Showing papers on "Thermal expansion valve published in 1986"

Refrigerant flow control device

Abstract: In a refrigeration cycle in which the opening of the expansion valve is controlled by the super-heat degree of the refrigerant periodically detected at the outlet of the evaporator, a negative control signal is produced to rapidly change the opening of the expansion valve when the detected super-heat degree has reached zero. As a result, occurrence of the liquid back is prevented.

Regulating mechanism for the refrigerant flow to the evaporator or refrigerating systems or heat pumps and expansion valves arranged in the refrigerant flow

Abstract: An expansion valve (8), which is arranged between the condenser (2) and the evaporator (3) in the pump medium circulation system of the heat pump and is continuously controllable, is regulated as a function of set values by means of a computer (10), in particular, while taking into account the evaporator input temperature measured by means of sensing devices (5) and/or the evaporator output temperature measured by means of sensing devices (6). Because of the regulating by means of computers, the control is suitable for different heat pumps and/or conditions of use without structurally altering the expansion valve (8).

Air conditioning and heating unit for automotive vehicles

Abstract: An air conditioning and heating unit for automotive vehicles includes a blower, an evaporator and a heat exchanger disposed in a synthetic resin housing providing with integral air discharge outlets for the headroom, footroom and center plane of a passenger compartment and for windshield defrosting. The evaporator and the heat exchanger are arranged relative to one another so that the paths of the hot air and of the cold air from the blower to inlet openings of the various air discharge outlets are the same and so that the path of the hot air from the evaporator to the inlet openings is 1.3 to 1.8 times longer than the path of the cold air from the evaporator to the air outlet ducts. The inlet openings of the air outlet ducts emanate from a common chamber in the housing.

Portable quick chilling device

Abstract: The present invention is directed to a portable quick chilling device. A compressor is affixed to a base. A condenser is operatively connected to the compresser. A fan is provided for blowing air across the condenser. An accumulator is operatively connected to the condenser. A capillary tube (expansion valve) is operatively connected to the accumulator. The capillary tube is operatively connected to an evaporator. The evaporator is operatively connected to the compressor. The evaporator is a coil of tubing. Each ring of the coil is in contact with an adjacent ring. An inwardly facing surface of each ring is flattened. The capillary tube enters the coil where said evaporator is operatively connected to the compressor. The tube passes within the coil. The free end of the tube is bent to point back down the coil. The device cools a 12 ounce beverage can from about 75° F. to about 45° F. in about 4 minutes.

Refrigeration system having periodic flush cycles

Abstract: A microprocessor (200) controlled system for use in a refrigeration system which includes a plurality of pulse controlled solenoid flow control valves (38) suitable for use as expansion valves. A pulse width modulated control signal is generated for cyclically opening and closing the flow through the solenoid expansion valve (38). The duty cycle of the pulsed control signal determines the average flow rate through the valve (38). The microprocessor (200) controls, periodically, the opening of each expansion valve (38) to permit full flow therethrough to flush any accumulated compressor lubrication oil logged in any associated evaporator coils (214-215).

Air conditioner for vehicle

Abstract: PURPOSE:To facilitate the stepless adjustment of the air conditioning temperature by installing an autocooled type pulley in which revolution can be changed by pouring and discharging the working oil inside and controlling the pouring and discharge of the working oil according to the cooling faculty, in an air conditioner including a compressor which is driven by an engine. CONSTITUTION:An air conditioner for vehicle drives a compressor 3 through a belt transmission mechanism by the revolution of the driving shaft of an engine 1, and the compressed coolant gas is condensed in a condenser 4. After the liquid coolant is separated by a receiver 5 into gas and liquid, the gas is sent into an evaporator 7 through an expansion valve 6, and makes the heat exchange with the air blown by a blowing fan 8 changing it into the cold air, and the cold air is blown into a car room from a blow out-port. In this case, a pulley connected with the driving shaft of the engine 1 of the belt transmission mechanism is used as an autocooled type pulley in which revolution can be changed by pouring and discharging the working oil inside, and the number of revolution of the compressor 3 can be controlled by controlling the pouring and discharge of the working oil according to the cooling faculty.

Pulse controlled solenoid valve with food detection

Abstract: A flood detection means for use with a solenoid expansion valve in a refrigeration system is disclosed. The flood detection means responds to the temperature differential across the evaporator coil for throttling down the flow rate through the expansion valve when the temperature differential is less than a temperature threshold. When the temperature differential is greater than the threshold, the valve resumes normal operations from the throttled down condition.

Variable displacement refrigerant compressor of variable angle wobble plate type

Abstract: A variable displacement refrigerant compressor of the variable angle wobble or swash plate type is disclosed. The compressor according to the invention has a displacement control valve which is operable in response to the evaporator pressure so as to restrict the drop thereof by throttling the refrigerant gas flowing through a control port disposed between the evaporator and suction chamber. Crankcase of the compressor is arranged for direct communication with the evaporator so as to keep the crankcase under a pressure which is substantially the same as the evaporator pressure.

Automotive heater and air conditioner and process therefor

Abstract: An automotive heater and air conditioner in the form of a closed circuit reversible heat pump in which one internal heat exchanger accommodates both heating and cooling, selectively, and only a single set of ducts is required. Supplemental energy is provided in the system by using external heat exchanger means in close exchange proximity to and served by the waste heat of the automotive engine. The single exchanger selectively functions as evaporator and condenser. A reversible expansion valve functions between the external and inboard exchangers permitting selected conversion of the exchangers from a condenser to an evaporator function. Valving around the compressor permits selected directional control over refrigerant flow. The compressor can be selectively disconnected to turn off the heat pump. Air controllably ducted through, over and around the inboard exchanger is circulated into the passenger compartment to cool the occupants, to warm the occupants, and to defrost the windshield.

Refrigeration system with bypass valves

Abstract: The refrigeration system includes a refrigerant reservoir, a condenser bypass valve of the gas pressure diaphragm type and a diaphragm-type hot gas bypass valve for supplying hot gaseous refrigerant directly from the compressor or refrigerant receiver to the evaporator, bypassing the expansion valve. The bypass valves may be hermetically housed in the refrigerant reservor. The system is useful in a refrigerated gas separation apparatus such as a refrigerated dryer for compressed air, which includes a conditioner in the form of a shell and tube heat exchanger which cools incoming hot moist compressed air and warms outgoing cold dry air. The cooled moist gas is refrigerated by contact with a refrigeration system evaporator, in the form of a finned baffled coil, and the condensed moisture is removed in a moisture separator including a central conical baffle and peripheral longitudinal hooked scraper bars or baffles defining channels for collecting moisture and directing the liquid to a sump.

Integral evaporator and accumulator for air conditioning system

Abstract: An integral evaporator and accumulator for a motor vehicle air conditioning system formed with a stack of generally similarly configured plates and a pair of tanks.

Low-temperature refrigeration system

Abstract: A refrigeration system includes first and second refrigerant circuits each having a compressor, a condenser and an evaporator, each of the refrigerant circuits being charged with an organic refrigerant. The evaporator of the first refrigerant circuit is divided into a plurality of evaporator portions connected together in series. The condenser of the second refrigerant circuit is divided into condenser portions equal in number to the number of the evaporator portions of the first refrigerant circuit. The condenser portions of the second refrigerant circuit are paired with the evaporator portions of the first refrigerant circuit to provide heat exchangers. The refrigerant of the second refrigerant circuit is a mixture of refrigerants different in kind and in boiling point.

Refrigerator for car

Abstract: PURPOSE:To keep the inside of a refrigerator at low temperature for a long time by installing a cold accumulator for cooling frozen materials. CONSTITUTION:A refrigerator 1 for car is installed under a glove compartment 3. A cold accumulator 4 is arranged in the upper part of the refrigerator 1 and installed onto a heat insulating case 1a. Water as cold accumulating substance 6 is sealed into the cold accumulator 4, and an evaporator 7 is installed. Said evaporator 7 is constituted of pipes, and an expansion valve and a check valve etc. are installed. A cold keeping box 12 is installed under the case 1a, and the materials easily influenced by heat can be stored, in said box, and a means for detecting the degree of accumulation of cold may be installed in the cold accumulator 4 or a means for displaying the degree of accumulation of cold may be installed at a proper position. A circuit for controlling the coolant which flows into the evaporator 7 may be installed.

Heat pump with a reservoir storing higher pressure refrigerant of non-azeotropic mixture

Abstract: Disclosed is a heat pump comprising a main circuit containing a mixture of non-azeotropic refrigerants, the main circuit including a compressor for pressurizing the mixture, a first heat exchanger operating as a heat sink, a second heat exchanger operating as a heat source, and an expansion device connected between the first and second heat exchangers. A portion of the mixture is supplied through a first feed line from a first junction between the expansion valve and the first heat exchanger and vaporized before being fed to a rectifier where it coacts with liquid refrigerant to cause separation of higher pressure refrigerant of the mixture from the lower pressure refrigerant. The separated higher pressure refrigerant is stored in a reservoir in liquid phase and an overflowed portion of the liquid is returned to the rectifier as said coacting liquid. A second feed line couples a second junction between the expansion device and the second heat exchanger to a bottom portion of the rectifier to complete an auxiliary circuit. A bypass line is established from the bottom portion of reservoir to the second junction accordance with input power demand to control the operation of the rectifier.

Household refrigerator air flow system

Abstract: An air flow system for a refrigerator having a refrigeration system including a condenser, evaporator, compressor, and thermostatic control. A freezer compartment is located at the top of the refrigerator and a fresh food compartment is located below the freezer compartment with the compartments being separated by a partition. An area above the fresh food compartment contains the evaporator and a fan for circulating air through the evaporator, which fan cycles on when the compressor is operating and off when the compressor is not operating. The air flow system includes an air duct having an upper end to receive cold air from the evaporator and a lower end having an air flow control assembly located in the fresh food compartment for discharging cold air into the fresh food compartment. The lower end of the air duct has an upper wall with a downwardly projecting depending flange with a terminal end and a lower wall having an upwardly projecting depending flange with a terminal end, said terminal ends of the flanges being spaced from each other in the vertical plane. This structural arrangement reduces the amount of natural convection heat transfer that takes place between the evaporator area and fresh food compartment of the refrigerator when the evaporator fan is not operating.

Actuator means for the control of a refrigeration system expansion valve

Abstract: The invention relates to a valve assembly for a refrigeration system of the modulating kind used for controlling the flow of refrigerant through the evaporator. The difference between the inlet and outlet temperatures of the evaporator is utilized to control the superheat but the evaporator inlet temperature taken alone is utilized to set different ranges for the valve actuator temperature to accomodate different operating conditions.

Heat pump device

Abstract: PURPOSE:To secure the overheating temperature of suction gas in order to prevent the compression of liquid and reduce the oil temperature of a refrigerating machine to prevent the deterioration of the oil by a method wherein heat exchange is effected between the suction gas of a high-temperature heat pump and refrigerating machine oil in an oil separator or a compressor. CONSTITUTION:Refrigerant, compressed in a compressor 1, is separated in an oil separator 2 from refrigerating machine oil and, thereafter, is condensed in a condenser 3 and the pressure thereof is reduced by expansion in an expansion valve 4. Then, the refrigerant is evaporated in an evaporator 5 and, thereafter, heat exchange is effected between the high-temperature refrigerating oil, separated in the oil separator 2, then, is sucked into the compressor 1. Heat exchange is effected between gas, sucked into the compressor, and the high-temperature refrigerating oil in the oil separator 2 and, therefore, the degree of overheating of the gas may be secured and, simultaneously, the refrigerating machine oil may be cooled.

Valve arrangement for a variable displacement compressor

Abstract: A valve arrangement for a variable displacement refrigerant compressor comprising one or more valve assemblies adapted to regulate fluid communication between the compressor's discharge cavity and the interior of the crankcase as a function of a predetermined fluid pressure differential. The valve assemblies operate to modulate, as a function of the ambient temperature, the set point of the compressor thereby avoiding evaporator freeze up.

Air conditioning system in a motor vehicle

Abstract: In an air conditioning system in a motor vehicle with a water separator device arranged connected to an evaporator and with a flap upwardly optionally closing or releasing a bypass channel for a downstream heat exchanger, to reduce the overall size and to increase the water separation capacity, it is proposed to arrange the evaporator and the heat exchanger in an upright arrangement with a slight inclination with respect to the passenger compartment and at an approximately parallel distance from one another. In this arrangement, the heat exchanger has a vertical offset with respect to the evaporator, so that when the flap, designed as a baffle, is in the closed position, air flows under the heat exchanger and the air, as far as possible free of condensate, flows through the heat exchanger counter to the flow direction in the evaporator.

Pulse controlled solenoid valve with low ambient start-up means

Abstract: A refrigeration system including a solenoid actuated on-off modulated expansion valve and a controller for controlling the expansion valve is disclosed. The controller includes a low ambient start-up means responsive to the presence of liquid refrigerant at the inlet end of the expansion valve for overriding normal operations of the valve and maintaining the expansion valve open for refrigerant flow therethrough when liquid refrigerant is not present at the expansion valve. The low ambient start-up means includes temperature sensors upstream and downstream from the expansion valve to detect the temperature differential across the expansion valve. The temperature differential is compared to a threshold value and depending upon the comparison, either overrides the expansion valve to permit full flow therethrough or to allow the expansion valve to operate in response to the controller.

Refrigeration system with hot gas pre-cooler

Abstract: A refrigeration system is disclosed having greatly improved efficiency. The system includes a pre-cooler heat exchanger for sub-cooling the refrigerant hot gas from the compressor before entering the condenser to render the entire evaporator more effective for refrigeration purposes. The heat exchanger for pre-cooling the hot gas has one passage through which the hot gas flows and another passage, in heat exchange relation therewith, which is connected to receive a small flow of liquid refrigerant bled off from the main stream of the liquid refrigerant which refrigerant passes through an expansion valve or capillary tube to vaporize so that the refrigerant hot gas is sub-cooled by the latent heat of vaporization of the vaporizing refrigerant. This heat exchanger is located between the compressor and the condenser. The flow of the vaporized refrigerant used for cooling in the heat exchanger is connected to the return flow of vaporized refrigerant flowing from the evaporator to the compressor. This heat exchanger may be used alone or in combination with a direct expansion liquid refrigerant pre-cooler as disclosed in U.S. Pat. No. 4,577,468.

Device for controlling refrigeration cycle capacity

Abstract: In a refrigeration cycle in which a capacity-variable compressor a condenser, an expansion mechanism and an evaporator are connected in the order named, a device for controlling the capacity in the refrigeration cycle comprising a means for detecting the temperature of the compressor or the temperature of the gas discharged therefrom and a control device for limiting the maximum rotational speed of the compressor when the output from the means for detecting the temperature indicates a detected temperature lower than a predetermined level.

Low energy consumption air conditioning system

Abstract: A system for conditioning the air in a building which is inexpensive and economical to operate. The air is conditioned in three stages. First, the air passes through a water evaporator. Second, the air passes through a subterranean conduit to exchange heat with the ground. Third, the air passes through a refrigerant evaporator. A solar collector having reflectors to concentrate and direct the solar energy at a heat exchange coil is provided. A heat exchange oil is circulated through the coil. The refrigerant from the refrigerant evaporator passes through two stages of heat exchange. In the first stage, there is heat exchange with the water coming from the water evaporator. In the second stage, there is heat exchange with the oil coming from the solar collector.

The effect of short cycling and fan delay on the efficiency of a modified residential heat pump

Abstract: The object of this study was to determine if the use of a cycling controller would improve the efficiency of a residential air conditioner or heat pump Cyclic tests were performed on a capillary tube heat pump in three configurations: as manufactured, as modified to simulate a non-bleed expansion valve unit by operation of a valve in the liquid line, and as modified to simulate an air conditioner by elimination of the accumulator The two modifications, the liquid valve installation and accumulator removal, were found to greatly improve the cyclic performance to about equal levels; however, some cyclic losses remained It was concluded that any control strategy that resulted in shortened on-cycle run times would reduce cyclic efficiency for all designs tested It was further concluded, based in part on the work of others, that fan delay is an undesirable control strategy for units that have the indoor air handler and coil installed within the conditioned space

Method and device for gas conditioning

Abstract: Method and device for conditioning a gas such as air, wherein the gas is cooled by means of a cooling circuit for dehydration of the gas by evaporation of a refrigerant in the evaporator (16) of the cooling circuit. The gas is conducted also through a treatment zone in a regenerative exchanger apparatus, in which moisture is delivered to a moisture absorbing drying agent. The cooling circuit comprises in addition to the evaporator (16) a compressor (26) and a condenser (24). The cooling circuit is regulated as to its effect so that the greatest cooling and dehydration effect is obtained without any formation of ice on the evaporator taking place.

Method for regulating a refrigeration circuit process for a heat pump or a refrigerating machine and a heat pump or refrigerating machine for this

Abstract: In a refrigeration circuit process, in particular for a heat pump, it is envisaged that the condensate emerging from the condenser and the gaseous refrigerant emerging from the evaporator flow through an inner heat exchanger, in which the gaseous refrigerant is superheated and the condensate is subcooled. The evaporator and the condenser and in particular the inner heat exchanger are in this case designed in such a manner that the superheating takes place exclusively and the subcooling virtually exclusively in the inner heat exchanger. The superheating is kept so great that the temperature of the refrigerant after compression reaches a predetermined maximum value. To this end, the opening cross-section of an expansion valve is influenced depending on the temperature of the refrigerant after compression.

Heat pump type air conditioner

Abstract: PURPOSE:To lower discharge gas refrigerant temperature, to reduce heat loss in a discharge piping system and to improve space heating capacity by providing a reduced-diameter part for sucking part of liquid refrigerant through a liquid suction circuit in a discharge side refrigerant tube of a compressor, and sucking to mix the liquid refrigerant with high temperature gas refrigerant to be discharged from the compressor CONSTITUTION:Gas refrigerant to be discharged from a sealed compressor 1 at the time of space heating is guided to an indoor side heat exchanger 3 through a four-way valve 2, condensed therein to be converted to liquid refrigerant, and the condensing heat is radiated to a room to be conditioned, thereby space heating The liquid refrigerant is guided to an outdoor side heat exchanger 5 through an expansion valve 4, evaporated therein and then again sucked to the compressor 1 Extremely high temperature gas refrigerant to be discharged from the compressor 1 is accelerated at its flowing speed from a reduced-diameter part 6 in case of passing Accordingly, its dynamic pressure is increased, its static pressure is lowered, part of the liquid refrigerant output from the exchanger 3 is sucked through a suction pipe 8, and mixed with discharge gas refrigerant accelerated at its flowing speed through the part 6 Since the liquid refrigerant is at low temperature while the discharge gas refrigerant is at high temperature, the discharge gas refrigerant is cooled down to have an optimum temperature

Air conditioning unit for vehicle

Abstract: An air conditioning unit for cooling and dehumidifying a passenger room of a vehicle including a reciprocatory piston type refrigerant compressor having a refrigerant suction chamber, a compressed refrigerant discharge chamber, and an independent drive chamber for a drive mechanism to reciprocate compressor piston, a condenser, an expansion valve, an evaporator for thermal exchange, and an evaporating pressure control valve adjustably changing a fluid communication between the evaporator and the suction chamber of the compressor in response to a change is a cooling load. The air conditioning unit further includes a fluid bypass passageway providing a constant fluid communication between the evaporator and the drive chamber of the compressor regardless of the change in the cooling load so that a part of a lubricant containing refrigerant is always introduced into the drive chamber.

Refrigeration system including capacity modulation

Abstract: A refrigeration system adapted particularly for a vehicle air conditioning system and including a capacity modulation mechanism. A portion of the liquid refrigerant at the outlet of the condenser (18) is fed back to the suction chamber (106) of the compressor through the orifice (130) of a bypass valve (30). The valve is mounted on the compressor and is responsive to suction chamber pressure. As the evaporator temperature decreases, suction chamber pressure also decreases thereby opening the valve to meter a small amount of bypassed liquid refrigerant into the suction chamber of the compressor. A portion of the hot discharge gas may also be bypassed back into the suction chamber through the same valve (30) that meters the bypassed liquid refrigerant.