Abstract: The present invention generally relates to an RFID inventory and expiration date tag for an in-cabin airline metal chemical oxygen generator canister or other in-cabin assets (such as canisters) and a method of using the same. The tag is especially suitable for use in connection with metal oxygen or other gaseous metal canisters used in the aerospace industry. The RFID tag allows for the rapid, efficient, accurate, frequent and easy monitoring of the expiration date of the oxygen generator. The tag has a plurality of stacked layers including layers of polypropylene, polyester, UHF Inlay, fire retardant polypropylene and an acrylic adhesive. The tag extends directly outward from the generator at a tangent to approximately a ninety degree angle with respect to the generator.

Abstract: A pressurized supply of oil for lubrication and other purposes for a helical screw compressor is automatically and continuously maintained in an oil separator in the compressor discharge line by a check valve assembly which is controlled by the pressure differential between the compressor inlet and the condenser, a bypass around the valve's control element permitting equalization of pressure on its opposite sides to permit closing by a biasing element.

Abstract: An ice builder coil has two or more coil sections, one above the other, supplied with refrigerant from a low pressure receiver, each coil section having an individual vapor return line to the low pressure receiver, the flow through the lower coil section being controlled by an ice thickness sensor associated with the lower coil section.

Abstract: An oil separator, for use in the compressor discharge of a refrigeration system, has a turbine wheel on which refrigerant vapor impacts positioned within a vessel so that the oil is slung outwardly and impinges on the side walls of the vessel and the oil-free vapor is deflected 180.degree. to flow upwardly through the turbine wheel for discharge from the vessel.

Abstract: A flow control valve in a unitary casing has a seat for a manual stem valve on one side of the valve opening and a seat for a check valve on the other side, the check valve being lightly urged toward closing position against differential pressure in the flow stream and being receptive to external pressure control.

Abstract: An axial flow helical screw compressor with a slide valve and slide stop mounted end to end in communication with the intermeshing rotors has means for changing the volume ratio during operation by stepwise movement of the slide stop and for changing the capacity during operation in infinitely variable fashion, both in response to system operating conditions. In the event of interference between the movements of the slide stop and slide valve, the components are designed so that the movements of the slide stop overpowers that of the slide valve.

Abstract: Fragmentary water ice is produced in an enclosure by metering water into a flowing body of liquid refrigerant having a greater density than the water or ice, lifting the ice out of the refrigerant and through a zone of further cooling in which the adhering liquid refrigerant, itself, is cooled and drained from the ice, and discharging the ice through an opening in the enclosure.

Abstract: A variable volume ratio screw compressor has a side load inlet port for the injection of refrigerant vapor into the interlobe volume. In order to improve efficiency, overcompression and undercompression are avoided by varying the location of the radial discharge port to give the compressor an internal volume ratio matched to the pressure of the system in which the compressor operates. This is accomplished in the present application by locating a pressure sensing port no earlier than and preferably later in the compression than the side load injection port, but early enough in the compression that it will not communicate with the discharge port. The pressure that is sensed in the sensing port is used to predict the actual peak pressure in order that maximum efficiency may be obtained as a result of matching the internal volume ratio to the pressure ratio of the system.

Abstract: A method of cooling the oil in screw compressors equipped with automatic variable volume ratio by automatically relocating the proper ports for the injection of liquid refrigerant into the interlobe volume of the compressor in response to the instantaneous internal volume ratio so that the refrigerant injection is done at an optimum time to insure efficient use of the refrigerant.

Abstract: A method of operating an electric drive motor for an axial flow helical screw type compressor having a slide valve member and slide stop member mounted beneath the intermeshing rotors such that the slide member controls communication between the work chamber defined by the rotors and the casing to the outlet port and the slide stop member and the valve member together control the working fluid inlet to the bores of the rotor by sensing the drive motor current and full load operation of the compressor in order to incrementally adjust the slide members in opposite directions depending upon whether or not the motor current is increasing or decreasing to thereby continuously seek the position of the slide members at which such current is at a minimum.

Abstract: An axial flow helical screw type compressor has a slide valve member and slide stop member mounted end to end beneath the intermeshing rotors such that the slide valve member controls communication between the work chamber defined by the rotors and the casing to the outlet port and the slide stop member and the valve member together control the working fluid inlet to the bores of the rotors, the slide valve member and the slide stop being independently movable. Control means for the slide valve member and slide stop include position sensing means for these two members, inlet and outlet pressure sensing means, and means for feeding these inputs into programmable circuitry to control the positions of the slide member and slide stop.

Abstract: An axial flow helical screw type compressor has a slide valve member and a slide stop member mounted end to end beneath the intermeshing rotors such that the slide valve member controls communication between the work chamber defined by the rotors and the casing to the outlet port and the slide stop member and the valve member together control the working fluid inlet to the bores of the rotors, the slide valve member and the slide stop being independently movable. Control means for the slide valve member and slide stop include position sensing means for these two members, inlet and outlet pressure sensing means, and means for feeding these inputs into programmable circuitry to control the positions of the slide member and slide stop.

Abstract: An automatic variable volume ratio screw compressor has a plurality of ports for the injection of liquid refrigerant into the interlobe volume. These ports communicate with the interlobe volume at different effective distances from the discharge port so that the injection of liquid refrigerant may be done at the latest possible time during compression for effective use of the refrigerant, and without risking exposure to the open discharge port.The selection of the port is done automatically in response to the instantaneous internal volume ratio.

Abstract: A radial and thrust bearing mounting particularly adapted for a helical screw type compressor, is provided in which the radial load is isolated from the thrust load to prevent the thrust bearing from carrying any substantial radial load, and in which adjustment of the axial discharge end clearance between the faces of the rotors and the discharge end of the housing cover is provided.

Abstract: The high pressure end wall of an axial flow helical screw type compressor has a slide member which is movable transversely of the rotors for controlling the size of the discharge passage through the end wall and is controlled by sensing means responsive to the pressure at the end wall and in the discharge area in order that full compression which is substantially equal to the pressure at discharge may be obtained.

Abstract: A compressor that uses an excess of lubricant for sealing and cooling is driven by a natural gas engine and pumps natural gas to a transmission outlet, the lubricant drawing off moisture from the gas and portion then being pumped through a circuit in which moisture is removed after which the lubricant is returned to the compressor.

Abstract: A counterflow evaporative heat exchanger employs parallel vertical uninterrupted coil containing sections having the sides thereof arranged to increase the area of liquid contact within the tubes, the smooth flow of a liquid film on the outside of the tubes, and to increase the impingement of gases against the outsides of the tubes thereby providing smooth liquid flow the full vertical length of each section and permitting the use of maximum air velocity with turbulence but with a minimum of liquid entrainment in the gas stream, thereby enhancing cooling of the internal liquid and reducing the space required for the coil assembly.

Abstract: A method of making ice in a tube shell ice-maker that has a false bottom compartment in which trapped refrigerant gas is present to prevent ice formation around the bottom during ice-making and from which hot gaseous refrigerant flows upwardly into the refrigerant within the tubes during defrosting, the liquid remaining within the tubes, whereby delay in initiating further ice-making is minimized.

Abstract: Heat is recovered in a medium at higher than normal condensing temperature of a refrigeration system by using two cascade connected refrigeration systems and heating the medium in isolated stages by refrigerant subcooling and refrigerant condensing stages of the higher temperature system.

Abstract: A shell and tube ice-maker has a bottom compartment in which trapped refrigerant gas is present to prevent entry of liquid refrigerant into the compartment during ice-making and from which, during defrosting, hot gaseous refrigerant flows upwardly into the liquid refrigerant which remains in flooded condition around the tubes, whereby delay in initiating further ice-making is minimized.