Abstract: Apparatus for freezing liquid-carrying pipes, with an annular casing having an inwardly open cross-section, with a supply line, provided with a valve, for supplying a refrigerant to the interior of the casing, which is improved in that the casing (1) has two parts (2,3) which can be directly fixed together at right angles to the casing axis and with end walls (4,6;7,8) kept spaced by a jacket wall (9,11) and that a carbon dioxide supply lance (43) with its end face (44) having an opening can be brought up to the connecting face of the inside edges (41) of end walls (4,6;7,8).

Abstract: This is an improved beverage chiller which comprises a metallic preferably cylindrical shaped container preferably having a beveled mouth opening, a handle near the bottom end of the mouth opening, and a hook opposite to the handle as shown in the drawings. The container of the chiller is filled with fresh ice when its use is needed and it can be hung directly in the beverage fluid located in the container by means of its handle. This invention provides a "beverage chiller" without affecting the quality of the beverage itself, i.e., avoids dilution of the beverage from the melting ice that is placed directly into the beverage in conventional applications where beverage chilling is desired.

Abstract: Apparatus for cooling a semiconductor device by expansion cooling and/or evaporative cooling with a nontoxic gas includes a heat exchanger in thermal contact with the device to be cooled. A stream of expanding gas is released from a pressurized gas or liquid source through an expansion valve and is directed toward a heat exchange surface of the heat exchanger. The heat exchange surface includes fins which extend outwardly from the expansion valve and define grooves that direct the expanding gas over the heat exchange surface. The fins and grooves can be radial, spiral or branching for efficient thermal transfer. The grooves increase in cross-sectional area with radial distance from the expansion valve to accommodate the expanding gas volume. When a liquid is utilized, the liquid evaporates upon passing through the expansion valve, thereby providing both evaporative cooling and expansion cooling.

Abstract: A portable, hand held probe usable within a small confine to produce a point source of nitrogen or helium at a relatively constant temperature of 77 degrees Kelvin.

Abstract: A specially designed beverage container includes a centrally disposed conduit containing two separate reactants. The reactants are separated by a plastic membrane, and the membrane may be manually ruptured to effect a mixing of the reactants. The reactants, which comprise ammonium nitrate and distilled water, produce an endothermic reaction when mixed which in turn results in a rapid cooling of the beverage retained within the container.

Abstract: A cooling and insulating holder for a container such as a beverage can or the like has a plurality of hollow arcuate reservoir pieces which fit together to form a ring with a receiving opening therein to receive the container. A resilient sleeve surrounds the reservoir pieces and holds them in ring configuration. In this way, a container larger than the normal opening in the ring may be inserted into the opening and the reservoir pieces will separate against the force of the resilient sleeve. If the opening in the ring is equal to or slightly less in diameter than the smallest diameter container expected to be used with the device, the device will maintain that and larger containers snugly within the ring with good contact between the container and the inner reservoir walls. The reservoir pieces are each filled with a coolant material which, in use, is frozen prior to insertion of the container to be cooled.

Abstract: A discrete internal self-cooling device (106) installed in a standard beverage can (100) during assembly that operates, preferably, on the principle of heat loss through vaporization. A refrigerant vessel (112) is provided for holding a cryogenic refrigerant (114). The vessel includes a refrigerant vessel body (116) made up of cylindrical side walls with a cylinder vent hole (118) formed through it near the upper regrigerant vessel rim (120). The vessel sidewalls terminate in upper (122) and lower (128) plugs which seal the vessel. The upper plug (122) includes a regulated refrigerant escape rate means comprising a metering orifice (124) that extends through the plug axially. Intersecting this metering orifice, an automatic pressure actuated release means comprises a transverse plug cylinder (126) containing a pressure actuated piston (130) having a piston groove (134) that opens or closes the orifice, depending on its alignment with the orifice.

Abstract: An article for cooling a beverage includes a container of plastic material for containing a phase-change medium such as water. The cooling article is used by freezing the phase-change medium and immersing the article in the beverage. The article is preferably weighted to compensate for its positive buoyancy so that it is either generally suspended within the beverage or at the bottom of the beverage. Preferably, the article has projections thereon which increase its surface area, and the article may include internal metallic fins to increase the rate at which heat is transferred from the surface of the article to the interior thereof. If desired, the article may be configured to provide a secondary meaning, and it may include a phosphorescent medium so as to glow in areas of little or no light.

Abstract: A suction sound damper for a slide piston refrigerant compressor that includes a suction nipple that is pushable into a groove of a cylinder cover of the compressor when the nipple is in a predetermined position, and is seatable in sockets formed in two shells of a damper housing. The shells are sealed together after the nipple is seated in the sockets. The suction nipple is of a material having a higher thermal resistance than the shell material. The damper includes intermediate walls that together with the shells form four somewhat triangular chambers with a throttle opening from the first chamber to the second chamber, an elongated throttle passage from the second chamber to third chamber and a throttle opening from the third chamber to the fourth chamber. The suction nipple opens to the first chamber and each shell includes a part of an inlet that opens to the fourth chamber.

Abstract: A self-contained cooling device for cooling the contents of an open container includes a cooling portion which, upon activation of the device, is cooled below ambient temperature and a handle portion secured to the cooling portion but insulated therefrom so that a user can grasp the handle portion and insert the cooling portion into the contents of an open container to be cooled and manipulate the cooling portion in such contents. In a preferred embodiment of the device, the device takes the form of an elongate rod similar to a stir stick which can be inserted into ad stirred about the contents of a container to be cooled.

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.degree. F. to about 45.degree. F. in about 4 minutes.

Abstract: A therapeutic device for applying structures in direct contact with the skin of the human body to heat and to cool the same. A hot plate and a cool plate are provided on opposite sides of conventional electrical means to produce the heating and cooling. A plurality of vanes normal to the hot plate are fixed thereto and extend to an auxiliary plate to which they are also fixed. The vanes and the auxiliary plate aid in reducing the temperature of the hot plate and thereby aid in reducing the temperature of the cold plate. A fabric sock having differently weighted swatch portions for different thermal insulation surrounds the cold and auxiliary plates. A fan cools the vanes. A tray shaped body support is provided with holes to permit the escape of warm air produced by the fan.

Abstract: A method of holding an polishing a workpiece whereby a liquid such as water is applied between the workpiece and a support member and the liquid is frozen to secure the workpiece to the support member. A polishing member is positioned in contact with the workpiece in a grinding liquid and the polishing member and the workpiece are moved relative to each other to polish the workpiece. Grooves or through holes may be provided in a surface of the support member to hold the water or other suitable liquid. The liquid to be frozen further may be impregnated into a liquid absorbing material.

Abstract: A cryogenic extractor having a self-contained filler, and a tip activated by slanting the tip down. A cryogenic extractor has a foward chamber having a rod to be cooled, the rod extending adjacent to the top wall so the liquid will not reach the rod when the extractor is held horizontally with the bottom down. The extractor has a rear chamber for receiving the liquid refrigerant on filling. A filling cartridge is received in the rear chamber, and a base holds the cartridge. The base receives the skirt of the rear chamber on one step for shipping, and on another, lower step for use. The skirt must be forced over the lower step, and the fit holds the skirt in place and, provides a tight seal. An activator on the cartridge is pushed down when the extractor is pushed down, dispensing the refrigerant from the cartridge, and the refrigerant flows down into the rear chamber.

Abstract: A new instant cooling device for cosmetics is disclosed. Unique light weight and small refrigerator system is used in combination with a safety device to reinstate the proper hardness and consistency of facial cosmetics by cooling.The instant cooling device comprises pressure vessel with valve containing liquid refrigerant and adequate release mechanism to allow efficient cooling of personal size cosmetics.

Abstract: An article for cooling a beverage includes a container of plastic material for containing a phase-change medium such as water. The cooling article is used by freezing the phase-change medium and immersing the article in the beverage. The article is preferably weighted to compensate for its positive buoyancy so that it is either generally suspended within the beverage or at the bottom of the beverage. Preferably, the article has projections thereon which increase its surface area, and the article may include internal metallic fins to increase the rate at which heat is transferred from the surface of the article to the interior thereof. If desired, the article may be configured to provide a secondary meaning, and it may include a phosphorescent medium so as to glow in areas of little or no light.

Abstract: A cryostat microtome apparatus comprises a cooling enclosure which can be set to a predetermined internal temperature and a microtome disposed in the enclosure. The enclosure is supported on a support assembly which is vertically adjustable to permit stepless adjustment of the height of the enclosure, for adaptation to operator requirements. A mechanical actuating assembly and/or a gas spring assembly is provided for height adjustment of the apparatus.

Abstract: A thermoelectric cryoprobe comprising a handle composed of two electrically insulated halves made of a material possessing high heat conduction. One end of the handle is tapered, and a semiconductor cooling thermoelement is arranged at the butt of the tapered end. The height of the thermoelement does not exceed the radius thereof. The surface of a commutation plate of the thermoelement is the working surface of the thermoelectric cryoprobe.

Abstract: A flow stopping plug is formed in a conduit such as a fluid transmission pipeline by tapping a relatively small hole in the side of the pipe directly adjacent the desired location of the plug and inserting a flexible bag through the hole using a radially extendable bag insertion apparatus having a tube containing the bag initially in a collapsed or folded condition. The bag is connected to a conduit assembly which provides for filling the bag with water in the deployed position inside the pipe. After the bag is filled with water, a freezing process is carried out preferably using a cryogenic fluid which is circulated around the exterior of the pipe section directly adjacent to the bag. The conduit assembly connected to the bag may be placed in communication with a source of heating fluid for melting the ice plug formed within the bag after completion of the work process in connection with which the ice plug was deployed.

Abstract: A package for a cryogenically frozen liquid material which includes an enclosed flat pouch formed by two layers of a cryogenically durable, transparent, thermoplastic polymer film having heat-sealed inner edges with laminated fins extending outwardly along at least about 15% of the pouch periphery, the fins being extensions of the 2 film layers and having a heat-sealed area along their inner edges, and also at least in a marginal area adjacent their outermost peripheral edge. The invention also includes a protective supporting package to enclose and securely hold the pouch and its contents.

Abstract: Fluid transmission lines in a submarine or hazardous environment are provided with substantially fluid tight seals by the formation of a temporary ice plug within the interior of the line using a housing forming a cryogenic fluid circulation chamber installed around the exterior of the line. Remote controlled valves are interposed in separate conduits for supplying fluid to chambers formed within the housing, venting fluid vapor from the chambers, recirculating liquid cryogenic fluid back to a reservoir and for purging sea water from the chambers formed by the housing. The remote controlled valves are preferably controlled from a service vessel on the water surface or from within a submarine habitat. Conduit assemblies are provided with self closing quick disconnect connector assemblies whereby the service vessel containing a source of cryogenic fluid and a control station may abandon the work site during heavy sea conditions.

Abstract: An anesthetizer for dental treatment adapted to anesthetize the defective part of a tooth or gums by freezing. The anesthetizer comprises a hollow tubular anesthetizer body which is branched into a pair of branch tubes having ends opposing to each other with a suitable gap therebetween. A cap is detachably fitted around the end of each branch tube. The top of each cap is closed by a plate-type thermoelectric element with a colder surface directly outwardly. A connecting terminal is projected from the base end of each cap. Conductors for electrically energizing the thermoelectric element and conduits for supplying and discharging a fluid are extended through and sealed in the hollow anesthetizer body. In use, the cold side of the thermo-electric element is placed in contact with the outer surface of the defective part of the tooth or gums to freeze the same to a large depth to realize the anesthetized state without using any anesthetic agent.

Abstract: A tubular housing made up of a pair of sections forms a tubular inner compartment of a cross dimension larger than the outer diameter of a pipe in which water is to be frozen. The housing has opposite flanges arranged to be abutted together and bolt fasteners are provided in the flanges for releasably securing the housing sections together for installing and removing them laterally on a pipe. The end walls of the housing have openings arranged to fit around the pipe on which the housing is mounted and such openings have seals to provide a sealed engagement with the pipe. An inlet for freezing material extends into one side of the housing adjacent one end of the latter and an outlet for gas from the freezing material extends from the housing on the same side as the inlet and adjacent the other end of the housing. The two housing sections are symmetrically constructed whereby the inlet will be in one of the sections and the outlet will be in the other section.

Abstract: A flow stopping plug is formed in a conduit such as a fluid transmission pipeline by tapping a relatively small hole in the side of the pipe directly adjacent the desired location of the plug and inserting a flexible bag through the hole using a radially extendable bag insertion apparatus having a tube containing the bag initially in a collapsed or folded condition. The bag is connected to a conduit assembly which provides for filling the bag with water in the deployed position inside the pipe. After the bag is filled with water, a freezing process is carried out preferably using a cryogenic fluid which is circulated around the exterior of the pipe section directly adjacent to the bag. The conduit assembly connected to the bag may be placed in communication with a source of heating fluid for melting the ice plug formed within the bag after completion of the work process in connection with which the ice plug was deployed.

Abstract: Temporary plugs are formed in fluid transmission lines by circulating cryogenic fluid through a housing disposed on the exterior of the line to freeze a slug of liquid within the interior of the line. Flow of cryogenic fluid is controlled by sensing the temperature on the surface of the line and sensing the temperature in a housing vent line to indicate a predetermined maximum level of liquid. A temperature sensing and control apparatus is provided which includes dual temperature signal receiving and comparator circuits for operating control valves to open and close at minimum and maximum temperature set points. The control circuitry is operable to open and close the cryogenic fluid control valve in response to variation of the sensed temperature above or below the limit temperatures and in response to a change in temperature indicating an excess level of liquid cryogenic fluid in the chamber formed around the transmission line.

Abstract: An apparatus for facilitating assembling a length of flexible tubing on a component part which avoids the use of sealing solvents yet affords a secure placement of the tubing thereon. The apparatus and method assures a secure fitment by stretching the tubing to a predetermined dimension which is larger than the outside dimension of the portion on which the tubing is to be placed on the component part, and while in such a position the tubing is temporarily frozen by means of a coolant. An important feature in stretching the tubing to the enlarged dimension is in assuring that it is done in a uniform manner and that the stretched walls are substantially parallel to each other. This is effected by utilizing a parallel motion of jaw members which are placed within the tubing to stretch it to its expanded state.

Abstract: A cryogenic device and a method for selectively dispensing a jet of gas or a mixture of gas and liquid cryogen particles, that is, single phase or two phase fluid, at the user's option, from a nozzle selected from a range of nozzle sizes. Pressurized liquid cryogen is supplied through an orifice to a nozzle-equipped expansion chamber also connected to a pressure regulated source of gas. A valve-controlled passage venting to the atmosphere from the expansion chamber is normally closed but, when open, is effective to reduce the chamber pressure by a major fraction of 1 psig provided the gas flow from the pressurized gas source is interrupted. The single phase gas jet dispensed in the non-venting mode substantially instantly converts to a stable two phase jet of gas and liquid particles irrespective of which one of the nozzle sizes is then in use.

Abstract: Method for freezing a slug of water to form an ice plug in a section of a pipeline for hydrostatic testing purposes. The ice plug is formed by transferring thermal energy from the slug of water through the walls of the pipeline to a cryogenic cooling fluid such as liquid nitrogen. A section of the pipeline is filled with water and is enclosed by an insulated chamber. The chamber is filled with liquid nitrogen to form a pool around the pipeline. The liquid nitrogen is agitated by discharging a stream of nitrogen vapor through the pool. Heat exchange occurs as a result of heat transfer directly from the surface of the pipeline to the liquid nitrogen by the action of convection currents produced by the vigorous agitation of the liquid associated with the motion of the nitrogen vapor. In a preferred embodiment, the liquid nitrogen is diffused over the surface of the pipeline by means of a permeable layer of material which is easily wetted by the liquid nitrogen.

Abstract: An apparatus for refrigeration treatment is used in cryomedical treatment for applying gas of extremely low temperature onto an affected portion of a patient. In the flow system of the apparatus, there are a liquefied gas source, a temperature controlled bath and a conduit pipe having a cup at its end to be placed over the affected portion. The bath contains a liquid medium of high specific heat in which are immersed a mixing cylinder and an evaporator which are mutually connected with a plurality of tubes. The liquefied gas supplied from the source to the evaporator is vaporized and flowed through the tubes to the cylinder where the vaporized gas is mixed with a liquefied gas directly supplied from the source at an optimum gas temperature.

Abstract: An ice cube for use in beverages and which will not melt, so that it will not dilute the beverage, the ice cube being molded of transparent plastic so to resemble ice, and which can be frozen in a refrigerator freezer prior to use; and the ice cube in one design carrying an identifying numeral, which becomes less visible when the beverage and cube get less cold.

Abstract: A self contained freezing device for forming a plug of ice within a pipe section. A refrigeration unit supplies refrigerant to a cradle like freezer unit within which the section of pipe to be frozen is held in spaced relation to the inner face of the freezer. The space between the underside of the pipe and the inner face of the freezer is filled with water, for example by spraying. As the water freezes, in contact with the cradle like freezer unit, it covers the outer surface of the pipe section with an ice jacket. Alternatively, a bag of freezable jel may be substituted for the water spray and placed over the inside face of the freezer; and then the pipe section is placed within the fold of the bag. In the case of either alternative, the refrigerant is maintained inside the freezer, and out of contact with the pipe.

Abstract: Cold gas is used to freeze liquid in a pipe without directly encountering the pipe wall, which is surrounded and reinforced by a clamp assembly within a housing through which the gas flows. Gas temperature at an outlet from the housing is monitored for control of the rate of gas to provide a uniform cool down rate, avoiding thermal shock to the pipe.

Abstract: Apparatus for icing, freezing or frosting containers such as drinking glasses comprising a tank containing liquefied gas under pressure which is supplied through a valve and a coiled capillary conduit to a nozzle which sprays the liquefied gas into the interior of the drinking glass. A displaceable receiver plate is adapted for placement of the glass thereon and, in response to pressure applied to the glass, the receiver plate is displaced to open the valve which releases the liquefied gas from the tank into the coiled capillary conduit and, then, from the nozzle into the interior of the glass. The coil configuration of the capillary conduit provides resilience thereof and allows the same to undergo deformation as the receiver plate is displaced.

Abstract: A cryogenic device utilizing pressurized coolant gas and provided with a single control easily manipulatable by finger pressure to selectively furnish either continuous freezing or continuous thawing, each alone or in sequence. The expansion chamber is pressurized only when the control lever is deliberately held depressed and, in consequence, either the expansion chamber or the coolant inlet subassembly can be detached or exchanged without risk to the operator or the equipment and without need for closing off the coolant supply. A pressure regulator forming a part of the device limits the maximum possible pressure in the expansion chamber and exhaust passages to a safe value. The device is substantially noiseless in operation and the control is operable through first and second stages by movement in the same direction to provide freezing or warming modes at the user's option and is self-locking in the freezing mode but is automatically disengaged therefrom upon movement into the thawing mode.

Abstract: Apparatus for freezing a slug of liquid to form an ice plug in a section of a pipeline for hydrostatic testing purposes. The ice plug is formed by transferring thermal energy from the slug of liquid through the walls of the pipeline to a cryogenic cooling fluid such as liquid nitrogen. A section of the pipeline is filled with liquid and is enclosed by an insulated housing which defines a cooling chamber. The chamber is filled with liquid nitrogen to form a pool around the pipeline. The liquid nitrogen is agitated by discharging a stream of liquid nitrogen or nitrogen vapor through the pool. Heat exchange occurs as a result of sensible heat transfer directly from the surface of the pipeline to the pool of liquid nitrogen. In a preferred embodiment, the liquid nitrogen is discharged uniformly over the surface of the pipeline as the chamber is filled by means of an insulated header which forms a part of the chamber housing.

Abstract: A cryosurgical instrument which may be used with interchangeable spray and closed end cryotips includes a body member with a central bore extending partially therethrough. Refrigerant is supplied to a first point in the bore through a valved refrigerant supply line while an effluent opening connects an effluent line to a second point in the bore. The bore receives the inner ends of cryotips. All cryotips used with the instrument include refrigerant delivery tubes having inner ends which are positioned adjacent the first point in the bore and O-rings which are seated between the first point and the second point in the bore to prevent escape of refrigerant. Closed end cryotips to be used with the instrument further include an effluent channel extending from an expansion chamber to the second point in the bore. A second O-ring is provided with closed end cryotips.

Abstract: A cryosurgical instrument having a tip which is cooled by the Joule-Thomson expansion of a pressurized gas. The gas is conveyed to the tip by an inlet tube and exhausts through an exhaust tube connected to the rear of a fitting. The tip is connected to the forward portion of the fitting. The rear and forward portions of the fitting are rotatably connected by a bearing coupling which enables the tip to be rotated independent of the inlet and exhaust tubes.

Abstract: A cryogenic surgical apparatus using a Sterling-cycle refrigerator connected by elongate flexible conduits to a cryosurgical device having an operating probe. The refrigerator includes a compressor having first and second cylinders with pistons positioned therein. The cryosurgical device includes a housing defining an expansion cylinder. An expansion piston and seals are positioned within the cylinder in such manner that first and second distinct expansion spaces are defined between opposite ends of the piston and ends of the cylinder. The operating probe is connected to or positioned on the end of the housing closest to the first expansion space. A regenerator is positioned in the end of the expansion piston closest to the first expansion space and has an outlet communicating with the first expansion space and an inlet communicating with a space intermediate the two expansion spaces.

Abstract: An improved defrostable cryosurgical instrument has a unitary in-line valve assembly that permits the assembly to be contained right in the instrument itself without making the instrument unduly large, heavy or upsetting its balance. By a fingertip control right in the instrument itself, the valve assembly can be controlled to route refrigerant through the instrument's tip to operate the instrument in a freeze mode, a defrost mode and to turn the instrument off, while simultaneously depressurizing the tip.

Abstract: A combination straw and stirrer having an enlarged central section. The hollow structure is sealed by plugs at both ends to form a drink stirrer. When the plugs are removed the structure functions as a straw and the hollow structure may also be filled with water or other liquid and frozen to form a self-contained ice cooler.

Abstract: The subject invention relates to method and apparatus for controlling or manipulating a body of crude, refined, or used petroleum as, for example: in the herding and recovery of an oil spill in a body of water; in temporarily stopping a leak in an oil tanker caused by a cracked hull; in recovering oil inadvertantly spilled on a beach front; in plugging an oil casing pipe to control an oil fire at sea on a drilling platform; in effecting preliminary refinement of oil at the oil rig site; in transporting oil from the Arctic or Antarctic region without resorting to complicated and costly apparatus; and in many other applications. The method basically comprises exposing a body of crude, refined, or used petroleum mass either to a transient atmosphere or environment of a freezing, sub-freezing, or cryogenics temperature, or contacting the petroleum with a substance or mechanism exhibiting freezing, sub-freezing, or cryogenics temperatures.

Abstract: Apparatus for freezing a slug of water to form an ice plug in a section of a pipeline for hydrostatic testing purposes. The ice plug is formed by transferring thermal energy from the slug of water through the walls of the pipeline to a cryogenic cooling fluid such as liquid nitrogen. A section of the pipeline is filled with water and is enclosed by an insulated chamber. The chamber is filled with liquid nitrogen to form a pool around the pipeline. The liquid nitrogen is agitated by discharging a stream of nitrogen vapor through the pool. Heat exchange occurs as a result of heat transfer directly from the surface of the pipeline to the liquid nitrogen by the action of convection currents produced by the vigorous agitation of the liquid associated with the motion of the nitrogen vapor. In a preferred embodiment, the liquid nitrogen is diffused over the surface of the pipeline by means of a permeable layer of material which is easily wetted by the liquid nitrogen.

Abstract: An easily maintainable interface for magnet dewars which includes a low h leakage disconnect fitting that retains the vacuum integrity of both the dewar and the transfer line is provided. The fitting includes a bayonet-type insert having separate coils disposed about a central conduit for cooling or heating the unit depending upon intended use. Liquid helium is introduced axially through the bayonet which is adjustable to a purge position wherein either gaseous or liquid helium may be introduced to clean, heat or cool the unit, or a flow position wherein liquid helium is passed through the bayonet into the supply line.

Abstract: A cryogenic probe is disclosed comprising a barrel having a plunger mechanism movably mounted therein and having a valve on the lower end thereof. The valve normally closes the lower end of the barrel but the plunger may be moved relative to the barrel to permit cryogenic liquid such as liquid nitrogen to by-pass the valve and to move upwardly into the interior of the barrel. The valve has a tip portion at the lower end thereof. The barrel is removably positioned in a guard so that the tip portion extends outwardly through the bottom of the guard and so that the upper end of the plunger is exposed above the guard. The tip portion has a lower end portion which is extremely thin so that the cryogenic liquid will be positioned closely adjacent the skin but not in actual contact therewith when the tip portion is placed into contact with the patient's skin. The method of charging the device is disclosed as is the method of using the same.

Abstract: A stream bed sediment sampler easily obtains a nearly undisturbed, stratified sample containing stream gravel, intergravel water, and organic material. The temperature of a probe inserted into the sediment is quickly reduced to a point where the material immediately surrounding the probe freezes and clings to the probe upon its removal from the stream bed. The equipment is inexpensive, easy to assemble, and portable.

Abstract: A method of charging a cryogenic probe is disclosed comprising a barrel having a plunger mechanism movably mounted therein and having a valve on the lower end thereof. The valve normally closes the lower end of the barrel but the plunger may be moved relative to the barrel to permit cryogenic liquid such as liquid nitrogen to by-pass the valve and to move upwardly into the interior of the barrel. The valve has a tip portion at the lower end thereof. The barrel is removably positioned in a guard so that the tip portion extends outwardly through the bottom of the guard and so that the upper end of the plunger is exposed above the guard. The tip portion has a lower end portion which is extremely thin so that the cryogenic liquid will be positioned closely adjacent the skin but not in actual contact therewith when the tip portion is placed into contact with the patient's skin. The method of charging the device is disclosed as is the method of using the same.

Abstract: A cryosurgical instrument having a purge cycle of indeterminate duration, separate and apart from its cooling and warming modes, which can be conducted with a refrigerant consisting of a low pressure unsaturated or saturated gas. During the purge cycle, the pressure of the refrigerant gas is regulated to a level below that which is required to effect a Joule-Thomson expansion of the gas upon its entrance into an expansion chamber adjacent the tip of the instrument while simultaneously exhausting the effluent to the atmosphere through an exhaust valve actuated by a footswitch.

Abstract: A cryosurgical probe has a refrigerant supply conduit for conducting refrigerant to the hollow thermally-conductive probe tip. A refrigerant exhaust conduit extends through the probe into the tip and the end of the exhaust conduit in the tip is positioned a selected distance proximally of the end of the supply conduit. Thus, when refrigerant flows through the supply conduit to the tip, it tends to follow a flow path taking it more or less directly to the exhaust conduit. This creates a dead gas space inside the tip proximally of the end of the exhaust conduit, thereby minimizing direct cooling of portions of the probe adjacent to and proximally of the dead gas space and confining the freeze zone distal to that space. By adjusting the height of the exhaust conduit end proximally of the supply conduit end, the size of the freeze zone at the tip can be controlled. Further, if the probe has a defrost mode, defrost is enhanced because only the working end of the tip need be warmed.

Abstract: A small, disposable cryosurgical probe having a self-contained liquid refrigerant supply can be operated in either a freeze mode or a defrost mode. During the freeze mode the refrigerant is conducted from the supply to the probe tip as a two phase fluid so that the probe can freeze tissue for a relatively long period with a limited refrigerant supply. To facilitate detaching the probe tip from tissue, a button on the probe is depressed which switches the probe to its defrost mode of operation wherein room temperature liquid refrigerant is conducted directly from the supply to the probe tip thereby immediately warming the tip. The probe may be cycled several times between its freeze and defrost modes before the refrigerant supply is exhausted.

Abstract: There is disclosed a pressurized Freon cylinder having a cap including a threaded nipple with a puncturable end wall. Positioned within the nipple, by screwing into its internal threads, is a porous plastic filter in the path of the fluid as it leaves the container.