Abstract: An air conditioning system having an evaporator 8 at a location upstream from a compressor. When a compressor is stopped, a refrigerant inlet is closed by an electromagnetic valve 28 and a refrigerant outlet is closed by a check valve 29. A pressure in the closed passageway is detected by a pressure sensor 22. A leakage of refrigerant at the evaporator is reliably detected, which allows the leakage of the refrigerant to be quickly noticed.

Abstract: A control apparatus for a gas injection type air conditioning system that prevents lowering of compressor speed and cycle stoppage under conditions where high pressure is liable to occur. During a system heating mode, a pressure change rate ASP of the high pressure of the refrigerating cycle is calculated. When a pressure change rate .increment.SP rises above a predetermined value, a system electric expansion valve aperture is reduced. Accordingly, by calculation of the pressure change rate .increment.SP, it is possible to control the electric expansion valve in the above manner earlier than in prior art control schemes when there is a sudden rise in the high pressure.

Abstract: Improved refrigeration system, in particular for domestic use, with a compressor (2), a condenser (3), an evaporator (4) and a valve (5) arranged between the condenser (3) and evaporator (4). The system includes a three-way valve (6) between the condenser (3) and the compressor (2) which establishes a bypass (7) between the compressor (2) and the suction pipe (8) of the system (1) during stoppage of the compressor (2) which blocks the reflux of refrigerant contained in the condenser (3) to the compressor.

Abstract: An apparatus for heating or cooling a space comprises a main flow loop including a compressor (1012), an outside heat exchanger (1014), an inside heat exchanger (1016) connected to allow working fluid to circulate therebetween, and a first valve (1026) between the outside heat exchanger (1014) and the inside heat exchanger (1016) selectively to block flow between the outside heat exchanger (1014) and the inside heat exchanger (1016). A first bypass line extends between the outlet of the outside heat (1014) and the inlet of the inside heat exchanger (1016). A thermal storage device (1018) is positioned in the first bypass line. A second bypass line extends between the inlet of the inside heat exchanger (1016) and the outlet of the inside heat exchanger (1016) and communicates with the first bypass line to bypass the inside heat exchanger (1016). A second valve (1030) is positioned in the second bypass line to block flow through the second bypass line selectively.

Abstract: A vapor compression system with set point optimization generates a set of thermodynamic operating parameters such that the system operates with optimum energy efficiency. Based on environmental conditions such as indoor and outdoor temperature as well as thermal load, the set of parameters for steady-state set point is generated. The system also monitors actual system properties in real-time and provides them as feedback to the set point computation module. Based on these actual real-time measurements, a new steady-state set point can be generated to enable the system to continue operating at maximum coefficient of performance upon change in environmental or thermal load requirements.

Abstract: An evaporator for a refrigerant system having a heat exchanging section and a evaporating section of a total flow type having a bottom inlet tank for receiving a refrigerant from the heat exchanging section, a bottom outlet tank for a discharge of the refrigerant and a stack of flatten pipes, each defining a refrigerant passageway of U-shape connecting the bottom inlet tank and bottom outlet tank. The heat exchanging section controls the degree of the dryness of the refrigerant in a range between 0.01 to 0.2. The flattened pipe has an inner thickness in a direction of the stack in a range between 2.0 to 3.0 mm.

Abstract: In a transport temperature control system having a cooling and heating mode of operation an apparatus and method are provided for enhancing the heating capacity during the heating mode of operation. A second expansion valve is provided to connect the higher pressure liquid line to the refrigerant circuit downstream of the evaporator. When additional refrigerant is needed in the heating circuit to increase heating capacity, especially during low ambient temperature operating conditions, the second expansion valve is caused to open to admit more refrigerant to the system. After passing through the second expansion valve low pressure gas is passed to the compressor, optimizing compressor efficiency such that an increased amount of hot refrigerant gas is delivered to the evaporator for enhanced heating capacity.

Abstract: The refrigeration system is provided with a bundle of refrigeration tubes extending through heat exchange fins, with the bundle forming a condenser section, a receiver section and a subcooler section. A sight glass is positioned in the line between the receiver and the subcooler to facilitate the refrigerant charging process. The system also includes a floating head arrangement which allows the condenser pressure to fluctuate with the ambient temperature. A solenoid valve leading to an expansion valve cycles on/off in response to compressor suction pressure. A check valve insures that a column of liquid is always immediately upstream from the expansion valve.

Abstract: A refrigeration cycle comprises a compressor, an indoor heat exchanger, an outdoor heat exchanger, a liquid receiver; and a pressure reducer connected in series to form a closed loop. The liquid receiver and the pressure reducer connected in series are connected between the indoor heat exchanger and said outdoor heat exchanger. A non-azeotropic mixture refrigerant comprising at least two kinds of refrigerant of different boiling temperatures mixed together is charged in and circulated through the refrigeration cycle. The mixing ratio of the azeotropic mixture refrigerant circulated thorough the refrigeration cycle is controlled substantially constant.

Abstract: A refrigeration system, particularly for controlling the temperature of an environment, and presenting a compressor; a condenser; a laminating thermostatic valve; an evaporator; an evaporation pressure control valve interposed between the outlet of the evaporator and an inlet of the compressor; an economizer in turn presenting a laminating orifice downstream from the condenser, and a flash tank with an inlet communicating with the orifice, a liquid-phase outlet connected to the thermostatic valve, and a gaseous-phase outlet connected to an intermediate inlet of the compressor; and a tapping valve interposed between the outlet of the compressor and the flash tank, and which is opened when the pressure in the flash tank falls below a predetermined threshold value.

Abstract: A liquid chiller refrigeration system with two bypass valves (a condenser bypass valve and a vapor bypass valve), a chiller control valve downstream from the vapor bypass valve, and a remote condenser in addition to a primary heat reclaim condenser so that the recovered heat may be directed to alternate locations. The condenser bypass valve facilitates rapid system start up in low ambient temperature; the vapor bypass valve and chiller control valve facilitate steady performance under varying load conditions; and the remote condenser and heat reclaim condenser provide a choice of discharging the heat to a remote location (typically, outdoors), or to the immediate surroundings of the refrigeration system.

Abstract: An air-conditioning apparatus that prevents a state of blowing temperature fluctuation due to magnitude of vehicle speed in a dehumidification mode. A condenser and evaporator are disposed within an air duct, and an exterior heat exchanger is disposed externally. A capillary and check valve are provided in a refrigerant passage between the condenser and exterior heat exchanger, and a capillary is provided in a refrigerant passage between the exterior heat exchanger and evaporator. During dehumidification mode, a four-way switching valve is switched so that the flow passage of refrigerant is from the condenser to the capillary, to the check valve, to the exterior heat exchanger, to the capillary, to the evaporator, and then to an accumulator. In this case, the condenser and exterior heat exchanger function as a refrigerant condenser in a series-connected state, but because in actuality the capillary is provided, the majority of refrigerant discharged from a compressor is condensed by the condenser.

Abstract: Liquid refrigerant is injected into the motor of a motor-compressor to cool the motor. Refrigerant is also injected to control the discharge temperature of the compressor. The refrigerant for controlling the discharge temperature may be either excess refrigerant for cooling the motor or refrigerant injected into the compressor under the control of a thermal expansion valve.

Abstract: A thermostatic expansion valve includes a valve housing having upper and lower passages. In the lower passage a valve member urged by a spring toward a valve seat of a valve port formed therein is provided. At the top of the housing a driving unit for driving the valve member to open and close the port is attached. The unit has a housing partitioned by a diaphragm into upper and lower pressure operating chambers. A diaphragm driving fluid is filled in the upper chamber, and the lower chamber is connected to a refrigerant circulating pipe between an evaporator pressure regulator and a compressor while the upper passage to the pipe between an evaporator and the regulator and the lower passage to the pipe between the evaporator and an condenser. In the housing a valve member driving rod extends from the diaphragm to the port and crosses the upper passage. The top end of the rod is hermetically fixed to the diaphragm and the lower end abuts the valve member against the spring.

Abstract: A refrigeration appliance is provided having at least two refrigeration compartments, each compartment having its own access door. The appliance includes a single evaporator located in a plenum which is selectively in communication with each of the compartments, a single compressor, preferably run by a variable speed motor, and a refrigerant circuit including a series of conduits for providing a flow of refrigerant to the evaporator and compressor. A first restriction device is provided in the conduit connecting the compressor with the evaporator, the restriction device operating at a first pressure level. A second restriction device is also provided in the conduit connecting the compressor with the evaporator, preferably in parallel with the first restriction device, the second restriction device operating at a pressure level higher than the first pressure level.

Abstract: A fan coil unit which includes a housing defining a chamber in which is located a condensation pan, and the condensation pan is snap-secured to a condensation tray mounting board and a fan board.

Abstract: Disclosed is an improved air conditioning system of the type having a refrigerant which sequentially flows through compressor means, condenser means in heat exchange relationship with outdoor air, expansion means, and evaporator means for the direct or indirect cooling of air in a confined space for maintaining the confined air space at a desired set point of temperature and/or humidity. The improvement for maintaining said set point of temperature and/or humidity of the confined space at variable heat loads therein and at variable outdoor air temperature comprises variable speed compressor means responsive to varying outdoor air temperature for attenuating refrigerant mass flow corresponding to lower outdoor air temperature; and expansion means responsive to attenuated refrigerant mass flow for maintaining adequate refrigerant mass flow to the evaporator means for maintaining constant the desired set point of temperature and/or humidity of the confined space at varying outdoor air temperature.

Abstract: Heat pump systems (principally FIG. 3; also FIGS. 5, 7 or 9) comprising, in circuit of fluid, an injected compressor 113, communicating a compressed gas discharge 137 to a condenser 100, communicating an at least partly liquid output 130 to an expansion valve 101, communicating therefrom 131 to a separator 110, communicating liquid therefrom 134 to a capillary tube 111, and communicating gas therefrom 132 to a control valve 112 that is responsive to ambient temperature; 111 communicating the liquid therefrom 135 to an evaporator 102, communicating gas therefrom 136 to an inlet of the injected compressor 113; the control valve 112 communicating gas therefrom 133 to an injection input of the injected compressor 113; and the expansive valve 101 being adjustable 176,171 responsive to the temperature of the gas communicating 136 from the evaporator 102 to the injected compressor 113. Where the fluid comprises a non-azeotropic refrigerant blend (NARB), the system (FIG. 5; also FIG.

Abstract: A hot gas defrost refrigeration system has a compressor, a condenser, a receiver, an evaporator, interconnected by fluid passage means and incorporating valve means to cause refrigerant to flow sequentially through the compressor, condenser, receiver and evaporator to the compressor during the refrigeration cycle. The refrigeration system includes a superheater and defrost passage means, including valve means, connecting the evaporator outlet to the condenser inlet and connecting the condenser outlet through the superheater to the compressor inlet, bypassing the receiver. The passage means connecting the compressor outlet with the evaporator inlet includes a superheat passage in heat exchange relationship with the superheater for transferring heat from the refrigerant discharged from the compressor outlet to the refrigerant delivered to the compressor inlet during the defrost cycle.

Abstract: A refrigeration circuit is provided with a quench line connecting the liquid line and the suction line and containing a QEV. The QEV is controlled responsive to the superheat of the refrigerant supplied to the compressor. By injecting liquid refrigerant downstream of the suction modulation valve and the sensor for the TXV, the system can be operated at low capacity without overheating the compressor oil.

Abstract: Blocking valve for refrigeration or air conditioning systems, of the type which includes: a hermetic compressor driven by an electric motor, a condenser, an evaporator, a capillary tube between the condenser and the evaporator, and a blocking valve between the condenser and the capillary tube. The blocking valve has a housing (42) defining an inside chamber with inlet and outlet passage in fluid communication with the condenser (31) and, respectively, with the capillary tube (32). A magnetic slide (41) installed in the chamber can be displaced between an opening position and a closure position of the valve. Electromagnetic elements (46, 47) assembled in the housing (42) are selectively and automatically energized during a period of time sufficient to cause the displacement of the slide (41) from one operating position to another in accordance with an operating condition of the system, the slide (41) being retained in its operating positions by action of non-electromagnetic forces.

Abstract: The present application relates to a means and method for simultaneously and independently controlling a pressure of a medium including refrigerant pressure of one and a plurality of output devices and for controlling a current input to one and a plurality of output devices in a relationship in accordance with a point temperature setting, a point humidity setting, and a point air velocity setting; enabling the circuit connecting one and a plurality of output devices to be broken upon a predetermined current deviation beyond the current controlled in a relationship to the point temperature, humidity, and air velocity of their respective settings; enabling the automatic resetting of the circuit to the power supply when the predetermined current deviation had been alleviated; enabling one or more output devices including a compressor of a refrigeration circuit to be maintained running after the temperature of a space becomes equal to the point temperature of a temperature setting and after the humidity of a spac

Abstract: A vapor-compression refrigeration system has a continuously operating compressor, with loading on the compressor varied in accordance with conditions and cooling needs. The system avoids any on/off cycling of the compressor or valves in the system, but instead keeps cooling and bypass valves open to varying and proportional degrees depending upon requirements. The system includes several bypass loops, for bypassing coolant fluid to a proportional degree when a desired temperature is approached in a body to be cooled; and when temperature of return gas to the compressor approaches a limit temperature beyond which the compressor should not operate. In the latter case, cool liquid is injected, while expanding and vaporizing, into the hot gas for cooling, to protect the compressor.

Abstract: In a heat pump system for selectively heating or cooling a plurality of zones with a corresponding plurality of zone heat exchangers, the subject invention is used for preventing refrigerant condensate from flooding any inactive heat exchangers. Each zone heat exchanger is typically connected to both a liquid line and a gas line for passing refrigerant therethrough. The invention includes an arrangement of valves disposed only on the liquid line of each zone heat exchanger and eliminates the need for an additional shut-off valve on the gas line. When the heat pump system operates in the cooling mode, each zone heat exchanger functions as an evaporator with the invention operating as an expansion valve, regulating the refrigerant flow entering the heat exchanger to meet the temperature conditioning demand.

Abstract: In a refrigerating apparatus comprising a rotary compressor, a pressure-controlled valve is inserted in a path between a condenser and an evaporator and a reverse flow check valve is inserted between the evaporator and a suction line connected to the input port of the rotary compressor, thereby to eliminate undesirable heat load caused by undesirable flow-in of the refrigerant gas into the evaporator after the rotary compressor stops.

Abstract: The invention relates to a refrigeration circuit which includes a second expansion means and a flow self-operated regulating valve, which controls the quantity of refrigerant to an intermediate suction port of compressor depending on a difference of pressure at the side of inlet from at the side of outlet of the expansion capillary.

Abstract: Disclosed are novel expansion means useful in an air conditioning system of the type having a refrigerant which sequentially flows through variable speed compressor means responsive to varying outdoor air temperature for attenuating refrigerant mass flow corresponding to lower outdoor air temperature and which compresses vaporous refrigerant supplied by evaporator means, condenser means which is in heat exchange relationship with outdoor air for condensing refrigerants circulated from said compressor means, expansion means which expand said liquid refrigerant from said condenser means, and evaporator means which is in direct or indirect heat exchange relationship with air in a confined space for maintaining said confined space air at a desired set point of temperature and/or humidity, said evaporator supplying said refrigerant to said compressor means.

Abstract: A refrigerating apparatus including a refrigerant circuit constituted by a compressor, a condenser, a first expansion device, a gas-liquid separator, a second expansion device and an evaporator which are successively connected. An injection path interconnects an upper part of the gas-liquid separator and a cylinder of the compressor during the compression stroke thereof. An auxiliary path is formed by connecting a solenoid valve closed in the normal operation and an auxiliary expansion device, with the auxiliary path being provided between the gas-liquid separator and the evaporator so as to be parallel to the second expansion device, and connected to the gas-liquid separator at a position higher than the connecting position of the second expansion device to the gas-liquid separator. The solenoid valve is opened when the load on the refrigerating apparatus increases.

Abstract: The present application relates to the means and method for controlling of refrigerant pressure of a refrigeration circuit and for controlling current input to a compressor of one or more refrigeration circuits in an inverse proportional relationship to the point temperature of a temperature setting, thereby enabling the compressors of a plurality of refrigeration circuits connected to a power supply to be broken upon a predetermined current increase beyond the current being controlled in an inverse proportional relationship to the point temperature of a temperature setting; enabling the automatic resetting of the circuit to the power supply when the predetermined current increase had been alleviated; and enabling the compressor of one or more refrigeration circuits to be maintained running after the temperature of an area being conditioned by the compressor of one or more refrigeration circuits becomes equal to the temperature of a temperature setting.

Abstract: A heat pump system comprising a compressor, two heat exchangers, and an expansion device. The expansion device defines two, spaced apart flow passages. A first piston is located in a first flow passage for metering refrigerant flow therethrough at a first flow rate, and a second piston is located in the second flow passage for metering refrigerant flow therethrough at a second flow rate less than the first flow rate. The expansion device includes a valve having a first position, closing the second flow passage to direct refrigerant through the first flow passage, and a second position, closing the first flow passage to direct refrigerant through the second flow passage.

Abstract: The invention relates to a thermostatic expansion valve assembly for refrigeration units. Condenser pressures are normally five to ten times greater in the summer than in the winter. In the assembly hereof the characterostic adjustment curve is made less dependent on the condenser pressure by reason of having two flow restricting zones in series in which one of the zones has a variable rate closing mode of operation which restricts flow at a constantly increasing rate as the condenser pressure rises.