A method and system of quorum negotiation utilizing power mains. Unlike current systems, this communication is provided as a secondary channel, with the primary channel being a standard network system. By using this technique, if the heartbeat is lost over the primary communication system, the secondary, power-mains system can be used to check the heartbeat to validate whether or not the xe2x80x9clostxe2x80x9d system is still in operation. If communication cannot be established over the power mains, it is assumed that the xe2x80x9clostxe2x80x9d system is down and should be dropped from any cluster.

The present invention relates to clusters of computers, and particularly to data communication between computers in a cluster system.
A xe2x80x9cclusterxe2x80x9d is a collection of computers that work in concert to provide a much more powerful system. (More precisely, a cluster can be defined as a set of loosely coupled, independent computer nodes, which presents a single system image to its clients.) Clusters have the advantage that they can grow much larger than the largest single node, they can tolerate node failures and continue to offer service, and they can be built from inexpensive components. The nodes of the cluster may communicate over network interconnects which are also used to let the cluster communicate with other computers, or the cluster architecture may include a dedicated network which is only used by the nodes of the cluster. As the price of microprocessors has declined, cluster systems based on personal computers have become more attractive. The present application discloses a new cluster architecture.
A key necessity in cluster operations is to coordinate the operation of the members of the cluster. One very fundamental element of this is that each member of a cluster needs to know whether the cluster is still operating, and if so who the other members of the cluster are. This basic need is referred to as xe2x80x9cquorum validation.xe2x80x9d
A current method for quorum validation, i.e. the process of verifying that the cluster members are still present, is to send messages (called xe2x80x9cheartbeatsxe2x80x9d) to other nodes to obtain mutual consent on the agreed upon list of cluster members. These heartbeats include both substantive messages sent by a node, and other messages which simply indicate that the sending node is still connected to the network and functioning correctly. Loss of messaging capability between any nodes (or groups of nodes) in a cluster can be detected by the loss of heartbeats from a given node. When such a loss of messaging occurs, the remaining cluster nodes will attempt to create a new member list of the cluster. This activity is called quorum negotiation.
This capability makes the cluster organization robust. However, this can lead to a particularly acute problem. In some cases loss of messaging can result in multiple partitioned subclusters which all agree on subsets of membership, and which form multiple, partitioned clusters independently operating on, modifying, or creating data intended to be part of a larger data set common to the whole cluster. This is often referred to as the xe2x80x9csplit brain syndrome,xe2x80x9d in that the cluster splits into two disjoint parts that both claim to own some system resource. Eventual rejoining of the independent partitioned clusters into one large cluster will cause the datasets to be re-synchronized, often requiring one or more sets of modified data to be discarded, resulting in a loss of data integrity and a waste of processing cycles. Other details of cluster systems may be found in many publications, including The Design and Architecture of the Microsoft Cluster Service, Proceedings of the FTCS 1998, which is hereby incorporated by reference.
The present application discloses a cluster system and a method of quorum negotiation, utilizing communication over a power mains to provide a secondary communication channel. This secondary channel does not replace the primary channel, which is still a standard or high-speed network system. If the heartbeat is lost over the primary communication system, the secondary channel can be used to check the heartbeat to validate whether or not the xe2x80x9clostxe2x80x9d system is still in operation. If communication cannot be established over the power mains, it is assumed that the xe2x80x9clostxe2x80x9d system is down and should be dropped from any cluster.
In addition, this methodology can be used to reset components or nodes, and to guarantee that the split system is reset. This technique also overcomes the problem of determining whether the entire cluster or just member systems should be reset.

Method and apparatus for cluster system operation

Compaq Information Technologies Group, L.P.


Acetyl esterase producing bacterial strains or functional mutants thereof and methods of using acetyl esterase producing bacterial strains as forage additives are disclosed.

The plant cell wall is a complex structure consisting of different polysaccharides, the major components being cellulose, hemicelluloses and pectins. The resistance of the plant cell wall to digestion presents significant challenges in the animal production industry. Presently, in livestock agriculture while a high-forage diet is desirable, it does not currently satisfy the demands of modern animal production. Fiber digestion is a limiting factor to dairy herd milk yield and composition, and to beef production in beef operations feeding a high forage diet, and hence restricts profitability of farmers. Enhancing fiber digestion has a dual impact: 1) the animal eats more due to a reduced gut fill and therefore produces more, and 2) the animal gets more out of what it eats since the fiber is more digestible. Ultimately, this should increase milk yield, in dairy cows, and beef production in forage fed animals. Farmers either have to put up with a lower level of feed digestibility and hence productivity, or they can use inoculants, forage additives or other amendments that improve the digestibility of feed.
Accordingly, farmers can treat ensiled feed or other animal feed with fiber degrading enzymes, originating mainly from molds, to improve digestibility of feed. In addition, there are several commercially available Saccharomyces cerevisiae yeast strains that when fed to cattle reportedly improve fiber digestion (Erasmus et al., (1992) J. Dairy Sci. 75: 3056-3065; and Wohlt et al., (1998) J. Dairy Sci. 81: 1345-1352). Plant tissues and fibers can be disrupted to help release nutrients by adding organisms or enzymes produced by these organisms to forage before feeding or ensiling.
For example, in U.S. Pat. No. 6,037,161, an Aspergillus acetyl esterase nucleic acid sequence is described which encodes an enzyme with activity towards acetylated xylans that may be used to modify plant materials for enhanced nutrient availability. However, these methods can be difficult and expensive to practice because recombinant technologies, fermentations, and chromatographic processes are required. In addition, the resultant enzyme has a narrow range of substrates and can fail to effectively release nutrients from many plant materials.
Generally, for an animal to make efficient use of the feed it consumes, the energy demands of the microorganisms in the digestive tract must be met and synchronized with the availability of plant proteins. A lack of synchrony will lead to a) proteins and other nutrients being poorly utilized in the digestive tract, b) a loss of nitrogen, in urine and feces and c) a need to feed excessive amounts of protein concentrates as supplements to the diet. The use of organisms and enzymes can improve or enhance the value of the feed animals receive and the performance of the animals. For example, WO 92/10945 discloses such a combination for use in enhancing the value of prepared silage. WO 93/13786 and WO 96/17525 relate to the enhancement of animal performance using microorganisms, while WO 93/13786 refers to a species of Lactobacillus.
Silage can be spoiled when aerobic organisms, such as some yeast and molds, propagate in the stored feed. For example, silage can be damaged by air leaks in a silo or when air is introduced while farmers are removing part of the silage. In the presence of oxygen, yeasts, molds, and aerobic bacteria can consume nutrients, and release unpleasant or toxic metabolites. This elevated aerobic microbe activity has been considered undesirable since it often results in aerobic spoilage of silage and the consequent depletion of silage dry matter (DM) nutrition. However, some microbes, such as killer yeast (see U.S. Pat. No. 6,489,158) and Lactobacillus buchneri strains (see U.S. Pat. No. 6,326,037) can beneficially inhibit growth of spoilage microbes thereby stabilizing nutrient value of ensiled plant materials. A further method to reduce this problem is to inoculate the silage with a fast growing microbe, such as Lactobacillus species, which release organic acids to lower the silage pH and inhibit growth of spoilage organisms.

Acetyl esterase producing strains and methods of using same


The invention provides a printer in which a lock lever comes into contact with a roller shaft of a platen roller in upper open grooves disposed in a frame and controls the position of the upper portion of the upper open grooves so that the platen roller is supported in a predetermined position of the frame and reliably comes into contact with a thermal head disposed to be opposite to the platen roller, and a lock lever member disposed so as to position a joint member for joining the upper open grooves and close to a bottom plate of the frame in a print portion in which the platen roller and a thermal head come into pressure contact with each other.

1. Field of the Invention
The present invention relates to a printer, and particularly to the printer including a device in which a print head supports a platen which is detachable so that the print head can come into pressure contact with the platen.
2. Description of the Related Art
The known printer in which a platen roller is detachable, print paper can be easily loaded, and the like has been used.
For example, in the printer disclosed in JP-A-2000-318260, the platen roller has a roller shaft and is retained in U-shaped grooves (hereinafter, referred to as upper open grooves) which is formed in a pair of lateral plates formed in the right and left of a frame and of which the upper portion is open. In addition, the roller shaft is controlled in the right, left, and lower directions in position by the upper open grooves and controlled in the upper direction in position by a lock lever disposed in both the lateral plates of the frame.
The lock levers are lever members disposed to be rotatable around the rotation point of the frame and are together joined by the joint member with a plate shape to constitute the lock lever member. The lock lever member is disposed in the frame so as to allow the joint member to be positioned in the opposite side of the platen roller of a thermal head, which is the print head disposed to come into contact with the platen roller. In addition, a spring member urging the thermal head retention plate and the joint member to move away is mounted between thermal head retention plates which bear the joint member and the thermal head.
The spring member applies an urging force for locking a roller shaft of the platen roller between the lock lever and the upper open groove of the frame. In addition, the spring member also applies the urging force for bringing the thermal head into pressure contact with the platen roller in a state where the roller shaft of the platen roller is locked between the upper open groove of the frame and the lock lever.
As described above, the lock lever member is disposed in the frame so that the joint member is positioned in the opposite side of the platen roller of the thermal head. Such a configuration does not meet the recent requirement of a decrease in size.
In addition, one spring member allows the lock lever to lock the roller shaft and urges the thermal head to come into pressure contact with the platen roller. Consequently, the one spring member cannot adjust only the spring load required to lock the lock lever and in the roller shaft for itself, for example.

Printer with a print head urged to come into contact with a platen roller


A method and an apparatus for making a conductive circuit in sheet form. A circuit trace is firstly designed using a CAD (computer aided design) system and a computer aided cutting device is operated by the CAD to cut the desired circuit trace in a thin foil sheet which is adhesively secured to a release backing sheet. The non-circuit trace portions of the foil sheet are removed from the adhesive release backing sheet leaving only the circuit trace. An adhesive transfer sheet is then used to remove the actual circuit trace, in an undisturbed manner, from the release sheet and applied it to a support base. Because the circuit trace has an adhesive backing, it will adhere to the support base. A multi-layer flexible electric conductive circuit can also be fabricated with this method and the transfer sheet can also be utilized as an insulating layer.

1. Field of the Invention
The present invention relates to an electrically conductive thin metal foil circuit trace having an adhesive backing for securement to a base. The circuit trace is firstly supported on a release sheet and is transferred therefrom and onto the base by the use of an adhesive transfer sheet.
2. Description of Prior Art
Various types of printed circuits are known. For example, U.S. Pat. No. 4,799,984 describes a method of fabricating a multi-layer circuit on a rigid ceramic substrate. However, all of these methods utilize a printing process for forming the printed circuit and firing process to form thick film conductors and insulating dielectrics on rigid insulated substrate material, such as alumina. The printing is usually effected through a screen mesh. In the above-referred to U.S. Patent, there is described an improved method of fabricating multi-layer circuits but this method still utilizes a firing step and uses solid substrates. Reference is also made to U.S. Pat. No. 4,891,242 which teaches the use of an automatic apparatus in which an ink jet head is displaced on an X-Y axis of a computer-aided machine (CAD) to form a circuit pattern instead of using the usual screen mask of the prior art. This eliminates the use of many screen masks to form a printed circuit and also saves time in designing and manufacturing as compared to the screen mask techniques. Again, with this method, it is necessary to bake a solution into the substrate.

Electrically conductive circuit sheet and method and apparatus for making same


An apparatus for controlling operation of a processor device during startup of the processor device includes: (a) a signal treating circuit receiving a voltage supply signal at a voltage supply locus; the signal treating circuit using the voltage supply signal for generating a first treated signal and a second treated signal; and (b) an output circuit coupled with the signal treating circuit; the output circuit receiving the first treated signal and the second treated signal and generating a control signal at an output locus based upon a relationship between the first treated signal and the second treated signal; the output locus being coupled with the processor device; the control signal effecting the controlling.

The present invention is directed to controlling operation of a processor device during startup of the processor device, and especially to reset supervisor apparatuses that await a stable supply signal in effecting such processor device control.
Often in operation of processor devices, and especially in processor devices in embedded systems, the power-up of the supply voltage is not a clean event. That is, the supply voltage is not sufficiently stable immediately after power-up to reliably operate a processor device. Such initial instability of supply voltage is especially present in battery operated systems because the insertion of a battery often causes significant ringing, "glitching" or other disadvantageous anomalies in the supply signal. An example of such noise on a supply line is illustrated in FIG. 1.
By way of further example, and not by way of limitation, in products with on-off switches contact bounce of the switch can also cause unclean power-up of the supply signal. If the power-up evolution involves too much noise or other signal anomalies a processor may experience a brownout condition. A brownout condition is generally considered to be an errant condition of the processor that requires a reset operation to be performed before the processor behaves as expected. The processor is sometimes said to be "lost" or "off in the weeds" during a brownout condition.
Some type of reset supervisor apparatus may be employed to control the reset pin of the processor to avoid a brownout condition. One such reset supervisor apparatus is a supply voltage supervisor (SVS) circuit that can hold the processor in a reset condition (i.e., reset the processor) until the supply voltage reaches a predetermined voltage. Such SVS circuits also reset the processor after the processor begins operation if the supply voltage dips below the predetermined voltage. A problem with prior art SVS circuits has been that the threshold level at which an SVS circuit operates often does not fit well with the system with which it is employed. For example, the predetermined threshold voltage may be lower than the minimum operating voltage of the processor monitored by the SVS circuit, or the predetermined threshold voltage may be higher than the desired operating voltage of the predetermined voltage or of the system within which the processor is included.
There is a need for an apparatus and method for controlling operation of a processor during startup that is independent of the level of the supply voltage provided to a processor device.
There is a need for an apparatus and method for controlling operation of a processor during startup that provides a reset to the processor based on stabilization of the supply voltage and not based on a predetermined threshold value.

Apparatus and method for controlling operation of a processor device during startup


Embodiments of the invention provide a method and system for solving a prediction problem. The computer-implemented method comprises: decomposing a target sequence associated with the prediction problem into a binary sequence group including at least one binary sequence, wherein each binary sequence in the group is generated based on a corresponding multiplier value; generating a plurality of elementary sequences based on each composite sequence in the binary sequence group; determining initial weights of each composite sequence based on average of weights of the corresponding elementary sequences; determining a binary prediction value for each binary sequence, wherein the binary prediction value for each composite sequence is determined by modelling each composite sequence using RNN based on the determined initial weights; and determining a real prediction value for the target sequence based on a product of the binary prediction value for each binary sequence and the corresponding multiplier value.

Sequence prediction has many applications, e.g. machine failure prediction, network congestion prediction, prediction of ink level of a printer, and prediction of bandwidth utilization of a communication line etc. Basically, a prediction problem is to estimate a future value of a quantity of interest based on a sequence of past values of the quantity over a time period. Success of a prediction process is judged by how well the predicted values match with the actual values of the quantity of interest.
The prediction process can be considered as an optimization process, which tries to adjust its parameters of a functional relationship in such a way that it generates the sequence by capturing the internal representation of the process, which might have generated the actual values. The difficulty in modelling these kinds of sequences is to find the parameter values of the model in a consistent way, which does not consume too much time. The challenge is to find a generic and robust mechanism, which works for all sequences, small or large and having small or large temporal dependencies and can be computed quickly.
Recurrent neural networks (RNNs) have been widely used for sequence prediction as RNNs which have recurrent connections are naturally suitable for sequence learning. However, standard RNNs can't handle large temporal dependencies, typically not more than 15 time steps, because of vanishing and exploding gradient problems. Although several algorithms including LSTM and GRU have been proposed to try to avoid the vanishing and exploding gradient problems, these algorithms are complex and a specialized structure of network is required. Further, none of the existing algorithms can ensure that a sequence can be modelled always within a reasonable time period, especially in the presence of a long temporal relationship.

Method and system for solving a prediction problem


A screwdriver helper includes a handle, a guide, and a bit. The handle defines a through hole therein. The guide is affixed to the handle. The guide comprises a top surface, a bottom surface, and a through guide hole defined between the top surface and the bottom surface. The top surface is faced to the handle. The guide hole is corresponding to the through hole of the handle. An axis of the guide hole is perpendicular to the bottom surface. The bit is positioned in the guide hole. The bit comprises a tip and a head. The tip is in a shape of a screw head. The head defines slots in a top end thereof. The bit is movable along the axis of the through guide hole. The screwdriver helper helps screwdriver to lock screws firmly.

1. Technical Field
The present invention relates to a screwdriver helper.
2. General Background
Screwdrivers are usually used to insert or remove screws. However, in some cases, the screws cannot be firmly tightened after insertion. For example, referring to FIG. 5, a notebook computer's main body 10 is disclosed. The main body 10 includes a battery case 11. Some holes, such as hole 12, are defined in the walls of the battery case 11, for receiving screws. Referring to FIG. 6, a screwdriver 20 is used to drive a screw 30 into the hole 12. Because of the size of the screwdriver chuck the screwdriver 20 must be tilted to drive the screw 30, thus the threads of the screw 30 or the threads of the hole 12 may strip because the driving force is not along the axis of the hole 12.
Thus, what is needed is a device that is able to insert or remove screws located in awkward positions.

Hong Fu Jin Precision Industry (ShenZhen) Co., Ltd.


Methods and apparatus for performing frequency domain analysis using compressed matrix storage to reduce the computation and storage requirements associated with processing a system of harmonic balance equations. A nonlinear circuit, system or other device to be analyzed includes n unknown node spectra, each characterized by N spectral coefficients in the system of harmonic balance equations. A compressed version of a Jacobian matrix J representing the system of harmonic balance equations is generated by forming m sequences of length N using one or more block-diagonal matrices associated with the Jacobian matrix J, converting each of the m sequences to the frequency domain using a discrete Fourier transform, such that a set of Fourier coefficients are generated for each of the m sequences, and storing only those Fourier coefficients which exceed a threshold as the compressed version of the Jacobian matrix J. Information generated from an inverse transform of the compressed version is utilized to solve a preconditioned linear system J.sup.-1 JZ=J.sup.-1 W which is based on an approximation J of the Jacobian matrix J.

A technique known as "harmonic balance" is commonly used to provide fast and accurate steady-state analysis of nonlinear circuits. The harmonic balance technique is particularly well-suited for analysis of nonlinear circuits driven by two or more periodic inputs at widely separated frequencies. Unlike other conventional analysis techniques, the computation time required for a harmonic balance analysis is substantially insensitive to the actual numeric values of the stimuli frequencies. The harmonic balance technique generally involves expressing each of n circuit node waveforms as a Fourier series truncated to N coefficients, then replacing the differential equations describing the circuit operation with a system of nonlinear algebraic equations involving the Fourier coefficients. This replacement is possible because the derivative with respect to time of a Fourier series is an algebraic operation. A numerical technique, such as Newton's method, is then employed to solve the resulting system of nonlinear equations. Additional details regarding the harmonic balance technique may be found in, for example, K. S. Kundert, J. K. White and A. Sangiovanni-Vincentelli, "Steady-State Methods for Simulating Analog and Microwave Circuits," Kluwer, Boston, Mass., 1990; R. J. Gilmore and M. B. Steer, "Nonlinear Circuit Analysis Using the Method of Harmonic Balance--A Review of the Art. Part I. Introductory Concepts," Int. J. on Microwave and Millimeter Wave Computer Aided Engineering, Vol. 1, No. 1, 1991; and V. Rizzoli, C. Cecchetti, A. Lipparini and F. Fastri, "General-Purpose Harmonic Balance Analysis of Nonlinear Microwave Circuits Under Multitone Excitation," IEEE Trans. Microwave Theory and Tech., Vol. MTT-36, pp. 1650-1660, December 1988, all of which are incorporated by reference herein.
As noted above, n is used to denote the number of node waveforms which must be stored to capture the behavior of the circuit being analyzed. Even a medium-sized integrated circuit (IC) can have hundreds of nodes, especially if a sophisticated transistor model is used. The transform dimension N can also become large in the case of a multi-tone analysis. For the simulation of a mixer, for example, a designer might request 16 harmonics of the mixer local oscillator and 8 harmonics of the input signal frequency. Because two real numbers are needed to capture the amplitude and phase of each spectral component, the final transform dimension is on the order of N=2.times.8.times.16=256. The overall dimension of the system of harmonic balance equations is nN, which can become quite large in practical applications. Letting X denote the aggregate vector of all unknown Fourier coefficients, the harmonic balance equations may be written as a harmonic balance system H(X)=0 of size nN.
The preferred conventional methods for solving harmonic balance equations are Newton-based techniques due to their fast convergence and high accuracy. Such techniques are described in, for example, J. M. Ortega and W. C. Rheinboldt, "Iterative Solutions of Non-linear Equations in Several Variables," Academic Press, New York, 1969, which is incorporated by reference herein. However, most implementations of Newton-based techniques require the use of a Jacobian matrix .differential.H/.differential.X which is of dimension nN and is generally much more dense than conventional matrices which arise in numerical circuit simulation. As a result, inversion of the harmonic balance Jacobian matrix becomes a computational bottleneck and is largely responsible for the limitation of conventional harmonic balance techniques to analysis of relatively small circuits. Other techniques have been proposed which attempt to simplify or avoid the inversion of the Jacobian matrix. For example, V. Rizzoli, F. Mastri, F. Sgallari and V. Frontini, "The Exploitation of Sparse Matrix Techniques in Conjunction with the Piece-Wise Harmonic Balance Method for Nonlinear Microwave Circuit Analysis," IEEE MTT-S Int. Microwave Symp. Digest, Dallas, pp. 1295-1298, May 1990, which is incorporated by reference herein, attempts to solve the harmonic balance equations using approximate inversions of the Jacobian matrix. A technique described in S. A. Maas, "Nonlinear Microwave Circuits," Artech House, 1988, which is incorporated by reference herein, attempts to solve the harmonic balance equations without using the Jacobian matrix at all.
However, there are a number of advantages associated with exact inversion of the full harmonic balance Jacobian matrix. First, Newton's method with accurate Jacobian matrix inversion exhibits local quadratic convergence, that is, a solution to the harmonic balance system can be obtained to machine precision in a fixed, small number of iterations. Thus, the overall solution time would be small if the accurate Jacobian inversion could be done efficiently. Second, widely convergent continuation methods for solving the harmonic balance equations generally also require solving linear systems involving the Jacobian matrix as a sub-matrix. These widely convergent continuation methods are described in greater detail in, for example, L. Watson, "Globally Convergent Homotopy Methods: A Tutorial," Appl. Math. and Comp., Vol. 31BK, pp. 369-396, 1989, which is incorporated by reference herein. Finally, the inverted Jacobian matrix can be interpreted as a linearization of a circuit in a small-signal sense, and can therefore be utilized for sensitivity computation and noise analysis, as described in S. W. Director and R. A. Rohrer, "Automated Network Design--the Frequency Domain Case," IEEE Trans. Circuit Theory, Vol. CT-16, pp. 330-337, 1969, and R. A. Rohrer, L. Nagel, R. Meyer and L. Weber, "Computationally-Efficient Electronic Circuit Noise Calculations," IEEE J. Solid State Circuits, Vol. SC-6, pp. 204-213, 1971, respectively, both of which are incorporated by reference herein. Additional support for the need for accurate Jacobian inversion may be found in V. Rizzoli, F. Mastri and D. Masotti, "A Hierarchical Harmonic Balance Technique for the Efficient Simulation of Large Size Microwave Circuits," 25.sup.th European Microwave Conference, Bologna, Italy, September 1995, pp. 615-619, which is incorporated by reference herein. Fast and accurate inversion of the Jacobian matrix is therefore a key enabling technology for further progress in the analysis of large nonlinear circuits as well as in other important applications of the harmonic balance technique.
It is apparent from the above that a need exists for improved techniques for inverting or otherwise processing a harmonic balance matrix generated as part of a frequency domain analysis of a large nonlinear circuit or other device, such that the storage and computation requirements associated with processing the matrix are considerably reduced.

Efficient frequency domain analysis of large nonlinear analog circuits using compressed matrix storage


This is to provide an aqueous metal surface treatment agent for a lithium ion secondary battery which can improve interlaminar adhesiveness between a metal member and a resin coating layer such as a film or a coated film, and solvent resistance without using trivalent chromium.

A treatment agent for treating the surface of a metal has been used in broad fields such as automobiles, home electric appliances, architecture, foods, medicines, etc., in particular, it is useful for improving interlaminar adhesiveness between a metal material such as aluminum, magnesium, copper, iron, zinc, nickel or an alloy thereof, and various resin coating layers provided on the surface thereof, solvent resistance of the resin coating layer and corrosion resistance of the metal material.
Examples of the metal surface treatment agent of the prior art include an aqueous treating solution using trivalent chromium (Patent Literature 1). This treating agent can be used without using hexavalent chromium having high toxicity, but when it is exposed to high temperature environment, oxidation of chromium proceeds to generate hexavalent chromium. Thus, there are problems of environment.
In view of such a background, non-chromium treating agents have been investigated variously until now. In particular, in the uses which require corrosion resistance, adhesiveness with a paint, a resin or the like, there are problems that the performances are insufficient. Therefore, trivalent chromium treating agents which are harmful to human body or environment have yet been used.
Among these, a package for a lithium secondary battery, a film-attached tab lead member and the like are required to have severe adhesion reliability such as electrolyte resistance, HF resistance and the like, in the adhesion of a polyolefin film such as polyethylene and polypropylene with a metal such as aluminum, copper and nickel, and various non-chromium type techniques have been published (Patent Literature 2). However, it is the present status that the non-chromium type treating agents are inferior in surface treatment performances to those of the conventional trivalent chromium type treating agent.

Aqueous metal surface treatment agent for lithium ion secondary battery

Abstract: The aqueous metal surface treatment agent for a lithium ion secondary battery comprises a polyvinyl alcohol resin containing 2 to 15 mol % of a 1,2-diol structural unit represented by the formula (1):

Abstract: Having a degree of saponification of 90 to 99.9 mol % and an average degree of polymerization of 250 to 3000; and a metallic crosslinking agent.

THE NIPPON SYNTHETIC CHEMICAL INDUSTRY CO., LTD.


An optical waveguide device comprises an optical waveguide for guiding an optical wave therethrough, and a grating coupler located on a surface of the optical waveguide in order to radiate the guided optical wave, which travels in the optical waveguide, out of the optical waveguide. The grating coupler is provided with a plurality of bars, the heights h of which increase approximately linearly and little by little in the direction along which the guided optical wave travels. The inclination b of the variation of the bar heights h satisfies the condition ##EQU1## where a represents a coefficient which determines a radiation loss coefficient .alpha. (.alpha.=ah.sup.m, where 2<m), and L represents the length of the grating coupler, which length is taken in the direction along which the guided optical wave travels. The guided optical wave is radiated very efficiently as an approximately Gaussian beam out of the optical waveguide, or an external optical wave, which takes on the form of a Gaussian beam, is introduced very efficiently into the optical waveguide.

1. Field of the Invention
This invention relates to an optical waveguide device. This invention particularly relates to an optical waveguide device, which has an optical waveguide for guiding an optical wave therethrough and a grating coupler disposed on the surface of the optical waveguide such that the guided optical wave may be radiated by the grating coupler out of the optical waveguide, or such that an external optical wave may be introduced by the grating coupler into the optical waveguide.
2. Description of the Prior Art
Recently, a light deflector utilizing an optical waveguide has been proposed in, for example, Japanese Unexamined Patent Publication No. 62(1987)-77761 which corresponds to U.S. Pat. No. 4,778,991. The proposed light deflector comprises a slab-shaped optical waveguide, which is constituted of a material capable of propagating a surface acoustic wave therethrough, and a means for generating a surface acoustic wave in the optical waveguide such that the surface acoustic wave may travel in a direction that intersects an optical path of an optical wave guided by the optical waveguide. The frequency of the surface acoustic wave is changed continuously. By way of example, the means for generating a surface acoustic wave is constituted of an interdigital transducer and a driver for applying an alternating voltage, the frequency of which changes continuously, to the interdigital transducer.
With the aforesaid light deflector, the optical wave guided by the optical waveguide undergoes Bragg diffraction due to an acousto-optic interaction with the surface acoustic wave. The angle of diffraction changes in accordance with the frequency of the surface acoustic wave. Therefore, by varying the frequency of the surface acoustic wave in the manner described above, the optical wave can be deflected continuously in the optical waveguide.
Also, a novel light modulator has been proposed in, for example, Japanese Unexamined Patent Publication No. 1(1989)-178918 which corresponds to U.S. Pat. No. 4,961,632. With the proposed light modulator, the intensity of a surface acoustic wave, which travels through an optical waveguide, is modulated (or the surface acoustic wave is turned on and off), and Bragg diffraction of an optical wave guided by the optical waveguide is thereby controlled.
The optical wave, which has been deflected or modulated in the manner described above, can be radiated out of the optical waveguide by a grating coupler, a prism coupler, or the like, which is formed on the surface of the optical waveguide.
A recording medium may be scanned with an optical wave, which has been radiated out of the optical waveguide device constituted in the manner described above, and an image may thereby be recorded on the recording medium. In such cases, in order for a highly accurate image to be recorded, it is necessary that the scanning optical wave be converged into a small beam spot and the beam spot has a Gaussian intensity distribution at least with respect to a sub-scanning direction.
Also, in order for an optical wave utilization efficiency to be kept high, it is necessary that a guided optical wave be radiated out of an optical waveguide as efficiently as possible (e.g. at an efficiency of approximately 100%).
However, in cases where a guided optical wave is radiated out of an optical waveguide by using a grating coupler, it is very difficult for a beam spot having a Gaussian intensity distribution to be obtained. FIG. 5 is an explanatory view showing how the intensity of an optical wave, which has been radiated out of a grating coupler of a conventional optical waveguide device, is distributed. In FIG. 5, a linear grating coupler 42, which has uniform bar height and pitch, is located on the surface of an optical waveguide 41 formed on a substrate 40, and a guided optical wave 43 is radiated out of the optical waveguide 41. In such cases, as indicated by curve g, the intensity of a radiated optical wave 43' decreases exponentially with respect to the direction along which the guided optical wave 43 travels.
The exponential decrease in the intensity of the radiated optical wave 43' will hereinbelow be described in more detail. It is known that loss of the amount of the guided optical wave 43, .DELTA.I, (output optical amount) for a small region .DELTA.x of the grating coupler is expressed as ##EQU2## where I(x) represents the amount of the guided optical wave 43, and .alpha. represents the radiation loss coefficient. The radiation loss coefficient .alpha. is expressed as EQU .alpha.=ah.sup.m ( 2)
where h represents the heights of bars (or the depths of grooves) of the grating coupler, and a represents a coefficient. Solving the differential equation of Formula (1) under the boundary conditions of I(x)=Io for x=0 yields EQU I(x)=I.sub.o e.sup.-2.alpha.x ( 3)
From Formula (3), the entire amount of the radiated optical wave per unit length is expressed as ##EQU3##
In general, in the cases of rectangular gratings, the optical wave, which has been radiated out of a rectangular grating, is not constituted of a single wave, but multiple beam coupling is effected. Also, in the cases of weak coupling (i.e. when the radiation loss coefficient .alpha. is small), the ratio, P, of a radiated optical wave, which is to be utilized, to the entire radiated optical wave is constant. The intensity, J(x), of the optical wave to be utilized, which is radiated from a certain position x, is expressed as ##EQU4## Substitution of J(x) into Formula (4) yields EQU J(x)=2.alpha.PI.sub.o e.sup.-2.alpha.x ( 5)
For a grating coupler having uniform bar height, the value of h is constant, and substitution of Formula (2) into Formula (5) yields EQU J(x)=2P.multidot.(ah.sup.m)e.sup.-2ah.spsp.m.sbsp.x
Therefore, it can be known that the optical wave, which has been radiated out of a grating coupler having uniform bar height, has an exponentially decreasing intensity distribution.
In cases where a guided optical wave is to travel in the optical waveguide as shown in FIG. 5 and is deflected with a surface acoustic wave, the direction of the deflection (i.e. the main scanning direction) intersects the plane of the sheet of FIG. 5, and the sub-scanning direction is indicated by the arrow v. Specifically, the radiated optical wave 43' has an intensity distribution such that the intensity may decrease or increase exponentially with respect to the sub-scanning direction. Therefore, it is very difficult for a beam spot to be obtained which has a Gaussian intensity distribution with respect to the sub-scanning direction.
The aforesaid problem occurs when a guided optical wave is radiated by a grating coupler out of an optical waveguide. In cases where an external optical wave is introduced into the optical waveguide by using the grating coupler, the problem occurs in that the incident coupling efficiency cannot be kept high. Specifically, as can be understood from the reciprocity theorem regarding radiation and incidence of an optical wave, unless the incident optical wave has the intensity distribution indicated by curve g in FIG. 5, an optical wave cannot be introduced into the optical waveguide at a high efficiency as a whole. However, in general, optical waves produced by light sources, such as laser beam sources, have Gaussian intensity distributions with respect to the directions of diameters of optical wave beams. It is very difficult for such optical waves to be shaped into beams having an intensity distribution such that the intensity decreases or increases exponentially.
A novel grating coupler for solving the aforesaid problems has been proposed in Japanese Unexamined Patent Publication No. 61(1986)-286807. The proposed grating coupler is provided with bars having depths which are increased gradually in the direction along which a guided optical wave travels. However, this publication does not indicate anything about how the rate of change of the bar depths should be set for obtaining an approximately Gaussian radiated beam from the grating coupler and radiating a guided optical wave out of the grating coupler at a high efficiency (e.g. approximately 100%).
A different novel grating coupler for solving the aforesaid problems has been proposed in Japanese Unexamined Patent Publication No. 1(1989)-107213. The proposed grating coupler is provided with bars having heights which vary in a mountain pattern in the direction along which a guided optical wave travels. This publication indicates in detail how the heights of the bars of the grating coupler should be varied for obtaining an approximately Gaussian radiated beam from the grating coupler. However, the grating coupler provided with the bars having heights which vary in a mountain pattern is very difficult to fabricate.
Also, Japanese Unexamined Patent Publication No. 1(1989)-107213 does not indicate anything about how the heights of the bars of the grating coupler should be varied for radiating a guided optical wave out of the grating coupler at a high efficiency.
In Japanese Unexamined Patent Publication No. 4(1992)-40404, an optical waveguide device is disclosed wherein the heights of bars of a grating coupler are defined strictly such that the problems described above can be solved. Though the problems described above can be solved with the disclosed optical waveguide device, it has the drawbacks in that it is effective only when m=2 in Formula (2). It has heretofore been considered that the radiation loss coefficient .alpha. will be expressed as .alpha.=ah.sup.2. However, according to research carried out recently, it was confirmed that the radiation loss coefficient .alpha. may often be expressed as .alpha.=ah.sup.m, wherein 2<m, depending upon the structure of the optical waveguide, or the like.


An apparatus and method for forming a cup (10) having a profiled bottom generally includes a draw die (20) disposed at a first level of a double acting press. The draw die (20) cooperates with a draw pad (22) and a cut edge (24) to form and hold a blank (28) formed from a sheet of material (M). A punch assembly (30) is configured to travel through the draw die (20), thereby drawing the blank (28) over the draw die (20) into a cup (60). The punch assembly (30) transports the cup (60) to a second level of the press where it bottoms out on a die core (50) and a ring pad (51). One element of the punch assembly (30) continues to move beyond the second level of the press, thereby drawing a portion of the cup (60) over the die core (50) and profiling the bottom of the cup (60). The profiled cup (10) is then returned to the second level of the press where it is removed from the punch assembly (30) and transferred. The bottom profile insures that the cup will retain its shape during the transfer operation.

One of the initial steps in forming cylindrical containers such as cans for carbonated beverages is forming a cup. A typical cup includes a circular base connected to a cylindrical sidewall. The cup is typically shorter and wider than a finished container. As such, the cups are typically subjected to a variety of additional processes that further form the cup into a finished container.
Container manufacturing lines operate at high speeds to produce large quantities of containers. Throughout these manufacturing lines, the container elements are transported from one work station to another work station where different forming processes are performed. One of the problems encountered in designing the manufacturing lines is that the container elements often become deformed when being transported from station to station. As the speed of the lines increases, the number of container elements that become deformed increases. This problem is aggravated by the constantly increasing economic pressures to reduce the gauge of the material used to form the containers. The deformations are caused by the collisions between the container elements and contact between the container elements and the machinery.
One deformation problem occurs after the initial step of forming a cup from a flat blank of material has occurred. The cups are generally intended to have circular bottoms with straight, cylindrical sidewalls. Later processes that further form these cups include tooling designed to operate on substantially cylindrical cups. After the cups are initially formed, however, various forces can cause the cups to warp. If a cup is sufficiently warped, the container eventually formed from it must be discarded as waste. Additionally, tooling damage and/or jamming can occur. It has therefore become desirable to form a cup that is more resistant to warping and deformation.

Method and apparatus for forming a bottom-profiled cup


A voltage is sensed at a switching device and the voltage is associated with a status of a switching device. The sensed voltage is converted to a useable voltage regardless of the value and type of the sensed voltage. At a single self-contained integrated circuit that is powered by the sensed voltage, the usable voltage is converted into a digital representation. The digital representation is configured to be usable by a processing device to determine the value of the voltage at the switching device.

Field of the Invention
The subject matter disclosed herein relates to sensing information associated with switching devices and, more specifically, to sensing this information according to a wide range of operating conditions.
Brief Description of the Related Art
Different types of switching devices (e.g., electrical contacts, switches, and so forth) are used in various environments. For example, a power generation plant uses a large number of electrical contacts (e.g., switches and relays). The electrical contacts in a power generation plant can be used to control a wide variety of equipment such as motors, pumps, solenoids and lights. A control system needs to monitor the electrical contacts within the power plant to determine their status in order to ensure that certain functions associated with the process are being performed. In particular, the control system determines whether the electrical contacts are on or off, or whether there is a fault near the contacts such as open field wires or shorted field wires or grounded field wires that affect the ability of the contacts to perform their intended function.
One approach that a control system uses to monitor the status of the electrical contacts is to send an electrical voltage (e.g., a direct current voltage (DC) or an alternating current (AC) voltage) to the contacts in the field and determine whether this voltage can be detected. The voltage, which is provided to the electrical contacts for detection, is known as a wetting voltage. If the wetting voltage levels are high, galvanic isolation in the circuits is used as a safety measure while detecting the existence of voltage. Detecting the voltage is an indication that the electrical contact is on or off. A wetting current is associated with the wetting voltage.
Various problems have existed with previous devices. For example, the contacts need to be isolated from the control system due to the application of high wetting voltage, or damage to the control system may occur. Also, the control system may need to handle a wide variety of different voltages, but previous devices only handle voltages within a narrow range. Previous devices have also been inflexible in the sense that they cannot be easily changed or modified over time to account for changes in the operating environment. All of these problems have resulted in general dissatisfaction with previous approaches.

Loop powered isolated contact input circuit and method for operating the same


A lithium ion secondary cell comprises a plurality of single cells composed of a collector comprising positive electrodes composed of a metallic material coated with a positive electrode active substance; negative electrodes composed of a metallic material coated with a negative electrode active substance; separators interposed between the positive and negative electrodes; lugs of the metallic materials where the active substance is not coated; and conductors adapted to bunch and clamp the lugs of the positive and negative electrodes separately, the positive and negative electrodes being assembled in laminate alternatively, and the ends of the lugs of the positive and negative electrodes being welded to the respective conductors separately so that electric current can be taken out through the conductors.

The present invention relates to a lithium ion secondary cell, and more particularly, to a lithium ion secondary cell having a large capacity and high energy density and capable of application in fields where there is high demand for maintenance-free properties of the products or system, such as in the manufacture of electric automobiles, load leveling of electric power, etc.
To meet the need for miniaturization and light-weight of electronic devices in recent years, there have been developed as a power source, lightweight, miniaturized lithium ion secondary cells and these have been practically used in certain electronic devices such as handheld video cameras, portable personal computers and the like. However, the maximum capacity of these lithium ion secondary cells in practical use is around 5-20 Wh and these are mostly cylindrical in shape.
On the other hand, because of the increasing demand for protecting the environment and saving resources, there has been increasing interest shown in electric automobiles, and also in the need to use load leveling of electric power for effective utilization of nighttime power supply. These demands require the development of large-capacity and low-cost maintenance-free secondary cells.
The lead accumulators widely used in these fields at present are low in output of energy and also inconvenient for use because of heavy weight. Also, these lead accumulators involve the problems relating to maintenance such as the necessity of water replenishment, and their charge-discharge cycle life is as short as about 600 cycles, resulting in a high cost for these batteries. Nickel-cadmium batteries are also used, but their use is limited as the nickel-cadmium batteries are low in energy density, and high in manufacturing cost compared with lead accumulators.
Other types of batteries such as nickel-zinc batteries and sodium-sulfur batteries have been experimentally used for electric automobiles, but they involve their own problems such as short charge-discharge cycle life (nickel-zinc battery) and high possibility of causing dangerous conditions (sodium-sulfur battery).
A Lithium ion secondary cell is suited for these applications because of its high energy density and its structural features of being a closed type and maintenance-free, but none with a large capacity has ever been commercially produced. For application to these uses for electric automobiles, the battery is required to have a capacity on the order of 1,000-5,000 Wh, which is more than 100 times the capacity now available.
The lithium ion secondary cells in practical use are mostly of the cylindrical type, but those with a large capacity of the order of 1,000 to 5,000 Wh required for electric automobiles, load leveling, etc., must be square-type cells comprising an assembled cell of two or more of series-connected 3-4 V single cells of a structure in which positive electrodes comprising metal foils coated with an active substance and negative electrodes comprising metal foils coated with an active substance are stacked alternately by means of a separator interposed therebetween. Such square type lithium ion secondary cells have not yet been put to practical use, nor are there such cells commercially available with a large size, and high toughness, vibration resistance and impact resistance sufficient for application to electric automobiles.
For use of lithium ion secondary cells as the large-capacity batteries applicable to electric automobiles or load leveling of electric power, it is necessary first of all to enlarge their electric capacity.
The lithium ion second batteries used for such purposes are usually designed to be a square-type cell comprising an assembled cell of series-connected single cells each of which consists of several ten to about 100 electrodes associated in laminate so that the positive electrode and the negative electrode are arranged alternately by means of the separator interposed therebetween.
Especially, in application to electric automobiles, the said batteries are required to be enlarged in size and to have high toughness, vibration resistance and impact resistance. This requires the electrodes themselves to have long charge-discharge cycle life as well as high toughness, vibration resistance and impact resistance. Also, the structure of the single cells comprising a stacked assembly of such electrodes needs to be designed to have equally high toughness, vibration resistance and impact resistance.
It is demanded to enlarge the size of the lithium ion secondary cells and to enhance toughness as well as vibration resistance and impact resistance of the lithium ion secondary cells.
In case of the enlargement of a lithium ion secondary cell, such lithium ion secondary cell involves a problem that the heat generated in the inside of the cell during charge and discharge tends to accumulate in the battery, thereby causing a rise of internal temperature of the cell, even above the permissible level. So, there needs to be a release of such heat to the outside of the cell. A need for a secondary cell which can endure rapid charge and discharge is especially high in application to electric automobiles. The conventional lithium ion secondary cells have the problem that heat is accumulated in the inside of the cell as rapid cycles of charge and discharge are repeated, causing a rise of internal temperature of the cell above the allowable level.
As a result of the present inventors' earnest studies for solving the above problems, it has been found that:
(I) a lithium ion secondary cell comprising a single cell comprising positive electrodes composed of a metallic material (metal sheet) coated with a positive electrode active substance and negative electrodes composed of a metallic material (metal sheet) coated with a negative electrode active substance are stacked alternately by means of separators interposed therebetween, the lugs of the metallic materials of the respective electrodes being electrically connected to the respective conductors separately, thereby forming a collector, (i) wherein the lugs of the metallic materials of the positive and negative electrodes are respectively bunched together and clamped with the conductors, the edges of the said lugs of the electrodes and the said conductors are welded to form the collector so that electric current can be taken out through the said conductors, or (ii) wherein conductive spacers for keeping the distance between the electrodes constant are disposed between the lugs of the metallic materials of the respective electrodes in the interval of the positive or negative electrode substance and the welded portion and secured in position for electrically connecting the electrodes of each single cell separately to form the collector so that electric current can be taken out through the said spacers; or PA1 (II) a lithium ion secondary cell comprising an assembled cell composed of two or more of series-connected single cells in each of which positive electrodes composed of a metallic material (metal sheet) coated with a positive electrode active substance and negative electrodes composed of a metallic material coated with a negative electrode active substance are stacked alternatively by mean of separators interposed therebetween, in which the lugs of the metallic materials of the respective electrodes are electrically connected to the conductors separately, thereby forming a collector, and conductors electrically and thermally connected to the collector are so arranged that at least one conductor per cell for each electrode is extended, directly from each single cell, to the outside of the cell through the wall of its case so that electric current can be taken out through the said conductors while allowing release of the heat accumulated in the cell during charge and discharge to thereby prevent rise of internal temperature of the cell, PA1 the lithium ion secondary cells (I) and (II) have high toughness, vibration resistance and impact resistance, and are capable of effectively preventing rise of internal temperature of the cell. On the basis of the finding, the present invention has been attained. PA1 positive electrodes composed of a metallic material (metal sheet) coated with a positive electrode active substance; negative electrodes composed of a metallic material (metal sheet) coated with a negative electrode active substance; separators interposed between said positive and negative electrodes; lugs of said metallic materials where said active substance is not coated; conductors electrically connected to said lugs of the positive and negative electrodes separately; and conductive spacers disposed between said lugs of the positive and negative electrodes separately for maintaining constant the spacing between the positive and negative electrodes, PA1 said positive and negative electrodes being assembled in laminate alternately, and the spacers disposed between the lugs of the positive electrodes and the spacers disposed between the lugs of the negative electrodes being respectively secured in position so as to electrically connect the electrodes of the single cells so that electric current may be taken out through said spacers. PA1 positive electrodes composed of a metallic material (metal sheet) coated with a positive electrode active substance; negative electrodes composed of a metallic material (metal sheet) coated with a negative electrode active substance; separators disposed between said positive and negative electrodes; lugs of said metallic materials where said active material is not coated; and conductors connected separately to said lugs of the positive and negative electrodes, PA1 the conductors electrically and thermally connected to said collectors being so arranged that at least one conductor per cell for each electrode is extended directly from each cell to the outside of the cell container through the wall thereof so that electric current can be taken out through said conductors while allowing release therethrough of the heat accumulated in the cell during charge and discharge, thereby preventing a rise in temperature in the cell.


A method and apparatus for the forming of a solder deposit on an SMD pad on a printed circuit or hybrid board. This formed solder deposit is in a defined three-dimensional well having the proper profile and a defined solder gap. The solder before forming can be solid solder or a solder paste. By the placement of a mesh on the surface of the circuit board with the solder in place on the pads, applying a slight positive pressure on a rigid or elastic surface on the other side of the mesh, and subjecting this system to a temperature just low enough to reflow the solder by means of a heat transfer fluid, then cooling the board to solidify the solder, a product results having the above properties. The duration of the application of heat and pressure is made so brief, that the laminate structure of the board and the coating thereon remain substantially unaffected. A circuit board with the solder so formed thereon.

1. Field of the Invention
The invention relates to a method for the forming of a solder deposit on an SMD pad on a printed circuit or hybrid board. This formed solder deposit is in a defined three-dimensional well having the desirable profile and a defined solder gap. It is immaterial whether the solder before forming is solid solder or a solder paste. By the placement of a mesh on the surface of the circuit board with the solder in place on the pads, applying a slight positive pressure on a rigid or elastic surface on the other side of the mesh, and subjecting this system to a temperature just low enough to reflow the solder by means of a heat transfer fluid either liquid or gaseous, then cooling the board to solidify the solder, a product results having the above properties. The invention also relates to apparatus for forming this solder deposit as well as a circuit board with the solder so formed thereon.
2. The Prior Art
Various methods are known for applying solder selectively to printed circuit boards (PCBs) in such a way that following the assembly of the boards with Surface Mount Device (SMD) components, the boards can be electrically and mechanically connected to the components by reflow soldering methods.
In particular, the prior art uses a method in which the solder deposit is applied to the selected regions of the PCB in the form of a deposit of solder by screen printing or stencil printing with soldering pastes. While this method is in common use today, nevertheless, in many respects, this method cannot be considered optimal:
1--the investment cost of screen printing machines, screens and masks or stencils required is considerable;
2--the screens or stencils that must be used wear regularly;
3--the entire screen printing process must be monitored continuously because it cannot be precluded that the screens used may become plugged in some regions;
4--so-called thin solder deposits are often produced, which can mean low or no mechanical and thermal load capacity for the solder connections based on them;
5--thixotropic properties change while pastes are exposed to variations in temperature, humidity, evaporation of solvent and shearing conditions;
6--soldering pastes are expensive;
7--the resolution of the screen printing method is limited; and
8--the optoelectronic positional recognition of assembly systems involves great difficulties not only because of solder paste deposits that do not properly match the intended contour resulting in deviations in production, but also because of movement of the PCB itself.
9--The flexibility of interlinked production lines having screen printing is greatly impaired because these machines entail considerable set-up times and adjustments.
10--Moreover, the heating speed of the introduction of heat in reflow soldering with solder pastes has proven to be limited, because in the heating process, volatile ingredients and solvents from the paste have to evaporate which takes time.
11--Other disadvantages associated with solder paste are: a)bubble formation, b)oxidation of the soldering paste, c)fine granulation and the like.
Another previously used method in the prior art is known as immersion application of solder to PCBs. In this method, a prepared PCB is dipped into and removed from a solder bath. After being removed and following a cooling down phase, the metallized regions of the PCB provided with a solder resist means are provided with a solder deposit, which, however, has a more or less convex cross-sectional shape; this rounded surface forms because of the high surface tension of solder. The height of the solder deposit is also dependent on the dimensions in the plane of the PCB of the regions to which solder is to be applied, so that when such regions have different dimensions, variably high solder deposits necessarily result.
U.S. Pat. No. 5,051,339 issued Sep. 24, 1991 Friedrich et al., the so-called "OPTIPAD" process, is an attempt to overcome some of these disadvantages. Because this is an immersion process, there are no foreign ingredients, that is, no ingredients but solder in the solder deposits.
The process, simply stated, involves procuring a PCB having thereon a solder mask with pads exposed, laminating thereto a photoimageable layer of perhaps 5 mil in thickness, exposing and developing so that everything is masked but the pads to be soldered, immersing the thus prepared PCB into molten solder, and then contacting the board with a closure element to maintain the solder in place until it solidifies. Optionally, the limiting layer, a photoimageable solder resist mask or a regionally applied foil layer, can be left on if the component has leads which must be connected to the pads or can be removed if SMD lead-less components are used.
This patentee has pointed out that the use of hot air or hot oil leveling is not considered to be close prior art, whereas immersion solder application without ensuing air leveling is.
Some of the specifics of this invention are as follows:
solder bath temperature=250 degrees C.; PA1 optionally apply flux prior to immersion; PA1 optionally apply a primary application of solder; PA1 optionally supply turbulence in the solder bath; PA1 optionally employ closure elements with elastic surfaces; PA1 closure elements must not be wettable by solder; PA1 closure elements may have a deformably embodied closure surface, pressed into the voids located above the regions to which solder is to be applied; PA1 optionally have different temperature zones for quenching. PA1 with respect to solder paste, screen printing has already reached its limit; PA1 inability of the paste to maintain its profile after printing, therefore PA1 all the peripheral problems associated with paste and screening; PA1 buried defects in reflowed soldered joints using paste which can only be seen by X-ray examination; PA1 these defects also due to failure of some components of the paste to fully evaporate during pre-heating or reflow, with PA1 consequent solder joints with reduced peel strength; PA1 requirement for highly activated fluxes;
The coating of the PCB with the temporary soldering top mask is considered to be an indispensible part of the invention. The reason the patent application was allowed to issue was that the closest prior art did not contain the step of covering, with at least one closure element at a defined contact pressure, the voids located above the regions to which solder is to be applied when filled in the soldering bath with liquid solder.
The "OPTIPAD" process requires the use of a 5 mil temporary coating which is imaged, developed where the pads are and then immersed in molten solder. Others are attempting to modify this process by screening the molten solder into the pad wells. Stripping the temporary layer leaves behind a 5 mil high pillar of solder. Aside from the need for expensive equipment which is not commercially available, this process has two major problems:
1--When the temporary coating sees molten solder it cures extensively and is difficult to remove even when stripping with caustic soda which has the other effects of not only dulling and oxidizing the solder, but of attacking the permanent mask.
2--When the 5 mil solder mask is stripped it leaves pillars of solder which in fine pitch applications when mated with their components collapse and generate extensive shorts.
3--Any attempt to reduce the thickness of the mask in order to reduce the height of these pillars would result in a greater degree of curing and an even more difficult stripping operation.
In addition to the '339 patent mentioned above, there are two other relevant publications; a paper by W. J. Maiwald of Siemens entitled, "Reliable Reflow Soldering Techniques using Preformed Solid Solder Deposits, Part 2--The Assembly Process" and the joint paper by M. Weinhold of DuPont entitled, ". . . Part 1--The Printed Circuit Fabrication Process".
The "SIPAD" process of Siemens combines a few known technologies and produces a flat solid solder deposit on the PCB. The processing steps are applying solder pastes onto boards with permanent solder masks, melting of the solder paste and flattening of the round, humped solder deposits by a thermal/mechanical process.
The major problems which both the "OPTIPAD" and the "SIPAD" processes have attempted to address are the following:
1--opens and shorts, squeezing out of solder and resultant solder bridging; this latter occurs at assembly in the "OPTIPAD" process, and while flattening in the "SIPAD" process
2--low packing density and inability to solder with high pin counts without extensive design modifications
3--the printing of solder paste:
4--achieving the required shape of the deposit;
5--presence of a "hump", the meniscus, makes positioning of fine pitch components difficult resulting in unacceptable tolerances;
6--solder balls;
7--shelf-life of solder joint; short storage times;
8--poor solderability due to too thin deposits. Hot Air Solder Leveling is notorious for leaving thin deposits, with consequent growth of an intermetallic phase preventing wetting of the SMD solder pads during reflow or wave soldering;
9--poorly defined soldering gap;
10--inability to quantify and standardize solder deposit and solder gap;
11--yield after soldering. First-pass yields in standard applications are running at 60-70%, while for many fine pitch cases they are only 10%; rework is extensive;
12--overall cost;
13--quality of board and solder joint.
The solutions and benefits both of these approaches have attempted to achieve are as follows:
1--removal of the solder paste printing process from the assembler's operation; the PCB fabricator can supply to the assembler circuits with a solid, flat solder deposit. New processes can be used to replace solder paste printing and which obviate the need for cleaning the PCB assemblies without the risk of solder balls or other contamination;
2--guaranteed reflow solderable PCBs;
3--unlimited good solderability of the PCB;
4--small solder structures;
5--a defined solder gap; solder in a defined three-dimensional well, i.e., an excellent profile;
6--assembler would then use a 100% tested presoldered board since faults arising from solder application can be separately controlled, eliminated or reworked at the PCB fabricator without the obstruction of components;
7--the problem of solder paste deposits being deformed when the component terminals touch down is non-existent with this method. Components can be placed on a flat surface which would permit the use of fine-pitch flat packs and TAB assembly with automated equipment;
8--finer PCB structures can be implemented;
9--practically no shorts;
10--no solder balls;
11--too thin solder layers are not encountered;
12--fluxing agents can be optimized;
13--unlimited shelf-life between placement and soldering; longer guaranteed storage time; reduction in growth of the intermetallic phase resulting in higher peel strength;
14--the possibility of quantifiable and standardized solder deposits and solder joints;
15--better yield after soldering with considerable reduction of rework; higher first pass yields;
16--better overall quality of boards and solder joints; improved product consistency;
17--lower cost due to faster throughput in assembly with shorter SMD assembly lines.
Neither of these two processes, i.e., the "OPTIPAD" nor the "SIPAD", have been completely successful. The "OPTIPAD" process is run in an extremely aggressive environment, that is, molten solder at 450 degrees F. As a consequence, the so-called limiting layer or temporary film is severely cured and cannot easily be removed even with strong caustic solution. In the worst case, the permanent mask is also damaged. Attempts to resolve this by screening molten solder have had not only the same problem but in addition there is severe dulling of the solder undoubtedly due to its oxidation. As a consequence, any solder joint formed therefrom would probably have a short storage life due to intermetallic phase formation. Furthermore, this process requires the development of unique and expensive equipment for its implementation.
"SIPAD" also requires highly specialized equipment although attempts are being made to run this process in a conventional multilayer press normally used for PCBs. The problem here is that this type of press requires about 2000 psi before activation, and though the platens see the top of the solder first, they then contact the PCB itself and thermally shock the laminate, oftentimes scorching and mechanically damaging the solder mask as well. Furthermore, the solder when compressed, squeezes sideways as a very thin film or foil. While this problem can be solved by various techniques to remove the film, it results in extensive and expensive rework and fine droplets of the thus squeezed out solder end up as solder balls.
On the other hand, the "SIPAD" process uses the solder in the well to solder not the pillar of "OPTIPAD"; the process of this invention uses both.
Since solder "wicking" can be either sideways or upwards, in order for Siemens to achieve their maximum densities on fine pitch, they must change the design of their pads by elongating them. Since they are a company completely integrated vertically, this can be done by their designers, not so with the majority of OEM's. Wicking upwards is, of course, desirable; sideways is not.
In summary, both of these new processes leave much to be desired and are not practical in their present state of development. As a consequence, the study which resulted in this subject invention was undertaken.


A ferrofluid power generator with micro vortex generator is disclosed, which is capable of generating an induced current by enabling a ferrofluid having a plurality of magnetic particles to flow in a closed circuit, the device comprising a vortex generator and a induced current unit. The vortex generator further comprises a first inlet, a first outlet and a plurality of cavities, which is capable of accelerating the rotation speed of the magnetic particles by virtue of employing the plural cavities to enable the magnetic particles to rotate while the ferrofluid passing through the plural cavities. The induced current unit is substantially a tube having a second inlet and a second outlet, where the second inlet is coupled to the first outlet of the vortex generator for accepting the ferrofluid with rotating magnetic particles to flow therein and through so as to induce a change of magnetic flux to occur and generate an induced current accordingly.

There are many types of electrical generators, most of which convert thermal energy to fluid energy to mechanical energy to electrical energy. The principal sources of electrical power convert thermal energy generated by burning coal or gas or by atomic fission to superheated steam which is then converted to rotary mechanical power through a turbine which, in turn, drives an electromechanical generator.
It has also been proposed to use a closed loop ferrofluid system to drive a turbine for generation of power. In such a system, ferrofluids that undergo large changes in their magnetic properties with temperature are subjected to heating and cooling at separate points of the closed loop so that, by use of an electromagnet, a self-pumping action can be created which may be used to drive the turbine. Nevertheless, these prior art electrical generators employ a plurality of large-sized mechanically moving elements for generating electricity, that are difficult to maintain, repair, and operate quiet with little vibration. In this regard, these prior art electrical generators have limited usages especially in the apparatuses requiring high precision, which are mostly powered by battery.
In view of the above description, there are several prior-art devices dealing with the matter. Namely, a ferrofluidic electrical generator is disclosed at U.S. Pat. No. 4,064,409, titled "FERROFLUIDIC ELECTRICAL GENERATOR" by Charles M Redman, which is an electrical generator utilizing heating and cooling of separate points in a closed circuit ferrofluid system for enabling the ferrofluid therein to experience rapid change in their magnetic properties with temperature and thus generate an induced current by virtue of the change of rate of magnetic flux, so as to achieve the object of simplifying the generation of electrical power by eliminating the mechanical stages and directly from heat energy. Nevertheless, the referring ferrofluidic electrical generator posses shortcomings list as following:                (1) The flowing of the ferrofluid circulating the closed loop of the referring generator is comparatively slow since it is enabled only by the rapid magnetic properties change with respect to temperature change, and as the consequence, the electric power generated by the referring generator is not preferred since the induced current is proportional to the rate of change of the magnetic flux which is correspondence to the velocity of magnetic particles in the ferrofluid.        (2) The temperature change of the ferrofluid of the referring generator is enabled by thermal conduction, which is not efficient enough to cause rapid magnetic properties change and thus is not able to induce sufficient magnetic flux change for generating preferred induced current.
Another prior-art electrical generator as disclosed at U.S. Pat. No. 6,504,271 and U.S. Pat. No. 6,489,694, both by Jacob Chass, is a ferrofluidic electromagnetic power generator installed within a rotating object, such as the interior of a vehicular tire, capable of generating electric current in an electrical coil wound about an elongated, hermetically sealed housing made of non-magnetic material, partially filled with magnetized ferrofluid, by which rotation and horizontal velocity of the tire will agitate and propel the magnetized ferrofluid within the sealed housing enabling the magnetic particles in the ferrofluid to rotate and move and thus causing induction in the electrical coil with respect to the change of rate of magnetic flux.
Yet, another prior-art electrical generator is as disclosed by F. Gazeau in Physical Review p. 614–618 (1997). The foregoing electrical generator submits a CoFe2O4 ferrofluid in rigid rotation (and then in a Couette flow) to an alternating magnetic field, by which the magnetic particles in the ferrofluid behave as nanomotors or nanogenerators depending on the relative values of fluid vorticity and field frequency. It demonstrates the energy conversion between the magnetic and kinetic degrees of freedom of the particles. The effect of a hydrodynamic shear on the spectrum of relaxation times evidences an intimate structure of the ferrofluid consisting of small chains of dipoles. Nevertheless, the generator utilizing Couette flow effect requires to have an additional energy exerting thereon for causing a set of concentric cylinders to rotate relatively, which is not preferable.
Therefore, the present invention considers the abovementioned shortcomings and desires to come up with a ferrofluid power generator with micro vortex generator capable overcoming the same.

Device of micro vortex for ferrofluid power generator

Industrial Technology Research Institute


An analog proportional pressure control 3-way valve includes an elongate cylindrical valve housing having an axial through bore defining an interior chamber, one end of the housing comprising an end port opening, a plurality of axially spaced side port openings defining an inlet and an outlet, and an axial opposite end comprising a sleeve end receivable in a solenoid, in use. A valve member is movable in the chamber at the port end for selectively controlling fluid pressure through the chamber between the end port opening and the outlet in the neutral position or between the inlet and the outlet in a regulated position. A solenoid plunger is movable in the chamber at the sleeve end and is operatively associated with the valve member for positioning the valve member. A stop is mounted to the housing at the sleeve end for retaining the plunger in the chamber. A pressure dividing circuit divides regulated pressure between the outlet and the end port opening in the regulated position of the valve member to create an intermediate pressure to balance force from the solenoid.

In one form of a fluid pressure control valve, a flow control element, such as a spool or valve member, is movably positioned in a valve chamber between first and second valve positions for selectively fluidically coupling valve ports. The spool member may be directly actuated by a movable armature or plunger. A solenoid controllably positions the plunger, which results in movement of the spool from a neutral position to an actuated position. Typically, a coil spring is used for biasing the spool to the neutral position. Energization of the solenoid coil produces a magnetic force acting on the plunger which is related to a gap between the plunger and a stop. This relationship is represented by a curve in which force is generally inversely proportional to gap. With an on/off type valve, the magnetic force exceeds the opposing spring and flow forces to provide continuous movement of the plunger to a fully actuated position.
With a proportional type valve, it is necessary to control the plunger to stop at intermediate positions. An example of such a proportional valve is shown in Kolchinsky, U.S. Pat. No. 4,790,345. This patent shows a valve housing including a sleeve having first and second tube portions connected by a non-magnetic bridge. The mating surfaces of the bridge and tube portions are conical. This construction changes magnetic behavior as by modifying the above-described curve to provide constant force during the portion of the stroke at which the plunger is at an axial position corresponding to position of the bridge. As a result, the plunger moves until the magnetic force is balanced with the spring and flow forces so that the plunger stops at an intermediate position. As is known, the magnetic force depends on voltage applied to the coil. Thus, by varying coil voltage the stop position varies. Thus, movement of the spool can be controlled to regulate flow by varying input voltage.
In the case of a pressure control valve, a similar tube is used. However, the force of the pressure differential over the cross section of the spool cross section opposes the magnetic force. Therefore, the larger the diameter of the spool, the larger the required magnetic force.
While such typical proportional valves are satisfactory, they are also expensive to produce because of the manufacturing steps required in constructing the tube with the bridge.
Clark, U.S. Pat. No. 4,604,600, discloses an alternative construction having a one piece non-magnetic tube. This valve has a conical lip in either the plunger or stop and not the tube wall. Particularly, this design uses a conical lip on either an outer wall of the stop or the plunger or on an inner recess for a cylindrical nose of either the stop or the plunger. The nose is received in a cylindrical recess on the other of said parts. In all cases, there is a cylindrical joint between the plunger and stop. This construction is believed to provide a poor performance compared to the structures using the magnetic bridge.
It is also desirable to increase regulated pressure capacity for a given solenoid force without decreasing spool diameter. Decreasing spool diameter lowers pressure capacity.
Finally, it is desirable to decrease frictional forces relating to axial sliding movement of the plunger and valve member.
The present invention overcomes one or more of the problems discussed above.

Analog proportional pressure control three-way valve


A vehicle steering apparatus for improving steering feel when changing the angle of a steered wheel with a motor. An IFS torque compensation unit includes an oversteer IFS torque compensation gain calculation unit, which obtains a larger IFS torque compensation gain as a control target element increases during oversteer control. When an oversteer state occurs, the IFS torque compensation control unit outputs a corrected gain, which is based on the IFS torque compensation gain.

The present invention relates to a vehicle steering apparatus.
A steering control system, which controls the yaw moment of a vehicle by controlling the steering angle of steered wheels based on a vehicle model (vehicle motion model), has been proposed in recent years (refer to, for example, Japanese Laid-Open Patent Publication No. 2002-254964). The vehicle model is generated by modeling the relationship between vehicle-condition parameters, such as vehicle velocity and yaw rate, and motion states of the vehicle. An intelligent front steering (IFS) system is one example of such a steering control system.
The IFS system integrally executes electronic control associated with steered wheels, such as variable gear ratio control and power assist control, based on a plurality of vehicle-condition parameters. The variable gear ratio control changes the transmission ratio (gear ratio) of the steered wheels relative to the turning angle of the steering wheel. The power assist control applies an assist force to the steering system of the vehicle.
For example, the IFS system calculates target values (e.g., a target yaw rate) of vehicle-condition parameters based on the vehicle model. Based on the target values, the system determines the steering characteristic of the vehicle and calculates a control amount for the steered wheels. When the vehicle is in an understeer state, the system executes such control that reduces the turning angle of each steered wheel (understeer control). When the vehicle is in an oversteer state, the system executes such control that steers each steered wheel at an angle oriented in a direction opposite to the direction of the actual steering angle. That is, the system executes control for counter-steering (oversteer control). This stabilizes the behavior of the vehicle even under conditions where the behavior of the vehicle is likely to become unstable, such as on a low-friction road.
Such understeer control and oversteer control are executed by changing an ACT angle, which is a steering angle for the steered wheels produced by motor drive, by actuating a variable gear ratio actuator. Thus, the steering operation performed by the driver does not necessarily have a constant relationship with the movement of the steered wheels. The expected steering torque may differ from the actual steering torque. This may result in an uncomfortable steering feel.


Disclosed is a sorting system configured to sort a plurality of components, such as computer chips. The handler comprises a component handler configured to sort a plurality of components into groups; a plurality of receptacles on the component handler, each of the receptacles adapted to receive one of the sorted groups of components; at least one indicator associated with at least one of the receptacles, the at least one indicator being activated when the associated receptacle is filled to a selected amount with components; a plurality of bins, each of the bins being associated with one of the receptacles on the component handler; and at least one indicator on at least one of the bins, wherein the at least one indicator on the bin is activated when the receptacle associated with that bin is filled to a selected amount.

1. Field of the Invention
The invention relates to computer chips. More particularly, the invention relates to a system for efficiently testing and sorting computer chips.
2. Description of the Related Art
During production of computer chips, including memory chips, processor chips and the like, manufacturers often perform a series of tests on the chips to determine the chip quality, such as, for example, the percentage of memory cells that are functioning properly within the chip. The chips are often tested and sorted using a chip handler or handling device, which is a well-known device that performs a series of tests on the chips and then sorts the chips into groups according to the chip quality that was determined during testing.
For example, the chip handler may test the chips and determine that a certain number of the chips have memory cells with no defects. The chip handler assembles these chips together in a common group corresponding to chips of the highest quality. Other chips may be tested and found to have some memory cells that are defective. These chips are assembled together in a separate group corresponding to chips that have a lower quality. This process is repeated until all of the chips are tested and sorted into any of a wide number of groups with the chips in each group having a common level of quality.
After the chip handler tests and sorts the chips, an operator removes the chips from the chip handler and places the chips into a bin cart which has a number of separated bin spaces for storing each of the groups of chips. The operator normally maintains the chips in the bin cart in the same groups that were assembled by the chip handler so that the chips of one group are not mixed with the chips of another group. The chips are then packaged and sent to customers. Typically, the chip manufacturer sells even the lower quality chips to the customers, at a different price than the higher quality chips. The price that the manufacturer charges for a particular group of chips is largely dependent upon the quality of the chip. Generally, the manufacturer sells the lower quality chips at a lower price than that which is charged for the higher quality chips. It is therefore extremely important that the chips are sorted properly so that the manufacturer charges the customer the correct price for each of the chips.
Unfortunately, the person operating the chip handling device is often working at a very fast pace for hours at a time. Although this work is extremely important, it can also be very tedious. As a result, the operator can lose concentration and incorrectly mix the various groups of chips when removing the groups of chips from the chip handler. This results in the chips being sorted improperly so that the higher quality chips are mixed together with the lower quality chips and vice-versa. Although the operator may discover his or her mistake during the sorting process, it takes a great deal of time for the chips to be resorted and repackaged after the mistake has been discovered.
Additionally, the operator often does not realize until too late that he or she improperly mixed the chips. The improperly grouped chips are then sent to the customers, thus, a customer may pay a low price for a good quality chip that was accidentally grouped with poorer quality chips. This results in a loss of revenue for the manufacturer. Even worse, another customer may receive poor quality chips that were improperly grouped with the higher quality chips due to errors during the sorting process. This may cause problems in operation of the system into which the chip is incorporated. This results in a loss of customer good will and damage the reputation of the manufacturer.
There is, therefore, a need for a chip sorting system that avoids the aforementioned problems. The system should assist an operator in transferring computer chips from a chip sorter into a bin cart and reduce the likelihood of the chips being accidentally inserted into the wrong bin spaces in the bin cart.