Abstract: A heat insulating box of a refrigerator includes a non-flammable heat-insulator particularly a vacuum heat-insulator made of a board-shape molded inorganic fiber. Therewith non-flammability of the heat insulator is ensured and a refrigerator box prevented from catching an outside caused fire is achieved, thus a refrigerator which is safe even when a flammable refrigerant is used and which is high in energy-saving is provided.

Abstract: A vacuum heat insulator according to the present invention includes a core molded to be plate-shaped with the use of a binding agent. The vacuum heat insulator assumes any one of the following configurations. A) The core is formed by curing a fiber aggregate by means of a binding agent. The fibers have an average fiber diameter of at least 0.1 ?m but at most 10 ?m, and voids defined by fibers have a void diameter of at most 40 ?m. The core has a percentage of the voids of at least 80%. B) The binding agent is varied in concentration in a through-thickness direction of the core. C) A cured layer solidified by the binding agent is formed on at least one side surface of the core. D) The core contains fibers having a length of at most 100 ?m. The fibers are oriented perpendicular to a direction of heat transmission. Such vacuum heat insulator is excellent in adiabatic property.

Abstract: In a linear compressor having a compression mechanism for compressing and discharging a refrigerant, an inflammable refrigerant or a natural refrigerant such as propane, isobutane, carbon dioxide or the like is used as the refrigerant while no lubricating oil is filled up, thereby improving the system efficiency and reducing the amount of refrigerant.

Abstract: An enclosed motor-driven compressor includes a vertical crankshaft rotatably supported by two ball bearings and having an eccentric portion through which a motor element and a compressor element are operatively connected. The two ball bearings are disposed on opposite sides of the eccentric portion so that a reaction force of a piston which is exerted on the eccentric portion is supported evenly by the ball bearings. With the ball bearings thus arranged, the load on the crankshaft is lowered and the efficiency of the motor element is increased. A lubricating oil held at the bottom of a container is sucked through an internal groove of the crankshaft and then supplied from outlets to the respective ball bearings. The ball bearings thus lubricated have a prolonged service life. The compressor may have an oil sump disposed either above or below the ball bearing for improving lubricating condition of the ball bearing.

Abstract: This invention relates to a foamed heat insulation material for refrigerators and freezers which makes it possible to reduce the quantity of a fluorocarbon foaming agent used therein. Said foamed heat insulation material is obtained by mixing a carbon dioxide adsorbent prepared by treating the surface of the carbon dioxide absorbent so as to make it hydrophobic with a water-containing premix component and an isocyanate component and stirring the resulting mixture.The foamed heat insulation material thus obtained can reduce the quantity of the fluorocarbon foaming agent at the time of foaming owing to the use of water as a foaming agent, and after the foaming, can adsorb off with the carbon dioxide adsorbent the carbon dioxide generated by the isocyanate-water reaction and thereby purify the gas in foams into a fluorocarbon gas.

Abstract: A heat insulating body comprising a rigid polyurethane foam of open cell structure, and a vessel formed of metal-plastics laminate film enveloping said rigid polyurethane foam, the whole system being evacuated to reduce the internal pressure and then hermetically sealed; and an adiabatic box comprising said heat insulating body, an inner box and an outer box, said heat insulating body being disposed between said inner box and said outer box and the whole system being subjected to integral foaming with rigid polyurethane foam.