Abstract: Disclosed is a multiple stage cryogenerator including a cryopump system in which a thermally conductive bridge between a pumping assembly and a low temperature stage is somewhat lengthened in order to reduce the length of a conductive bridge between a higher temperature stage and a radiation shield for the pumping assembly. The thermal gains produced by reducing the length of the latter bridge outweighs considerably the thermal losses caused by lengthening the first bridge so as to substantially improve the overall thermal efficiency of the system.

Abstract: A device for maintaining a vacuum in a compartment of a rotating member includes a collector which is mounted over an orifice of the rotating member. The collector has an end wall with an annular aperture extending axially of the rotating member. The aperture is selectively sealed by an annular valve member which permits communication of the compartment with a high-vacuum pump. The valve member may be of a magnetizable material and may be moved axially by a fixed control coil. Sealing members are provided for sealing the compartment of the rotating member with respect to a fixed member when the compartment is in communication with the vacuum pump.

Abstract: A method of cooling a moisture-containing foodstuff article is described, which involves placing the article in a chamber and evacuating the chamber to reduce the pressure in the chamber, whereby moisture evaporates from the article and the latent heat of the moisture is extracted from the article. In order to prevent damage to the article by a too-rapid evaporation, the evacuation is controlled in response to dimensional change (typically the height) of the article.The invention also includes a method of controlling the evacuation of the chamber by progressively opening a valve in the pumping system to reduce the impedance (and hence increase the pumping rate) of the pumping system. This progressive opening of the valve is however, subject to an over-riding control which may arrest the opening action or initiate closing of the valve in response to a detected dimensional change of the article.

Abstract: A partial pressure condensation pump for increasing the partial pressure of a gas or gases in a gas-vapor mixture, without mechanical pumping, while removing a vapor or vapors from the mixture and while conserving the relative abundances of the gaseous species present. More particularly, the invention comprises a pump which includes a housing providing a flow passage having an inlet and an outlet at the downstream end thereof, a vapor condenser in the flow passage downstream from the inlet, means for suppressing back diffusion of gas toward the inlet, and outflow metering means controlling flow through the outlet for balancing the outgoing gas flow through the outlet and the incoming gas flow through the inlet.

Abstract: Cryopumping speed of nitrogen, helium, hydrogen and neon can be increased by omitting the chevron baffle in a conventional cryopump and preventing incident radiation of about 300.degree. K. from striking surfaces used to cryosorb helium, hydrogen and neon. An apparatus is disclosed utilizing three pumping surfaces created from open ended opposed nested cylinders. A radiation absorbent coating is placed on one of the surfaces to shield the helium, hydrogen and neon pumping surface. Refrigeration can be provided by a two-stage closed cycle cryogenic refrigerator.

Abstract: A multiple stage cryogenic vacuum pump is disclosed for transferring matter or species between a gas and a vacuum chamber. The vacuum chamber has an orifice through which the matter or species moves and through which some of the gas leaks into the chamber. The chamber also has an interior surface which is spaced from the path of movement of the matter or species and encircles such path, and an internal divider extending to a position adjacent the interior surface and dividing the chamber into a first region adjacent the orifice and a second region downstream from the first region, with the interior surface extending in both regions. The surface is cooled by a single refrigerating device to below the condensation temperature of the gas, to produce a pressure below atmospheric in the first region and a lower pressure in the second region. The divider contains an aperture through which the matter or species travels and may itself be cooled to precool gas contacting it.

Abstract: A closed loop apparatus for spraying coolant against the back of a radiation target. The coolant is circulated through a closed loop with a bubble of inert gas being maintained around the spray. Mesh material is disposed between the bubble and the surface of the liquid coolant which is below the bubble at a predetermined level. In a second embodiment no inert gas is used, the bubble consisting of vapor produced when the coolant is sprayed against the target.

Abstract: A cryopump having a generally axially symmetrical housing provided at one end with an entrance opening defined by a plane for passage of molecules of the gas to be pumped and plates defining condensation surfaces arranged to be brought to low temperature for condensation of molecules of the gas to be pumped, and a thermal radiation shield disposed in the region of the entrance opening, with the condensation surfaces being oriented substantially at right angles to the plane of the entrance opening and the radiation shield being composed of a plurality of elongate metal strips so positioned that their longitudinal axes are parallel to the condensation surfaces.

Abstract: In the dispensing of gasoline into a tank used for the storage or transportation of gasoline wherein the gasoline displaces a gaseous mixture of air and gasoline, and said mixture is treated to a recovery step to separate said gasoline from said mixture, there is provided an improvement in the recovery step which comprises cooling said mixture to condense out the gasoline and water from the air thereby purifying the air, and then separating the water from the gasoline.

Abstract: An air conditioning system for building utilizes a vertically aligned, generally straight conduit rain tower for scrubbing and pumping air between the exhaust air conduit system and the supply air conduit system in conjunction with an evaporative water chiller utilizing a venturi to create a vacuum in the water chiller for low temperature vaporization of return water. Gravity flow of water through the venturi is used to create the suction head.

Abstract: The invention provides a high vacuum pump system of high pumping speed in which the surfaces that are to be cooled are coated with adsorbents in such a manner that it is possible to bale out and activate the coatings at temperatures between 250.degree. and 400.degree. C and then to use them for the maintenance or repeated generation of high vacua containing no hydrocarbons down to pressures as low as about 10.sup.-8 torrs.

Abstract: The invention relates to a regeneration-type cryopump which has an annular reservoir for liquid nitrogen situated above an annular reservoir for liquid helium and incorporates, sliding in the central opening in the said reservoir, a valve member which is mounted on a rod. When the valve member is in one position, the cryopump is in normal operation, whereas when the valve member is in another position and rests against a seating, regeneration may take place.Such a pump may be used for generating very high vacua.

Abstract: The preservation of metabolically active matter such as fruit, vegetables, meat, fowl, shrimp, fish, other food, cut flowers, cuttings, foliage plants and the like is disclosed, characterized by storage at controlled and correlated conditions of hypobaric pressure, temperature, humidity, air circulation and air exchange. A non-deleterious gas such as air is humidified by contacting it with heated water from a supply, and then the humid air is passed through, and when advisable, recirculated and/or rehumidified within a storage chamber containing the metabolically active matter. The relative humidity is maintained within the range of about 80 to 100 percent and the pressure is maintained continuously or intermittently at a selected value at least slightly higher than the vapor pressure of the water in the stored commodity.

Abstract: A method and apparatus for venting cryogenic storage tanks. In the method, a non-flammable, non-combustion supporting, relatively warm gas is mixed with cold vapors vented from a cryogenic storage tank to warm the vented vapors to a characteristic density less than that of the air adjacent the tank. The apparatus employed includes a vent pipe having a Venturi ejection throat therein, a pressure relief valve spaced from the ejection throat, and a gas ejector nozzle extending into the vent pipe between the safety relief valve and the ejection throat.

Abstract: The preservation of metabolically active matter such as fruit, vegetables, meat, fowl, shrimp, fish, other food, cut flowers, cuttings, foliage plants and the like is disclosed, characterized by storage at controlled and correlated conditions of hypobaric pressure, temperature, humidity, air circulation and air exchange. A non-deleterious gas such as air is humidified by contacting it with heated water from a supply, and then the humid air is passed through, and when advisable, recirculated and/or rehumidified within a storage chamber containing the metabolically active matter. The relative humidity is maintained within the range of about 80 to 100% and the pressure is maintained continuously or intermittently at a selected value at least slightly higher than the vapor pressure of the water in the stored commodity.

Abstract: A portable refrigerating unit has a condenser coil which may be inserted directly into the drying chamber of a freeze drying apparatus. A flexible tube is utilized to convey refrigerant to and from the condenser coil. The flexible tube and the condenser coil are connected through a closure member, which provides a vacuum tight seal for the drying chamber of the freeze drying apparatus. The closure member may be removed from the condenser coil, so that various closure sizes may be utilized and so that the condenser coil may be utilized as an immersible refrigerating device.