There is provided a connection device for connecting a first depressurization vessel to a second depressurization vessel. The connection device includes a communication hole comprising a first opening which is connected to the first depressurization vessel, and a second opening which is connected to the second depressurization vessel, the first opening and the second opening being, respectively, at opposite ends of the communication hole such that extreme ultraviolet radiation passes in a radiation direction from the first opening to the second opening; a gas inlet through which a gas flows into the communication hole in a direction perpendicular to the radiation direction of the extreme ultraviolet radiation; and a gas outlet which is opposed to the gas inlet such that the gas passes out the gas outlet.

1. Technical Field
Devices and apparatuses consistent with the present disclosure relate to extreme ultraviolet radiation and, more particularly, to a connection device provided between an extreme ultraviolet radiation source and an extreme ultraviolet radiation receiving device.
2. Related Art
FIG. 7 shows an example of a configuration of a related-art connection device between an extreme ultraviolet radiation source (hereinafter, referred to as an "EUV radiation source") and a chamber containing an exposure tool. FIG. 7 is a cross-sectional view taken along an optical axis.
The EUV radiation source has a chamber 10 as a discharge vessel. The chamber 10 of the EUV radiation source includes a first chamber 10a and a second chamber 10b. The first chamber 10a is provided with a discharge portion 1 for heating and exciting an EUV radiating species. The second chamber 10b is provided with an EUV collector mirror 2 for collecting EUV radiation. The EUV radiation is emitted from high temperature plasma generated from the EUV radiating species heated and excited by the discharge portion 1.
The EUV collector mirror 2 collects the EUV radiation, and guides the EUV radiation from an EUV radiation output portion 4 of the second chamber 10b to an irradiation optical system including an exposure tool (not shown).
The first chamber 10a is connected to exhaust unit 9c. The second chamber 10b is connected to a first gas supply unit 16a and a second gas supply unit 16b for supplying cleaning gas or the like and also is connected to a first gas exhaust unit 9a and a second gas exhaust unit 9b. The insides of the chambers 10a and 10b are depressurized by the gas exhaust units 9a, 9b, and 9c.
In the discharge portion 1, a first discharge electrode 11 as a disk-shaped member made of metal and a second discharge electrode 12 as a disk-shaped member made of metal are disposed with an insulator 13 interposed therebetween.
The center of the first discharge electrode 11 and the center of the second discharge electrode 12 are substantially on the same axis, and the first discharge electrode 11 and the second discharge electrode 12 are fixed at positions away from each other by a thickness of the insulator 13. A diameter of the second discharge electrode 12 is larger than that of the first discharge electrode 11. The thickness of the insulator 13, that is, a distance between the first discharge electrode 11 and the second discharge electrode 12 is about 1 mm to about 10 mm.
A rotating shaft 6a of a motor 6 is attached to the second discharge electrode 12 such that the center of the first discharge electrode 11 and the center of the second discharge electrode 12 are substantially on the same rotating axis of the rotating shaft 6a. The rotating shaft 6a is introduced into the chamber 10 with, for example, a mechanical seal. The mechanical seal allows the rotating shaft 6a to rotate with the depressurized atmosphere kept in the chamber 10.
A first wiper 12a and a second wiper 12b formed of, for example, carbon brush or the like are provided below the second discharge electrode 12.
The second wiper 12b is electrically connected to the second discharge electrode 12. The first wiper 12a is electrically connected to the first discharge electrode 11 through a through hole 12c penetrating the second discharge electrode 12.
Insulation breakdown does not occur between the first wiper 12a and the second discharge electrode 12. The first wiper 12a and the second wiper 12b are configured as electrical contact points keeping electrical connection while the first wiper 12a and the second wiper 12b are wiped, and are connected to a pulsed power supply 15.
The pulsed power supply 15 supplies pulsed power between the rotating first discharge electrode 11 and second discharge electrode 12 through the first wiper 12a and the second wiper 12b.
Peripheral portions of the first discharge electrode 11 and the second discharge electrode 12, which are the disk-shaped members made of metal, are tapered to produce a pointed edge. In other words, a diameter of the first discharge electrode 11 on a side facing the second discharge electrode 12 is slightly larger than a diameter of the first discharge electrode 11 on the opposite side from the second discharge electrode 12. Similarly, a diameter of the second discharge electrode 12 on a side facing the first discharge electrode 11 is slightly larger than a diameter of the second discharge electrode 12 on the opposite side from the first discharge electrode 11. When power is applied from the pulsed power supply 15 to the first discharge electrode 11 and the second discharge electrode 12 as described later, electrical discharge occurs between the tapered edge portions of the electrodes.
When the electrical discharge occurs, temperature of the vicinity of the electrodes becomes high. Accordingly, the first discharge electrode 11 and the second discharge electrode 12 are made of high melting point metal such as tungsten, molybdenum, and tantalum. The insulator is made of, for example, silicon nitride, aluminum nitride, diamond, and the like.
Solid tin (Sn) or solid lithium (Li) as a raw material for producing high temperature plasma is supplied to the discharge portion 1. The raw material is supplied from a raw material supply unit 14 to a groove portion 12d formed around the peripheral portion of the second discharge electrode 12. That is, the raw material is supplied into the groove portion 12d of the disk-shaped member that forms the second discharge electrode 12. The motor 6 rotates in only one direction, the rotating shaft 6a is rotated by the operation of the motor 6, and the first discharge electrode 11 and the second discharge electrode 12 connected to the rotating shaft 6a are rotated in one direction. Sn or Li supplied to the groove portion 12d of the second discharge electrode 12 is moved toward the EUV radiation outgoing side in the discharge portion 1 by the rotation of the second discharge electrode 12.
The chamber 10 is provided with a laser irradiator 5 for irradiating laser onto the Sn or Li that is moved toward the EUV radiation outgoing side. The laser irradiator 5 may be formed of YAG laser, CO2 laser, or the like.
The laser from the laser irradiator 5 is irradiated onto Sn or Li which is in the groove portion of the second discharge electrode 12 moved toward the EUV radiation outgoing side through a laser collecting means and a laser transmission window portion (not shown) in the chamber 10. As described above, the diameter of the second discharge electrode 12 is larger than that of the first discharge electrode 11. Accordingly, the laser passes by the side of the first discharge electrode 11 and is irradiated onto the groove portion 12d of the second discharge electrode 12.
The EUV radiation from the discharge portion 1 is radiated as follows.
The laser is irradiated from the laser irradiator 5 onto the Sn or Li in the groove portion 12d. The Sn or Li irradiated with the laser is evaporated between the first discharge electrode 11 and the second discharge electrode 12, and a part of the Sn or Li is ionized. Under such a condition, when the pulsed power supply 15 applies pulsed power, a voltage of which is about +20 kV to about −20 kV, between the first discharge electrode 11 and the second discharge electrode 12, an electrical discharge occurs between the tapered edge portions provided at the peripheral portions of the first discharge electrode 11 and the second discharge electrode 12.
At this time, pulse-shaped high current flows at the partially ionized portion of Sn or Li evaporated between the first discharge electrode 11 and the second discharge electrode 12. A high temperature plasma P is formed, at the peripheral portion of the both electrodes, from the evaporated Sn or Li by Joule heating of the pinch effect, and EUV radiation having a wavelength of 13.5 nm radiates from the high temperature plasma P. As described above, since the pulsed power is applied between the first discharge electrode 11 and the second discharge electrode 12, the electrical discharge is a pulse discharge and the radiating EUV radiation is a pulse radiation having a pulse shape.
The EUV radiation radiated from the discharge portion 1 is collected by an oblique-incidence type EUV collector mirror 2, and is guided, via the EUV radiation output portion 4 provided in the second chamber lob, to the irradiation optical system of the exposure tool (not shown) provided in a third chamber 10c.
The EUV collector mirror 2 includes a plurality of, for example, rotating oval bodies having different diameters or paraboloid mirrors. The rotating center axes of the mirrors are overlapped with one another so that focal positions thereof substantially coincide with one another. The mirrors are configured to satisfactorily reflect EUV radiation having an oblique incident angle of about 0 to about 25 degrees by minutely coating a reflection side of a base material having a smooth surface formed of, for example, nickel (Ni) or the like, with a metal film such as ruthenium (Ru), molybdenum (Mo), or rhodium (Rh).
A foil trap 3 is disposed between the discharge portion 1 and the EUV collector mirror 2 to prevent damage of the EUV collector mirror 2. The foil trap 3 catches debris such as metal powder generated by sputtering the first discharge electrode 11 and the second discharge electrode 12 which are in contact with the high temperature plasma, or debris caused by Sn or Li that is a radiating species, and thus allows only EUV radiation to pass. The foil trap 3 includes a plurality of plates (foil) and a ring-shaped supporter for supporting the plates. The plates are disposed in a diameter direction of a high temperature plasma generating area so as not to block the EUV radiation from the high temperature plasma.
When the foil trap 3 is provided between the discharge portion 1 and the EUV collector mirror 2, pressure between the high temperature plasma P and the foil trap 3 increases and thus collision of debris increases. The debris reduces the kinetic energy by repeated collision. Accordingly, energy of the debris is reduced when the debris collides with the EUV collector mirror 2, and thus it is possible to reduce damage to the EUV collector mirror 2.
As described above, the EUV radiation radiated from the high temperature plasma P generated in the EUV radiation source is collected by the EUV collector mirror 2, and is sent out via the EUV radiation output portion 4 of the second chamber 10b.
The EUV radiation output portion 4 is connected to an EUV radiation output portion 7 provided in a housing of the exposure tool. That is, the EUV radiation collected from the EUV collector mirror 2 enters the exposure tool through the EUV radiation output portion 4 and the EUV radiation output portion 7.
The exposure tool has an illumination optical system for application of the incident EUV radiation. The illumination optical system forms a shape of the EUV radiation incident from the EUV radiation output portion 7, and then irradiates a mask formed with a circuit pattern.
The optical system in the exposure tool has no glass material allowing the EUV radiation to pass therethrough. Accordingly, a reflection optical system is employed instead of a transmission optical system such as a lens system, and the illumination optical system includes reflection type optical elements such as one or more reflection mirrors. The light reflected by the reflection type mask is reduced and projected onto a work (for example, a wafer coated with resist) by a projection optical system, and a reduced circuit pattern of the mask is formed on the work. Similarly to the illumination optical system, the projection optical system also employs a reflection optical system, and includes reflection type optical elements such as one or more reflection mirrors.
The EUV radiation is absorbed by air, and thus components such as an illumination optical system of an exposure tool, a mask, a projection optical system, a work, and a work stage are installed in a vacuum. These components are installed in a housing of the exposure tool. Gas existing in the housing is exhausted by a gas exhaust unit, and an inside of the housing is kept at a low pressure.
The EUV radiation receiving unit 7 provided in the housing of the exposure tool and the EUV radiation output portion 4 provided in the EUV radiation source are connected to each other through a connection device 20. The inside of the chamber (second chamber 10b) of the EUV radiation source and the inside of the housing (third chamber 10c) of the exposure tool have a structure capable of differential pumping by the gas exhaust units, respectively.
In the EUV radiation source, various kinds of gas are used such as a gas for generating a high temperature plasma for radiating the EUV radiation, a gas for reducing the debris caused by the high temperature plasma or electrode materials, and a gas for cleaning an inner wall of the chamber or the collector mirror. For example, JP-T-2006-529057 describes that cleaning of debris may be performed with halogen gas.
Meanwhile, the inside of the exposure tool connected to the EUV radiation source is kept in a high vacuum state to prevent attenuation of the EUV radiation. For this reason, it is advantageous to prevent movement of gas from the EUV radiation source to the exposure tool. For example, JP-A-2004-172626 describes a related art technique for forming a barrier using a gas lock in a lithography device in which an EUV radiation source and an exposure tool are connected each other.
As described above, in the EUV radiation source for radiating the extreme ultraviolet radiation, the various kinds of gas are used. As such, the pressure of the EUV radiation source is set to about 1 Pa.
Meanwhile, the inside of the exposure tool, which is connected to the EUV radiation source and to which the extreme ultraviolet radiation is introduced, is also kept in a high vacuum state (for example, about 10−5 Pa) to prevent attenuation of the EUV radiation. Accordingly, unnecessary gas is removed from the inside of the exposure tool by performing a degassing process.
Thus, since the inner environments in the EUV radiation source and the exposure tool are different from each other, it is advantageous to prevent movement of gas from the EUV radiation source to the exposure tool on an interface between them. For example, a halogen gas used for cleaning is likely to decrease the characteristics of the optical components or to have an influence on a movement mechanism of the optical components. Accordingly, it is advantageous to prevent halogen gas from flowing into the exposure tool.
As a general blocking method for preventing the movement of gas, a physical blocking means (e.g., a gate valve, a thin film filter) has been proposed in the related art. However, in the related art gate valve, there is a disadvantage in that a connection portion is covered with a lid. Accordingly, the related art gate valve cannot be used during an exposure operation, i.e., during the generation of EUV radiation.
On the other hand, the related art thin film filter can be used during the exposure operation by selecting a material allowing the EUV radiation to pass therethrough. However, a pressure difference between the EUV radiation source and the exposure tool may be on the order of about 105 Pa. Accordingly, there is a disadvantage in that in a case where the thin film filter has a thickness capable of withstanding the pressure difference, permeability of the EUV radiation decreases.
Accordingly, for example, as described in FIG. 7, the connection device 20 is provided in a differential pumping portion between the EUV radiation receiving portion 7 of the exposure tool and the EUV radiation output portion 4 of the second chamber 10b. In other words, the connection device 20 forms an interface between the EUV radiation source and the exposure tool. Gas is supplied from a third gas supply unit 20a to the connection device 20, and thus the movement of the gas on the interface between the EUV radiation source and the exposure tool is controlled.
That is, as shown in FIG. 8, a gas for preventing the movement of gas between the EUV radiation source and the exposure tool (hereinafter "stop gas") is supplied from the gas supply unit 20a to the connection device 20. The stop gas is allowed to flow in both directions toward the EUV radiation source and the exposure tool, and inflow of gas such as a cleaning gas from the EUV radiation source to the exposure tool is prevented.
JP-A-2004-172626 describes a related art lithography device for coupling a first chamber and a second chamber using a gas lock. In this case, the gas of the gas lock forms a barrier separating the first chamber and the second chamber.
FIG. 9 shows an example of the gas pressure of the related art connection device 20 in case of using differential pumping and a stop gas. In FIG. 9, a horizontal axis represents a distance from a stop gas inlet in a center-axis direction (i.e., an X-axis direction in FIG. 8), and the right side in the same figure represents the EUV radiation source side. A position of 0 in the horizontal axis is a center position of the stop gas inlet (in FIG. 9, the position of 0 is shown in the scale of the horizontal axis). A vertical axis represents a pressure (Pa).
A graph A represents a pressure distribution of the stop gas supplied to a differential pumping portion, and a graph B represents a pressure distribution of a gas (e.g., cleaning gas) supplied to the EUV radiation source.
As can be seen from FIG. 9, the gas on the EUV radiation source side does not flow into the exposure tool side by the operations of the differential pumping and the stop gas.
However, while the related art connection device acts to prevent gas from flowing between the first chamber and the second chamber, the related art connection device has a few disadvantages. For example, when the stop gas is supplied to the differential pumping portion as described above, a high pressure layer is formed by the stop gas with respect to a passing direction of the EUV radiation. Accordingly, there is a disadvantage in that the EUV radiation does not easily pass through the high pressure layer (i.e., a permeability decreases). For example, as shown in FIG. 9, a thickness of a part where the pressure of the stop gas is 100 Pa with respect to the passing direction of the EUV radiation is about 9 mm. To reduce the thickness of the layer, it is conceivable to reduce a supply rate of the stop gas. However, if the supply rate of the stop gas is reduced to reduce the thickness, there is a disadvantage in that gas easily flows from the EUV radiation source into the exposure tool.
As described above, in order to prevent the movement of gas, it is conceivable to use the related art gate valve or the related art thin film filter. However, the related art gate valve has a disadvantage in that the gate valve cannot be used during the EUV radiation generation. The related art film filter has a disadvantage in that the permeability of the EUV radiation decreases.


A case for extruded powders comprising a surface having at least one groove with extruded powders disposed therein. The powders are preferably not all the same color. Preferably, forty percent or more of each extruded powder rises above the surface and preferably, the cross sectional shape of each groove matches the cross sectional shape of that part of the extruded powder that is disposed in the groove. Optional dividers separate the extruded powders so that they do not contact each other. Optional restraints inhibit the powders from coming out of the grooves. Also optional are an outer container into which the surface is disposed and cover to protect the powders when not in use. The case may comprise other cosmetic elements such as an applicator, a mirror or a pan or pressed powder.

Compacted cosmetic powders of different colors are frequently packaged in a single container. This provides the user with a customizable cosmetic, because the user may apply to her skin whatever quantity of each color she chooses, thus creating a personal effect. A package with several colors of powder allows the user to experiment until she achieves the look she wants. However, there are practical manufacturing difficulties associated with providing several colors of powder in a single package. Consequently, a container that conveniently holds more than three or four differently colored powders is, to the best of the applicant's knowledge, unknown. Consequently, color shading effects, i.e. amber effects, that may only be achieved with a significantly larger number of colors have been unavailable to the consumer. Here and throughout this specification, the term "ombre effects" refers to the infinite number of gradations of tone that can achieved by mixing in different proportions, a large number of colored powders. Several attempts, have been made to address the various issues associated with providing a large number of powders in a single package. None of these attempts, here summarized, addresses all of the issues as does the present invention.
U.S. Pat. Nos. 4,887,409 and 4,887,410: These multi-colored powder compacts have no dividers between the different colors of powder, giving sharp lines of transition in any desired pattern. The drawbacks of this method include having to fill the pan with loose powder through a specially designed partitioned sleeve, followed by a partial compressing of the powder of each individual color by a specially designed multi-piston assembly, removal of the sleeve and then a second pressing of the complete powder surface by yet another piston. The filling process requires custom equipment and has several steps in which a breakdown in the filling process may occur. The filling process also deals with loose powder. This means that special handling is required to keep the pan and finished compact clean. This is a drawback of the majority of solid powder compacts. The present invention does not require any specially designed filling equipment and filling the case does not deal with loose powder.
U.S. Pat. No. 5,086,791: In this process different loose powders or different colors are introduced in layers into a relatively deep pan. After each layer is filled, the powder is compressed with a piston and the next layer is deposited. Once all the layers have been filled and compressed, the powder is excavated to reveal portions of the multiple layers and to provide a contoured surface in a desired pattern. While the contoured surface is said to be an aesthetic advantage over the usual flat surface associated with pressed powders, this filling process involves several steps, wastes the excavated powder which is a mixture of powders that cannot be separated and requires a deeper than usual pan so that a specially designed compact would be needed. It also has the drawback of filling loose powder and is practically limited to about five different powders or colors of powder. The present invention does not require "excavation," does not waste any product in the filling process, may easily be filled with one to fifty or more colors or powders and may have a contoured surface.
U.S. Pat. No. 4,705,051: This is a powder container for holding at least two colors of loose powder, each in a separate compartment. An adjustable amount of each powder may be introduced into a mixing compartment through a valve. The mixed powder is dispensed on a brush for application. The asserted advantage here is that the user may custom mix the powder to achieve the desired color or effect. Disadvantageously, this device is complex. It requires the use of spring loaded flapper valves, the flow of loose powder and is practically limited in the number of compartments that may be added for differently colored powders. It deals entirely with loose powder which is messier than compacted or extruded powder. Flapper valves and springs become inhibited with powder, deteriorating their function, especially if the loose powder cakes through absorption of moisture. The present invention does not use valves or springs or any moving parts. It does not require the user to pre-mix messy loose powder.
Dry powder sticks by extrusion are known. See for example U.S. Pat. Nos. 3,800,034 and 3,972,666, herein incorporated by reference in their entirety. These patents describe a process for preparing dry powder makeup sticks by extrusion. Extruded power sticks offer an alternative to pressed powders, having advantages in handling and filling. One disadvantage arises because the sticks are generally used by directly drawing the stick over the skin. To this end, the sticks must be formulated to meet conflicting requirements, i.e., possess cohesive strength sufficient to prevent breakage when being drawn over the skin, while being soft enough to yield adequate "pay-off". Pay-off refers to the stick's ability to deposit product as it is drawn over a surface, i.e., the skin. These conflicting requirements place limitations on the chemical composition of the product. Because of their intended method of use, extruded stick powders are not typically applied with a brush and different colors are not typically mixed prior to application. In contrast, the powder case of the present invention, for the first time, permits the use of a brush applicator to mix and apply multiple colors of extruded stick powders. Furthermore, because the sticks are well supported by the case and do not directly contact the skin, they do not have to be formulated to resist breakage to the same degree as the sticks described above. This makes it easier to formulate the sticks to have adequate payoff. Therefore, the present powder case offers more flexibility in the chemical composition of the powder product itself.

Case for presenting and using cosmetic powders


A rotating Christmas tree stand that includes a rotating electric supply socket to provide electrical power to the lights decorating the Christmas tree; that includes a fluid reservoir for supplying fluid to the Christmas tree; that includes a mixing mechanism for mixing fertilizing agents into the fluid within the fluid reservoir; and that includes a stand assembly and a rotating tree support assembly rotatably supported on the stand assembly.

It is often desirable to display a decorated Christmas tree. Although the entire Christmas tree is typically decorated, it is often difficult to find a location within a home or other building that provides views of all sides of the Christmas tree. It would be a benefit, therefore, to have a Christmas tree stand that was rotatable to allow for display of the entire Christmas tree. Because many Christmas trees are decorated with electric lights, it would be a further benefit to have a rotating Christmas tree stand that included a rotating electric supply socket to provide electrical power to the lights decorating the Christmas tree without the worry of the electrical supply wires becoming tangled. Because live or fresh Christmas trees typically last longer when provided with fluids, it would be a further benefit to have a Christmas tree stand that included a fluid reservoir for supplying fluid to the tree. In addition, because it is also considered beneficial to add fertilizing agents to the fluid supplied to the tree, it would also be a benefit to have a mixing mechanism for mixing fertilizing agents into the fluid within the fluid reservoir.


An improved hairpin expander machine equipped with a closed-loop-controlled hydraulically positioned bolster plate and a heat exchanger-holding fixture characterized by a full-length, continuous front plate, back plate, and side rails. The hairpin expander includes a novel heat exchanger bottom end plate clamping mechanism as part of the fixture. These features enable the hairpin expander to provide larger expansion ratios and exert greater forces with tighter control, which is required for producing heat exchangers with reduced diameter hairpin tubes according to a preferred embodiment of the invention.

1. Field of the Invention
This invention relates generally to tube and fin heat exchangers, and in particular, to manufacturing processes and equipment for producing tube and fin heat exchangers, such as for HVAC systems.
2. Description of the Prior Art
As illustrated in FIG. 1, a typical tube and fin heat exchanger (10) consists of a stack of generally planar metallic fins (12) sandwiched between a top end plate (14) and a bottom end plate (16). The terms "top" and "bottom" used for designating heat exchanger end plates are derived based on the heat exchanger orientation during expansion in a vertical hairpin expander press, as described below. The "top" and "bottom" designations are not necessarily indicative of the heat exchanger orientation in any particular installation.
The fins (12) have a number of collared holes (18) formed therethrough, and the top and bottom end plates (14, 16) have corresponding holes (20) formed therethrough. When the fins (12) and end plates (14, 16) are stacked, the holes (18, 20) are in axial alignment for receiving a number of U-shaped hairpin tubes ("hairpins") (22) through the stack. Hairpins (22) are formed by bending lengths of small tubes, typically copper, aluminum, steel or titanium, 180 degrees around a small diameter mandrel. The hairpin tubes (22) are fed, or laced, through the loosely-stacked assembly of fins from the bottom end plate (16) so that the open ends (26) of the hairpin tubes (22) extend beyond the top end plate (14). The top end plate (14) is slipped over the open ends (26) of the hairpins (22), and the hairpins (22) are mechanically expanded from within to create a tight fit with the fins (12). Finally, return bend fittings (24) are soldered or brazed to the open ends (26) of the hairpin tubes (22) to create a serpentine fluid circuit through the stack of fins (12).
FIG. 2 is a flow chart diagram that describes the manufacturing process of prior art used to mass produce tube and fin heat exchangers. Referring to both FIGS. 1 and 2, as shown in step (50), fins (12) are formed by a stamping process in a fin press, such as those produced by Burr Oak Tool, Inc. of Sturgis, Mich. Fin stock is delivered to a press in a roll of sheet metal. Various metals, heat treatments, and thicknesses may be used, but aluminum is the general industry selection. Fin stock is paid out from an uncoiler, lubricated, then fed through a press, where a die draws, details, punches collared holes, and cuts fins to a desired length and width. Stamping generally occurs in several stages. At the back end of the fin press, fins index out of the die under a vacuum hood, where a pressure differential holds them in place until discontinued, at which time (sometimes mechanically assisted by wire) the fins drop from the vacuum hood on to collection rods that pass through collared holes of the fins. The collection rods are mounted on to collection tables. Once having a full stack of fins, the collection table is removed from the back-end of the fin press. Drop rods are inserted into the fin stacks to keep the stacks intact. Operators lift stacks of fins by placing their hand at the bottom of the stack and physically lift the stack up off the collection table rods. Fin stacks then are staged for the lacing process as depicted by element (56) in FIG. 2.
As shown by step (52) in FIG. 2, the heat exchanger top and bottom end plates (14, 16) are manufactured in a stamping process that is independent of the fin stamping process (50). The end plates are typically made of a fairly stiff sheet metal. The end plates (14, 16) may also each include bends that form a channel or similar profile to provide strength and rigidity. Holes (20), which align with the collared holes (18) of the fins (12), are punched through the end plates by a press and die.
The hairpin tubes (22) are manufactured in process step (54). Referring to FIGS. 2 and 3, hairpins are typically formed in a hairpin bender machine (88), using machines such as vertical bend hairpin bender, manufactured by Burr Oak Tool, Inc. of Sturgis, Mich., to form multiple hairpins at a time. Depending on the outer diameter of the stock tubing, commonly up to six lines of tubing are typically processed simultaneously in a single hairpin bender machine (88).
A typical vertical bend hairpin bender machine (88) consists of three sections—the tubing pay-out section (90), a feeder section (92), and a bender section (94). U.S. Pat. No. 6,354,126, issued to Small, et al. and entitled "Tube Straightener and Drive Therefor," describes a typical feeder section (92), and the patent is incorporated herein in its entirety by reference. U.S. Pat. No. 5,233,853, issued to Jones G. Milliman and entitled "Stretch Straightening Hairpin Bender," describes a typical bender section, and it is also incorporated herein in its entirety by reference.
The pay-out section (90) includes a coil stand (96), also known as an uncoiler, for supporting multiple tubing spools or bare-pack tubing coils. As stock tubing (100) is paid out from bare-pack coils or spools at the pay-out section (90), the stock tubing (100) will typically contain bends and may be out-of-round at times. Thus, the feeder section usually includes correction rollers for reforming the stock tubing back to nominal dimensions.
A more detailed view of the feeder section is shown in FIG. 4. Cross-axis rollers (102) correct ovality, eccentricity, and out-of-round conditions of the stock tubing (100), returning it to a circular profile. Next, a pair of pre-size rollers (104) typically surrounds and rolls the stock tubing (100) to return any portion of stock tubing that has a slightly larger than normal outer diameter to its nominal size. In other prior art hairpin bender configurations, a stationary pre-sizing die (not illustrated) is used in place of the pre-size roller pair (104). A final pair of offset straightening rollers (106) ensures the stock tubing (100) is straight and true.
After the trio of correction rollers (102, 104, 106), a pair of conveyor belts (108) clamps the stock tubing and drives the tubing through the hairpin bender machine (88). Each line of stock tubing (100) being processed by the hairpin bender (88) is fed by the feed belt assembly (108) over a boom (110), a bend arbor clamp (112) and mandrel tip rods (114) in bender section (96). Tube draw for each tubing line continues until that tubing contacts a switch tower. Once all of the tubes have contacted their respective switch tower, the bend arbor clamp (112) engages and a tube cutter head assembly (98), located at the end of the feeder section (92), cuts and reams the tubes. Mandrel tips are extended, and boom (110) actuates, bending the cut tube sections 180 degrees about a mandrel (115), thus creating the hairpin tubes (22). Once the boom (110) actuates its limit switch (not shown), indicating a complete bend, the bend arbor clamp (112) is released, and a stripper assembly (not illustrated for simplicity) pushes the hairpin tubes (22) out of the boom (110) and off of the mandrel tip rods (114), where the hairpins (22) then fall into catch arms (also not illustrated for simplicity). The hairpins (22) are removed from the catch arms and staged in large racks for the lacing process as depicted by element (56) in FIG. 2.
As shown in step (56) of FIG. 2, the lacing process is that process in which stacks of fins (12), the bottom end plate (16), and the hairpins (22) are assembled together, typically by hand. Fin stacks are laid out on a lacing table, one stack at a time. Drop rods are removed from each fin stack as multiple stacks are assembled together on the table to form a contiguous slab of fins. The heat exchanger bottom end plate (16) is added to one end of the slab, and it is temporarily held in place with rods. These rods also help maintain fin alignment until an adequate number of the hairpin tubes have been laced through the assembly to maintain alignment. Hairpins (22) are typically hand-laced through the bottom end plate (16) into the slab of fins (12) one at a time by an operator who manually finesses them in. For conventional diameter hairpins and fins of the prior art, for example ⅜ inch diameter hairpins, lacing is a simple process, taking on average no more than five seconds per hairpin.
At this stage of assembly, the heat exchanger consists of stacks of fins (12) and a bottom end plate (16) loosely held together by hairpins (22) passing transversely through the assembly. As shown in step (58) of FIG. 2, in order to form tight metal-to-metal interfaces between the tubes and the fins of the heat exchanger so that efficient conductive heat transfer paths are created between the tubes and the fins, the hairpins (22) are expanded within the fins to create an interference fit.
The laced heat exchanger assembly is placed within a hairpin expander machine (150), and the top end plate (14) is slipped over the open ends (26) of the hairpins (22). FIG. 6 shows a typical hairpin expander (150) of prior art into which a heat exchanger assembly is vertically placed with the open ends (26) of the hairpins (22) facing upwards. Referring to FIGS. 1 and 6, hairpin expander (150) has bullets (152) located at the ends of long rods (154) for passing through the open ends (26) of the hairpins (22). Multiple bullets (152) and rods (154), two for each hairpin (22), are typically provided for simultaneously expanding all of the hairpins (22). Each bullet (152) is sized to have an outer diameter larger than the inner diameter of the hairpin tubes (22). The expander has a hydraulic ram (151), that acts upon a pressure plate (153) which in turn drives rods (154). As the expander (150) presses the bullets (152) into the hairpins (22), the bullets (152) expand the hairpins (22) into a tight, interference-fit engagement with the fins (12).
Expansion of the diameter of the hairpins causes axial shrinkage of the hairpins. Typically, about a 3-5 percent reduction in hairpin length occurs during the prior art expansion process used with conventional hairpin tube diameters (e.g. ⅜ inch). In the earlier vintage hairpin expanders (150), the heat exchanger stack is supported in the expander at the bottom end plate (16) and at the bends (23) of the hairpins (22) by a bolster plate (156). The hairpin bends (23) are supported by a receiver plate or cradle plate (158) that has semicircular grooves (161) cut therein to accommodate them. The receiver or cradle plate (158) is in turn supported on the bolster plate (156). The stack of fins (12) and the top end plate (14) "float" or rest on the bottom end plate (16). As the hairpins are expanded, the hairpins (22) are under compressive forces. Therefore, expander (150) includes a fixture (160) mounted to the expander frame, into which the heat exchanger is placed. Fixture (160) includes front and back plates (162) that laterally support the stack of fins (12) to prevent them from buckling during the expansion. Side rails (164) may be included in fixture (160) for making it easier to center the heat exchanger within the expander (150).
Because the top end plate (16) becomes initially fixed in position near the tips (26) of the hairpins (22) after expansion is first commenced, there is a concomitant shrinking and tightening of the stack of fins and end plates due to the longitudinal shrinkage of the hairpins (22) during expansion. Even with attempts to predict and compensate for the shrinkage of the hairpins with this type of expander, the process still results in heat exchangers having large dimensional variances.
The more advanced expanders of prior art employ a coil shrink rate control feature that forces all of the hairpin tubes to shrink at the same rate. With this type of expander, both the top and bottom end plates (14, 16) are held fixed within the fixture (160) at the desired dimensions, thus providing a finished heat exchanger product of having higher dimensional tolerances. The hairpin bends (23) are supported in a cradle or receiver plate (158), which is in turn supported by the bolster plate (156). During initial expansion, the hairpins (22) are in compression. However, because the top end plate is held fast within the fixture (160), after the bullets have passed through the top end plate (14), securing the top end plate near the upper ends (26) of the hairpins (22), the compressive hairpin force becomes a tensile force as the hairpin bends (23) contract and pull away from the cradle or receiver plate (158). The hairpins (22) are held by the top end plate (14) in the fixture (160) during expansion, and as the hairpins (22) contract in length, the hairpin tubing below the bullets (152) slide upwards within the stack of fins (12), moving the hairpin bends (23) toward the bottom end plate (16).
It is possible that the tensile force exerted on the hairpins (22) at the top end plate (14) by the bullets (152) during expansion may exceed the strength of the interference fit that holds the hairpins (22) in the holes (20) of the top end plate (14). If this happens, damage to the heat exchanger will occur. Therefore, with the controlled-shrink-rate expander, the bolster plate (156), which carries the cradle or receiver plate (158), is designed and arranged to move upwards at the same rate as the hairpin bends (23) move upwards, thus continuing to provide support of the hairpins.
U.S. Pat. No. 4,780,955 issued to Stroup on Nov. 1, 1988 and entitled "Apparatus for Making a Tube and Fin Heat Exchanger" describes an expander that employs coil shrink rate control, and the patent is incorporated herein in its entirety by reference. The '955 patent teaches that the bolster plate may be mechanically driven as a function of the position of the ram cylinder that drives the pressure plate, the rods and the expansion bullets. For example, for every inch of downward travel of the ram cylinder, a cam arrangement (not illustrated) drives the bolster upward 0.03 inches. The '955 patent also discloses a second arrangement in which a pneumatic actuator (not illustrated) drives the bolster plate upward. The pneumatic actuator force is manually selected by the operator so as to approximately balance the force applied to the hairpins by the bullets.
In the controlled-shrink-rate expander of prior art described above, the upward movement of the bolster plate and receiver or saddle plate tends to apply an upward force on the heat exchanger bottom end plate. The bottom end plate of the heat exchanger is held fast within the expander fixture by a piano hinge clamp arrangement, as illustrated in FIGS. 7-8. FIG. 7 illustrates the bottom end of a heat exchanger (10) that is to be positioned within the expander for expanding the hairpins into an interference-fit engagement within the stack of fins (12). The hairpin bends (23) are shown extending beyond the bottom end plate (16) of the laced heat exchanger. The heat exchanger fins are not illustrated for simplicity. Fixture base plate (165) receives and positions the heat exchanger bottom end plate (16) during the shrink-rate-controlled expansion process described above. Base plate (165) may have a recessed seat (166) into which bottom end plate (16) is received. A slot (167) is formed through base plate (165) for allowing the hairpin bends (23) to pass therethrough and to be received into the receiver or cradle plate (158). Two piano hinge clamps (168) (only one is shown for simplicity) are attached to fixture base plate (165) and are arranged to be folded over the seated bottom end plate (16), retaining the bottom end plate (16) in the recessed seat (166) of the fixture plate (165). A pair of latch mechanisms (170) are secured to studs (172) in fixture plate (165). The latch mechanisms (170) are rotatable for locking the piano hinge clamps (168) into the folded clamping position or for allowing the piano hinge clamps (168) to swing freely.
FIG. 8 illustrates the piano hinge clamp arrangement of the fixture base plate (165) of FIG. 7, with the heat exchanger bottom end plate (16) seated in the recessed seat (166) of the base plate (165). The piano hinge clamps (168) are folded over the heat exchanger bottom end plate (16), holding the end plate fast to fixture base plate (165). The latches (170) are rotated to keep the piano hinge clamps (168) in the downward, folded position.
Referring back to FIGS. 1 and 2, after the expansion process, a number of short return bend tubes (24) are soldered, brazed or welded to the open ends (26) of the hairpins (22) to create one or more long serpentine circuits from the hairpins for fluid flow. Additionally, one or more cross-over tubes (not shown), which connect various hydraulic circuits, may be soldered, brazed or welded to the open ends (26) of the hairpins (22). In the typical manufacturing process used for manufacturing prior art ⅜ inch tubing heat exchangers, for example, the return bends (26) and the cross-over tubes are brazed to the heat exchanger (10) in an autobrazing process, depicted as step (60), in the flowchart of FIG. 2. The tubes are hand-assembled with brazing rings, and the heat exchanger is run through a furnace, wherein the joints are brazed.
After the autobrazing step (60) in the heat exchanger manufacturing process of prior art, a leak check (62) is performed. For each circuit, one end is plugged while a pressure-decay monitoring device is connected to the other end. If the circuits hold pressure, there are no leaks.
Finally, for heat exchangers used in HVAC systems, in step (64), subcooler, liquid and suction manifolds are manually brazed to the heat exchanger circuits.
There is concern with the effects of R22 refrigerant in depleting the ozone layer, and so the new HVAC systems are designed to use R410 refrigerant. R410 refrigerant systems operate at higher pressures than their R22 counterparts. Higher operating pressure allows the use of smaller diameter tubing in heat exchanger coils of condensers and heat pumps. Smaller diameter tubing provides a better ratio of heat transfer surface areas, has merits in terms of pressure drop on the air side because of reduced form drag, and requires less material to provide the same amount of heat transfer surface area, which is especially attractive from a commercial perspective. Consequently, strong desire exists among HVAC manufacturers to design manufacturing processes capable of realizing small diameter product. The current industry standard diameter is ⅜ inches, although some manufacturers use 7 mm. Other manufacturers use 5 mm coils to produce heat exchangers having short lengths, for example no longer than 36 inches. However, when the hairpin tubing becomes too small, both the lacing process and the expansion process become exceedingly difficult, and commercially viable manufacturing of any but the smallest heat exchangers has previously not been possible. For example, heat exchangers six or more feet in length are readily manufactured using ⅜ inch copper tubing. However, when 5 mm copper tubing is used, before the present invention, it has not been commercially feasible to manufacture a heat exchanger longer than about 36 inches—the 5 mm copper tubing is too flimsy to readily lace and expand long heat exchangers, and the concomitant manufacturing time is too long to justify the expense of producing the 5 mm heat exchanger.
It is desirable, therefore, to provide a manufacturing process and system that allows tube and fin heat exchangers characterized by small diameter hairpin tubing, such as 5 mm copper tubing, to be quickly, easily, and cost-effectively manufactured.

Hairpin expander machine for manufacturing tube and fin heat exchangers with reduced tube diameter


A cut valve with a check valve includes a body case, a cap member, positive and negative pressure valves, and first and second springs. The body case defines a vent hole. The cap member is fitted to an upper portion of the body case. The positive pressure valve is made of resin, defines an opening part, and is disposed to be contactable with and separable from the vent hole from above. The first spring is disposed on the positive pressure valve and presses the positive pressure valve in a direction in which the positive pressure valve closes the vent hole. The negative pressure valve is made of resin and is disposed to be contactable with and separable from the opening part from below. The second spring presses the negative pressure valve in a direction in which the negative pressure valve closes the opening part.

1. Field of the Invention
The present invention relates to a cut valve with a check valve attached to a fuel tank of, for example, an automobile and including a cut valve for preventing fuel, which is shaken by a turn and a tilt of the automobile, from leaking out of the tank, and a check valve for feeding fuel vapor to a canister according to the internal pressure of the tank.
2. Description of the Related Art
A cut valve for preventing fuel, which is shaken by a turn and a tilt of an automobile, from leaking out of a fuel tank of the automobile is attached thereto. Further, a communication hole opened and closed by this cut valve is connected through a check valve to a canister disposed outside the tank. Furthermore, the check valve is connected through a pipe to the canister.
Especially, in the case of a resin fuel tank, a cut valve is attached to an opening portion defined in an upper wall of the tank by, for example, welding. Further, a communication hole of this cut valve is connected to the check valve through a pipe. Furthermore, the check valve is connected to a canister through a pipe.
However, the aforementioned structure including the valves and the pipes needs to connect the cut valve and the check valve and to also connect the check valve and the canister. Thus, a piping operation is cumbersome. Moreover, because the cut valve and the check valve should be attached to different places, an operation of attaching the valves thereto is time-consuming. Additionally, because this structure needs two valves, the number of components increases, so that the management of components is troublesome, and that the cost of the components becomes high.
Meanwhile, U.S. Pat. No. 5,582,198 discloses a fuel shut-off device, which is disposed in a fuel tank, for bidirectionally passing fuel vapor between the fuel tank and an external device and for preventing fuel liquid from flowing out to the external device. A partition wall is provided in a case body defining a first connecting port that communicates with the exterior. A second connecting port is defined in this partition wall. A valve chamber is formed between the partition wall and the first connecting port. This valve chamber accommodates a first valve member pressed by a first valve member spring in a direction, in which the first valve member closes the second connecting port, and also accommodates a second valve member pressed by a second valve member spring in such a way as to close a communication hole, which is opened in the first valve member, from a partition wall side. Also, a float valve for opening and closing the second connecting port is provided in a part of the case body, which is lower than the partition wall.


An amplitude discrimination circuit separates a received video signal into a signal component with a minute amplitude level and other signal component with a high amplitude level. A contour correction circuit performs contour correction processing on a signal with the high amplitude level and a nonlinear processing circuit performs nonlinear processing after adding the signal with high amplitude level to an output from a delay circuit which delays the received video signal by the time required for the contour correction processing performed by the contour correction circuit. A minute amplitude contour correction circuit performs contour correction processing on the signal with the minute amplitude level and an adder circuit adds the signal with the minute amplitude level to an output from the nonlinear processing circuit after delaying the signal with the minute amplitude level by the time required for the nonlinear processing performed by a delay circuit.

1. Field of the Invention
The present invention relates to an apparatus and a method for processing a video signal for displaying a video signal onto such as a flat panel type display, and specifically, relates to an improvement in a horizontal contour correction for the apparatus and the method related thereto.
2. Description of the Related Art
In recent years, a flat panel type display using, for example, a liquid crystal panel or a plasma display panel has become widely used. For this kind of display, a video projection type, or so-called projector tends to become widely used.
Incidentally, in such a display apparatus performs contour correction processing to enhance its contour component for an input video signal. A technique to extract a contour component of a brightness signal and vary a contour correction amount in response to its amplitude width is disclosed in Jpn. Pat. Appln. KOKAI Publication No. 11-243496.
However, the technique for performing the contour correction processing to a video signal has not developed perfectly and has been sill in a developing stage, and it is therefore strongly desired for a method further appropriate for practical use to be developed, in respect of a variety of points.

Apparatus and method for processing video signal


The use of certain IL-6-type cytokines for the in vitro maturation of mammalian oocytes is described. The in vitro matured oocytes may be used in in vitro fertilization protocols.

1. Field of the Invention
The present invention relates to methods of in vitro maturation of mammalian oocytes.
2. Description of Related Art
a. Ovary
The mammalian ovary is responsible for the production of mature oocytes from germ cells and the production of hormones that permit the development of secondary sexual characteristics and the successful completion of pregnancy. The ovary is roughly divided into an outer cortex and an inner, vascular medulla. The stroma of the ovary spans both the cortex, which contains the ovarian follicles in various stages of development, and medulla regions.
A mature follicle is a highly complex unit having certain distinct cell types and consists of several layers of somatic cells surrounding a fluid-filled cavity "antrum" in which resides a single oocyte bathed by follicular fluid. The follicle provides the nutrients and regulatory signals required for oocyte growth and maturation.
Oocytes present in the adult ovary develop from a definite number of primordial germ cells (PGC) that migrate from extragonadal sites to the gonadal ridge to form the primitive ovary during fetal development. Once established in the developing ovary, the proliferating PGC begin to differentiate into oogonia, which are the stem cells that give rise to all the oocytes in the ovary. The population of oogonia goes through a predetermined, species-specific number of mitotic cycles until the cells enter the prophase of meiosis and become oocytes. Meiosis becomes arrested at the diplotene stage of prophase and remains at that stage until folliculogenesis begins at puberty. The meiosis-arrested primary oocytes are contained within a primordial follicle.
b. Primordial Follicles
Primordial follicles are the fundamental developmental units of the mammalian ovary. The number of primordial follicles is determined during early life and most of them remain in a resting state. The store of primordial follicles is not renewable and serves the entire reproductive life span of the adult. Before and throughout the reproductive life of the female, a number of these primordial follicles leave the resting state and start to grow (initial recruitment). The follicles develop to the antral stage where most undergo atresia; however, some of these follicles are rescued (cyclic recruitment) to reach the preovulatory stage. The end of normal reproductive life tyically occurs when the pool of resting primordial follicles is exhausted.
c. Folliculogenesis
Folliculogenesis is the process responsible for the development of ovulatory follicles and the release of one or more mature oocytes at a fixed interval throughout the reproductive life of a female. Folliculogenesis is resumed after a long quiescent phase and involves sequential subcellular and molecular transformations by various components of the follicle. During postnatal life, ovarian follicles continue to grow, mature and either ovulate or regress. Follicles are recruited continuously until the original store is exhausted.
Primordial follicles are activated to become primary follicles. Although oocytes from primordial and primary follicles are not significantly different in size, important changes take place during the primary follicle stage. The corona radiata develops gap junctions with the oocyte and the zona pellucida begins to form between the two cell types. The zona pellucida will not completely surround the oocyte until the follicle reaches the late preantral stage. Secondary follicles begin to appear when the follicular cells of the primary follicles undergo intensive mitotic division. A secondary follicle contains at least two layers of granulosa cells with the theca cells identifiable outside the basement membrane and the follicle contains a fine capillary network. Tertiary or antral follicles are characterized by the presence of a cavity known as antrum, which is filled with follicular fluid. The first antral follicles have an extensive network of gap junctions that permits the transfer of nutrients and regulatory signals between the oocyte and the granulosa cells. Antral follicles develop until they reach the preovulatory size. Inside the antral follicle, cumulus cells surround the oocyte. In vivo, expansion of the cumulus-oocyte complex (COC) is induced after the LH surge at the endpoint of ovulation in preparation for fertilization of the oocyte.
d. Oocyte Maturation
Oocyte maturation is a complex phenomenon during which the oocyte progresses from the diplotene to the metaphase II stage (nuclear maturation) in response to the ovulatory LH surge. Once reaching the metaphase II stage, the oocyte remains arrested until fertilization takes place and the oocyte completes meiosis and forms the pronucleus. Oocyte maturation also involves transformations at the cytoplasmic level that prepare the cell to support fertilization and early embryonic development (cytoplasmic maturation). The final steps of oocyte maturation are crucial to the acquisition of functional properties necessary for further development.
e. In Vitro Fertilization
In vitro fertilization (IVF) of human oocytes is a widely practiced medical technique used to overcome various forms of female and male infertility thereby opening a vast new frontier of research and treatment for the infertile couples. Despite the success of IVF, there is a significant need for improved methods of infertility treatment because about one out of five couples are unable to achieve a successful pregnancy using current IVF treatments.
When IVF was first performed, one mature unfertilized oocyte was removed from the ovary just prior to ovulation. The mature oocyte was fertilized in a laboratory dish (in vitro) and the resulting embryo was transferred back to the woman's uterus. However, it was found that if more oocytes were available for fertilization, there were more embryos available for transfer to the uterus and this significantly increased the pregnancy rate. Therefore, the current clinical practice involves giving patients hormone injections in order to induce the maturation of approximately twenty oocytes.
The standard IVF treatment includes a long phase of hormone stimulation of the female patient, e.g. 30 days, which is initiated by administering a gonadotropin releasing hormone (GnRH) agonist or antagonist to suppress the patient's own follicle stimulating hormone (FSH) and luteinizing hormone (LH). This is followed by injections of exogenous gonadotropins, e.g. FSH and/or LH, in order to ensure development of multiple preovulatory follicles. Just prior to ovulation, multiple in vivo-matured oocytes are removed from the ovaries. The isolated mature oocytes are subsequently fertilized in vitro and cultured, typically for three to six days, before transferring the developed embryos back into the uterus at the 4-8 cell stage.
Continuous efforts have been made to optimize and simplify IVF procedures in order to improve the current overall pregnancy rate of about 25% to 35%. Due to the low pregnancy rates, it is common to transfer two to five embryos in an attempt to increase pregnancy rates.
The administration of hormone injections to induce the maturation of many oocytes simultaneously is known as controlled ovarian hyperstimulation (COH). The advantage of COH is the availability of many more mature oocytes for fertilization, which increases the chances of pregnancy. However, the woman undergoing COH must be closely monitored by daily ultrasound examinations of the ovaries and blood hormone measurements because excessive ovarian stimulation may cause ovarian hyperstimulation syndrome (OHSS), which is a serious and potentially fatal condition. COH is not effective for a number of females, including some with polycistic ovary disease.
f. In Vitro Maturation of Oocytes
The side effects associated with COH could be avoided if immature oocytes could be removed from the oocytes and matured in vitro. Mammalian oocytes undergo spontaneous maturation upon removal from the follicle. Although oocytes matured in vitro have rates of nuclear maturation, fertilization and cleavage similar to in vivo matured oocytes, in vitro matured oocytes have significantly lower blastocyst rates and developmental potential.
Early in each menstrual cycle, several oocytes begin to grow in preparation for undergoing maturation and becoming developmentally competent, i.e., competent to be fertilized and develop into a healthy fetus. By approximately the fifth to seventh day of the cycle, one oocyte becomes dominant and continues to grow while the other oocytes are induced to degenerate. Once an oocyte becomes dominant, it grows and undergoes metabolic changes for approximately one week prior to becoming mature at the time of ovulation. Oocytes that do not undergo this growth phase will mature in vitro and can be fertilized, but are less likely to be developmentally competent. Therefore, the optimal time to obtain the largest number of immature oocytes is early in the cycle before any oocytes have begun to degenerate. However, oocytes removed early in the menstrual cycle and matured in vitro, are less likely to be developmentally competent.
Numerous events within the antral follicle affect oocyte maturation and the acquisition of developmental competency, including: (i) interactions between somatic cells of the follicle (in particular cumulus cells) and the oocyte; (ii) the composition of follicular fluid; and (iii) the temperature and vascularity of the follicular environment. Many of these factors change with follicle size and oocyte growth. In contrast, culture conditions for IVM are based on somatic cells that often do not reflect the follicular environment, and/or have complex compositions or additives such as macromolecule supplements that are undefined in nature. Metabolites typically included in IVM media such as glucose, pyruvate, oxygen and amino acids have been shown to have differential influences on oocyte maturation and competency. Manipulation of these factors and application of gained knowledge of the in vivo environment may result in improved in vitro oocyte maturation and overall in vitro embryo production.
g. IL-6-Type Cytokines
The IL (interleukin)-6-type cytokines, which include IL-6, IL-11, LIF (leukemia inhibitory factor), OSM (oncostatin M), CNTF (ciliary neurotrophic factor), CT-1 (cardiotrophin-1) and CLC (cardiotrophin-like cytokine), activate target genes involved in differentiation, survival, apoptosis and proliferation. IL-6-type cytokines bind to plasma membrane receptor complexes containing the common signal transducing receptor chain gp 130 (glycoprotein 130). Signal transduction involves the activation of JAK (Janus kinase) tyrosine kinase family members, leading to the activation of transcription factors of the STAT (signal transducers and activators of transcription) family. Another major signaling pathway for IL-6-type cytokines is the MAPK (mitogen-activated protein kinase) cascade.
Receptors involved in recognition of the IL-6-type cytokines can be subdivided into the non-signalling α-receptors and the signal transducing receptors. The non-signalling α-receptors include, but are not limited to, IL-6Rα, IL-11Rα, and CNTFRα, where R refers to receptor. The signal transducing receptors include, but are not limited to, gp130, LIFR, and OSMR. The signal transducing receptors associate with JAKs and become tyrosine phosphorylated in response to cytokine stimulation. Each of the IL-6-type cytokines is characterized by a certain profile of receptor recruitment that in all cases involves at least one molecule of gp130.
IL-6, IL-11 and CNTF first bind specifically to their respective α-receptor subunits. Here, only the complex of cytokine and α-receptor efficiently recruits the signalling receptor subunits. IL-6 and IL-11 signal via gp130 homodimers. Most other IL-6 type cytokines signal via heterodimers of either gp130 and the LIFR (LIF, CNTF, CT-1 and CLC) or gp130 and the OSMR (OSM). OSM is able to recruit two different receptor complexes: both LIFR-gp130 and OSMR-gp130 heterodimers. LIF and OSM directly engage their signalling receptor subunits without requirement for additional α-receptor subunits.
1) LIF
LIF elicits a diversity of biological effects on many cell types, including embryonic stem cells, primordial germ cells, neurons, adipocytes, hepatocytes, and osteoblasts. LIF affects various endocrine cell types (utero-placenta unit, bone metabolism, adrenal, ovarian, and testicular). The diversity in biological activity is reflected in the various synonyms of LIF, which include hepatocyte stimulating factor III (HSF III; Baumann and Wong, J. Immunol. 143: 1163, 1989); cholinergic nerve differentiation factor (CNDF; Yamamori et al., Science 246: 1412, 1990); melanoma-derived lipoprotein lipase inhibitor (MLPLI; Mori et al., Biochem. Biophys Res. Comm. 160: 1085, 1989); human interleukin for DA cells (HILDA; Moreau et al., Nature 336: 690, 1988); differentiation factor (D-factor; Tomida et al., J. Biol. Chem. 259: 10978, 1984); differentiation inhibitory factor (DIF; Abe et al., J. Biol. Chem. 264: 8941, 1989); differentiation inhibitory activity (DIA; Smith and Hooper, Devel. Biol. 121: 1, 1987); and differentiation retarding factor (DRF; Koopman and Cotton, Exp. Cell. Res. 154: 233, 1984).
LIF plays a central role in the regulation of diverse adult and embryonic systems. In the reproductive systems, LIF is an important cytokine in early pregnancy. Indeed, female LIF knockout mice are infertile because of a defect in the process of embryonic implantation. LIF is present in human follicular fluid and its levels are regulated according to the stage of antral follicle development. LIF levels in follicular fluid are also responsive to human chorionic gonadotropin (hCG). Cultured granulosa cells from mature follicles, but not from immature follicles, exhibit an increase in LIF production after treatment with βhCG (β-human CG), suggesting that LIF might be involved in ovulation and final oocyte development. Furthermore, LIF has been shown to promote the primordial to primary follicle transition in rats.
LIF is also an important factor in the in vitro culturing of embryonic stem (ES) cells and embryonic germ (EG) cells. EG cells or ES cells retain the stem cell phenotype in vitro when cultured on a feeder layer of fibroblasts when cultured in medium conditioned by certain cells or by the exogenous addition of LIF. In the absence of feeder cells, conditioned medium or exogenous LIF, ES or EG cells spontaneously differentiate into a wide variety of cell types.
2) CT-1
CT-1 causes hypertrophy of cardiac myocytes and has pleiotropic effects on various other cell types. Pennica et al. (J Biol. Chem. 1995 May 5; 270(18): 10915-22) disclose that CT-1 inhibited the differentiation of mouse embryonic stem cells. In vitro biological assays indicated that CT-1 was active in assays where LIF was active and vice-versa. These data showed that CT-1 had a wide range of hematopoietic, neuronal, and developmental activities and that it could act via the LIF receptor and the gp130 signalling subunit. Pennica et al. predict that CT-1 should mimic the many in vitro and in vivo effects of LIF.
WO9730146 discloses a method of enhancing the maintenance of pregnancy in a mammal by culturing an embryo in a medium containing CT-1 prior to introduction of the embryo into a mammal. WO9730146 suggests that media containing CT-1 may be suitable for early manipulative procedures on the oocyte/embryo such as in vitro fertilization, embryo splitting and nuclear transfer where survival rates of embryos are low.
3) OSM
Oncostatin M (OSM) is a pleiotropic cytokine produced late in the activation cycle of T-cells and macrophages that has been extensively characterized with numerous activities attributed to it. OSM was originally isolated from conditioned media of a phorbol ester-treated histiocytic lymphoma cell line, U937, based on the ability to inhibit the growth or development of a human melanoma cell line.
OSM binds to three cell surface receptors. OSM binds to a gp130 polypeptide, also known as the IL-6 signal transduction subunit, with a low affinity. In a second, intermediate affinity interaction, OSM and LIF compete for binding to a receptor composed of the low-affinity LIF receptor and gp130. This intermediate affinity receptor complex is capable of signalling and exerting biological effects in vitro. Although this receptor complex is shared by the two cytokines, the affinity of interaction and biological signals delivered by each of the cytokines are distinct. The third receptor recognized by OSM is a high affinity receptor that is not known to bind to other cytokines. The high affinity OSM receptor is composed of gp130 and an affinity-converting subunit that is required for high affinity and functional ligand-receptor binding.
4) IL-6
Interleukin-6 (IL-6) is a multifunctional cytokine that is produced by a variety of cells such as B-cells, T-cells, monocytes, fibroblasts and endothelial cells. IL-6 exhibits several activities relating to the proliferation and/or differentiation of hematopoietic progenitor cells. These activities result from IL-6 acting alone or in combination with other cytokines such as IL-3 and IL-4. Some specific biological effects of IL-6 include terminal differentiation of B-cells, proliferation and differentiation of T-cells, regulation of the acute phase response, growth regulation of epithelial cells, the differentiation of megakaryocytes, and thrombopoiesis. In accordance with these activities and effects, the target cells for IL-6 include B-cells, T-cells, myeloma cells, megakaryocytes, monocytes, early stem cells and hepatocytes.
Though IL-6 is a multifunctional cytokine, the various biological effects it exerts are believed to be initiated by the stepwise interaction of IL-6 with two distinct receptor subunits on a cell. IL-6 first forms a complex with an 80 kD receptor subunit. This complex binds to a non-ligand subunit, which is a membrane glycoprotein designated gp130. The binding of the IL-6-80 kD receptor complex to gp130 results in signal transduction.
5) sIL-6Rα
The receptor system for IL-6 comprises two functionally different chains: a ligand-binding chain (IL-6R) and a non-ligand-binding but signal-transducing chain (gp130). The gp130 chain associates with the IL-6R/IL-6 complex, resulting in the formation of high-affinity IL-6 binding sites and signal transduction. An extracellular, soluble form of the interleukin-6 receptor (sIL-6R) has been shown to mediate the IL-6 signal through membrane-anchored gp130.
6) IL-6/sIL-6Rα Chimera
A complex of sIL-6R and IL-6 (IL-6/sIL-6Rα chimera) can associate with gp130 expressed on both IL-6R-negative and IL-6R-positive cells. This association induces the homodimerization of gp 130 and the activation of the JAK-STAT pathway thereby leading to cellular response.

Use of IL-6-type cytokines for maturation of oocytes


According to one embodiment, a housing of an electronic apparatus includes a first sidewall portion provided with an air vent, a ceiling wall portion extending from an upper end of the first sidewall portion toward the outside of the housing, and a pair of second sidewall portions which extend from respective side end portions of the first sidewall portion toward the outside of the housing and are opposed to each other.

1. Field
One embodiment of the present invention relates to an electronic apparatus including a housing with an air vent, for example, including a liquid-proof structure around the air vent.
2. Description of the Related Art
Electronic apparatuses such as portable computers have a cooling fan, used for cooling mounted parts, inside the housing thereof. The housing of such electronic apparatuses has air vents for taking in or out the air between the inside and the outside of the housing. If water or other liquid is accidentally spilled on such electronic apparatuses, the liquid may infiltrate into the housing through the air vents.
Jpn. Pat. Appln. KOKAI Pub. No. 8-322114 discloses an outdoor power switchboard which is aimed at preventing infiltration of rainwater into the main body. The outdoor power switchboard has a rain-checking board between a heat-radiating air inlet and a ventilating air inlet. A drain outlet is formed below the rain-checking board. Rainwater entered through the ventilating air inlet is blocked by the rain-checking board, and flows into the drain outlet.
Although the above rain-proof structure is preferable as a drip-proof structure for power switchboards, it cannot be applied to electronic apparatuses such as portable computers without any change. For example, if a rain-checking board is provided inside the housing of electronic apparatuses, a large dead space is formed in the housing. This interferes with reduction in size of electronic apparatuses, which is required recent years.


A mono-lens eyeglasses includes a frame, a mono-lens and two temples. The frame has a center opening respectively in two ends, and a long groove in a lower edge for an upper edge of the mono-lens to fit in. The mono-lens has a notch formed respectively in two ends for a front end of each temple to engage in or disengage from by swinging the temple. Then the mono-lens may by removed from the frame and replaced with a new one by swinging the temple with the front end disengaged from the notch of the mono-lens without need of any tools.

This invention relates to mono-lens eyeglasses, particularly to one having its mono-lens alterable easily for various needs of users with no tools used.
First known conventional mono-lens eyeglasses shown in FIG. 4 includes a frame 90, a mono-lens 95, two temples 97 combined together. The frame 90 is provided with a long groove 91 formed in a lower edge for an upper edge of the mono-lens 95 to fit therein, and a recess 92 respectively formed in a rear side of two ends and a hole 93 bored in each recess 92. The mono-lens 95 gas a hole 96 corresponding to the hole 93 of the frame 90. Each temple 97 has a front end provided with a hole 98 corresponding to the hole 93 of the frame 3, and its front end fits in each recess 92 and is secured with the frame 90 with screw 94.
The first conventional mono-lens eyeglasses are especially used in sports activities, and various kinds of lenses are needed for various kinds of sports. So users change lenses by replacing processes, wherein tools such as drivers are required for removing screws. But where are drivers ? They cannot be carried with by sportsmen engaging in sports.
Next, second known conventional mono-lens eyeglasses shown in FIG. 5 has a more simple structure, including a frame 90 provided with a long groove 91 in a lower edge for an upper edge of a mono-lens 95 to fit therein, and two temples 97 combined with two ends of the frame 90. In use of the second conventional mono-lens eyeglasses if the mono-lens are frequently changed, tightness of the mono-lens against the groove may gradually deteriorated to result in the mono-lens falling off the groove easily in sport activities.


The invention relates to stents, in particular to a stent for insertion in a vein of a human or animal body. The invention also relates to a catheter stent insertion device for inserting a stent according to the invention in a vein of a human or animal body. The invention also relates to a method for inserting a stent according to the invention in a vein of a human or animal body using a catheter stent insertion device according to the invention.

Stents are widely used in medicine to keep the passageway open of the lumen of an anatomic vessel or duct. There is a wide variety of stents used for different purposes, from expandable coronary, vascular and biliary stents, to simple plastic stents used to allow the flow of urine between kidney and bladder.
In particular, vascular stents are commonly placed in arteries and veins in order to support the affected, weakened vessel wall of the artery or vein, as part of angioplasty. The commonly used procedure of treatment implements a catheter to insert and guide an expandable stent towards the site of the weakened vessel wall. The catheter containing the compressed peripheral stent is hereto inserted into the femoral artery or vein and guided using suitable imaging techniques, such as fluoroscopy, towards the site of deployment. Once the catheter is properly positioned the compressed stent is deployed and expanded against the inner vessel wall of the artery or vein.
Because of the external compression and mechanical forces subjected to these locations, flexible stent materials such as nitinol are used in a majority of peripheral stent placements.
Segmental stents being composed of at least two individual interconnected stent segments with a high radial force and high flexibility can be implemented within veins, due to the low shear stress conditions in the venous system. A problem associated with such stents being assembled of multiple stent segments is that once the most proximal stent segment is being deployed from the catheter stent insertion device at the desired or intended deployment location within the vein, the deployed stent segment immediately will expand into its expanded configuration and come in abutment with the inner vessel wall of the vein.
Any retraction of the deployed and expanded stent segment back into the catheter stent insertion device for repositioning purposes within the vein, for example due to a deployment (and expansion) on an incorrect or non-preferred position within the vein, is no longer possible. The position of an already deployed and expanded first stent segment within the vein cannot be corrected and the remainder of the stent assembly yet accommodated in the catheter stent insertion device has to be deployed entirely within the vein. This may lead to a stent being deployed and expanded, which does not fully support the affected vessel wall of the vein over its intended length and as such the stenting procedure may not be considered successful.


According to the present invention, provided are a curable composition containing a (A) compound which has a structure having two or more cyclic ether groups, in the molecule and a linking group linking the cyclic ether groups, which contains an alkylene group having 4 or more carbon atoms, or a curable composition containing a compound which has, in the molecule, two or more moiety structures containing 4-membered or more cyclic ether and a moiety structure represented by the following formula (Y-I), and an ink composition comprising the curable composition and a compound represented by the following formula (i).

1. Field of the Invention
The present invention relates to a curable composition that is suitably used for an ink composition, a coating material, and an adhesive, to an ink composition that includes such a curable composition and is suitably used for inkjet recording, to an inkjet recording method, to a printed material using the same, to a planographic printing plate that is obtained using such an ink composition, to a method of manufacturing a planographic printing plate, and to an oxetane compound.
2. Description of the Related Art
Cyclic ether compounds, such as three- or four-membered rings, are known as materials having high reactivity, and are used as polymerizable compounds that are included in curable compositions applied to thermopolymerization using photocationic polymerization or acid anhydrides (for example, Japanese Patent Application Laid-Open (JP-A) No. 11-43540 and No. 11-60702).
As an image recording method of forming an image on a recording medium, such as a paper or the like, on the basis of image data signals, there are an electrophotographic method, a sublimate-type and melt-type thermal transfer method, and an inkjet method. Among these, the inkjet method is feasible with a low cost device, in which an image is directly formed on a recording medium by discharging ink on a necessary image area only. Therefore, the ink can be efficiently used and the running cost is low. In addition, the inkjet method is superior as an image recording method since noise is low.
According to the inkjet method, it is possible to print not only on a normal paper but also on a non-absorptive recording medium, such as a plastic sheet and a metal plate. However, in this case, speeding-up upon printing and high definition are key matters. Further, there is a property in which the time required for drying and curing droplets after printing have a large effect on productivity of printed materials or sharpness of printed images.
As one of the inkjet methods, there is a recording method that uses inkjet recording ink curable by irradiation of radiation. According to this method, since ink droplets are cured by irradiating radiation immediately after or after a predetermined time after ink is ejected, the productivity of printing can be increased and sharp images can be formed.
When high sensitivity of inkjet recording ink curable by irradiation of radiation, such as ultraviolet rays, is realized, high curability with respect to radiation is given, which causes numerous benefits, such as the improvement of the productivity of inkjet recording, the reduction in power consumption, the extension of lifetime due to a reduction in load on a radiation generator, and the prevention of the occurrence of volatilization of low molecule substances by insufficient curing. Further, high sensitivity means the improvement of the strength of an image formed by, in particular, inkjet recording ink. Particularly, if it is applied to the formation of a planographic printing plate, strength of the cured image area is increased, and thus high printing durability can be obtained.
Recently, such an inkjet method curable by radiation, for example, ultraviolet rays has been drawing attention from the point of relatively less odor, quick drying properties, and a capability of recording onto a non-ink absorptive recording medium. Ultraviolet ray curable ink compositions for inkjet using radical polymerization are disclosed (for example, see JP-A No. 63-235382, JP-A No. 3-216379, JP-A No. 5-214280, JP-B No. 6-21256, and JP-B No. 6-62905). Further, with an object of providing inkjet recording ink capable of recording an image without bleeding, but with high sensitivity, and high adhesiveness onto a recording medium, even for a substrate that is normally difficult to directly record by an inkjet recording method, and highly safe due to less irritation and sensitization to skin, compositions including colorants and polymerizable compounds including a specific radial polymerizable acrylate compound group are proposed (for example, see JP-A No. 2003-192943 and JP-A No. 2003-192944). Radical polymerizable ink is superior in a curing rate, and is capable of forming an image without bleeding, but have a problem in that the adhesiveness onto a recording medium is decreased due to volume shrinkage upon curing.
For this reason, with an object of improving the adhesiveness onto a recording medium, cationic polymerizable ink compositions with a lower shrinkage rate upon curing by ultraviolet rays are proposed (for example, see JP-A No. 9-183928). However, cationic polymerizable ink has a big disadvantage for practical use in that the stability during the storage is not sufficient due to a reaction based on acid generated over time. Therefore, as an attempt to improve the storage stability, techniques of adding a basic compound or a thermal base generator are proposed (for example, see JP-A No. 2003-312121, JP-A No. 2003-341217, and JP-A No. 2004-91558). However, it was found a new problem occurs in that the basic compound inhibits the function of acid generated by exposure, thus decreasing the ink curing sensitivity.
Further, multifunctional cyclic ether that is used for improving sensitivity of cationic polymerizable ink has a three-dimensional structure in which polymers obtained by curing are highly cross-linked. For this reason, flexibility of a film after curing is lowered, a crack or separation is likely to occur on the recording medium, and durability of a formed image is problematic.
As such, a curable composition that can be applied to a UV curable ink composition or the like and high sensitive to irradiation of radiation, and can be cured with sufficient flexibility, or a curable composition that has a film formation property with high sensitivity and high strength to irradiation of radiation has not been proposed yet.
An oxetane compound is a substance applied in photo-cationic polymerization or thermal polymerization using acid anhydride and heretofore, various types thereof have been reported (for example, see Japanese Patent Application Laid-open (JP-A) Nos. 2002-317139, 2005-2191 and 2000-63371).
For example, JP-A No. 2000-63371 discloses an oxetane compound represented by the following formula (oxetane ring-containing (meth)acrylate).
Oxetane ring-containing (meth)acrylate

Curable composition, ink composition, inkjet recording method, printed matter, method for producing planographic printing plate, planographic printing plate and oxetane compound


An arrangement having an annular seal extending about a machine axis, and a vessel for sealing an L-shaped gap extending along a circumferential direction between a main vessel body and a cover is provided. A radial section of the gap extends in the radial direction and circumferential direction, and an axial segment extends in the axial direction and the circumferential direction. A sealing chamber is provided in the region where the radial segment and the axial segment intersect, the chamber expanded radially and axially relative to the adjacent gap segments. A seal is disposed in the sealing chamber, and a greater pressure is present in the radial segment than in the axial segment, the pressure differential sealed by means of the seal. The seal includes a support ring disposed radially inward made of a first material, and a jacket element made of a second material.

In pressure vessels, in particular compressor housings, temperature differences between various modules of the pressure vessel frequently occur, in particular in non-steady-state operation. For example, in the case of a high pressure turbocompressor, a substantially cylindrical main housing can be closed on the end side by means of a cover which is preferably arranged at least partially in an axial overlap in the pressure container. As a consequence of temperature differences, a radial thermal relative expansion occurs between the end-side cover and the at least partially encapsulating housing main body, for which corresponding movement plays have to be provided. In addition, temperature differences between the described housing components have to be maintained deliberately even in steady-state operation, in order that boundary conditions for other components are met. For example, gas seals have to be operated in a comparatively narrow temperature range, with the result that, in refrigeration engineering, temperatures of below −100° C. make it necessary to heat the gas seal, in order for it to be possible to operate the gas seal in the allowable range. At least in the region of the axial overlap between the cover and the housing jacket with regard to the machine axis which extends in the longitudinal direction along a rotor, radial plays which are dependent on the external diameter of the cover of, for example, 2 mm/1000 mm external diameter of the cover have to be provided. The very recent trend toward ever larger compressor designs leads to plays which can no longer be sealed by means of conventional static seals, because the latter are destroyed in the gaps at the prevailing pressures and the size of the gaps to be sealed.

Arrangement having a seal, seal, and turbocompressor


An artificial neuron device according to an embodiment of the present disclosure includes a first resistor connected between an input terminal and a first node; a capacitor connected between the first node and a ground terminal; a threshold switch connected between the first node and a second node; and a second resistor connected between the second node and the ground terminal, wherein, when an input voltage of a certain level is applied to the input terminal by time, a membrane potential occurs at the first node and a spike current flows through the second node. According to present disclosure, the artificial neuron device expresses the Integrate-and-Fire function, the rate coding ability, the SFA characteristics, and the chaotic activity of the biological neuron, and therefore may be widely used for the artificial neuron network device, the large-scale brain-inspired computing system, and the artificial intelligence (AI) system.

A neuron is a nerve cell that has undergone special differentiation for information processing in vivo. The neuron includes three parts: a soma, an axon, and a dendrite. The axon is a nerve fiber that transmits a signal from the soma to another neuron. The dendrite is a fiber that accepts a signal from another neuron. That is, an end of the axon of another neuron is connected to the dendrite. The connection part is called a synapse.
One neuron receives signals from thousands (on average) to tens of thousands of axons. Therefore, in order to combine one neuron with a plurality of axons, it is necessary to make the dendrite of the neuron complicated and to widen a place where the dendrite is combined with the axons. The soma performs calculations on many input signals, and calculated answers are transmitted to another neuron through the axon. What kind of calculation (or information processing) is to be performed in such a neuron circuit network is dispersed and stored in the connection part of the dendrite, that is, the synapse.
Generally, a potential inside the neuron is lower than the outside. However, when an input signal arrives from the outside, an internal membrane potential gradually increases. When the elevated membrane potential reaches a certain potential, that is, a limit or threshold, the neuron generates a pulse-type current and the membrane potential again lowers. This means that the neuron is fired, which is transmitted as an electrical signal to another neuron.
An artificial neural circuit is a circuit that performs an operation similar to a biological nerve system. The artificial neural circuit may be used in various fields such as character recognition, image recognition, speech recognition, and face recognition. The artificial neural circuit may be implemented in a circuit using a technique such as Very Large Scale Integrated Circuits (VLSI), to a certain degree. However, it is not easy to implement complex characteristics and behavior of the biological nerve system in a circuit by the conventional method. In addition, in order to implement the artificial neural circuit using the conventional method, an area of the artificial neural circuit is widened and electric power is consumed despite being implemented in the circuit.
The present disclosure has been made to solve the above-mentioned technical problems, and it is an object of the present disclosure to provide an artificial neuron device, which satisfies characteristics and behavior of a biological neuron and has a very simple structure, thereby high density and low power consumption. It is also an object of the present disclosure to provide an artificial neuron chip including such an artificial neuron device. It is also an object of the present disclosure to provide a user apparatus including such an artificial neuron chip.

Artificial neuron device using ovonic threshold switch, artificial neuron chip and user apparatus including the same

KOREA INSTITUTE OF SCIENCE AND TECHNOLOGY