General Electric Company

Heinz Jaster

Warren F Bessler

Curtis Alan Johnson

Edward Brittain Stokes

D Sangeeta

Himanshu B Vakil

Richard Roy Worthing, Jr

Howard John Farr

Fred W Staub

Keith Humphries Betscher

Thomas J Cartier, Jr

Alexander S Allen

William J Ward, Iii

James Alfred Day

Russell Scott Miller

David Joseph Najewicz

Philip G Kosky

LeRoy J Herbst

Gregg W Frey

Frank Joseph Bowden

Jin-Koo Park

Method for stripping ceramic coatings from the surfaces of articles. The apparatus includes a dedicated pressure vessel, such as an autoclave, which is maintained at an elevated temperature. Caustic solution is preheated to a first elevated temperature before injecting it into the autoclave, and the caustic solution is filtered and cooled after use in the autoclave. The articles are stripped of coating by maintaining the articles at an elevated temperature and pressure for a predetermined time. Various options include the use of analytical equipment to maintain the chemistry of the caustic solution and use of a volatile organic solution to prepressurize the autoclave and shorten cycle time. The articles are transferred to a separate pressure vessel after completion of the stripping operation so that the autoclave used for stripping can be maintained at an elevated temperature, thereby shortening the cycle time for stripping of additional articles.

Method for removing ceramic coatings from component surfaces

Analysis equipment for determining a concentration of an organic component and a caustic component of a reusable organic caustic solution that has been utilized for removing a ceramic coating from a metallic component at elevated temperatures and pressures, such as in an autoclave. Sensors are positioned between a filter for removing particles of the ceramic coating dispersed in the reusable organic caustic solution from the reusable organic caustic solution and a storage tank storing the reusable organic caustic solution after removal from the autoclave. The sensors measure physical properties of the reusable organic caustic solution after removal of the particles from the reusable organic caustic solution, such as electrical conductivity, opacity, refractive index, density, fluidity and the speed of sound in the solution.

Analysis equipment for determining physical properties of an organic solution

Apparatus for stripping ceramic coatings from the surfaces of articles. The apparatus includes a dedicated pressure vessel, such as an autoclave, which is maintained at an elevated temperature. Caustic solution is preheated to a first elevated temperature before injecting it into the autoclave, and the caustic solution is filtered and cooled after use in the autoclave. The articles are stripped of coating by maintaining the articles at an elevated temperature and pressure for a predetermined time. Various options include the use of analytical equipment to maintain the chemistry of the caustic solution and use of a volatile organic solution to prepressurize the autoclave and shorten cycle time. The autoclave is maintained in a nitrogen chamber to minimize the risks associated with volatile components. The articles are transferred to a separate pressure vessel after completion of the stripping operation so that the autoclave used for stripping can be maintained at an elevated temperature, thereby shortening the cycle time for stripping of additional articles.

Apparatus and process to clean and strip coatings from hardware

A refrigeration system is disposed within a refrigerator having a freezer compartment and a refrigeration compartment. The refrigeration system includes an evaporator having an inlet and an outlet. A damper is positioned so as to direct air flow into the freezer compartment or the refrigeration compartment and correspondingly block air flow to the other. A compressor is coupled to the evaporator via a conduit and a control valve is coupled to the inlet of the evaporator to control flow of refrigerant. A condenser is coupled to the control valve by a liquid line. A first temperature sensor is positioned so as to detect refrigerant temperature within the evaporator and a second temperature sensor is positioned so as to detect refrigerant temperature at the outlet of the evaporator. A first controller is coupled to the control valve and to the first and second temperature sensors to receive temperature signals therefrom. A second controller is coupled to the compressor to provide compressor signals thereto and to the damper to send damper signals thereto. The first controller controls the duty cycle of the control valve.

Refrigeration expansion control

A refrigeration system includes a compressor, a condenser, an expansion throttle, an evaporator and a control valve. All of the above elements are connected in series, in that order, in a refrigerant flow relationship. During periods in which the compressor initiates a passive defrost mode, control valve disposed within the conduit connecting the compressor and the evaporator remains open. Liquid refrigerant, by force of gravity, drains from the bottom of evaporator through the conduit to the compressor. This draining liquid refrigerant is evaporated by the hot compressor, flowing upward to the cold evaporator surfaces and condensing. The condensation releases latent heat of vaporization and heats the surface of the evaporator melting ice buildup thereon. In another embodiment, the refrigeration system further includes a bypass line connecting the compressor to the top of the evaporator. The inclusion of the bypass line allows the flow of the evaporated refrigerant to flow directly from the compressor to the evaporator through the bypass line, and the flow of liquid refrigerant to flow directly from the evaporator to the compressor through the conduit, such that no counter-current liquid and vapor flow within one conduit is required.

Refrigeration passive defrost system

A refrigeration system includes a phase separator disposed in flow communication with a pulse width modulated solenoid valve. A thermistor is disposed in the phase separator and is submerged in either refrigerant liquid or refrigerant vapor during operation, with the electrical resistance thereof correspondingly changing. In an exemplary embodiment, a second thermistor is used in conjunction with the first thermistor and is disposed in the vapor inside the phase separator to provide a reference. By comparing voltage developed across the two thermistors during operation it may be determined whether one or both of the thermistors are submersed in the vapor. The duty cycle of the valve may therefore be increased when one of the thermistors is submerged in the liquid, and decreased when both thermistors are submersed in the vapor.

Refrigerant level control in a refrigeration system

A device for improving heat dissipation inside an ultrasound probe and reducing heat build-up near the transducer face. Heat conductors are placed around the periphery of the transducer package, but within the probe housing, so that heat can be drawn away from the transducer face and toward the rear/interior of the probe. The heat conductors act as conduits for draining away heat which builds up in the thermal potting material during pulsation of the piezoelectric transducer elements. The heat conductors are formed from metal foil having a heat conductivity greater than the heat conductivity of the thermal potting material which fills the spaces inside the probe housing and surrounds the transducer package. The preferred metal foil is aluminum.

Method and apparatus for dissipating heat from a transducer element

Pulse width modulation is used to control the flow rate through a solenoid expansion valve in a refrigeration system using a simple vapor compression cycle. The refrigeration cycle includes a phase separator which receives two phase refrigerant from the condenser and supplies liquid refrigerant to the pulse width modulated solenoid valve. A liquid level sensor is disposed in the phase separator, and a controller for controlling the duty cycle of the pulse width modulated solenoid valve is provided to receive input from the liquid level sensor. The liquid level sensor can be of the type which provides a continuously variable signal as a function of liquid level, or it can be a liquid level switch which controls valve duty cycle on the basis of whether the phase separator liquid level is above or below a set level. Alternatively, two liquid level switches can be provided.

Refrigerant flow rate control based on liquid level in simple vapor

Pulse width modulation is used to control the flow rate through a solenoid expansion valve in a refrigeration system using a dual evaporator, two-stage cycle. The refrigeration cycle includes a phase separator which receives two phase refrigerant from the low temperature evaporator and supplies liquid refrigerant to the pulse width modulated solenoid valve. A liquid level sensor is disposed in the phase separator, and a controller for controlling the duty cycle of the pulse width modulated solenoid valve is provided to receive input from the liquid level sensor. The liquid level sensor can be of the type which provides a continuously variable signal as a function of liquid level, or it can be a liquid level switch which controls valve duty cycle on the basis of whether the phase separator liquid level is above or below a set level. Alternatively, two liquid level switches can be provided.

Refrigerant flow rate control based on liquid level in dual evaporator

Low thermal conductivity insulation for refrigerators and the like is produced by blowing a resinous foam in an inert (e.g., nitrogen) atmosphere with a mixture of carbon dioxide and a low thermal conductivity inert gas such as krypton or xenon. The foam is then sealed in a gas-impervious enclosure and carbon dioxide is removed therefrom, typically by inclusion in said enclosure of a solid material reacted therewith such as an alkaline reagent. The final partial pressure of the low thermal conductivity gas in the enclosure is in the range of about 20-200 torr, and the total pressure is up to 110% of said partial pressure.

Insulating foam of low thermal conductivity and method of preparation

A refrigerator evaporator is formed in a spread serpentine configuration having a plurality of straight tube segments and a plurality of bent tube segments where each one of the straight tube segments is joined at an acute angle to at least one other straight tube segment. The straight tube segments are arranged in a number of planar rows which are adjacent and parallel to one another. Approximately 25-50 percent of the cross-sectional area of the evaporator is not occupied by tubing or any attached fins. A cross flow blower disposed at one end of the evaporator draws air longitudinally over the evaporator.

Spread serpentine refrigerator evaporator

A refrigerant flow control unit for a refrigeration system, particularly a refrigeration system having a compressor, a condenser connected to receive refrigerant discharged from the compressor, and a plurality of evaporators. A first one of the evaporators is connected to receive at least a portion of the refrigerant discharged from the condenser and the remaining evaporators are connected to receive at least a portion of the refrigerant discharged from another evaporator. The refrigerant flow control unit is connected to receive at least a portion of the refrigerant discharged from each one of the evaporators. The refrigerant flow control unit is also connected to the compressor and is repeatedly operable to alternately connect one of the evaporators respectively in exclusive refrigerant flow relationship with the compressor. In one preferred embodiment, the refrigerant flow control unit is operated in accordance with measurable physical attributes of one or more of the evaporators, such as pressure, temperature, density of mass flow rate.

Refrigeration system and refrigerant flow control apparatus therefor

A refrigerator apparatus is provided having a cabinet with a freezer compartment and a fresh food compartment. The compartments define two passageways allowing air circulation therebetween. A refrigerator system is included having a compressor, a condenser, an expansion valve, an evaporator situated in the freezer compartment. The refrigerator system elements are connected in series in a closed loop, in a refrigerant flow relationship. A first fan is situated in the freezer compartment for providing air flow over the evaporator. A second fan is situated in one of the two passageways for providing air circulation between the two compartments. A first thermostatic controller situated in the freezer compartment for maintaining a desired temperature in the freezer compartment by causing the compressor and the first fan to operate. A second thermostatic controller situated in the fresh food compartment for maintaining a desired temperature in the fresh food compartment by causing operation of the second fan circulating air between the compartments thereby cooling the fresh food compartment.

Apparatus for controlling a dual evaporator, dual fan refrigerator with

A heat transfer arrangement for a refrigeration circuit is described. In one embodiment and for a refrigeration circuit including compressor means, a plurality of evaporator means coupled to the compressor means, one of the evaporator means being arranged to operate at a temperature lower than the operating temperature of the other evaporator means, the present heat transfer arrangement comprises a first conduit means coupled to the outlet of the one evaporator means, the first conduit means being at least partially disposed in a heat transfer arrangement with at least a portion of a second conduit means coupled to the inlet of the one evaporator means.

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Schenectady, NY, United States of America

Heinz Jaster