A material having a multi-denier base material layer including a plurality of fine denier fibers, the fine denier fibers of less than about 10 dpf, and a plurality of large denier filaments intermixed with the fine denier fibers which form channels in a longitudinal direction of the material, the large denier filaments of greater than about 10 dpf. A method of producing a multi-denier cover material is also disclosed.

This invention is directed to a fabric or material suitable for use as a cover material or bodyside liner for a personal care absorbent article having improved fluid handling properties.
Almost all personal care absorbent articles include a cover material or a bodyside liner, an absorbent structure or core underlying the cover material, and some type of backing material which is generally liquid impervious to help prevent leakage. The types of cover materials generally fall into two main groups based, at least in part, upon performance and aesthetic preferences. For example, in the area of feminine care and sanitary napkins, the market is polarized into two segments, women who prefer clean and dry film covers and women who prefer soft, cloth-like nonwoven covers. The advantage of film covers for sanitary napkins is that they provide a relatively clean and dry surface as menses tends to pass through the film layer and into the interior of the absorbent product. A drawback, however, is that such film layers do not provide the degree of softness and comfort that a nonwoven cover material can provide. An additional drawback is the smooth, slick, non-clothlike feel that is characteristic of many films. Nonwoven-based cover materials, on the other hand, are very soft and cloth-like in feel, but tend to retain more of the menses at or just below the surface of the cover material which, in turn, makes the product suffer from the standpoint of properties such as cleanliness and dryness. The difference in functionality is a direct result of the structure of nonwovens including small average pore size and nonuniform pore size distribution.
Conventional hydrophilic cover materials or bodyside liners in contact with the skin effectively transport body fluids into the absorbent core, but they cause a wet feel against the skin of the user and may adversely affect skin health. In addition, they may wick liquid in the plane of the layer, allowing liquid to approach the edges of the absorbent article and possibly leak or seep out.
To achieve the goal of softness and a dry feel in topsheets of absorbent articles, many manufacturers have turned to nonwoven fabrics made of hydrophobic fibers for the body-contacting topsheet. While the use of hydrophobic nonwoven fabrics results in improved dry feel, the hydrophobic material hinders wicking into the absorbent core causing fluid to pool on the surface until enough pressure is applied to permeate the structure under conditions of low pressure and flow. As a result, the fluid may run off the pad and leak.
To improve the poor wicking and absorbent properties of hydrophobic materials, it is known to apply a finish comprising surfactants on the surface of the hydrophobic fibers, rendering them wettable or introducing fibers which are intrinsically wettable. Intrinsically wettable fibers may be natural, such as cellulose, or synthetic, such as rayon, polyester, or polyamides. Although providing good intake properties, wettable fibers introduce higher fluid retention and more fluid staining.
In the case of absorbent pads for feminine care, two distinct approaches involving topsheets or covers are commonly employed. One approach is to use a soft, clothlike nonwoven hydrophilic material which increases comfort but has the drawback of fluid retention and staining. A second approach is to use an apertured plastic film of hydrophobic polymer or other materials. The hydrophobic cover material repels many body fluids while the apertures allow wicking away from the cover into the absorbent material below.
Accordingly, there is a need for an improved cover material which can provide the clean and dry feel characteristic of hydrophobic film cover materials while also delivering the softness of nonwoven cover materials.
The present invention is directed to a fabric or material suitable for use as a cover material or bodyside liner for a personal care absorbent article. The material exhibits a unique topography and texture that enhances the material""s visual and tactile properties and also increases its permeability. When used as a cover material or bodyside liner in a personal care absorbent article, the material has superior fluid handling characteristics. Further, the dryness of the cover material is improved due to the reduced surface area of the cover material which contacts the wearer""s skin.
The cover material includes a fine denier component having fibers from about 3 dpf to about 5 dpf and a large denier component having fibers or filaments from about 10 dpf to about 100 dpf. The cover material can include multiple discrete or distinct layers or the large denier filaments can be intermixed with the fine denier fibers to produce a single layer multi-denier cover material. The fine denier fibers and the large denier filaments can include the same base material, for example a polypropylene polymer material, or each can include a different base material, such as a polymer blend, to improve the softness and offset the stiffness of the large denier component.
In one embodiment of this invention, the single layer multi-denier cover material can be produced using a spunbond process, wherein the large denier filaments are spun and intermixed with the fine denier fibers. The fine denier fibers and the large denier filaments can be spun from the same spinning plates having an appropriate hole arrangement or the fibers and filaments can be spun from separate spinning plates. The filaments can be bonded to the fibers using suitable bonding methods, such as thermal bonding, through-air bonding, ultrasonic bonding and other suitable bonding methods known to those having ordinary skill in the art.
Alternatively, the cover material having distinct layers of fine denier fibers and the large denier filaments can be produced. A base material layer, for example a 0.5 osy spunbond nonwoven web having fine denier fibers of about 3 dpf to about 5 dpf fibers is formed. Subsequently, a plurality of streams each including a plurality or group of large denier filaments of about 10 dpf to about 100 dpf can be disposed or placed onto a surface of the base material layer. Desirably, but not necessarily, the streams of the large denier filaments are laid in a generally machine or longitudinal direction to produce a plurality of channels. The channels direct fluid to flow in a longitudinal direction rather than a lateral or cross-machine direction to reduce fluid leakage.
The separation or spacing between the streams of the high denier filaments can be controlled to tailor a cover material for specific needs. For example, in an absorbent system having relatively quick absorption, it may be desirable to have a small level of separation between the streams of the large denier filaments. Conversely, in an absorbent system having relatively slow absorption, it may be desirable to have a greater level of separation between the streams of the large denier filaments to increase the void volume in the cover material so a relatively large amount of fluid can be retained until the fluid is absorbed by the underlying absorbent structure without leakage.
With the foregoing in mind, it is a feature and advantage of the invention to provide a material suitable for use as a cover material or bodyside liner for a personal care absorbent article having improved fluid handling characteristics.
It is further a feature and advantage of the invention to provide a cover material or bodyside liner for a personal care absorbent article having a unique topography and texture as well as enhanced visual and tactile properties.
It is further a feature and advantage of the invention to provide a method for producing a material having a fine denier component including fine denier fibers of about 3 dpf to about 5 dpf and a large denier component including large denier fibers of about 10 dpf to about 100 dpf.

Cover material with improved fluid handling properties


A packaged die (112) for an integrated circuit (62) that eliminates the wire bonds required in the prior art, and provides integrated circuit packaging while the circuit (62) is still in a wafer format. A wafer substrate (64) on which the integrated circuits (62) have been fabricated is patterned and etched to form signal and ground vias (74, 72) through the substrate (64). A back-side ground plane (82) is deposited in contact with the ground vias (72). A protective layer (90) is formed on the top surface (76) of the substrate (64), and a protective layer (98) is formed on the bottom surface (84) of the substrate (64), where the bottom protective layer (98) fills in removed substrate material between the integrated circuits (62). Vias (106) are formed through the bottom protective layer (98), and the wafer substrate (64) is diced between the integrated circuits (62).

1. Field of the Invention
This invention relates generally to a process for packaging integrated circuits and, more particularly, to a packaging process that eliminates lead frame structures and wire bonds, and allows testing while the integrated circuit is still in wafer format.
2. Discussion of the Related Art
As is well understood in the art, many integrated circuit chips are patterned and formed together on an integrated circuit wafer. The wafer may be 3-15 inches in diameter, and include hundreds or thousands of integrated circuit chips symmetrically disposed in a matrix configuration on the wafer depending on the circuit complexity. Once the integrated circuit chips are fabricated, the wafer is cut between the integrated circuit chips to separate the chips from the wafer. The chips are then tested for performance.
Once the integrated circuit chip is separated from the wafer, it is sometimes packaged in a packaging assembly that provides environmental protection and the like. Generally, the integrated circuit chip is mounted to a metallized ground plane to provide a ground reference and thermal coupling to remove heat from the integrated circuit chip. A lead frame is mounted to the assembly to provide power, signal and ground connections to other circuit elements outside of the package. Wire bonds are used to provide electrical connections between the lead frame and the chip, and between the lead frame and the ground plane. However, the wire bonds cause parasitic inductances and capacitances that compromise performance of the integrated circuit, especially at high frequencies.
FIG. 1 is a cross-sectional view of a packaging assembly 10 for packaging an integrated circuit chip 12 of the type discussed above. The integrated circuit chip 12 is mounted to a back-side ground plane 14 by a thermally and electrically conductive attachment layer 16, such as solder. The ground plane 14 is mounted to a die paddle 18 associated with a lead frame 20. The lead frame 20 includes a plurality of separate leads 24 that are electrically isolated from each other and from the die paddle 18. The leads 24 provide signal and power connections to the integrated circuit chip 12 from other circuit elements and systems. Metal traces 26 are deposited on top of the leads 24 within the packaging assembly 10 to provide a good electrical contact thereto. Signal wire bonds 28 are electrically connected to the traces 26 and to the chip 12 to make electrical connections thereto. Additionally, ground wire bonds 30 are electrically coupled to the ground plane 14 and the traces 26, or the ground plane 14 and the chip 12, as shown. A flowable solder layer 32 is deposited on the bottom surface of the leads 24 and the die paddle 18 to provide good electrical, mechanical and thermal coupling.
A moldable material, such as a plastic compound, is injection molded around the integrated circuit chip 12, the wire bonds 28 and 30 and the lead frame 20 to seal the components and provide a protective cover 36. The packaging assembly 10 is surface mounted to a circuit board (not shown) including other packaging assemblies to form an electrical system. The solder layer 32 is heated so that solder flows up the sides of the leads 24 to make good electrical connection to the circuit board.
The leads 24 of the lead frame 20 of the packaging assembly 10 shown in FIG. 1 extend beyond the sides of the protective cover 36. Thus, the size of the assembly 10 is larger than it needs to be. FIG. 2 is a cross-sectional view of another known packaging assembly 40 that is a variation of the packaging assembly 10 where like elements are identified by the same reference numeral. In this embodiment, the molding forming the cover 36 has been molded to form straight sides with the leads 24 so that when the solder flows up the side of the leads 24, it still makes electrical contact thereto.
In accordance with the teachings of the present invention, a packaging assembly for an integrated circuit is disclosed that eliminates the wire bonds required in the prior art, and provides integrated circuit packaging while the circuit is still in a wafer format. The wafer substrate on which the many integrated circuits have been fabricated is patterned and etched to form signal and power vias through the substrate around an outside periphery of each circuit, and to form ground vias through the substrate beneath the circuits. The combination of a portion of the wafer substrate, the vias and the integrated circuit define an integrated circuit die. Bonding pads are deposited on a top surface and a bottom surface of the wafer substrate that are electrically coupled to the signal vias. A back-side ground plane is provided in electrical contact with the ground vias.
A top protective layer is deposited over all of the integrated circuits, and a photoresist is deposited, patterned and etched on the bottom surface of the wafer substrate so that wafer substrate material can be removed between the dies. A bottom protective layer is then deposited on a bottom surface of the wafer substrate so that it fills the areas between the dies where the substrate material has been removed. The bottom protective layer is then patterned and etched to provide electrical vias therethrough in contact with the back-side metal layer and the signal pads to make electrical contact thereto outside of the packaging assembly. The wafer is then diced along edges of the dies so that the various vias on the sides of the dies are exposed to provide electrical signals to the circuit within the assembly.
Additional advantages and features of the present invention will become apparent from the following description and appended claims, taken in conjunction with the accompanying drawings.


A hybrid switch assembly for a circuit breaker assembly is provided. The circuit breaker assembly includes a housing assembly and an operating mechanism. The housing assembly defines a power electronic switch assembly cavity. A hybrid switch assembly includes a number of conductor assemblies, each conductor assembly including a movable conductor, and a stationary conductor. Further, each movable conductor is structured to move between an open, first position, wherein each movable conductor is spaced from and not in electrical communication with an associated stationary conductor, and a closed, second position, wherein each movable conductor is coupled to and in electrical communication with an associated stationary conductor. A number of the conductor assemblies further include a power electronic switch assembly. Each power electronic switch assembly includes an isolation contact assembly. Each isolation contact assembly is selectively coupled to, and in electronic communication with, the stationary conductor and the movable conductor.

Field of the Invention
The disclosed and claimed concept relates to a hybrid switch assembly and, more particularly, to a hybrid switch assembly including a power electronic switch assembly with an isolation contact assembly that is selectively coupled to, and in electronic communication with, a movable conductor.
Background Information
Hybrid switching technology has its uniqueness and advantages in switching and interruption for applications such as PV, Data Center, Energy Storage, ICT. Due to the increasingly higher DC system voltages, the challenges to interrupt these DC circuits get higher using electromechanical breakers from the size and cost point of view. Hybrid switching technology combining electromechanical contacts and power electronics such as IGBT, SCR, et al. to achieve successful interruption, current carrying with low Joule heating and galvanic isolation; however, this means a second set of contacts needs to be added in series with main switching contacts for isolation. For example, the switching mechanism of the isolation contacts needs to be sized properly to keep the withstand rating of the device; this increases the cost and size of the breaker. The power electronic circuit also needs external power for its operation. Current hybrid switching technology requires additional voltage and current sensors to provide trigger information for power electronic switches. All these add complexity, size and cost to the device, and this complexity makes hybrid breakers more prone to malfunction. These are stated problems.

Hybrid MCCB employing electromechanical contacts and power electronic devices


A ternary CAM memory device is disclosed which comprises a pair of complementary compare lines, a pair of complementary bit lines, and a unique four transistor two capacitor circuit.

The invention relates generally to asemiconductor memory and more particularly to a DRAM CAM device that performs compare operations simultaneously with refresh operations.
A content addressable memory (CAM) is a memory device that accelerates any application requiring fast searches of a database, list, or pattern, such as in database machines, image or voice recognition, or computer and communication networks. CAMs provide benefits over other memory search algorithms by simultaneously comparing the desired information (i.e., data being stored within a given memory location) against the entire list of pre-stored entries. As a result of their unique searching algorithm, CAM devices are frequently employed in network equipment, particularly routers and switches, computer systems and other devices that require rapid content searching.
In order to perform a memory search in the above-identified manner, CAMs are organized differently than other memory devices. For example, data is stored in a random access memory (RAM) in a particular location, called an address. During a memory search on a RAM, the user supplies the address and gets back the data stored in that address (location).
In a CAM, however, data is stored in locations in a somewhat random fashion. The locations can be selected by an address, or the data can be written into a first empty memory location. Once information is stored in a memory location, it is found doing a memory search by comparing every bit in any memory location with every bit of data in a comparand register circuit. When the content stored in the CAM memory location does not match the data placed in the comparand register, the CAM device returns a no match indication. When the content stored in the CAM memory location matches the data placed in the comparand register, the CAM device returns a match indication. In addition, the CAM returns the identification of the address location in which the matching data is stored. Thus, with a CAM, the user supplies the data and gets back an indication of an address where a matching data is stored in the memory.
Locally, CAMs perform an exclusive-NOR (XNOR) function, so that a match is indicated only if both the stored bit and the corresponding input bit are the same state. CAMs are designed so that any number or all of the memory locations may be simultaneously searched for a match with incoming data. In certain cases, data in more than a single location in the memory will match the input data, This condition of multiple simultaneous matches must be detected and reported. However, circuitry for detecting multiple matches in a CAM memory generally is large and complex, and grows exponentially with the number of data words in the memory. Also, switching time is impeded because of the parasitic capacitance associated with the complex logic. Thus, there is a need for a multiple match detector having increased switching speed, yet reduced circuit complexity.
In one aspect, the invention provides a simplified DRAM CAM device having a pair of content capacitors for storing data corresponding to a ternary value of the memory cell; a pair of pass transistors each separately connected to one of the content capacitors and also connected to one of a pair of complementary bitlines, for reading, writing, and refreshing the memory cell; and a pair of logic transistors each separately connected to one of the complementary compare lines and one of the capacitors for performing a comparison of the data on the complementary compare lines with that on the capacitors.
In yet another aspect of the invention, the content capacitors are transistors configured as capacitors.
These and other features and advantages of the invention will be more clearly seen from the following detailed description of the invention which is provided in connection with the accompanying drawings.

High density dynamic ternary-CAM memory architecture


A camera system of the kind arranged to store a lens position obtained at a specific point in time prior to automatic focusing by an automatic focusing device and, when an operation member is operated, to forcedly shift the lens to the stored lens position independently of the automatic focusing action is characterized in that:. when the lens position is stored at the specific point in time, photographing conditions obtained at that point in time are also stored. The camera is set to be in the photographing conditions stored when the lens is shifted to the stored lens position by the operation of the operation member.

1. Field of the Invention
This invention relates to a camera which stores information on photographing conditions such as the distance to an object to be photographed, the mode of exposure, an exposure correction value, etc., and is arranged to perform, when necessary, a photographing operation on the basis of the information stored.
2. Description of the Related Art
Heretofore a camera which is arranged to have the function of the above-stated kind has been provided with a memory for storing the distance to an object to be photographed in addition to an automatic focusing device (hereinafter referred to as an AF device), an automatic exposure device (hereinafter referred to as an AE device), etc.. For example, the object distance obtained for a photographing scene is stored for later use. After that, photographing can be performed for the same specific object without missing any photographic opportunity by calling up the measured distance data stored and by performing only a light measuring action, although distance and light measuring actions must be performed each time for photographing at a different photographing position.
In the case of the above-stated conventional camera, objects other than the specific object must be photographed in a priority mode and at an exposure correction value suited for each of them. Therefore, if the mode and the correction value are not suited for the scene for which the photographing position is stored, it would be difficult to take an optimized exposure picture without readjustment of the priority mode, the control value thereof, and the exposure correction value, even if the distance measuring ring of the photo-taking lens is moved quickly by using the measured distance data stored. This impairs the advantageous feature that a photographing operation can be speedily carried out by virtue of the stored position of the distance measuring ring.
Further, if the camera is not arranged to have any absolute distance information for moving the distance measuring ring of the photo-taking lens, and if a reproducing action is performed for photographing on the basis of a previously stored specific object position after one photo taking lens is interchanged with another, the action would be incorrectly performed thereby making accurate focusing impossible.


There is provided a method for producing a nonwoven fabric that can produce a nonwoven fabric having high strength, high bulk and softness. The method for producing a nonwoven fabric according to the invention comprises a step of supplying a water-containing paper-making material onto a support to form a paper layer 21 on the support, a step of injecting a high-pressure water jet stream onto the paper layer 21 from a high-pressure water jet stream nozzle 12 provided above the support, a step of injecting high-pressure steam onto the paper layer 21 on which the high-pressure water jet stream has been injected, from a steam nozzle 14 provided above the support, and a step of drying the paper layer on which the high-pressure steam has been injected.

As prior art, there is known a method for producing a high-bulk sheet wherein a fiber suspension containing an added wet paper strength agent is supplied from a paper-making material supply head onto a paper layer-forming belt to accumulate fibers on the paper layer-forming belt, a wet fiber sheet is formed, a suction box is used for dewatering of the fiber sheet, and then steam is injected from a steam-injecting nozzle onto the fiber sheet to impart a prescribed pattern to the fiber sheet (for example, Japanese Unexamined Patent Publication No. 2000-34690). By this method for producing a high-bulk sheet, it is possible to produce a high-bulk sheet with large thickness, high absorption, excellent softness and suitable sturdiness.

Manufacturing method for nonwoven fabric


A plurality of resonators are embedded in a base material for use in applications in the printing industry. The base material including the resonators can be used in printing press applications, finishing applications, packaging applications, distribution applications, and downstream applications. The base material can include paper, ink, coatings, polymers, composites, adhesives, metal, or a combination of any of these materials.

In the printing industry, keeping track of individual paper, bound books such as magazines and catalogs, bundles, pallets, and packages is difficult, time consuming and expensive. Optical bar code systems have been utilized in the printing industry; however, this technology operates at short range and requires line of sight detection. Magnetic systems also have been utilized in the printing industry; however, this technology requires contact with magnetic media and a prescribed orientation of the magnetic material. Active RF tag technology is bulky requiring a battery or antenna to power the device and a chip for intelligence and data storage, both assembled together and encased in a material such as plastic. The size and expense of these active RF tags limit their use.


A laundry washing machine comprising: a cabinet; a tub inside the cabinet and comprising a first and second shells fixed together and defining a sump at a bottom region of the tub; a rotatable drum in the tub; a draining circuit fluidly connected to the sump for draining liquid from the bottom of the latter; a level detection device configured for detecting the level of liquid within the tub and comprising an air chamber having a liquid inlet provided at the sump and in fluid communication with the internal of the latter; and a recirculation circuit configured for withdrawing liquid from the tub and to re-admit such a liquid into the tub through an outlet opening positioned in the sump. The outlet opening of the recirculation circuit and the liquid inlet of the level detection device are located one on the first shell and the other on second shell.

Nowadays washing machines, both "simple" washing machines (i.e. washing machines which can only wash and rinse the laundry) and washing-drying machines (or "washer-driers", i.e. washing machines which can also dry the laundry), usually comprise an external casing (called also cabinet) housing a washing tub (called also tub), typically suspended to the cabinet through springs and dampers, and in which a washing drum (called also drum) is rotatably contained.
A loading/unloading door, typically hinged to the cabinet, ensures access to the tub and the drum.
In some known laundry washing machines, the tub comprises (e.g. is composed of) two shells, which are connected to one another (e.g. by welding) in such a way that the connection is watertight; the shells are so shaped to define, at a bottom region of the tub, a sump, which is fluidly connected to a draining circuit for draining liquid from the bottom of the latter.
Known laundry washing machines comprise a detergent supply unit and a water inlet circuit for the introduction of water and washing/rinsing products (i.e. detergent, softener, etc.) into the tub.
Known laundry washing machines typically comprise a level detection device, configured for detecting the level of liquid within the tub; the liquid level detected by this device is used, for example, to correctly activate the water inlet circuit during the washing cycle.
Level detection devices of known type typically comprise a pressure sensor, or pressure switch, which communicates with an air volume enclosed in an air chamber via a narrow conduit. The air chamber is typically arranged in the bottom part of the tub and is in fluid communication with the internal of the latter by a liquid inlet; the air volume enclosed above the liquid entering the air chamber through the liquid inlet is therefore subjected to a pressure which is sensed by the pressure sensor, and then translated into a measure of the liquid level in the tub.
Some known laundry washing machines are also provided with a recirculation circuit configured for withdrawing liquid from the tub and to re-admit such a liquid into the tub through an outlet opening positioned in the sump; in this way such a liquid, which is typically water containing a washing and/or rinsing additive (e.g. detergent and/or softener) can be effectively mixed, so as to effectively dilute the washing and/or rinsing additive in the water.
Known laundry washing machines provided with both above described level detection device and recirculation circuit have however some drawbacks; in fact, it is known that laundry washing machines have strict dimensional constraints, due to modularity of the appliance cabinet and its footprint, in particular fixing the maximum external dimensions of the cabinet, that impose restrictions to the positioning of the various components within the cabinet in order to match the external dimensions constraints. In particular, the recirculation circuit and the level detection device comprise many components (pump, ducts sensors, etc.) and therefore they take up much space within the cabinet, which makes their positioning and assembly much cumbersome.
In such known laundry washing machines, therefore, in particular in order to fulfill external dimensions constraints, there is the need of finding a way for optimizing the positioning of the recirculation circuit and the level detection device within the cabinet.


A method for dehydration and critical point drying of a sample in a single chamber is introduced, comprising the steps of (a) dehydrating the sample by replacing water by an intermediate fluid, (b) replacing the intermediate fluid by a transitional fluid, (c) pressurising the transitional fluid to or beyond its critical pressure and/or heating the transitional fluid (4 to or beyond its critical temperature, and (d) in response to gradually releasing the pressure, letting the transitional fluid gasify and escape from the sample. In step (a) and/or step (b), a ratio of the fluid to-be-replaced to the replacing fluid is measured and used to control a supply of the replacing fluid.

Critical point drying is a process to remove liquid, e.g. water, in a controlled way from a sample. It is commonly used to remove water, e.g. from biological samples in the preparation for scanning electron microscopy and in the production of microelectromechanical systems (MEMS).
Critical point drying exploits the property that fluids exhibit a supercritical state if temperature and pressure are above the critical point, where no phase boundary between liquid and gas exists. If the transition from liquid to gas is performed via the supercritical regime, damaging or a collapse of the delicate sample is avoided due to the absence of detrimental surface tension of the liquid.
For water the critical point is at a temperature of 374° C. and a pressure of 22.06 MPa. The high critical temperature makes it inconvenient to directly perform critical point drying on an aqueous sample since it would cause heat damage. Hence a transitional fluid is used, usually liquid carbon dioxide (CO2) which has a critical temperature of 31° C. and a critical pressure of 7.39 MPa. However, CO2 is not miscible with water, therefore an intermediate fluid is used in an intermediate step to dehydrate the sample before performing critical point drying with CO2. Commonly used intermediate fluids are acetone, ethanol, isopropanol, amyl acetate, or a solution of one of those in water.
Typically a critical point drying process contains the following steps:                Transporting the dehydrated samples in the intermediate fluid into a chamber under ambient pressure. The chamber may partly be filled with intermediate fluid to avoid the surface of the sample becoming touch dry.        Replacing the intermediate fluid in the chamber with the transitional fluid.        Transferring the transitional fluid from liquid to supercritical state by heating and pressurising the chamber. Meanwhile a part of the transitional fluid is drained from the chamber to avoid excessive overpressure.        Transferring the supercritical transitional fluid to the gaseous state by slowly depressurising the chamber and letting the gas escape while heating to avoid recondensation of the transitional fluid. Finally the chamber is at ambient pressure, and the sample can be removed.
With common systems the step of dehydrating the sample by means of the intermediate fluid is performed in a separate vessel, mostly manually, before transporting the sample into the chamber. The amount of intermediate fluid and time is chosen according to empirical values, which leads to a high consumption of intermediate fluid and a long process duration in order to make sure that the sample is sufficiently dehydrated.
After dehydration the sample is manually transferred to the chamber. Since the sample should not be in contact with surrounding air, careful handling has to be applied with dedicated transport vessels.
In order to ensure sufficient replacement of the intermediate fluid by the transitional fluid, large amounts of transitional fluid are flowed through the chamber, and additional rest periods may be interposed to improve diffusion of the intermediate fluid out of the sample. The parameters of this process are again chosen according to empirical values and lead to a high consumption of transitional fluid and a long process duration.

Method for dehydration and critical point drying

Abstract: The method reduces consumption of intermediate fluid and/or transitional fluid, making the process more efficient in terms of duration and user interaction while ensuring a high degree of dryness and the integrity of the sample.


An input node is configured to receive a supply signal which may be of a first polarity or a second polarity opposite the first polarity. A high input current circuit couples the input node to an output node through at least one power transistor having a control electrode. A low input current circuit couples a supply current from the input node to control circuit configured to control the power transistor. A circuit is provided to detect polarity reversal with respect to the supply signal. A protection circuit for the low input current circuit operates to decouple the control circuit from the input node if the supply signal has the second polarity. A protection circuit for the high input current circuit operates to short-circuit the control electrode of the power transistor to the current path provided by the power transistor between the input node and the output node.

Protection of electronic circuits from reverse polarity supply voltage is a desirable feature for users of devices such as, for instance, e-fuses, low-dropout regulators (LDO's) and so on.
Electronic systems may be protected from reverse polarity input supply, as caused by mis-wiring, for instance, by adding a power component such as a diode in series with the supply line. This additional discrete component may undesirably add to the cost of the system.
Other solutions, such as the industrial e-fuse with integrated reverse input polarity protection available as TPS2660x from Texas Instruments are capable of withstanding positive and negative supply voltages up to ±60 V and protecting an associated load correspondingly. The related architecture is based on a dedicated pin (RTN) operating as a reference for internal control circuits in the device. Protection is provided by applying a reverse polarity to the RTN pin with reference to a GND terminal. Making RTN negative like the input polarity facilitates managing reverse supply without damaging the control circuit.
This solution involves a fairly complex supply management and the availability of a negative reference on the board.

Supply protection circuit that protects power transistor from a supply signal of an incorrect polarity


The present suitcases only provide the service of carrying clothing and cosmetics. This Invention would carry clothing, cosmetics and bed.

In accordance with an embodiment of the present Invention relates to a modified suitcase incorporating a compartment from which would extend a lightweight telescopic cot. There is a suitcase with a built in collapsible cot structure in the back comprising a fabric Web, a frame, and folding legs. When set up, the cot structure provides for a person to lie down or sit on top of the fabric. There is a divider, where divider separates the luggage first compartment and cot in second compartment in one particular embodiment. The lugcot modification would ensure a place to set or sleep, was always available and the traveler did not have to rest upon the floor or ground. Not only will present invention benefit traveler, it will benefit camper for backpacks, military backpacks, forest fire fighter's backpacks.
The present suitcases only provide the service of carrying clothing and cosmetics. This Invention would carry clothing, cosmetics and bed.


A circuit includes a first ring oscillator with a plurality of stages, each coupled via a voltage follower cross-coupling to a plurality of stages of a second ring oscillator. Further ring oscillators may be coupled to the first ring oscillator and the second ring oscillator. Additionally, the voltage follower cross-coupling for each of the stages may include one or more first voltage follower having a first strength, and one or more second voltage follower having a second strength different than the first strength.

In recent wireline communication designs, data rates higher than about 50 Gbps are becoming common even without the utilization of multi-level signaling (e.g., PAM-4). A reliable clock source may provide greater than about 25 GHz differential or greater than about 12.5 GHz quadrature timing. For low-power applications, feed-forward clocking is a promising technology, which utilizes both I and Q clock signals from the source. This requirement may effectively double the frequency target of the oscillator. For example, an about 25 Gbps system may utilize an about 25 GHz differential ring oscillator, then generate about 12.5 GHz quadrature clocks using a clock divider. In a similar link design potentially running at about 50 Gbps, the equivalent frequency of the oscillator would be at least about 50 GHz, which is impractical for a ring oscillator. An example of a ring oscillator is a device comprising an odd number of NOT gates in a ring, whose output oscillates between two voltage levels, representing true and false.
Another design challenge in high-speed clocking is the phase interpolator circuit. In feed-forward clocking systems, the phase interpolator circuit is important for performance characterization. The phase interpolator circuit is preferably continuously operational to compensate the delay mismatch between data lanes (DQs) and strobe lane (DQ-S) arising from loading mismatches at both the signal transmitter circuit and the signal receiver circuit. Phase interpolator circuits tend to be expensive in both power consumption and circuit area, especially when good resolution is required.
A conventional three-stage differential oscillator 100 utilizes inverter-based cross-coupling as shown in FIG. 1, which correlates the signal phase between opposite circuit nodes (e.g., 0 and 180 degrees). This cross-coupling works well when there is negligible signal delay between the inverters' inputs and outputs. However, in practice, the inverter delay may cause driving strength contention between the main loop circuit and coupling elements and slow down the oscillation frequency by about 30-40% as compared to single ring oscillator.
The use of inverter-based cross-coupling in conventional differential oscillators (FIG. 1) thus incurs an about 30-40% oscillation frequency reduction compared to a single three-phase ring oscillator. Normally, the benefit from inverter-based cross-coupling is better common-mode voltage definition, for example, they can be applied as differential clock sources. But a ring oscillator with an odd number of stages generally can intrinsically determine the common-mode. Thus, inverter-based cross-coupling in oscillators provides signal phase correlation but in an inefficient manner.

Voltage-follower based cross-coupling oscillators with embedded phase-interpolation function


The present invention generally relates to implantable medical devices and more particularly to various means for ultrasonically welding, swaging or staking various components in an implantable medical device, most preferably by employing appropriately configured covers or lids. Covers or lids are attached to header or connector modules mounted on an hermetically enclosed and sealed enclosure, where the connector or header module and enclosure comprise an implantable medical device. The covers or lids preferably trap or otherwise secure any of a number of various connector or header module components within the header or connector modules. Examples of such trapped or secured components include grommets, set screw connector blocks, seals, feedthrough wires, multi-beam contacts, electrical contacts, antennas, radio-opaque markers, connector ribbons and the like.

The earliest implantable medical devices, e.g., implantable cardiac pacemakers and other body tissue stimulating devices, were formed of an implantable pulse generator (IPG) and a set of electrical leads attached between the IPG and heart or body tissue to be paced or stimulated. Typically, the IPG electrical circuit was powered either by Hg-Zn batteries or by induction of energy transmitted transcutaneously from a skin surface RF power generator and supplied electrical pacing or stimulating pulses to the leads. The IPG batteries and circuits were encapsulated within an epoxy compound partly for ease of manufacture and to allow hydrogen emitted by the Hg-Zn batteries to escape. Electrical connector pins and rings, if present, were initially permanently attached to the circuits. Other early implantable medical devices, e.g. implantable monitors and cochlear implants or the like were also formed in somewhat the same manner.
Such early implantable cardiac pacemakers suffered very short useful lives due to moisture ingress through the epoxy and causing electrical dendritic growth across, and shorting of, adjacent points of the circuit, battery terminals, or discrete transistor terminals. In addition, pacing leads frequently failed due to conductor stress fractures, and batteries depleted prematurely for a variety of reasons.
In the 1960's, IPG connector assemblies were formed integrally with other IPG circuit components and embedded in an epoxy housing to enable attachment of a chosen lead to the IPG circuit for initial implant or defective lead replacement purposes. These integrally formed connector assemblies typically comprised at least one metal, electrical connector block encapsulated therein that were aligned in relation to an elongated lead end receptacle for receiving the proximal lead end. Each connector block was formed to have a bore to receive the lead connector pin or ring, depending on the type of lead intended to be used, and a threaded cross bore receiving a trapped set screw. The electrical connections in connector blocks were typically directly attached to IPG circuits. A silicone rubber suture boot was placed in a mold in alignment with an elongated receptacle. The entire IPG, including connector assembly components, was then encapsulated in epoxy.
In use, a proximal lead connector end was inserted into the appropriate lead connector receptacle until the lead connector pin or ring was received in the bore of the connector block. A set screw was then tightened by a hex wrench to establish firm electrical and mechanical connections and the opening through the molded epoxy housing to access the set screw was sealed. Sutures were tied around the suture boot for sealing engagement against the lead body.
Beginning in the 1970s, hermetically sealed lithium batteries and miniaturized digital and analog integrated circuits (ICs) have been used in implantable medical devices, particularly for implantable cardiac pacemaker and nerve stimulation IPGs. Integrated circuits, batteries and other components were enclosed in hermetically sealed metallic enclosures or "cans" separated from the connector assembly components. Electrical connection between connector blocks and other components of the connector assembly was generally accomplished by electrical feedthroughs supporting feedthrough pins extending through the hermetically sealed can.
Lead connector assembly components external to the hermetically sealed enclosure are still to this date attached to an attachment surface thereof using an in situ molding process to seal the connector assembly components and form the receptacle for a lead or catheter proximal end, etc. For example, in the formation of a lead connector assembly for a cardiac pacemaker IPG, the connector blocks and feedthrough pins are welded together and laid out in a mold with respect to any other associated components and mold plugs. An encapsulating compound is injected into the mold to form the connector header assembly molded to the IPG attachment surface as described, for example, in U.S. Pat. No. 4,041,956, the disclosure of which is hereby incorporated by reference herein in its entirety. This approach is time consuming and not terribly precise. If the resulting connector header assembly fails to meet dimensional tolerances or other quality requirements, it is difficult to rework the IPG.
In 1979 the MEDTRONIC.RTM. SPECTRAX.RTM. cardiac pacemaker IPGs were introduced having the digital and analog or hybrid ICs and lithium batteries enclosed within a hermetically sealed titanium enclosure having feedthroughs extending through an enclosure attachment surface thereof. Assembly of these components and other details are disclosed in U.S. Pat. Nos. 4,142,532 and 4,182,345, hereby incorporated by reference herein in their respective entireties.
The lead connector assembly, in this case and as used in IPG models to the present time by Medtronic, Inc., is manufactured as a separate pre-formed connector header module that encloses connector components and is attached to an enclosure attachment surface of the hermetically sealed enclosure and to the feedthrough pins. The connector header module is molded of a thermoplastic elastomer such as medical grade polyurethane, has an outer module surface and a number of receptacles and channels disposed within it that in some instances are accessible through windows, channels or recesses extending outwardly to the module surface. The connector header module receives the electrical connector blocks)in connector block receptacles such that the connector block bores are aligned with elongated lead connector receptacles for receiving the proximal lead connector end assemblies. In a typical design, each such connector block is formed with a threaded cross bore receiving a trapped set screw as described above. Each set screw of each connector block in a connector block receptacle is also aligned with a septum receptacle for receiving a silicone rubber set screw septum.
A pre-formed connector header module is generally formed with pin channels for directing the feedthrough pins into contact with the respective connector blocks and with windows to allow the connector blocks and septums to be inserted into their respective receptacles. In each case, the connector block receptacle window or a further window to the module surface is provided for allowing the feedthrough pin end to be welded to the connector block. The windows and pin channels are typically back filled with a medical grade silicone adhesive after the welding step and attachment of the connector header module to the hermetically sealed enclosure.
The receptacle for the connector block and the connector block itself most preferably have fight dimensional tolerances to permit precise alignment of the connector block bore with the lead connector receptacle. In one approach, the connector block receptacle opening dimensions are reduced and the opening edge thereof shaped so that the connector block stretches the opening edge as it is inserted into the connector block receptacle. In other cardiac pacemaker IPGs, each connector block is inserted into a connector block receptacle and ultrasonic energy is applied to the edge of the connector block window to melt it over and tamp it against the exposed surface of the connector block. This ultrasonic tamping technique of dissimilar material parts is similar to that shown in the article entitled "Ultrasonic Joining of Moulded Parts and Semi-Finished Parts of Thermo-Plastic Polymers in Mass Production-Forming with Ultrasound," Staking, Swaging and Tamping (Guideline DVS 2216, Part 3, 1992), Welding in the World, Le Soudage Dans Le Monde, Vol. 31, No. 3, pp. 205-207 (1993), the disclosure of which is hereby incorporated by reference herein in its entirety.
As a general rule, a connector header module formed as described above must have tight dimensional tolerances and remain dimensionally stable over long periods of time in the hostile environment found within the human body. Any substantial initial or time-induced misalignment of the lead connector receptacle bores extending through the molded module housing and the connector block bores can make initial attachment or removal and replacement of a lead connector end impossible or unreliable. During the attachment of the connector header module to the hermetically sealed enclosure, medical grade adhesive is usually employed to attach the module attachment surface to the enclosure attachment surface. While the adhesive cures, it is necessary to ensure that the attachment surfaces are not disturbed.
Some workers in the field have proposed employing mechanical attachment mechanisms as a substitute for, or in addition to, the use of the medical grade adhesive for attaching surfaces to one another. Mechanical attachment mechanisms proposed in the art for use with or without medical grade adhesive are described in U.S. Pat. Nos. 4,142,532 and 4,182,345, both incorporated herein by reference in their respective entireties. While the approaches described in those patents have merit, they require the use of additional precision piece parts and assembly steps that may add to the cost and time required to assemble the connector header module and connect it to the hermetically sealed enclosure.
Finally, it should be noted that it has been recently proposed to form the connector header module as part of a shroud surrounding and adhering to the rim of the hermetically sealed enclosure in order to simplify the assembly by reducing the number of parts, assembly steps and dimensional tolerance requirements. Such configurations are shown in U.S. Pat. Nos. 5,535,097, 5,522,861, 5,456,698 and 5,431,695, all incorporated herein by reference in their respective entireties. In such configurations, the shroud is preferably formed of a flexible silicon rubber and pacing leads may be attached and replaced in conventional fashion. The use of silicone rubber presents certain difficulties and disadvantages, however, most of which relate to dimensional instability and lack of rigidity, lack of an aesthetically pleasing physical appearance and potential discoloration of the silicone rubber during storage and sterilization.

Method of making ultrasonically welded, staked of swaged components in an implantable medical device


An anchor winch system includes a support arm, an end effector, a guide channel, a winch, a cable and an anchor. The anchor winch system enables a user to deploy an anchor that is stored within the C or Z channels of a pontoon or tritoon boat. The support arm is mounted along the C or Z channel and the end effector is mounted onto an end of the support arm. The end effector is a holding apparatus that retains the anchor in a stowed position when not deployed. The guide channel traverses through the support arm, and the cable is threaded through the guide channel. The winch is tethered to one end of the cable and the anchor is tethered to the opposite end. Thus, the winch is able to deploy or retract the anchor by paying out or reeling in the cable.

Pontoon and tritoon boats frequently need to be anchored in place. Because of this requirement, boaters have come up with multiple solutions for holding their boats in place. These solutions include anchors attached to chains and ropes. Some systems even employ mechanical assistance to draw up the anchor once deployed. However, these systems are frequently exposed to the elements and become damaged. Additionally, these anchoring systems are often bulky and take up space on the deck.
The present invention is an anchor winch system that addresses these shortcomings. To achieve this functionality, the present invention employs a system that may be integrated into the C or Z Channel crossmembers of the boat. This protects the winch and other components from exposure to conditions at sea. Further, the present invention may be mounted beneath the boat to save deck space. Further, the present invention provides a system for mounting a waterproof drum anchor winch between the pontoons of a pontoon or tritoon boat. The present invention enables a user to retrofit the pontoon or tritoon boat with an out of the way anchoring system that does not clutter the deck of the boat. In these embodiments, the present invention can be encased in a waterproof housing that limits exposure to water and other hazards in the environment. The present invention makes use of an end effector to retain the anchor in a stowed position. Thus, limiting the chance that the anchor will be dislodged inadvertently. Further, the present invention provides a system for mounting a waterproof drum anchor winch between the pontoons of a pontoon or tritoon boat. The present invention enables a user to retrofit the pontoon boat with an out of the way anchoring system that does not clutter the deck of the boat.


A fixing device including: a fixing member that heats toner image and fixes it onto a recording material; a pressure member that forms a nip that presses the recording material against the fixing member; a first air separating section that blows air against the fixing member and separates the recording sheet from the fixing member; and a separation claw that separates the recording material from the pressure member, wherein a tip of the separation claw contacts the pressure member at a position which is downstream, in a direction of movement of a surface of the pressure member, of a peak of an air blast pressure distribution on a surface of the pressure member, and wherein the air blast pressure distribution is formed by air blown against the pressure member which is caused by the air blown by the first air separating section against the fixing member.

1. Field of the Invention
The present invention relates to image forming apparatuses of the electro-photographic type, and in particular, to fixing devices that fix toner images.
2. Description of Related Art
In fixing devices of image forming apparatuses of the electro-photographic type, as a section for separating the recording material from the fixing member after fixing, there are those that use separation claws and those that use air separating section. As an example of such separating section, in Unexamined Japanese Utility Model Application Publication No. Sho 63 (1988)-140571 it has been proposed that not only the recording material is separated from the fixing member using a first separating section, but also a second separating section that aids the separation by the first separating section. An air separating section is used as the second separating section.
In the separation using a separation claw, there are problems such as the fixing member being scratched by the separation claw, etc. Even if a separation using air is used in combination as in Unexamined Japanese Utility Model Application Publication No. Sho 63 (1988)-140571, it is difficult to prevent the fixing member from getting scratched by the separation claw.
Because of this, the present inventors carried out investigations of the air separating section that separates a recording material from a fixing member by blowing air at the fixing member.
When separation using an air separating section was made, although good separation was made of recording material having a thicknesses more than common sheets such as printing paper or copying paper, the following problems occurred in the case of thin sheets with a basis weight of 60 g/m2 or less.
When separating a recording material from a fixing member using an air separating section, during the separation of recording material with low rigidity such as thin sheets, it becomes necessary to increase the pressure of the air that is blown towards the fixing member. However, it becomes easy for the recording sheet that has been separated from the fixing member using a high pressure air blast to be pressed towards the pressure member side and get adhered to the pressure member. It was possible to avoid the adhering to the pressure member by providing a separation claw on the side of the pressure member. In this manner, by separating the recording sheet from the fixing member using an air separating section, and separating the recording sheet from the pressure member using a separation claw, it becomes possible to separate a thin sheet definitely from both the fixing member and the pressure member and to convey it smoothly inside the fixing device.
However, when a separation claw is provided on the side of the pressure member, it was found that string shaped undulations are formed on the recording material by the separation claw thereby lowering the quality of the copy or printed matter. The string shaped undulations, in addition, have a bad effect on the conveying of the recording material inside a finishing apparatus connected to the image forming apparatus.
The string shaped undulations are explained using FIG. 1.
In FIG. 1, the white part indicates the ridge parts PA, and the hatched part indicates the valley parts PB.
The ridge part indicated by PA is the part of the recording material P that has passed a separation claw 77, and the valley part indicated by PB is the part of the recording material P that has passed between a separation claw 77 and a separation claw 77.
The recording sheet P passes over the position of a separation claw 77 while being pushed by air. Therefore, in the gap formed between a plurality of separation claws 77, the recording sheet P is pushed to a position that is lower than the separation claws 77. As a result, a high-low difference is created between the position of a separation claw 77 and the position of the gap between separation claws 77, and hence string shaped undulations are formed in the recording sheet P as is shown in FIG. 1.
The string shaped undulations of the recording sheet P formed in this manner result in lowering the quality of the printed matter in which images have been formed. Further, when a finishing apparatus has been connected to the image forming apparatus, the conveying inside a finishing apparatus connected to the image forming apparatus of the recording material in which the string shaped undulations shown in FIG. 1 is not carried out smoothly, and it becomes easy for conveying defects to occur such as jamming, etc.

Fixing device including an air separation section

Konica Minolta Business Technologies, Inc.


In an approach for calibrating a delay line having a plurality of taps, a first clock signal is input to the delay line. A second clock signal is input to a reference circuit having a plurality of taps. In response to determining that output signals of selected taps of the delay line and reference circuit do not align, a next tap of the reference circuit is selected, to determine whether or not the output signals align. In response to determining that the output signals align, reference tap data indicative of the current reference tap is stored in association with a delay tap number of the current delay tap. A next tap of the delay line is selected to determine whether or not the output signals align.

Delay lines may be used for adjusting the timing of various signals in an electronic system. A delay line may have multiple serially connected delay elements with an input signal being delayed by each delay element. The outputs of the delay elements may be tapped to provide the input signal delayed by different amounts. The taps of the delay line may be selectable such that one of the taps is selected to provide the input signal delayed by a desired amount.
In one application, a delay line may be used to adjust a clock signal for reliably sampling a data signal. The delay line may cover the entire eye pattern of a data signal so that one of the taps may be selected to satisfy the setup and hold times for sampling the data signal. Determining which tap to use to sample the data signal may be problematic because of non-linearity of the delay line. That is, each delay element of the delay line may introduce a different amount of delay. In some systems, delay lines may be specifically designed to reduce the non-linearity. However, such delay lines tend to be expensive in terms of circuit resources.

Delay line calibration circuit and method


An electrochemical cell 10 is provided that includes first and second electrodes 13, 15, an electrolyte medium 17 in electrolytic communication with the first and second electrodes 13, 15, a chemical substance capable of undergoing an electrochemical reaction, and a voltage source 19 in electrolytic communication with the first and second electrodes 13, 15. The first electrode 13 includes a layer of an active catalyst material 25, and graphene coating 27 at least partially covering the layer of the active catalyst material 25. Methods for making and using the graphene coated electrode are further provided.

Electrodes are used in many applications and processes including, but not limited to, sensor applications, fuel cell applications, electrolyzer applications, electrosynthesis applications, battery applications, and hydrolysis processes, for example. However, many electrodes are hampered by surface blockage of the catalyst as well as transport of the chemical species to the active catalytic surface. Ideally, high concentration of reactants at the catalyst surface is desired with fast concomitant removal of the products. Additionally, corrosion is another common problem encountered in many applications. Accordingly, improved electrodes are needed.

Electrochemical cell containing a graphene coated electrode


A method and device for testing an electrical circuit, which do not require a thorough electrical circuit simulation but reliably identifying circuit faults. Preferred embodiments generate a fault signal that indicates that a given state of the circuit, which is defined by an electrical state variable, could occur in an electrical circuit. Generally, electrical components are individually treated as short-circuited or non-conducting regarding each pair of connections of the components. An electrical state variable is permanently allocated to at least one network node or a connecting pin of the electrical circuit. Electrical state variables of the network nodes and connecting pins of the components that are to be treated as short-circuited are allocated to each network node and each connecting pin. An assessment is made at least based on the allocated state variables as to whether the given circuit state can occur.

Faults or weak points in electrical circuits may involve individual components in an electrical circuit having an excessive voltage, or a voltage with the wrong polarity applied to it, for example. The maximum voltages, which are permitted to be applied to the components in this case are dependent, inter alia, on the respective component type. By way of example, the maximum permissible voltage on a "thin oxide" field effect transistor is lower than that on a "thick oxide" field effect transistor.
It should also be remembered that in a complex electrical circuit—that is to say a network with different passive and active components (resistors, transistors, etc.), for example—the voltage potential on a component is dependent on the switching states of the respective upstream components. It is, therefore, also generally necessary to take into account the switching states of the components.
An electrical circuit is normally tested by performing circuit simulations in which the electrical response of the circuit is simulated. Although circuit simulations are useful for detecting the weak points in the design of the circuit, they have the drawback that the circuit response is examined only for the respective prescribed stimulus vector or a prescribed set of input voltages or other parameters (e.g., currents, temperature, etc.). A fault can, therefore, be found only if the stimulus vector or the set of parameters challenges the circuit in a way that produces and reveals a fault that the circuit contains. A further drawback of more detailed or more elaborate circuit simulations is relatively long computation times.

Device and method for testing an electrical circuit


An electroacoustic piezoelectric transducer comprises a concave diaphragm and at least two planar bimorph elements having different respective resonance frequency characteristics coupled to the diaphragm. The bimorph elements may comprise larger and smaller bimorph elements providing frequency responses in lower and higher frequency ranges respectively, and are preferably directly connected to the inner concave surface of the diaphragm.

The present invention relates generally to electroacoustic transducers and, more particularly, to an electroacoustic transducer of the type driven by or driving a piezoelectric element that bends in response to electrical energy applied across it, or which produces electrical energy in response to bending or warping.
Reference is made to the applicant's U.S. Pat. No. 4,845,776 issued July 4, 1989, the disclosure of which is hereby incorporated by reference, with respect to the description therein of such electroacoustic piezoelectric transducers.
A piezoelectric element of the type conventionally used in such electroacoustic transducers is referred to herein as a bimorph element and comprises two piezoelectric wafers having outer electrodes and which are sandwiched over a conductive metallic interlayer which forms an electrode intermediate the two wafers. The bimorph element has a substantially planar configuration and is relatively thin between its outer electrodes with respect to its lateral dimension thereby permitting the bimorph to flex along its long dimensions or diameters. When an electrical signal is positive on the outer electrodes with respect to the intermediate electrode, the center of the bimorph element flexes in one direction. Reversing the electric field polarity causes the bimorph to flex in the opposite direction. Impressing an alternating voltage across the electrodes causes the bimorph element to oscillate.
Electroacoustic piezoelectric transducers are known which convert alternating electric voltage to sound, thereby acting as loudspeakers. In a loudspeaker of this type, a bimorph element is mounted to a concave diaphragm and is electrically coupled to an alternating audio voltage source as described above. As the bimorph element vibrates or oscillates, the diaphragm is caused to vibrate resulting in compressional airwaves transmitting audio vibrations in the usual manner.
The operating range of electroacoustic piezoelectric transducers varies as a function of several variables, including among other things, the physical characteristics of the diaphragm, the arrangement by which the bimorph element is coupled to the diaphragm, and the vibrational characteristics of the particular bimorph element that drives the system (in the case of a loudspeaker). For a particular transducer construction, the frequency response of the transducer depends on the resonance vibration characteristics of the bimorph element. The resonance frequencies of the bimorph element provides an indication of the operating range of a transducer using such an element. Since the bimorph element generally has a high resonance frequency, it is possible to use a large bimorph element for a range of frequencies. Although the frequency response of a transducer can be improved by inserting a coil or inductance in series with the bimorph element and tuning the reactances to the center frequency of the desired bandwidth, the operating range of an electroacoustic piezoelectric transducer is generally limited by the vibrational characteristics of the bimorph element which is coupled to the diaphragm.

Electroacoustic piezoelectric transducer having a broad operating range


A method and apparatus for treating raw influent water to remove particles, algae and toxic chemicals from the water. Basically, air is dissolved in recirculated water under high pressure in an air contactor unit, the air saturated water is intimately mixed with the raw, particle bearing, water in a particle mixing system, and the water, particle and air mixture is passed through an air bubble separator wherein bubbles formed when the pressure on air saturated water is reduced carry away toxic gases and particulate material. If desired for further cleaning the water can be sent through a second series of air contactor, particle mixer and air bubble separation, but with a gas comprising ozone to further remove suspended particles and non-volatile dissolved organic matter. In order to improve mixing of the particles and the air saturated water passing through tubes, preferably a pattern of dimples is formed on at least part of the interior wall of the tubes. Upon completion of the process the water is ready for use or for further filtration in a conventional filtration plant.

Water supplies for domestic drinking water, process water for chemical plants or other liquids are often contaminated with a variety of contaminants, such as toxic chemicals, algae, dissolved oil and various organic and inorganic particles of various sizes. These contaminants must be removed in a reliable, cost effective manner.
Many older water treatment plants use gravitational separation methods, typically in sedimentation systems or dual-media sand filtration systems that may not be acceptable under the newer water quality standards. In some cases, these systems can meet the standards through the use of properly mixed polymer chemical filter aids. The required expensive and complex polymer chemical mixing equipment requires constant attention, since the amount of the chemicals being added to raw water must be frequently readjusted to match the continually changing chemistry of the water being filtered. Slow sand filters require a considerable investment, but generally can be operate for longer periods without cleaning. Unfortunately, even with pre-treatment, both dual-media and slow sand filters fail to meet water quality standards for hours or several days after each backwash cleaning.
Ordinary chemical flocculation and sedimentation processes do not prevent toxic chemicals, pesticides and algae from passing through the ordinary filter bed. If algae spores are present when chlorine is added, toxic disinfection byproducts are formed, which is highly undesirable and a violation of the USEPA Safe Drinking Water Act. The inability of older municipal filtrations systems to remove algae is apparent in the lack of clarity found when a swimming pool is filled with "clean" tap water. Most pool contractors have to shock tap water with large doses of chlorine chemical pool oxidizer to achieve the desired clear pool water appearance.
Particulate material has also been removed from liquids by floatation, another gravitational method, in which bubbles of a gas, such as air or oxygen, are introduced into the lower levels of the liquid and float to the top, carrying fine particles with them. Various chemical additives, such as flocculation aids, typically alum polymers, are required with these systems. Flotation is a gravitational method because the rise of bubbles is due to the gravitational acceleration acting on the mass of the liquid in accordance with the basic force equals mass time acceleration relationship. A force balance relative to a pocket of gas phase within liquid (a bubble), where the mass of the bubble is its volume times its density, shows that the bubble must rise to find equilibrium, because the density of a gas is generally less than that of a liquid. Large flotation tanks are required to allow adequate time for air bubbles to reach the surface.
Failure to remove algae prior to filtration also leads to clogged filters, increases filter operation costs and wastes water required for frequent filter cleaning cycles. The use of flocculation promoting chemicals increases the volume of sludge to be dewatered and removed.
Thus, there is a continuing need for a separation system that will rapidly and efficiently remove particles and volatile gases from liquids while treating a liquid, will efficiently remove algae and volatile gases such as MTBE during pretreatment prior to filtration and will reduce overall treatment costs and conserves water through less frequent filter cleaning and a smaller sludge volume.

System for separating algae and other contaminants from a water stream


An object of the present invention is to provide a catalyst exhibiting excellent performance particularly in partial oxidation reaction. Another object is to provide a method for efficiently producing carboxylic acid or carboxylic anhydride through vapor-phase partial oxidation of an organic compound by use of an oxygen-containing gas in the presence of the catalyst. The catalyst contains (1) diamond; (2) at least one species selected from among Group 5 transition element oxides, collectively called oxide A; and (3) at least one species selected from among Group 4 transition element oxides, collectively called oxide B. The method for producing a carboxylic acid or a carboxylic anhydride includes subjecting an organic compound to vapor phase partial oxidation by use of an oxygen-containing gas in the presence of the catalyst, wherein the organic compound is an aromatic compound having one or more substituents in a molecule thereof, the substituents each including a carbon atom bonded to an aromatic ring.

1. Field of the Invention
The present invention relates to a catalyst and to a method for producing a carboxylic acid and/or a carboxylic anhydride through vapor-phase partial oxidation of an organic compound in the presence of the catalyst by use of an oxygen-containing gas.
2. Background Art
There has already been known method for producing carboxylic acids through vapor-phase partial oxidation of an organic compound in the presence of a catalyst containing diamond and a Group 5 transition element oxide. Ind. Eng. Chem. Res., 32, 263-273 (1993) discloses a method for growing a porous diamond layer on a metal oxide surface through chemical vapor deposition. The non-patent document describes that the selectivity of the catalytic reaction to form phthalic anhydride through vapor-phase partial oxidation of o-xylene is estimated to be enhanced to a certain extent, based on the simulation results using a specific mathematical model and specific parameters, assuming that a diamond layer can be grown in a vanadium pentoxide (V2O5) surface without impairing its oxidation catalytic activity. The document also discloses that CVD growth of the diamond layer is performed under high-temperature/low-pressure conditions (400 to 500° C. and 25 Torr) in a methane-hydrogen mixture (reducing gas) atmosphere. Meanwhile, under such conditions, vanadium pentoxide is known to be rapidly reduced to low-valence vanadium oxides (see Kogyo Kagaku Zassi, 55, p. 68 (1952), and Nippon Kagaku Zassi 82, p. 276 (1961)), and is known to exhibit insufficient oxidation catalytic activity (see Catalyst, 8, p. 302 (1966)). In other words, in practice, CVD growth disclosed in the aforementioned non-patent document encounters difficulty in producing a vanadium pentoxide catalyst bearing a diamond layer and having a sufficient oxidation catalytic activity. In addition, CVD must be performed by means of a particular processing apparatus with low process efficiency, making CVD a catalyst production method of limited effectiveness. Ind. Eng. Chem. Res., 32, 263-273 (1993) does not address addition of a transition metal element oxide other than vanadium oxide, addition method of a diamond other than CVD, or the morphology of a diamond other than layered structure by CVD growth.
There have already known a large number of methods for producing carboxylic acids through vapor-phase partial oxidation of an organic compound by use of an oxygen-containing gas in the presence of a catalyst containing a Group 5 transition element oxide (particularly vanadium pentoxide), a Group 4 transition element oxide, and a Group 6 transition element oxide. Examples of vapor-phase partial oxidation of a lower hydrocarbon compound or a lower oxygen-containing organic compound include production of acetic acid from butene in the presence of a catalyst such as MoO3—WO3—V2O5 catalyst (see German Patent No. 2,040,455); production of maleic anhydride from a linear C4 compound such as n-butane in the presence of a catalyst such as V2O5—P2O5—TiO2 catalyst (see Japanese Patent 1976-95990A); and production of maleic anhydride from benzene in the presence of a catalyst such as V2O5—WO3—P2O5—TiO2 catalyst (see German Patent No. 1,141,343).
There has already been known vapor-phase partial oxidation of an aromatic compound having a substituent by use of an oxygen-containing gas. Specific examples include production of benzoic acid from toluene in the presence of a catalyst such as V2O5—TiO2—TeO2—Sb2O3 catalyst (see Japanese Patent 1993-255181A); production of phthalic anhydride from o-xylene in the presence of a catalyst such as V2O5—TiO2—Nb2O5—P2O5—K2O catalyst (see Japanese Patent 1974-41036B); production of phthalic anhydride from naphthalene in the presence of a catalyst such as V2O5—Nb2O5—TiO2—P2O5 catalyst (see Japanese Patent 1984-1378B); production of pyromellitic dianhydride from 1,2,4,5-tetraalkylbenzene including durene in the presence of a catalyst such as V2O5—TiO2—MoO3—P2O5 catalyst (see Japanese Patent 1970-15018B), V2O5—TiO2—Ag2O—MoO3—P2O5—CaO catalyst (see Japanese Patent 1995-171393A), or a layered catalyst of V2O5—MoO3—P2O5—Ag2O and V2O5—TiO2-rare earth metal oxide-P2O5—CeO2 (see Japanese Patent 2000-1484A) and production of pyromellitic dianhydride from 2,4,5-trialkylbenzaldehyde in the presence of a catalyst such as V2O5—TiO2—P2O5— (Sb2O5, Cs2O) catalyst (see Japanese Patent 1995-2864A) or V2O5—TiO2—Ag2O—MoO3—P2O5 catalyst (see Japanese Patent 2002-105078A and 2002-105079A).
As described above, the aforementioned patent documents disclose use of a catalyst containing a Group 5 transition element oxide (particularly vanadium pentoxide) with a Group 4 transition element oxide and/or a Group 6 transition element oxide in the production of carboxylic acids through vapor-phase partial oxidation of an organic compound by use of an oxygen-containing gas. However, these patent documents do not mention a similar catalyst containing diamond.
Those catalysts disclosed in the patent documents improve catalytic activity, reaction selectivity, and stability in performance to satisfactory technical levels. However, there is still demand for a more effective catalyst. In particular, in partial oxidation, high reaction selectivity is demanded. In order to improve the selectivity, investigations have generally been performed on additives to the catalyst. Thus, catalysts attaining high selectivity generally contain a large number of components. Such catalysts raise problems in that preparation thereof including blending a number of starting materials and preliminary treatments, is cumbersome, and that the ranges of catalyst composition and reaction conditions for attaining optimum reaction results are limited. In order to solve the problems, it would be advantageous to find catalyst additives which are readily usable and are adaptable to wide ranges of catalyst preparation conditions and reaction conditions.
Meanwhile, vapor-phase partial oxidation of an organic compound by use of an oxygen-containing gas is known to be a vigorously exothermic reaction involving complete combustion. Therefore, there have been widely employed an approach that a catalyst composition containing a Group 5 transition element oxide is caused to be supported on a carrier which is inert to the relevant reaction, to thereby disperse heat. In fact, Japanese Patent 1982-105241A and 1986-28456A disclose self-sintered shaped carriers made of high-purity silicon carbide serving as suitable carriers. However, since such carriers are produced in an inert (non-oxidizing) gas (e.g., nitrogen) atmosphere via a sintering step at very high temperature, the production cost problematically increases. Among silicon carbide carriers, those having a low-purity and containing silica are inexpensive and can be produced in a simple manner through calcinating in air at low temperature. However, such a silicon carbide carrier encounters difficulty in exhibiting good reaction results. Therefore, finding catalyst additives which enable use of inexpensive carriers would be of great industrial value.
Apart from the development of the aforementioned catalyst carriers, development of catalyst itself; i.e., an approach in which a substance which disperse heat is added to a catalyst composition containing a Group 5 transition element oxide has been studied. For example, Japanese Patent 1996-318160A, U.S. Pat. No. 6,660,681, and WO 2000/62926 (pamphlet) disclose such additives; granular silicon carbide; silicon nitride, boron nitride, and aluminum nitride; and granular β-silicon carbide, respectively. However, these patent documents do not disclose a catalyst composition or a catalyst containing diamond.

Catalyst and method for producing carboxylic acid and/or carboxylic anhydride in the presence of the catalyst


For obtaining mineral fibers from a thermoplastic material having a high melting point, and more precisely for the regulation of the flow rate and temperature of the stream of molten material distributed on the fiber-drawing machine, the molten material is conveyed via a reservoir where the flow rate is regulated and the height of the molten material at the base of the tapping aperture is controlled by inclining the reservoir. Preferably the molten material is subject to a basic heating process which raises its temperature close to the fiber-drawing temperature and, in the vicinity of the tapping aperture, it is subject to additional heating in order to adjust the temperature precisely.

1. Field of the Invention
The invention relates to techniques for obtaining mineral fibers produced from a material having a high melting point such an basalt glass, glass based on blast furnace slag or any other similar glass composition. More precisely, the invention relates to the problem of conveying the material in the molten state from its melting chamber to a so-called free centrifuging fiber-drawing machine, i.e. a machine comprising one or more centrifuging wheels rotated at a high speed and onto the periphery of which there is poured the material to be drawn which is entrained by these wheels before some of the material is conveyed to the following wheel and the remainder is transformed into fibers under the effect of centrifugal force. The fibers are immediately entrained to a reception device by means of gaseous currents emitted perpendicular to the direction in which the fibers form.
2. Description of the Related Art
The techniques briefly mentioned above are used in order to produce so called rock wool which is used specially for manufacturing insulating products. They have the great advantage of enabling glasses with a high melting point to be processed, thus leading to products which are highly fireproof and with production and raw material costs which are relatively low, at least in comparison with those used in other fiber-drawing techniques. However, this moderate cost is to a large extent due to a certain simplicity of the technique, in particular as regards the conditioning of the glass.
In effect it is well known that fiber-drawing installations - in particular as regards the fiber yield and the quality of the fibers produced - are assessed more favorably, the more the fiber-drawing machine is supplied with a perfectly conditioned glass. What is understood by "conditioning" conforms to the reference value from the point of view of its composition, its temperature and its flow rate without any large irregularities being noted with respect to these features. Conventional glass-making ovens cannot ensure that this conditioning will be satisfactory since the refractories are rapidly corroded by the glasses used in this type of technique unless they accept temperatures of less than 1450.degree. C. at the furnace outlet while the optimum conditions for drawing fibers are at temperatures in the vicinity of 1600.degree. C. or even slightly more. In fact, in the fiber-drawing techniques examined here, the glass is usually melted in a chamber of the cupola type furnace in accordance with a method similar to that practiced in foundries, except for those differences due to the differing materials. The cupola furnace is a furnace which can produce particularly high flow rates for molten materials with a relatively cost-favorable fuel, e.g., coke, and very low maintenance costs. The cupola furnace is charged at the top alternately with layers of the material to be melted and layers of coke or directly with mixtures of coke and the material to be melted. The combustion of the coke, by means of air or pure oxygen blown into the lower part of the cupola, ensures that the heat required for the glass to melt is released. The molten mixture escapes continuously via a tapping hole located in the vicinity of this lower section. When operation has become established, the effect of a regular supply of alternating charges is in principle the formation of a stack of strata having a fixed thickness and level, the coke combustion and glass melting zone replacing this stack in the area of the nozzles.
Owing to the close proximity of the fusion zone and the nozzles which blow in the oxidizing agent, there is intense turbulence at the tapping hole which is due in particular to the permanent competition between the molten material and the combustion gases which are both attempting to escape. Owing to this fact, the flow is highly spasmodic. On the other hand, a cupola furnace is never as stable as one would wish it to be, and it can happen, for example, that a layer of coke flows violently instead of being gradually consumed with the consequence that blocks of unmelted coke are present in the molten material flow; apart from the great change in the flow rate of the molten material resulting therefrom, this discharge of coke is very harmful to the useful life of the centrifuging wheels which are generally made from refractory steel. In addition, instability of this type in the cupola furnace may lead to variations in temperature and, as a direct result, in the viscosity of the molten material and thus in its behavior during the fiber-drawing process.
In addition to these irregularities in the flow rate and temperature, there are irregularities in the composition of the molten material, if only from the point of view of the content of ferrous and ferric oxides, as the reduction of ferrous oxides to metallic iron is never complete and varies according to the more or less reducing nature of the atmosphere in the cupola furnace atmosphere; on the other hand, even if the melt produced by this reduction of the iron oxides is more dense than the molten glass and accumulates at the base of the cupola furnace, it is not rare to see it escape, although in small proportions it is true, with the flow of molten glass, giving rise to the considerable risk of damage to the centrifuging wheels.
In order to overcome these problems, it is known from French patent FR-B-2 572 390 to position in the path of the molten material a fore-hearth forming a reservoir having a free surface sufficient to at least partially attenuate variations in the flow rate at the outlet of this reservoir. The volume of this reservoir is preferably small and corresponds for example to an operating period of between 30 seconds and 3 minutes.
This small size is desirable in particular in order to restrict the cooling of the molten material held therein and the formation of dead areas, i.e. areas in which the material is in the devitrified state and no longer in the molten state, the fraction of the volume of the reservoir occupied by dead zones of this type being in fact unusable. Nevertheless, it is evident that the smaller the volume of the reservoir, the lesser the homogenization effect of the flow rate and possibly of the glass composition will be, and thus the more difficult it will be to control with any degree of accuracy the key parameters of the fiber-drawing process, i.e., the flow rate, temperature and composition of the molten glass.
In addition, even though the intensity of cooling is restricted, heat losses are no less real, the lowering of the temperature in the reservoir being of the order of 50.degree. to 100.degree. C. for example, which means that the material must be superheated to the same extent in the cupola furnace. Owing to its size and the very principle which controls its operation, the cupola furnace is a type of furnace which does not easily lend itself to extensive regulation of the temperature.
Moreover the fundamental difficulty with a reservoir of this type formed of a free surface with a flow via an overflow is that, by definition, it does not enable the flow rate to be controlled but only the variations thereof to be restricted. The average flow rate is thus imposed by the cupola furnace and cannot be modified with the degree of flexibility and speed desired in order to take account of the actual operating conditions of the fiber-drawing machine and in particular the position and distribution of the molten material stream on the first of the centrifuging wheels.
Patent application WO 90 02711 proposes operating such that material is melted in two stages, a melting stage in the cupola furnace and a superheating phase in the reservoir by means of a plasma heating device. The temperature of the molten material in the cupola furnace is therefore increased by the order of 20.degree. to 150.degree. C. relative to its outlet temperature. A system of this type enables the temperature of the molten glass conveyed over the first centrifuging wheel to be controlled efficiently but at the cost of a relatively complex heating installation which conflicts somewhat with the other, simpler components; the juxtaposition of components having very different technological values preferably being avoided on a production site. Moreover, the technique of heating by plasma can only operate efficiently on small amounts of molten glass, thus with a reservoir having a relatively small volume.
Apart from the disadvantages already cited above in this respect, it should be noted that in practice this also prevents the composition of the molten glass being altered in the reservoir. The possibility of adjustments of this type enables the cupola furnace to be supplied with a standard composition which in always the same while the final composition is adapted to the manufactured product or conversely any undesirable differences in the compositions of the raw materials to be corrected rapidly.
Furthermore, the fact should still be borne in mind that the basic problem of melting in a cupola furnace is that of the irregularity of the flow rates and this problem is only resolved to an unsatisfactory degree in the aforementioned PCT and French publications. In patent application WO-90 02711, the molten glass does not flow via an overflow but via a tapping hole located in the base of the reservoir protected by an immersed barrier which prevents the flow of the melt which, being more dense, is decanted at the base of the reservoir. The flow of molten material depends entirely on the height of the molten glass above the tapping hole, which height depends firstly on the flow rate of the supply to the reservoir and secondly on the dimensions of the reservoir or more exactly on the dimensions of its free surface area. The occupied section of a relatively small reservoir, of a size such that it can be heated using plasma, thus restricts the flow rate regulating capacities.
The same is true when the flow of glass is via a tapping hole at the base of the reservoir, with, moreover, additional difficulties connected with the wear of the tapping nozzles and thus the necessity to replace them, in particular owing to the highly corrosive nature of basalt glasses and the very high temperatures (far above 1000.degree. C.), and also connected with the great tendency of these glasses to devitrify at temperatures scarcely below the temperatures suitable for fiber-drawing, i.e. at which the viscosity of the glass is well adapted to a fiber-drawing process. Even if the nozzle is not cooled, there is a tendency for a crust of devitrified material to form on the nozzle on contact with the colder ambient air, this crust growing to a greater or lesser extent and reducing the passage cross-section of the glass; although this phenomenon may be overcome to a certain extent, it greatly complicates any attempt to regulate the flow rate by permanently altering the opening cross-section of the tapping aperture.
This devitrification phenomenon is particularly critical In the phases when the fiber-drawing machine is started up again since a plug forms which totally blocks the tapping aperture when the cupola furnace in tapped again. This plug must be removed by heating, for example by means of a blowpipe, until the flow is sufficiently great to provide the energy for maintaining the tapping process as a result of the developing crust being permanently leached. This heating stage using a blowpipe involves the risk of damaging the pouring nozzle as a result of overheating.
Furthermore, even in so-called continuous operation, the flow of molten material from the cupola furnace is regularly interrupted, in particular in order to tap off the molten iron accumulated at the base of the cupola furnace, which operation therefore interrupts the production of fibers at a moment which may be inconvenient. It is evident that this stoppage can only be avoided if the volume of the reservoir is relatively large and corresponds for example to a production period of the order of 5 to 10 minutes, the average time required for tapping off the molten iron.

Process and device for obtaining mineral fibers