Abstract: A hybrid temperature control system for controlling the temperature of the air in a conditioned space, and including a mechanical temperature control unit having primary evaporator means for reducing the temperature of conditioned space air, the first evaporator means utilizing a refrigerant to remove the heat from the air; the hybrid temperature control system further comprising supplemental evaporator means located a distance from the primary evaporator means, the supplemental evaporator means utilizing a cryogen to remove additional heat from the air to further reduce the temperature of the conditioned space air.

Abstract: A rotary vane motor for efficiently extracting mechanical energy from an expanding gas at low rotational speeds is provided. The motor includes a housing having a cylindrical enclosure, a rotor having a plurality of radially oriented slots, a plurality of vanes slidably movable in the slots, a shaft for rotatably mounting the rotor in an eccentric position within the housing enclosure, and a slidable connection between the rotor and the shaft for equilibrating close clearances between the rotor and the side edges of the vanes and the inner surfaces of the housing to minimize inefficiencies due to blow-by and friction. Additionally, the materials forming the rotor, the vanes, and the housing are all selected to have the same thermal coefficient of expansion so that the vanes tightly interfit within their respective slots and the sealing surfaces of the housing over a temperature range spanning the cryogenic temperatures associated with the prefeffed drive gas, and maximum ambient temperatures.

Abstract: A control method is provided for a cryogenic refrigeration system having an evaporator-heater coil, an electronically controlled valve for regulating the amount of cryogen to the coil, and a vapor motor driven by the cryogen that is coupled to both an alternator for recharging a battery, and a fan for generating a discharge air flow through the coil and into a conditioned space. The shaft rpms of the vapor motor is determined by a rectified output of the alternator, and the electronically controlled valve is incremented or decremented so that the shaft rpms stay above a preselected amount sufficient to both to recharge the battery of the system, and to circulate sufficient air in the conditioned space to avoid undesirable temperature non-uniformities therein. The pressure of the cryogen in the system is further continuously measured, and the electronically controlled valve is incremented or decremented in order to maintain a sufficient pressure to maintain the cryogen in a gaseous state.

Abstract: Both an system and method are provided for transferring liquid carbon dioxide from a storage tank pressurized at 300 psi to a truck-transportable tank pressurized at about 110 psi. The system includes an inlet conduit having a hose portion connected between the storage and transportable tanks for conducting a flow of liquid carbon dioxide therebetween, and a vent hose connected to the transportable tank for venting gaseous carbon dioxide. Pressure regulators are connected to the inlet and vent hoses, respectively. In operation, the pressure regulator connected to the inlet conduit reduces the pressure of the flow of liquid carbon dioxide entering the transportable tank from 300 psi to 175 psi, while the pressure regulator connected to the vent conduit maintains a back pressure of 110 psi in the transportable tank while the allowing the venting of gaseous carbon dioxide.

Abstract: Air conditioning and refrigeration apparatus for controlling the temperature of a conditioned space to a predetermined temperature band adjacent to a predetermined set point temperature via cooling and heating cycles utilizing a supply of pressurized cryogen. A cryogen driven motor drives a fan and an alternator. The alternator provides control voltage for operating electrical control devices which select a heating cycle, or a cooling cycle, as required, and which control the flow of cryogen during the selected cycle. Electrical load on the alternator, and thus a load on the vapor driven motor, is minimized to maintain air delivered by the fan to the conditioned space at a level which provides a substantially uniform air flow and temperature throughout the conditioned space. A cryogen flow control valve is motor controlled and only requires electrical energy when a change in the cryogen flow rate is desired.

Abstract: A control system is provided for a cryogenic refrigeration system having an evaporator-heater coil, an electronically controlled valve for regulating the amount of cryogenic gas to the coil, and a vapor motor powered by the cryogenic gas that drives both an alternator for recharging the system battery, and a fan for generating an air flow through the coil and into a conditioned space. The control system includes a temperature sensor for generating an electrical signal indicative of the temperature of the conditioned space, and a microprocessor that is electrically connected to the temperature sensor, the alternator, and the electronically controlled valve for modulating the flow of cryogenic gas through the evaporator-heater coil in said vapor motor to achieve a selected set point temperature in the conditioned space, and to maintain a sufficient alternator current to effectively recharge the system battery.

Abstract: Both an apparatus and method are provided for vaporizing a liquid cryogen and super heating the resulting vapor into a heated gas. The apparatus includes a combustion-type heat source which may burn a fuel such as propane that generates water-containing combustion gases, and a vaporizer coil having an inlet conduit for receiving a flow of a liquid cryogen, such as liquid carbon dioxide, and an outlet conduit for expelling vaporized cryogen. An annular casing surrounds but is spaced apart from the vaporizer coil. The casing isolates the vaporizer coil from contact with water-containing combustion gases generated by the heat source, thereby preventing the formation of unwanted water and ice on the coil, while at the same time transferring heat from these gases to the coil by thermal radiation. A superheating coil is serially connected to the vaporizer coil to further heat the vaporized cryogen.

Abstract: A refrigeration system, which conditions the air of a conditioned space via heating and cooling cycles, includes a heat exchanger and, in a first embodiment, heat pipes. A cryogen is circulated through the heat exchanger during a cooling cycle. During a heating cycle the flow of cryogen is terminated and heat is transferred into the heat exchanger via the heat pipes. In another embodiment, the temperature of evaporation of a liquid cryogen in the heat exchanger is selected according to the desired temperature of the conditioned space, via selectable cryogen flow paths which provide different pressures and thus different evaporation temperatures. Vaporized cryogen drives a motor connected to a fan which circulates air between the conditioned space and heat exchanger.

Abstract: Air conditioning and refrigeration methods and apparatus for controlling the temperature of a conditioned space to a predetermined temperature band adjacent to a predetermined set point temperature via cooling and heating cycles utilizing a supply of pressurized cryogen. A fluid flow path for the cryogen includes a heat exchanger associated with the conditioned space. A cryogen heater is connected in the active cryogen flow path during a heating cycle, and cryogen is directed through the heater and heat exchanger via at least two successive serial passes, utilizing the elevated pressure energy of the cryogen as the motive force.

Abstract: A refrigeration system, which conditions the air of a conditioned space via heating and cooling cycles, includes a heat exchanger and, in a first embodiment, heat pipes. A cryogen is circulated through the heat exchanger during a cooling cycle. During a heating cycle the flow of cryogen is terminated and heat is transferred into the heat exchanger via the heat pipes. In another embodiment, the temperature of evaporation of a liquid cryogen in the heat exchanger is selected according to the desired temperature of the conditioned space, via selectable cryogen flow paths which provide different pressures and thus different evaporation temperatures. Vaporized cryogen drives a motor connected to a fan which circulates air between the conditioned space and heat exchanger.

Abstract: Methods and apparatus for controlling the air temperature of a conditioned space to a selected set point temperature, utilizing a supply of cryogen in liquid and vapor states. The two states are drawn from the supply and maintained in first and second separate, independent flow paths. The liquid cryogen provides a cooling mode for the conditioned space via a heat exchanger disposed in the first flow path, and the vaporized cryogen provides a cooling mode for the conditioned space via a heat exchanger disposed in the second flow path. Cryogen flowing in at least one of the flow paths is used to drive a vapor motor connected to a fan, with the fan moving air between the conditioned space and at least one of the heat exchangers. Heat is applied to the cryogen as required to hold the set point temperature, or to defrost a heat exchanger.

Abstract: A refrigeration system associated with a conditioned space to be controlled to a predetermined set point temperature via heating and cooling cycles. The refrigeration system includes a fluid flow path through which a predetermined liquid is circulated. The fluid flow path includes a slush tank and first and second heat exchangers, with cryogen from a supply vessel being expanded into liquid disposed in the slush tank. The first heat exchanger is disposed to condition the air of the conditioned space, and the second heat exchanger is in heat exchange relation with heating apparatus. The first heat exchanger and slush tank are interconnected when the conditioned space requires a cooling cycle, and the first and second heat exchangers are interconnected when the conditioned space requires a heating cycle. Cryogen of the cryogenic cooling apparatus is thus not expended to heat the conditioned space, or for defrosting purposes.

Abstract: A refrigeration system associated with a conditioned space to be controlled to a predetermined set point temperature via heating and cooling cycles. The refrigeration system includes a fluid flow path through which a predetermined fluid is circulated. The fluid flow path includes first, second and third heat exchangers. The first heat exchanger is disposed to condition air of the conditioned space, the second heat exchanger is in heat exchange relation with cryogenic cooling apparatus, and the third heat exchanger is in heat exchange relation with heating apparatus. The first and second heat exchangers are interconnected when the conditioned space requires a cooling cycle, and the first and third heat exchangers are interconnected when the conditioned space requires a heating cycle. Cryogen of the cryogenic cooling apparatus is thus not expended to heat the conditioned space, nor used for defrosting purposes.

Abstract: A refrigeration system which controls the temperature of a conditioned space to a predetermined temperature range adjacent to a selected set point temperature SP via a cooling cycle which includes evaporation a cryogen, such as CO.sub.2 or N.sub.2, in a heat exchanger. In an apparatus embodiment, a controller determines a desired evaporation vapor pressure value EPX of the cryogen as a function of the selected set point temperature SP, and then controls the evaporation pressure EP in the heat exchanger means as a function of the determined desired evaporating vapor pressure value. The controller further determines a desired superheat value SHX of the cryogen exiting the heat exchanger means as a function of the selected set point temperature SP, and controls the mass flow rate of liquid cryogen evaporating in the heat exchanger as a function of the determined desired superheat value.

Abstract: Methods and apparatus for controlling a conditioned space to a predetermined set point temperature, utilizing a supply of cryogen. Cryogen is drawn from the supply in a flow path to provide a cooling mode via a heat exchanger disposed in the flow path. A vapor motor in the flow path, downstream from the heat exchanger, drives a fan which moves air between the conditioned space and the heat exchanger. Heat is applied to the cryogen downstream from the heat exchanger, after all cooling modes have been performed, to provide the desired fan horsepower, without interfering with a cooling cycle. A by-pass flow path selectively directs cryogen directly to the vapor motor, by-passing the heat exchanger, to provide air circulation in the conditioned space when the temperature of the conditioned space is satisfied.

Abstract: Methods and apparatus for controlling the temperature of a conditioned space to a predetermined set point temperature, utilizing a supply of cryogen in liquid and vapor states. The two states are drawn from the supply in two separate flow paths. The liquid cryogen is vaporized in a heat exchanger, and the two flow paths are then combined. The combined cryogen is used to drive a vapor motor connected to a fan, with the fan moving air between the conditioned space and the heat exchanger. Heat is applied to the cryogen as required to hold the set point temperature or to defrost the heat exchanger. In a preferred embodiment, the cryogen is added to a first vessel at the pressure provided by ground support apparatus, and expanded into a second vessel as a function of system conditions, to provide the supply of cryogen in both the liquid and vapor states.

Abstract: Methods and apparatus for controlling the temperature of a conditioned space, including a supply of cryogen, and a fluid flow path for the cryogen which includes a heat exchanger. A heater is disposed to heat cryogen in the flow path in response to predetermined conditions, and a cryogen pre-heater is disposed to aid the heater. In a first embodiment, the pre-heater is aided by directing warm cryogen in heat exchange relation with cryogen flowing through the pre-heater, with the warm cryogen being taken from a point downstream from the heat exchanger. In another embodiment, the heater generates heated gases as a by-product, with the pre-heater being aided by directing the heated gases in heat exchange relation with cryogen flowing through the pre-heater.

Abstract: A refrigeration system associated with a conditioned space to be controlled to a predetermined set point temperature via heating and cooling cycles. The refrigeration system includes a heat exchanger, air mover apparatus disposed to circulate air between the conditioned space and the heat exchanger, cryogenic cooling apparatus which includes a combustible fuel in a cryogenic state, and heating apparatus. The cryogenic characteristic of the fuel is utilized to implement the cooling cycle, and the combustible characteristic of the fuel is utilized by the heating apparatus to implement the heating cycle. In preferred embodiments of the invention an internal combustion engine is associated with the refrigeration system, and the air mover means includes a vapor motor, with the cryogenic fuel being vaporized and then expanded in the vapor motor to drive same, and with the expanded vaporized fuel operating the internal combustion engine.

Abstract: An electromagnetic clutch, including a contact plate assembly, a rotor adapted for connection to a driven device, and first mounting assembly for mounting the contact plate assembly to a rotatable member associated with a driving device. The first mounting assembly includes compression springs for biasing the contact plate assembly away from the rotor. An electromagnetic assembly overcomes the bias of the compression springs when energized, causing the contact plate assembly to engage the rotor. The first mounting assembly includes resiliently mounted members which allow the contact plate assembly to oscillate circumferentially relative to the rotatable member, in response to torsional oscillations in the driving device. A second mounting assembly mounts each of the compression springs between the rotatable member and the contact plate assembly, isolating the compression springs from damage due to relative circumferential movement between the rotatable member and contact plate assembly.

Abstract: A transport refrigeration system having a frame which supports a refrigerant compressor, a prime mover for the compressor, condenser and evaporator coils, and an air delivery assembly for moving air through the condenser and evaporator coils. The air delivery assembly includes a single shaft having first and second condenser blowers mounted adjacent the ends of the shaft, and an evaporator blower mounted on the shaft between the first and second condenser blowers. A drive arrangement for the air delivery assembly includes a jack shaft between the shaft of the air delivery assembly and the prime mover, with the prime mover being linked to drive the jack shaft, and with the jack shaft being linked to drive the shaft of the air delivery assembly.