounted on circuit boards are arranged in parallel on a motherboard. A pressure adjustment device with holes is arranged in a cooling air flow passage of each card. The area of the holes is selected in relation to the pressure loss characteristics of the related card based upon average air-flow sectional area.

Abstract: A flux for brazing the aluminum parts characterized by comprising 5 to 95 wt. % of K.sub.2 AlF.sub.5 or K.sub.2 AlF.sub.5.H.sub.2 O and the remainder of KAlF.sub.4 and preparing method of the same.