Abstract: A refrigerant flow amount control valve has a construction for adjusting the amount of flow of a refrigerant in a predetermined range and a bypass for allowing the refrigerant to flow without passing through the construction when the valve is in an open state. The construction and the bypass are disposed in parallel to form a common refrigerant flow path through the valve.

Abstract: An automotive air conditioner which conditions air making use of radiation of heat of a condenser and absorption of heat of an evaporator effectively. The evaporator 207 and the condenser 203 are disposed in a duct 100. An condenser disposed in a duct has a heat exchanging section in which heat exchange is performed between refrigerant and draft air. The heat exchanging section is divided into an upper stream area portion, a middle stream area portion and a lower stream area portion, and a temperature sensitive tube of a subcooling control valve is held in contact with a refrigerant passageway which interconnects the middle and lower stream area portions. The subcooling control valve adjusts the opening of a throttle portion thereof so that the subcooling degree on the upstream of the lower stream area portion where the temperature sensitive tube contacts may be a predetermined value (2.degree. to 10.degree. C.).

Abstract: An air conditioner including an outdoor unit containing a compressor and an outdoor heat exchanger therein, at least one indoor unit having both of an indoor heat exchanger and an electric expansion valve, and a pressure reducing member which is linked to the electric expansion valve in parallel in a refrigerant circuit and serves as resistance to refrigerant flowing therethrough. The valve opening degree of the electric expansion valve of the indoor unit when a room heating operation is stopped is set to be smaller than the valve opening degree of the electric expansion valve of the indoor unit when the room heating operation is conducted, and the resistance value of the pressure reducing member is set to be smaller than the resistance value to be provided to the refrigerant in accordance with the valve opening degree of the electric expansion valve when the room heating operation is stopped.

Abstract: An integral combination of expansion valve and evaporator in a cryostat using a single support member. The valve includes two flow orifices, one orifice being used primarily for steady-state operation and the other orifice being used only during cool-down. An actuator having a high coefficient of thermal expansion moves a needle positioned in the cool-down orifice such that a large orifice flow area at the start of cool-down is automatically and continuously reduced as the actuator temperature decreases as refrigerant is throttled through the orifice. Within a range of approximately 30 K from the desired steady-state evaporator temperature, the needle completely blocks the cool-down orifice. Then, refrigerant flows through the steady-state orifice which has a remotely adjustable needle. In the final stage of cool-down, the refrigerant system is entirely controlled by the steady-state orifice and its associated needle.

Abstract: A barrel-type refrigerator system and drain pan for use in refrigerating food products. The barrel-type refrigerator system includes an upper food compartment, middle coil-fan compartment, and a lower compressor compartment. The barrel-type refrigerator system works by using a forced cooled air system which will force cold air through an irregularly shaped refrigerator product zone and having the same air returned to the coil-fan compartment. The system will be set upon a system of caster wheels such that it may be moved to any location of a store by one individual.

Abstract: The present invention is directed to an integral bi-directional flow control valve. The valve includes a housing that defines a passageway for the flow of a fluid in a first direction and a second direction. The housing defines a phase change chamber in the passageway. A first restrictor having a first bore is positioned in the passageway adjacent the phase change chamber. The bore has a volume less than the volume of the chamber. As the fluid flows through the bore in the first direction into the chamber, the fluid changes from a liquid to a gas as it exits the bore. The gas continues to flow through the passageway. A second restrictor having a second bore is positioned in the passageway adjacent the chamber and opposed to the first restrictor. The second restrictor includes a second bore having a volume less than the volume of the chamber. The second bore can be the same size as the first bore or a different size depending on the application.

Abstract: A flow regulating valve for air conditioning systems is shown in which a body member (26, 26a-26e) is provided with a passageway (28, 28a-28f) which results in regulating flow of refrigerant into the evaporator of the air conditioning system under normal conditions. Under severe operating conditions, e.g., high ambient temperature and low or idle speeds, the system refrigerant pressure rises. This increases pressure in the evaporator and an increase in the saturation temperature of refrigerant in the evaporator. This increase in temperature is sensed by a thermostatic metal element (44, 80, 88) of the regulating valve which moves to increase restriction to the flow of the refrigerant fluid through the valve thereby decreasing pressure of the refrigerant entering the evaporator.

Abstract: An improved control system for air conditioners. The control system detects temperatures at various points in the air-conditioner, and determines the model numbers of an indoor and an outdoor sections of the air-conditioner from these temperature data and a set of given status data associated with the air-conditioner. The control system may periodically set optimum control parameters in accordance with the model numbers and current status data of the air-conditioner and, in response to the refrigerant temperature at the outlet of compressor of its heat exchanger, may control the flow rate of the refrigerant passing through a variable expansion valve, thereby providing optimum refrigerating capacity at all times.

Abstract: A microprocessor controlled system for use in a refrigeration system which includes a plurality of pulse controlled solenoid flow control valves suitable for use as expansion valves is disclosed. A pulse width modulated control signal is generated for cyclically opening and closing the flow through the solenoid expansion valve. The duty cycle of the pulsed control signal determines the average flow rate through the valve. The microprocessor responds to the flow rate through each of the solenoid valves to determine, on a system-wide basis, if each fixture in the system, as indicated by the flow rate through the expansion valve associated therewith, is operating properly.

Abstract: An environmental control system includes a refrigeration loop including a two-stage variable speed centrifugal compressor having a low pressure compressor in flow communication with a high pressure compressor and having an inlet and an outlet, a condenser having an inlet connected with the compressor outlet and an outlet, an evaporator having an inlet connected with the condenser outlet and an outlet connected with the compressor inlet and an expansion valve connected between the condenser outlet and the evaporator inlet, and a selectively operative bypass valve in flow communication with the low pressure compressor discharge and the compressor inlet for partially recirculating a portion of the low pressure compressor discharge back to the compressor inlet to regulate compressor flow balance.

Abstract: An air conditioner has a heating capacity which is increased with a compressor driven by an engine when an outdoor temperature is too low. A work load of the compressor is increased by injecting refrigerant into the compressor via an injecting port. As a result, a load of the engine is also increased so that a coolant temperature is also increased. A large heat radiation from the hot coolant to the indoor air is established at a coolant heat exchanger.

Abstract: A method and apparatus to refrigerate air in a compartment wherein liquid CO.sub.2 is delivered through a first primary heat exchanger such that sufficient heat is absorbed to evaporate the liquid carbon dioxide to form pressurized vapor. The pressurized vapor is heated in a gas fired heater to prevent solidification of the pressurized carbon dioxide when it is depressurized to provide isentropic expansion of the vapor through pneumatically driven fan motors into a secondary heat exchanger. Orifices in inlets to the fan motors and solenoid valves in flow lines to the fan motors keep the vapor pressurized while the heater supplies sufficient heat to prevent solidification when the CO.sub.2 vapor expands through the motors. CO.sub.2 vapor is routed from the second heat exchanger to chill surfaces in a dehumidifier to condense moisture from a stream of air before it flows to the heat exchangers.

Abstract: The microprocessor-based control system optimizes efficiency of the ON/OFF cycle by shutting the expansion valve fully closed at the beginning of each OFF cycle to maintain system pressure differential. At the beginning of each ON cycle the expansion valve is opened to an initial larger than average of three openings to allow the system to quickly reach steady state operating levels. Thereafter, the valve opening is reduced to an average of the last three steady state settings. After a predetermined time, control of the valve opening is passed to an adaptive control algorithm which adjusts the valve setting for optimized performance during steady state.

Abstract: A fluid flow circuit intended for use with heat pumps having a flow control valve comprising a pair of restrictor assemblies positioned in opposed relationship. The first restrictor assembly provides for restricted flow in a first direction and unrestricted flow in the opposed and second direction. The second restrictor assembly provides for restricted flow in the second direction and unrestricted flow in the first and opposed direction.

Abstract: A refrigerating circuit of an air conditioning apparatus has a refrigerating circuit which is formed with a compressor, an expansion valve, a first heat-exchanger and a second heat-exchanger. The amount of the refrigerant in the refrigerating circuit is controlled by the expansion valve which is controlled by a control unit. The control unit is provided with detector means including various sensors for detecting the ambient temperature, saturation temperature of the refrigerant in the refrigerating cycle, temperature of the discharged refrigerant fed from the compressor, etc. Detection of refrigerant leakage from the refrigerating circuit is accurately performed by the detector means. Control means responsive to the detector means controls the operation of the compressor. The compressor is stopped when the ambient temperature is within a pre-determined level and the discharged temperature exceeds a given level if the opening of the expansion valve is full. Malfunction of the compressor is thus prevented.

Abstract: There is disclosed a control system for controlling a refrigerating apparatus in which a control unit is arranged to calculate a super heat amount of a discharge gas of a compressor at the time immediately before starting operation of the compressor, on the basis of a difference between temperatures detected by a discharge gas temperature sensor and a condenser temperature sensor and to control an opening degree of an electronic expansion valve to a completely open state. After starting operation of the compressor, the control unit constantly measures the super heat amount of the discharge gas and controls the valve opening degree to the usual degree when the super heat amount becomes higher than the preset value.

Abstract: Disclosed is an air conditioner and, in particular, an air conditioner which is capable of blowing out warm air in heating mode. In the air conditioner of this invention, the condenser is thermally separated into an air-upstream-side and an air-downstream-side heat exchanger, and the heat exchange capacity of the air-downstream-side heat exchanger is adjusted, so that, under preset operating conditions, the entire refrigerant in the air-downstream-side heat exchanger can be kept in the superheated-gas phase, thus making it possible to blow out warm air having a temperature higher than the condensation temperature. Further, the refrigerant temperature at the outlet of the air-downstream-side heat exchanger is measured by a temperature sensor, and the revolving speed of the compressor, the revolving speed of the fan, etc., is so controlled that the temperature measured is kept at a level higher than the condensation temperature.

Abstract: A flow control valve is disclosed in a household refrigeration appliance having a vapor compression refrigeration system comprising a cyclically operated compressor, a condenser, an evaporator and an expansion device between the condenser and the evaporator. The refrigerant flow control valve is disposed between the condenser and the evaporator and comprises a housing defining a refrigerant flow chamber for receiving liquified refrigerant from the condenser outlet, valve seat structure defining a refrigerant flow port for communicating refrigerant from the condenser to the evaporator, and a flow controlling valve assembly coacting with the valve seat structure to control the refrigerant flow from the refrigerant flow chamber to the expansion device. The flow control valve controls system refrigerant flow in response to subcooling, blocks refrigerant flow from the condenser when the compressor is cycled off and enables circulation of hot gaseous refrigerant under extreme high temperature ambient conditions.

Abstract: Methods and apparatus for eliminating the need for a float valve in a flash tank of a refrigeration system having an economizer cycle, improving stationary refrigeration systems and permitting a flash tank instead of a heat exchanger to be used in a transport refrigeration system having an economizer cycle. The refrigeration system includes a refrigerant compressor, a condenser, and an evaporator, with the flash tank being disposed between the condenser and evaporator. A liquid sub-cooling valve is disposed between the condenser and flash tank. The liquid sub-cooling valve opens and closes to maintain a desired degree of sub-cooling, with the liquid sub-cooling valve thus controlling refrigerant flow into the flash tank. Refrigerant flow out of the flash tank to the evaporator is controlled by a suction superheat thermostatic expansion valve. In a preferred embodiment, liquid leaving the flash tank is sub-cooled before entering the expansion valve.

Abstract: A refrigerant flow metering device for use in a refrigeration system includes a body having a flow passage extending therethrough. A piston having a flow metering port extending therethrough is movably disposed within the flow passage. An elongated member extends into the metering port of the piston and cooperates with the port to define a flow metering passage therebetween. The elongated member is configured such that it will vary the cross-sectional area of the flow metering passage a function of the position of the member to the metering port. Means are provided for supporting the elongated member within the housing and for controlling the relative axial position of the elongated member and the piston with respect to one another as a function of the differential pressure across the piston. The refrigerant expansion device is capable of responding to certain pressure and flow conditions within a refrigeration system to provide optimum expansion areas within the device for such pressure and flow conditions.

Abstract: A cryogenic apparatus is described which is designed to be of a compact size and to provide multiple functions, including chilling of gas or liquid, condensation of condensible vapors, and separation of liquid and gas phases of liquified cryogenic gas. The level and/or temperature of cryogenic liquid in the apparatus is controlled by sensors. An inlet for liquified cryogenic gas and an inlet for fluid to be chilled or condensed pass through an upper closure and outlets for liquid cryogen and chilled or condensed fluid are provided in the lower wall of the vessel.

Abstract: A refrigeration cycle apparatus wherein a positive displacement type compressor is used as a cooling medium compressor, and part of a high-pressure liquid cooling medium liquefied in a condenser of a refrigeration cycle is introduced into a compression chamber of the compressor during a compression stroke thereof via first and second connecting pipes connected to the compressor, thereby preventing the overheating of the compressor. The position of connection of the first connecting pipe to the compressor is set to such a position of the compression chamber that when an operating pressure ratio requiring the cooling of the compressor is minimum, the pressure within the compression chamber of the compressor during the compression stroke can be below a condensation pressure at the operating pressure ratio.

Abstract: The expansion valve has an inlet connection fluidly connected to a main valve while the main valve is fluidly connected through an outlet connection to the inlet of the evaporator of a refrigeration system. The main valve has a housing that includes a main valve chamber and a valve seat for fluidly connecting the inlet connection to the main valve chamber and a valve member movable between an open position and blocking fluid flow through the valve seat from the inlet connection to the valve chamber. A pressure operated servo arrangement is disposed in the main valve chamber for controlling the movement of the valve element and opens to the pressure outlet of a pilot valve arrangement. The pilot valve arrangement is disposed in a branch path that opens to inlet connection and to the valve chamber downstream of the valve set for controlling the fluid pressure at the pressure outlet.

Abstract: A variable flow restrictor valve is disclosed that is adapted to be inserted in a fluid line to provide first and second alternative flow paths therethrough in accordance with the pressure differential between inlet and outlet ends of the valve. The assembly is characterized by use of a moveable orifice tube which defines one of the alternative paths and an intermediate part of a valve housing defines a flow path which forms another alternative flow path having flow therethrough regulated by a stop disk and a valve disk both of which are fixed to the orifice tube on either side of the intermediate part to position the valve disk to either close or open the another alternative flow path in accordance with the aforesaid pressure differential.

Abstract: A mechanical refrigerant expansion valve meters the flow of refrigerant therethrough in one direction through an orifice that varies in cross-sectional area as a function of the pressure differential across the valve. The same valve controls refrigerant flow in the other direction through a fixed area metering orifice.

Abstract: A flow metering device for use as an expansion valve in a heat pump system includes a body having a flow passage extending therethrough. Two pistons are moveably disposed within the flow passage. Each piston has a flow metering port extending therethrough and a bypass flow means associated therewith. A refrigerant metering rod is fixed within the flow passage and extends through both metering ports. The rod has two flow metering configurations formed thereupon, each of which cooperates with one of the pistons to define a variable area flow passage within the valve. The pistons are spring biased to closed positions when there is no flow through the valve. Flow in one direction results in metering through the variable area passage defined by one piston and its associated flow configuration and free flow through the bypass means of the other piston. Flow through the valve in the opposite direction reverses the roles of the pistons.

Abstract: A flow metering device for use as an expansion valve in a heat pump system includes a body having a flow passage extending therethrough. A piston having a flow metering port extending therethrough is moveably positioned within the flow passage. An elongated member extends through the metering port of the piston and is axially and radially fixed within the body. The elongated member has a central portion which cooperates with the metering port to prevent flow through the port when axially aligned with it. The elongated member has flow metering configurations formed thereon on both sides of the central portion. The piston is spring biased into alignment with the central portion. Refrigerant flow in either direction through the device results in movement of the piston against a spring force into a flow metering relationship with one of the metering configurations.

Abstract: A refrigerant expansion device for use in a refrigeration system includes a body having a flow passage extending therethrough. A piston having a flow metering port therethrough is moveably mounted within the flow passage. A flow metering rod is supported within the housing and extends through the flow metering port. The flow metering rod and the flow metering port cooperate to define a flow metering passage between them. The flow metering rod is configured so that the cross sectional area of the metering passage varies relative to the axial position of the piston with respect to the rod. The piston is spring biased and the piston moves relative to the rod as a function of the pressure differential across the piston.

Abstract: A fast response temperature probe, and method of manufacture, for use in the refrigerant line of a refrigeration system comprising: a temperature sensitive element; means for operably connecting the temperature sensitive element to a control line of a refrigeration system controller; an inner housing supporting the temperature sensitive element at a first end and enclosing the operable connection means; and an outer housing surrounding the temperature sensitive element and the inner housing, the outer housing including at least one aperture located in proximity to the temperature sensitive element.

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: In an automobile air conditioning system, an improved orifice type expansion device includes a movable piston which supports an orifice tube so that the piston is moved in response to higher than normal condenser pressure towards a stationary plug member so that the resistance to flow is increased and thus a desirable low evaporator pressure and temperature is maintained.

Abstract: An electrically actuated valve for incremental fluid flow rate control is disclosed. The valve is comprised of a valve body having an interior with a planar outlet surface against which a rectilinear valve element is slidingly operated. The valve body includes an inlet orifice and an outlet orifice in the planar outlet surface for fluid flow through the valve body. The valve element has an orifice therethrough controlling flow through the outlet orifice in accordance with the position of the valve element, which is linearly actuated by a rotary stepper motor.

Abstract: A refrigerating system for an ice making machine includes an external equalizer expansion valve having a pressure equalizing tube connected to an exit of an evaporator tube. A pressure adjusting pipe which becomes conductive only in deicing cycle is branched from the pressure equalizing tube and connected to the discharge side of a compressor. An on-off valve is installed in the pressure adjusting pipe and controllably communicated with a hot gas valve in a hot gas pipe so that both the valves are opened and closed simultaneously. Namely, when the hot gas valve is opened for carrying out the deicing cycle operation, the on-off valve of the pressure adjusting pipe is opened, while the expansion valve remains closed. In an ice making operation cycle during which the hot gas valve is closed, the on-off valve of the pressure adjusting pipe is also closed. Thus, the expansion valve is optimally opened and closed for adjusting the amount of the coolant supply.

Abstract: A method for improving cooling of a compressor element used in an air conditioning system and having a refrigerant compressor and associated drive motor hermetically sealed in a fluid-tight shell includes the steps of detecting an excessive increase in the temperature of the compressor element, intermittently operating the system during the excessive temperature detection with a superheat of a refrigerant in the system below zero superheat degrees to concurrently allow liquid refrigerant to enter the shell to enhance the cooling of the compressor apparatus by the latent heat of vaporization of the liquid refrigerant and terminating the intermittent operation and the admittance of the liquid refrigerant into the compressor element upon a detection of a desired temperature of operation of the compressor element.

Abstract: A method for minimizing or eliminating the audible flow noise which accompanies the short initial period of compressor operation in an air-conditioning or refrigeration system which system utilizes an electrically-actuated expansion valve. The method is comprised of two steps used singly or in combination, said steps being (a) maintaining said valve in a closed or non-operative mode for a short period of time after the compressor is energized; and, (b) pulsing said valve at a higher-than-normal frequency for a short period of time commencing when the compressor is energized or shortly thereafter.

Abstract: An improved control device for a refrigeration circuit including a tubular casing having three spaced walls on its interior surface is disclosed. The first wall is a plurality of holes, the second wall has a longitudinal bore with a valve seat facing the first wall and the third wall includes at least one hole. A first bellows is attached to the inner surface of the first wall in the region between the first and second walls and has a valve element at its other end. The valve element includes a spherical sealing element which fits within the valve seat to control the flow of refrigerant through the longitudinal bore. A second bellows is attached to the interior surface of the third wall and has a valve control element extending from its other end into the longidudinal bore. When the level of refrigerant is below a predetermined level, the first bellows expands and the spherical sealing element contacts the valve seat preventing fluid flow through the longitudinal bore.

Abstract: A refrigeration circuit including a compressor, a condenser, a control device, an evaporator and an accumulator is disclosed. The elements are serially arranged with the control device located between the outlet of the condenser and the inlet of the evaporator. The control device includes a tubular casing having three spaced walls on its interior surface. The first wall includes a plurality of holes and has a bellows attached to the interior surface thereof, the second wall has a longitudinal bore and a parallel bypass hole therethrough, and the third wall includes an orifice. An operating valve is mounted on the opposite end of the bellows. The bellows expands and contracts in accordance with the temperature of refrigerant fluid and the outlet side of the condenser, thereby, moving the operating valve to the left or the right. Movement of the operating valve controls the open cross-sectional area of the longitudinal bore so that the flow volume of refrigerant fluid in the circuit may be controlled.

Abstract: A refrigerant flow control system associated with a refrigerant circulating circuit having a compressor, a condenser, an expansion valve and an evaporator, includes a branch pipe extending from a discharge pipe of the compressor and having on sealed free end. A first temperature sensor is disposed on the branch pipe near the sealed free end for detecting a condensation temperature of a refrigerant which is condensed in the branch pipe. A second temperature sensor is disposed on the discharge pipe of the compressor for detecting a temperature of the gaseous refrigerant discharged from the compressor. The signals representative of the condensation temperature and the temperature of the discharge gaseous refrigerant are inputted to a control device.

Abstract: An apparatus for controlling the opening and closing operation of a liquid flow valve dispensing fluid fed thereto from a reservoir, using the inherent gas pressure from the reservoir, comprising in combination (a) an actuator means operably connected to the flow valve for opening and closing the same; and (b) control means for controlling the operation of the actuator means, the control means comprising circuitry having pneumatic linear timer means and pneumatic control valve means operably connected one to another and to the actuator means. Also disclosed is a method of controlling the opening and/or closing operation of a liquid flow valve dispensing liquid fed thereto from a reservoir, using the inherent gas pressure from the reservoir.

Abstract: In a method of controlling a refrigeration cycle constructed by connecting a compressor, an outdoor-side heat exchanger, an expansion valve, and an indoor-side heat exchanger, the temperature of a coolant ejected from the compressor is detected by a sensor, and the opening rate of the valve is adjusted in accordance with the detected temperature. When the detected temperature exceeds a prescribed upper limit, that opening rate of the valve which is indicated on that occasion is stored in a memory, and then the opening rate of the valve is increased to reduce the temperature of the ejected coolant to a lower level than a prescribed lower limit. After the temperature decreases from the lower limit, the opening rate of the valve is adjusted to a larger level than that level which is previously stored in a memory by a prescribed extent, thereby keeping the temperature of the ejected coolant between the upper and lower limits.

Abstract: A control apparatus and method is provided for controlling temperatures, temperature differences, or, respectively, liquid levels in refrigeration cycles used for example in heat pumps or refrigeration installations, which is not dependent on the refrigerating medium employed or on the field of application. The flow of the liquid is controlled by two position relay control valves which are electromagnetically actuated and operated by fluid pressure, are suited for large numbers of cycles and are wear resistant. Instabilities in the refrigeration medium cycle are avoided and variations in the end point of the evaporation no longer have a negative influence on the functioning of the control system. The conventionally employed thermostatic expansion valves are replaced by wear resistant two position valves with high frequencies of switching.

Abstract: Controller for a cooling system utilizing the Joule-Thomson effect for a cryostat, wherein the expansible component consists of a metal rod (20) of very small diameter, inside and coaxial with the tubular envelope (7), one end (21) of this rod (20) is fixed mechanically, and is joined thermally by a transverse bulkhead (22), to the tubular envelope (7) at a point of the latter lying between the warm point and the cold point (10), the other end (23) of this rod is fixed to a fork (16) for operating the needle (13) surrounding the seat (11,12) of the needle and driving the needle (13) through the intermediary of an adjustment component (18), and lastly the said fork (16) incorporates a periphery, preferably cylindrical, which leaves a large annular gap between this periphery and the inside surface of the envelope tube (7).

Abstract: A heat pump employing a capillary tube as an expansion device is disclosed. The main throttle portion of the heat pump comprises a main capillary tube and a by-pass through which a portion of the refrigerant flows and cools the refrigerant flowing through the main capillary tube. A solenoid valve for controlling the flow of refrigerant through the main capillary tube is connected to the intake of the main capillary tube, and an electrical expansion valve is connected to the intake of the by-pass for controlling the flow therethrough. An auxiliary capillary tube for cooling and an auxiliary capillary tube for heating are connected in parallel with the main throttle portion, both capillary tubes having a higher resistance to flow than the main capillary tube.

Abstract: The region 1 to be cooled contains the evaporator of a heat pipe 2 which contains a diphase fluid adapted to the desired temperature between about 0.degree. and -100.degree. C. The condenser 7 of the heat pipe is cooled to a set temperature by a copper ring 8 which is cooled by a regulated liquid nitrogen current. Applications in the freeze trapping of solvents contained in a gaseous current.

Abstract: An incrementally adjustable electronic expansion valve for precisely controlling refrigerant flow through the valve is disclosed. Basically, the expansion valve includes a stepper motor, a sleeve member, and an orifice assembly. The sleeve member is incrementally moved over a slot(s) in the orifice assembly by operation of the stepper motor to control refrigerant flow between an inlet and an outlet of an expansion valve. A control system provides electronic digital control signals to the stepper motor to control operation of the motor in response to superheat of refrigerant flowing from an evaporator to a compressor of the refrigeration system. The electronic expansion valve may also include sealing means to substantially prevent refrigerant flow through the valve when the sleeve member is in its fully closed position.

Abstract: A control for use with an expendable refrigeration system is disclosed which has particular use in refrigerated transport applications. The control is used to regulate the injection of refrigerant into the space to be refrigerated and provides an accurate means of precisely selecting a preferred ratio of "on" to "off" timing segments in each cycle and the number of complete cycles in a given time frame. In one embodiment of the invention, pneumatic pressures are used to power an oscillating device, the number of oscillations are counted to a selectable total. Attainment of the chosen total causes the counter to transmit a signal, which signal actuates the operator of a four-way valve. The switching of the valve provides the means to (a) open a liquid line valve to inject the refrigerant into the refrigerated space and (b) reset the counter, terminate the actuation signal and start the next cycle count.

Abstract: In a refrigerating system comprising a compressor, a condenser, a capillary tube, and an evaporator, there are provided a check valve on an inlet side of the condenser for preventing a reverse flow of refrigerant from the condenser to the compressor, and a differential valve connected to a delivery side of the condenser. One port of the differential valve is connected with the delivery side of the compressor, so that the differential valve interrupts the flow of the refrigerant from the condenser to the capillary tube upon interruption of the operation of the compressor thereby to improve the operational efficiency of the refrigerating system when the system is started again.

Abstract: In a heat pump type air conditioning apparatus of the type wherein a variable capacity type compressor is connected with a conduit including an outdoor heat exchanger, a first capillary tube and an indoor heat exchanger via a four way valve, there are provided a bridge circuit connected between the first capillary tube and the indoor heat exchanger, the bridge circuit being constituted by a first conduit including a first check valve permitting a flow of the refrigerant at the time of cooling and a second capillary tube, and a second conduit connected in parallel with the first conduit and including a second check valve permitting a flow of the refrigerant at the time of heating and a third capillary tube, and a bypass conduit including a controlled valve and connected between the first and second conduits, a cooling conduit for the compressor and connected to the control valve, and a control circuit for controlling the controlled valve in accordance with the temperature of the refrigerant discharged from the

Abstract: This invention relates to apparatus for temporarily rendering rigid a product of soft material of elongated form such as a rubber tube. In this apparatus, a tube of the product penetrates into a tunnel and issues therefrom after having been cooled by liquid nitrogen vaporized in an exchanger. A part of the nitrogen travels in counterflow and another predetermined part thereof travels in equidirectional flow towards a processing station.The invention is particularly applicable to braiding or winding rubber tubes, but is not limited to this field of use.

Abstract: A system for producing refrigeration from a source of liquid carbon dioxide. The liquid carbon dioxide is injected through a nozzle into a primary stream within an elongate enclosure. The enclosure is mounted with its inlet end spaced about the nozzle to define an opening through which an annular stream of ambient gas is directed about the primary stream. The ambient gas turbulently intermixes with the injected coolant for subliming any solid carbon dioxide or snow so that the resulting stream exhausting from the enclosure is free of snow.